Each new version, I go through what is new in the specific API area of element creation. Every CAD API has some logical divisions, from information retrieval, to element creation, to interactivity – and you can tell from how strong each area is what the factory’s focus is in the API.
Revit’s start in this area was weak – the API was more about finding elements and updating parameters than actually creating new elements and geometry. In recent releases, Revit really played catch up – I believe it now supports 101 different element creation methods.
So what’s new in 2011 in this area: in short, not much… This was not an area of focus in 2011, so there’s only a few new things in this specific area:
1. NewTruss() – now available in architecture
2. NewRebarType()
3. NewRebarHookType()
4. NewRebarCoverType()
5. FaceWall.Create()
The last one is of the greatest interest to me personally. This enables you to create a wall based on a face (typically a face that is on a mass element). This is an advanced technique used in Revit to create complex wall shapes.
Two other items deserve honorable mention here as well:
• UIDocument.PromptForFamilyInstancePlacement() – while not technically a “Element Creation” capability, it opens up some significant doors to more interactive design applications within Revit – by letting the end-user help the developer place the family instance visually.
• SolidSolidCutUtils – A new utility class to help with doing solid-to-solid cuts in the modeling environment. This is typically used either for GenericForm kind of family solids or family instances.
All in all, while this category doesn’t seem like it got much attention in 2011, the fact is that with 101 element types that can be created, it has attained a certain level of maturity. For example, if I scan the Home ribbon in 2011 – it is possible to create almost everything that is available on that toolbar (I think the exceptions are: Ceiling, Model Group (you can’t create a new one), Railing, Ramp, Stairs. That’s really not too bad – and the remaining ones are a little on the obscure/complex side.
So let me hear from you by comments? Are you really waiting for one of the missing elements that can’t be created? or are you just reluctant to do API work with geometry creation until it supports 100%? How many different kinds of elements are YOU creating in your app?
My Self . . .
- Prem...
- India
- Im Simple..I love makin frnds nd believe deeply in frndship nd love nd all the gud things...i want to make this world more b'ful..bt dnt knw how ?...
Thursday, July 14, 2011
Revit API 2011: Revit AddIn Manager – Almost Edit & Continue
If you’ve been developing for Revit for a while – you groaned significantly when, in Revit 2010, changes were made to Revit that disabled the “Edit-and-Continue” capability within a Revit add-in. That is to say – if you wanted to make a minor code change while Revit was debugging – you had to close Revit (wait for Revit to be totally closed), perform the change, then restart Revit, re-load your model, and then try to get back to the same location. Argh – seems like 2+ minutes down the drain any time this happens.
What’s Different in 2011?
I suspect due to some conversations and posts that were had on Jeremy Tammik’s blog late in the development process, the AddIn Manager has been notably improved – such that while you can’t support edit-and-continue, you can now support updating your code while Revit is running, and just re-running your command inside of Revit.
How does this work? The Addin utility is doing some lifting behind the scenes, including copying the DLL and related files to a temporary folder, and loading the .NET assembly DLL from that location.
What does this mean for us? That when we start up Revit with the debugger attached, we can run the AddInManager. From the AddInManager we can launch our command in a way that loads it into memory before starting the debug process.
While we still cannot edit and continue, we CAN open a second copy of Visual Studio, and make changes by rebuilding the project.
- it allows us to overwrite the project, because the running project was copied to somewhere else.
- we are now able to just re-start the AddIn Manager in order to start our updated version of the command.
The Features of the AddIn Manager
The behind-the-scenes mechanics are described above. It also has (obviously) been enhanced to support the new “.addin file” mechanism rather than the Revit.INI mechanism of registering addins. The command also supports some additional options which can be a little confusing at first. The list of AddIn Manager commands looks like this:
What’s the deal with all this manual, automatic and faceless?
The Manual vs. Automatic entries refer to the new TransactionMode and RegenerationMode that must be assiged to each command. Because the AddIn Manager is going to invoke your AddIn, it would be a problem if AddInManager specified Automatic mode but your code specified manual mode. So you have to pick automatic or manual based on what YOUR command is defined as. NOTE: No mix/match on transaction and regeneration mode… you have to be either Auto/Auto or Manual/Manual. The application will stop you if you pick the wrong one (although the error message leaves something to be desired).
Faceless, while the mechanism seems a little clumsy – is a nice little feature. Fundamentally – it remembers the last command that you executed, and will just execute that again (no user interface, it just does it – that way you don’t need to re-browse, re-select, and re-run the command in question).
Conclusion
If you occasionally work with API developers – get a copy of the AddIn Manager to make it easier to test and setup API AddIns! If you’re a developer, there are now many good reasons to set up the AddIn Manager. So get to it! It’s in the Revit SDK installation folder.
Enter the “Revit AddIn Manager” – part of the Software Development Kit. This tool has been around since 2009, I think – it historically provided handy mechanism for a developer to test External commands or applications – even when they forgot to add them to the REVIT.INI file. It could both update the INI file for you, or even just launch the command in session.
I suspect due to some conversations and posts that were had on Jeremy Tammik’s blog late in the development process, the AddIn Manager has been notably improved – such that while you can’t support edit-and-continue, you can now support updating your code while Revit is running, and just re-running your command inside of Revit.
How does this work? The Addin utility is doing some lifting behind the scenes, including copying the DLL and related files to a temporary folder, and loading the .NET assembly DLL from that location.
What does this mean for us? That when we start up Revit with the debugger attached, we can run the AddInManager. From the AddInManager we can launch our command in a way that loads it into memory before starting the debug process.
While we still cannot edit and continue, we CAN open a second copy of Visual Studio, and make changes by rebuilding the project.
- it allows us to overwrite the project, because the running project was copied to somewhere else.
- we are now able to just re-start the AddIn Manager in order to start our updated version of the command.
The Features of the AddIn Manager
The behind-the-scenes mechanics are described above. It also has (obviously) been enhanced to support the new “.addin file” mechanism rather than the Revit.INI mechanism of registering addins. The command also supports some additional options which can be a little confusing at first. The list of AddIn Manager commands looks like this:
What’s the deal with all this manual, automatic and faceless?
The Manual vs. Automatic entries refer to the new TransactionMode and RegenerationMode that must be assiged to each command. Because the AddIn Manager is going to invoke your AddIn, it would be a problem if AddInManager specified Automatic mode but your code specified manual mode. So you have to pick automatic or manual based on what YOUR command is defined as. NOTE: No mix/match on transaction and regeneration mode… you have to be either Auto/Auto or Manual/Manual. The application will stop you if you pick the wrong one (although the error message leaves something to be desired).
Faceless, while the mechanism seems a little clumsy – is a nice little feature. Fundamentally – it remembers the last command that you executed, and will just execute that again (no user interface, it just does it – that way you don’t need to re-browse, re-select, and re-run the command in question).
Conclusion
If you occasionally work with API developers – get a copy of the AddIn Manager to make it easier to test and setup API AddIns! If you’re a developer, there are now many good reasons to set up the AddIn Manager. So get to it! It’s in the Revit SDK installation folder.
Enter the “Revit AddIn Manager” – part of the Software Development Kit. This tool has been around since 2009, I think – it historically provided handy mechanism for a developer to test External commands or applications – even when they forgot to add them to the REVIT.INI file. It could both update the INI file for you, or even just launch the command in session.
Revit API 2011: The New Way to Find Elements
For the uninitiated, much of the core work in a Revit application involves finding elements within the Revit database. Whether it’s finding exterior walls, 3D Views, or wall types – it’s always the same concept… Doing a lookup from the Revit to get a list of elements.
This is an area that “the factory” has improved upon release-after-release… From the early days, where you always had to cycle through everything – through the newest incarnation, today. I think I’m counting right that this is the 4th generation of the element iteration API. And no more ignoring what’s new – because you’re required to use the new method in 2011!
The 2011 Approach
The factory has really created something great here – something that is mature and answers almost anything you could want in an element iteration API. And they’ve really tried to do it in a way that matched the best and most modern approaches in .NET – such as LINQ.
The fundamental concept for iteration is the FilteredElementCollector class.
Getting Started
You construct the class in one of three ways:
// get ready to filter across an entire document
FilteredElementCollector coll =
new FilteredElementCollector( myDoc );
or
// get ready to filter across just my pre-selected set of
// elements!
FilteredElementCollector coll =
new FilteredElementCollector( myDoc, myElementCollection );
This is great when you’d rather not search your entire model when you’ve already got the subset you want…
or
// get ready to filter across just the elements visible in a view
FilteredElementCollector coll =
new FilteredElementCollector( myDoc, viewId );
This is equivalent to the old mechanism of the View.Elements collection – which is now gone.
These constructors just get you started… Then it’s time to move on to the filtering.
Filtering Mechanisms with FilteredElementCollection
The factory has introduced three different categories of filtering in 2011:
• Logical (operations like AND/OR)
• Quick (operations that are FAST)
• Slow (operations that take a bit longer)
While these kinds of things have probably conceptually always existed, but they were found out by experimentation rather than Autodesk documenting and sharing them up front…
• Quick
o ElementCategoryFilter / OfCategoryId()
o ElementTypeFilter / OfType()
o ElementIsElementTypeFilter /
WhereElementIsElementType()
WhereElementIsNotElementType()
o ElementOwnerViewFilter / OwnedByView(), WhereElementIsViewIndependent()
o ElementDesignOptionFilter / ContainedInDesignOption()
o ElementIsCurveDriven / WhereElementIsCurveDriven()
o ElementStructuralTypeFilter
o BoundingBoxContainsPointFilter
o BoundingBoxIntersectsFilter
o BoundingBoxIsInsideFilter
o ExclusionFilter
o FamilySymbolFilter
• Slow
o ElementParameterFilter
o ElementLevelFilter
o FamilyInstanceFilter
o FamilyStructuralMaterialTypeFilter
o PrimaryDesignOptionMemberFilter
o StructuralInstanceUsageFilter
o StructuralMaterialTypeFilter
o StructuralWallUsageFilter
o CurveElementFilter
o RoomFilter
o SpaceFilter
o AreaFilter
o RoomTagFilter
o SpaceTagFilter
o AreaTagFilter
These are documented further in the API help file in its own introductory section called “Element Iteration API”.
I’ll give some of the typical situations here:
If you know the type:
// we want walls
coll.OfClass( typeof(Wall) );
or if you know the category:
// we want Curtain Wall Panels:
coll.OfCategoryId( BuiltInCategory.OST_CurtainWallPanels );
Now here’s where it starts to get interesting… If you want to put different filters together, it can look something like this:
// We want door instances
coll.OfCategoryId( BuiltInCategory.OST_Doors ).OfClass( typeof(FamilyInstance));
What’s going on here? each filter ADDs requirements to the collector. And to make the whole thing more friendly towards combining, the methods return a pointer to their object, so that you can “chain” them together. For example, the code above would be equivalent to:
// we want door instances
coll.OfCategoryId( BuiltInCategory.OST_Doors);
coll.OfClass( typeof(FamilyInstance) );
We are updating our collector two times with the filter requirements.
The ElementType Topic
The ElementType / NotElementType can be a little confusing at first… There are two filters, the short-hand versions are:
• WhereElementIsElementType()
• WhereElementIsNotElementType()
What is ElementType? This is the renamed Symbol class in the API (re-named to match better what interactive users call things). So an “ElementType” refers to a symbol/type/definition kind of thing (a “block definition” for you AutoCAD-types). Something which is “Not an ElementType”, on the other hand – is typically something which is physically IN the model – like a specific door, line, or wall. Technically it’s a bit more broad – because it also includes items like views, etc.
That said – these two can be key filters to use to distinguish between whether you want Doors vs. Door Types, for example.
What’s the Deal with Rooms/Areas/Spaces/Tags?
Here’s a place where Autodesk’s new strategy of matching up more closely with the internal API will cause you a little bit of hassle. With Rooms/Areas/Spaces and their tags (as well as about 9 other types – see the API Introduction for the list) – there is no internal Revit type which matches them.
For example, if you look at the Room class in the 2011 API, you’ll see that it is actually a descendant of the Enclosure Class. Enclosure covers Rooms, Spaces, and Areas… Here’s the trick – Revit’s internals are obviously modeled on the “Enclosure” class – so if you’re querying by type – you can’t query on
typeof( Room ), for example.
There are some specially designed filters to compensate for this – like RoomFilter, AreaFilter, SpaceFilter, etc… These would be called as follows:
coll.WherePasses( new RoomFilter() );
The WherePasses method is another mechanism for specifying filters – you can use any filter with it.
Final Requirements of the Filter
Ok, ok – we’re almost to the payoff… But one thing I should note before we go on… If you’re used to being able to just query the whole model (for whatever reason) – you’ll find that a little bit tricky with this mechanism… Why? Because the rule is that after you construct the collector – you MUST apply at least one filter before you attempt to retrieve from it. You can’t (easily) just retrieve everything.
The closest I’ve come to it is:
// get EVERYTHING – like in the bad-old-days…
// get all the ElementTypes + all the non-ElementTypes
coll.WhereElementIsElementType().UnionWith( new
ElementIsElementTypeFilter( false ) );
Finally – Retrieving from the Filter
Sorry to make you go through all this to get to the good part! Once you have constructed your collector and applied filter(s), then it’s time to request the contents of the collector and see what you get. Autodesk has really done a nice job of implementing some .NET 3.5 goodies here, so there are a variety of options.
coll.ToElements(); Return an IList of the contents.
coll.ToElementIds(); Return an ICollection of the contents.
coll.FirstElement() Return the first Element found that matches.
But that’s only the first part – the other thing I love is that the .NET 3.5 tricks that get around another annoyance – that these query routines return pointers to “Element” – which you immediately have to convert/cast down into, say “Room” to be able to easily access the properties and methods of that class.
// get all the wall types as wall type objects:
coll.OfClass (typeof(WallType));
IEnumerable types = coll.Cast();
foreach (WallType wt in types )
{
// do something with the wall type
}
Using with LINQ
Because the FilteredElementCollector supports the IEnumerable interface – it easily can make the jump to LINQ – being able to write full-fledged queries directly in code.
This looks something like:
FilteredElementCollector coll = new FilteredElementCollector(doc);
coll.OfClass(typeof(WallType));
var bigEnoughWallTypes =
from element in coll
where element.get_Parameter(BuiltInParameter.WALL_ATTR_WIDTH_PARAM).AsDouble() > 0.5 &&
element.get_Parameter(BuiltInParameter.FUNCTION_PARAM).AsInteger() == 1
select element;
IEnumerable types = bigEnoughWallTypes.Cast();
ok, so the thin screen doesn’t lend itself to this… In any case – it’s not magic, it’s nothing you couldn’t have done before – but it DOES make your code a bit tighter and arguably easier to maintain because it’s clear what you’re doing (as opposed to doing the same thing in a query then loops with if statements).
The Final Analysis
In the final analysis – the new FilteredElementCollector is a fantastic new way of accessing data within Revit. It does take a little bit of adjustment, but once you’re there, I’d say it’s nicer than what existed before – and it has nice room to grow.
I still need to run the new things through a performance test (my impression is that they run faster than their 2010 equivalents – but I haven’t put a stopwatch to it yet). This post is already too long – so I’ll save that for another post…
This is an area that “the factory” has improved upon release-after-release… From the early days, where you always had to cycle through everything – through the newest incarnation, today. I think I’m counting right that this is the 4th generation of the element iteration API. And no more ignoring what’s new – because you’re required to use the new method in 2011!
The 2011 Approach
The factory has really created something great here – something that is mature and answers almost anything you could want in an element iteration API. And they’ve really tried to do it in a way that matched the best and most modern approaches in .NET – such as LINQ.
The fundamental concept for iteration is the FilteredElementCollector class.
Getting Started
You construct the class in one of three ways:
// get ready to filter across an entire document
FilteredElementCollector coll =
new FilteredElementCollector( myDoc );
or
// get ready to filter across just my pre-selected set of
// elements!
FilteredElementCollector coll =
new FilteredElementCollector( myDoc, myElementCollection );
This is great when you’d rather not search your entire model when you’ve already got the subset you want…
or
// get ready to filter across just the elements visible in a view
FilteredElementCollector coll =
new FilteredElementCollector( myDoc, viewId );
This is equivalent to the old mechanism of the View.Elements collection – which is now gone.
These constructors just get you started… Then it’s time to move on to the filtering.
Filtering Mechanisms with FilteredElementCollection
The factory has introduced three different categories of filtering in 2011:
• Logical (operations like AND/OR)
• Quick (operations that are FAST)
• Slow (operations that take a bit longer)
While these kinds of things have probably conceptually always existed, but they were found out by experimentation rather than Autodesk documenting and sharing them up front…
• Quick
o ElementCategoryFilter / OfCategoryId()
o ElementTypeFilter / OfType()
o ElementIsElementTypeFilter /
WhereElementIsElementType()
WhereElementIsNotElementType()
o ElementOwnerViewFilter / OwnedByView(), WhereElementIsViewIndependent()
o ElementDesignOptionFilter / ContainedInDesignOption()
o ElementIsCurveDriven / WhereElementIsCurveDriven()
o ElementStructuralTypeFilter
o BoundingBoxContainsPointFilter
o BoundingBoxIntersectsFilter
o BoundingBoxIsInsideFilter
o ExclusionFilter
o FamilySymbolFilter
• Slow
o ElementParameterFilter
o ElementLevelFilter
o FamilyInstanceFilter
o FamilyStructuralMaterialTypeFilter
o PrimaryDesignOptionMemberFilter
o StructuralInstanceUsageFilter
o StructuralMaterialTypeFilter
o StructuralWallUsageFilter
o CurveElementFilter
o RoomFilter
o SpaceFilter
o AreaFilter
o RoomTagFilter
o SpaceTagFilter
o AreaTagFilter
These are documented further in the API help file in its own introductory section called “Element Iteration API”.
I’ll give some of the typical situations here:
If you know the type:
// we want walls
coll.OfClass( typeof(Wall) );
or if you know the category:
// we want Curtain Wall Panels:
coll.OfCategoryId( BuiltInCategory.OST_CurtainWallPanels );
Now here’s where it starts to get interesting… If you want to put different filters together, it can look something like this:
// We want door instances
coll.OfCategoryId( BuiltInCategory.OST_Doors ).OfClass( typeof(FamilyInstance));
What’s going on here? each filter ADDs requirements to the collector. And to make the whole thing more friendly towards combining, the methods return a pointer to their object, so that you can “chain” them together. For example, the code above would be equivalent to:
// we want door instances
coll.OfCategoryId( BuiltInCategory.OST_Doors);
coll.OfClass( typeof(FamilyInstance) );
We are updating our collector two times with the filter requirements.
The ElementType Topic
The ElementType / NotElementType can be a little confusing at first… There are two filters, the short-hand versions are:
• WhereElementIsElementType()
• WhereElementIsNotElementType()
What is ElementType? This is the renamed Symbol class in the API (re-named to match better what interactive users call things). So an “ElementType” refers to a symbol/type/definition kind of thing (a “block definition” for you AutoCAD-types). Something which is “Not an ElementType”, on the other hand – is typically something which is physically IN the model – like a specific door, line, or wall. Technically it’s a bit more broad – because it also includes items like views, etc.
That said – these two can be key filters to use to distinguish between whether you want Doors vs. Door Types, for example.
What’s the Deal with Rooms/Areas/Spaces/Tags?
Here’s a place where Autodesk’s new strategy of matching up more closely with the internal API will cause you a little bit of hassle. With Rooms/Areas/Spaces and their tags (as well as about 9 other types – see the API Introduction for the list) – there is no internal Revit type which matches them.
For example, if you look at the Room class in the 2011 API, you’ll see that it is actually a descendant of the Enclosure Class. Enclosure covers Rooms, Spaces, and Areas… Here’s the trick – Revit’s internals are obviously modeled on the “Enclosure” class – so if you’re querying by type – you can’t query on
typeof( Room ), for example.
There are some specially designed filters to compensate for this – like RoomFilter, AreaFilter, SpaceFilter, etc… These would be called as follows:
coll.WherePasses( new RoomFilter() );
The WherePasses method is another mechanism for specifying filters – you can use any filter with it.
Final Requirements of the Filter
Ok, ok – we’re almost to the payoff… But one thing I should note before we go on… If you’re used to being able to just query the whole model (for whatever reason) – you’ll find that a little bit tricky with this mechanism… Why? Because the rule is that after you construct the collector – you MUST apply at least one filter before you attempt to retrieve from it. You can’t (easily) just retrieve everything.
The closest I’ve come to it is:
// get EVERYTHING – like in the bad-old-days…
// get all the ElementTypes + all the non-ElementTypes
coll.WhereElementIsElementType().UnionWith( new
ElementIsElementTypeFilter( false ) );
Finally – Retrieving from the Filter
Sorry to make you go through all this to get to the good part! Once you have constructed your collector and applied filter(s), then it’s time to request the contents of the collector and see what you get. Autodesk has really done a nice job of implementing some .NET 3.5 goodies here, so there are a variety of options.
coll.ToElements(); Return an IList
coll.ToElementIds(); Return an ICollection
coll.FirstElement() Return the first Element found that matches.
But that’s only the first part – the other thing I love is that the .NET 3.5 tricks that get around another annoyance – that these query routines return pointers to “Element” – which you immediately have to convert/cast down into, say “Room” to be able to easily access the properties and methods of that class.
// get all the wall types as wall type objects:
coll.OfClass (typeof(WallType));
IEnumerable
foreach (WallType wt in types )
{
// do something with the wall type
}
Using with LINQ
Because the FilteredElementCollector supports the IEnumerable interface – it easily can make the jump to LINQ – being able to write full-fledged queries directly in code.
This looks something like:
FilteredElementCollector coll = new FilteredElementCollector(doc);
coll.OfClass(typeof(WallType));
var bigEnoughWallTypes =
from element in coll
where element.get_Parameter(BuiltInParameter.WALL_ATTR_WIDTH_PARAM).AsDouble() > 0.5 &&
element.get_Parameter(BuiltInParameter.FUNCTION_PARAM).AsInteger() == 1
select element;
IEnumerable
ok, so the thin screen doesn’t lend itself to this… In any case – it’s not magic, it’s nothing you couldn’t have done before – but it DOES make your code a bit tighter and arguably easier to maintain because it’s clear what you’re doing (as opposed to doing the same thing in a query then loops with if statements).
The Final Analysis
In the final analysis – the new FilteredElementCollector is a fantastic new way of accessing data within Revit. It does take a little bit of adjustment, but once you’re there, I’d say it’s nicer than what existed before – and it has nice room to grow.
I still need to run the new things through a performance test (my impression is that they run faster than their 2010 equivalents – but I haven’t put a stopwatch to it yet). This post is already too long – so I’ll save that for another post…
Revit 2011 API: SDK Posted (a while ago)
We’re all still waiting anxiously for the official Revit 2011 product to become available… They set the expectation for today – but it’s not there yet! and it’s 7:58 AM! What’s the deal? :)
That said – I noticed last night that the final Revit 2011 SDK is available as a standalone download on the ADN page (posted back on 4/1 – and I didn’t notice).
In other news, I hope to get back onto posting the rest of my 2011 articles – I’m just temporarily buried in project work.
[Editor: And I can see that I have to go back and add to a few previously written articles. I can see at least 15 enhancements in the new SDK that were added late enough in the process that I was unaware of them! Woo-hoo, more toys!]
That said – I noticed last night that the final Revit 2011 SDK is available as a standalone download on the ADN page (posted back on 4/1 – and I didn’t notice).
In other news, I hope to get back onto posting the rest of my 2011 articles – I’m just temporarily buried in project work.
[Editor: And I can see that I have to go back and add to a few previously written articles. I can see at least 15 enhancements in the new SDK that were added late enough in the process that I was unaware of them! Woo-hoo, more toys!]
Revit 2011 API Series: RevitLookup: The New Name for RvtMgdDbg
Since the beginning of Revit development time – in the 8.0/8.1 range, the best way to learn about what is possible with the Revit API was to use a “Snoop Tool” – something that could interrogate all of the elements in the model and all of their properties.
In the beginning, there was RevitDbg – a tool by Fenton Webb at Autodesk. It used reflection to browse through a massive tree structure of all the elements in the model. It was slow, but cool.
Later, Jim Awe of Autodesk brought his Snoop tool (called “RvtMgdDbg”) from AutoCAD to Revit – bringing not just browsing of elements but also event testing as well as some test commands. This became the tool that most Revit developers cut their teeth on. That said – I’m still amazed at the number of developers who have tried to learn the API without the benefit of RvtMgdDbg… I have to imagine it’s like developing in the dark!
For all of its importance to Revit developers, RvtMgdDbg was always somewhat of a step-child at Autodesk… No one really owned it (so it was nice that they provided the source – at least 3 times over the past few years I had to upgrade it myself to support the latest version before someone at Autodesk took care of it). It was also unclear over time how it was going to be distributed – was it only for ADN members? Did you have to attend a particular AU session? Or did you just have to know the right people? Thankfully, in the past year or so Autodesk has caught on to how important RvtMgdDbg is to getting developers up-to-speed and has made it available to anyone, usually via Jeremy Tammik’s blog.
Which brings us to 2011… While not revolutionary – it is an important evolution for RvtMgdDbg. It has been adopted by the Revit API team – which means that there are resources devoted to updating it and providing it along with the SDK – under a new, more accessible name: RevitLookup. Kevin Vandecar as well as some of the Shanghai developers have done yeoman’s work in upgrading it (it is a grueling task – I know because I had to do it myself at least twice during the 2011 alpha/beta cycle).
RevitLookup can be found in the SDK folder under RevitLookup – it appears that you’ll have to build it yourself (binaries were not shipped) – but it’s great to see that this tool getting its proper due from Autodesk.
In the beginning, there was RevitDbg – a tool by Fenton Webb at Autodesk. It used reflection to browse through a massive tree structure of all the elements in the model. It was slow, but cool.
Later, Jim Awe of Autodesk brought his Snoop tool (called “RvtMgdDbg”) from AutoCAD to Revit – bringing not just browsing of elements but also event testing as well as some test commands. This became the tool that most Revit developers cut their teeth on. That said – I’m still amazed at the number of developers who have tried to learn the API without the benefit of RvtMgdDbg… I have to imagine it’s like developing in the dark!
For all of its importance to Revit developers, RvtMgdDbg was always somewhat of a step-child at Autodesk… No one really owned it (so it was nice that they provided the source – at least 3 times over the past few years I had to upgrade it myself to support the latest version before someone at Autodesk took care of it). It was also unclear over time how it was going to be distributed – was it only for ADN members? Did you have to attend a particular AU session? Or did you just have to know the right people? Thankfully, in the past year or so Autodesk has caught on to how important RvtMgdDbg is to getting developers up-to-speed and has made it available to anyone, usually via Jeremy Tammik’s blog.
Which brings us to 2011… While not revolutionary – it is an important evolution for RvtMgdDbg. It has been adopted by the Revit API team – which means that there are resources devoted to updating it and providing it along with the SDK – under a new, more accessible name: RevitLookup. Kevin Vandecar as well as some of the Shanghai developers have done yeoman’s work in upgrading it (it is a grueling task – I know because I had to do it myself at least twice during the 2011 alpha/beta cycle).
RevitLookup can be found in the SDK folder under RevitLookup – it appears that you’ll have to build it yourself (binaries were not shipped) – but it’s great to see that this tool getting its proper due from Autodesk.
Revit 2011 API: What’s New in Element Creation
Each new version, I go through what is new in the specific API area of element creation. Every CAD API has some logical divisions, from information retrieval, to element creation, to interactivity – and you can tell from how strong each area is what the factory’s focus is in the API.
Revit’s start in this area was weak – the API was more about finding elements and updating parameters than actually creating new elements and geometry. In recent releases, Revit really played catch up – I believe it now supports 101 different element creation methods.
So what’s new in 2011 in this area: in short, not much… This was not an area of focus in 2011, so there’s only a few new things in this specific area:
1. NewTruss() – now available in architecture
2. NewRebarType()
3. NewRebarHookType()
4. NewRebarCoverType()
5. FaceWall.Create()
The last one is of the greatest interest to me personally. This enables you to create a wall based on a face (typically a face that is on a mass element). This is an advanced technique used in Revit to create complex wall shapes.
Two other items deserve honorable mention here as well:
• UIDocument.PromptForFamilyInstancePlacement() – while not technically a “Element Creation” capability, it opens up some significant doors to more interactive design applications within Revit – by letting the end-user help the developer place the family instance visually.
• SolidSolidCutUtils – A new utility class to help with doing solid-to-solid cuts in the modeling environment. This is typically used either for GenericForm kind of family solids or family instances.
All in all, while this category doesn’t seem like it got much attention in 2011, the fact is that with 101 element types that can be created, it has attained a certain level of maturity. For example, if I scan the Home ribbon in 2011 – it is possible to create almost everything that is available on that toolbar (I think the exceptions are: Ceiling, Model Group (you can’t create a new one), Railing, Ramp, Stairs. That’s really not too bad – and the remaining ones are a little on the obscure/complex side.
So let me hear from you by comments? Are you really waiting for one of the missing elements that can’t be created? or are you just reluctant to do API work with geometry creation until it supports 100%? How many different kinds of elements are YOU creating in your app?
Revit’s start in this area was weak – the API was more about finding elements and updating parameters than actually creating new elements and geometry. In recent releases, Revit really played catch up – I believe it now supports 101 different element creation methods.
So what’s new in 2011 in this area: in short, not much… This was not an area of focus in 2011, so there’s only a few new things in this specific area:
1. NewTruss() – now available in architecture
2. NewRebarType()
3. NewRebarHookType()
4. NewRebarCoverType()
5. FaceWall.Create()
The last one is of the greatest interest to me personally. This enables you to create a wall based on a face (typically a face that is on a mass element). This is an advanced technique used in Revit to create complex wall shapes.
Two other items deserve honorable mention here as well:
• UIDocument.PromptForFamilyInstancePlacement() – while not technically a “Element Creation” capability, it opens up some significant doors to more interactive design applications within Revit – by letting the end-user help the developer place the family instance visually.
• SolidSolidCutUtils – A new utility class to help with doing solid-to-solid cuts in the modeling environment. This is typically used either for GenericForm kind of family solids or family instances.
All in all, while this category doesn’t seem like it got much attention in 2011, the fact is that with 101 element types that can be created, it has attained a certain level of maturity. For example, if I scan the Home ribbon in 2011 – it is possible to create almost everything that is available on that toolbar (I think the exceptions are: Ceiling, Model Group (you can’t create a new one), Railing, Ramp, Stairs. That’s really not too bad – and the remaining ones are a little on the obscure/complex side.
So let me hear from you by comments? Are you really waiting for one of the missing elements that can’t be created? or are you just reluctant to do API work with geometry creation until it supports 100%? How many different kinds of elements are YOU creating in your app?
Revit API 2011: Revit AddIn Manager – Almost Edit & Continue
If you’ve been developing for Revit for a while – you groaned significantly when, in Revit 2010, changes were made to Revit that disabled the “Edit-and-Continue” capability within a Revit add-in. That is to say – if you wanted to make a minor code change while Revit was debugging – you had to close Revit (wait for Revit to be totally closed), perform the change, then restart Revit, re-load your model, and then try to get back to the same location. Argh – seems like 2+ minutes down the drain any time this happens.
Enter the “Revit AddIn Manager” – part of the Software Development Kit. This tool has been around since 2009, I think – it historically provided handy mechanism for a developer to test External commands or applications – even when they forgot to add them to the REVIT.INI file. It could both update the INI file for you, or even just launch the command in session.
What’s Different in 2011?
I suspect due to some conversations and posts that were had on Jeremy Tammik’s blog late in the development process, the AddIn Manager has been notably improved – such that while you can’t support edit-and-continue, you can now support updating your code while Revit is running, and just re-running your command inside of Revit.
How does this work? The Addin utility is doing some lifting behind the scenes, including copying the DLL and related files to a temporary folder, and loading the .NET assembly DLL from that location.
What does this mean for us? That when we start up Revit with the debugger attached, we can run the AddInManager. From the AddInManager we can launch our command in a way that loads it into memory before starting the debug process.
While we still cannot edit and continue, we CAN open a second copy of Visual Studio, and make changes by rebuilding the project.
- it allows us to overwrite the project, because the running project was copied to somewhere else.
- we are now able to just re-start the AddIn Manager in order to start our updated version of the command.
The Features of the AddIn Manager
The behind-the-scenes mechanics are described above. It also has (obviously) been enhanced to support the new “.addin file” mechanism rather than the Revit.INI mechanism of registering addins. The command also supports some additional options which can be a little confusing at first. The list of AddIn Manager commands looks like this:
What’s the deal with all this manual, automatic and faceless?
The Manual vs. Automatic entries refer to the new TransactionMode and RegenerationMode that must be assiged to each command. Because the AddIn Manager is going to invoke your AddIn, it would be a problem if AddInManager specified Automatic mode but your code specified manual mode. So you have to pick automatic or manual based on what YOUR command is defined as. NOTE: No mix/match on transaction and regeneration mode… you have to be either Auto/Auto or Manual/Manual. The application will stop you if you pick the wrong one (although the error message leaves something to be desired).
Faceless, while the mechanism seems a little clumsy – is a nice little feature. Fundamentally – it remembers the last command that you executed, and will just execute that again (no user interface, it just does it – that way you don’t need to re-browse, re-select, and re-run the command in question).
Conclusion
If you occasionally work with API developers – get a copy of the AddIn Manager to make it easier to test and setup API AddIns! If you’re a developer, there are now many good reasons to set up the AddIn Manager. So get to it! It’s in the Revit SDK installation folder.
Enter the “Revit AddIn Manager” – part of the Software Development Kit. This tool has been around since 2009, I think – it historically provided handy mechanism for a developer to test External commands or applications – even when they forgot to add them to the REVIT.INI file. It could both update the INI file for you, or even just launch the command in session.
What’s Different in 2011?
I suspect due to some conversations and posts that were had on Jeremy Tammik’s blog late in the development process, the AddIn Manager has been notably improved – such that while you can’t support edit-and-continue, you can now support updating your code while Revit is running, and just re-running your command inside of Revit.
How does this work? The Addin utility is doing some lifting behind the scenes, including copying the DLL and related files to a temporary folder, and loading the .NET assembly DLL from that location.
What does this mean for us? That when we start up Revit with the debugger attached, we can run the AddInManager. From the AddInManager we can launch our command in a way that loads it into memory before starting the debug process.
While we still cannot edit and continue, we CAN open a second copy of Visual Studio, and make changes by rebuilding the project.
- it allows us to overwrite the project, because the running project was copied to somewhere else.
- we are now able to just re-start the AddIn Manager in order to start our updated version of the command.
The Features of the AddIn Manager
The behind-the-scenes mechanics are described above. It also has (obviously) been enhanced to support the new “.addin file” mechanism rather than the Revit.INI mechanism of registering addins. The command also supports some additional options which can be a little confusing at first. The list of AddIn Manager commands looks like this:
What’s the deal with all this manual, automatic and faceless?
The Manual vs. Automatic entries refer to the new TransactionMode and RegenerationMode that must be assiged to each command. Because the AddIn Manager is going to invoke your AddIn, it would be a problem if AddInManager specified Automatic mode but your code specified manual mode. So you have to pick automatic or manual based on what YOUR command is defined as. NOTE: No mix/match on transaction and regeneration mode… you have to be either Auto/Auto or Manual/Manual. The application will stop you if you pick the wrong one (although the error message leaves something to be desired).
Faceless, while the mechanism seems a little clumsy – is a nice little feature. Fundamentally – it remembers the last command that you executed, and will just execute that again (no user interface, it just does it – that way you don’t need to re-browse, re-select, and re-run the command in question).
Conclusion
If you occasionally work with API developers – get a copy of the AddIn Manager to make it easier to test and setup API AddIns! If you’re a developer, there are now many good reasons to set up the AddIn Manager. So get to it! It’s in the Revit SDK installation folder.
DWFplus for Revit 2012
Well, it has been forever since I've last posted... I missed the release of the 2012 API and a variety of other announcements. But I'm trying to get back on the horse.
To that end - a quick video to show what I think is a cool new feature of our Utilities for Revit 2012 product - a new utility called "DWFplus".
If you've ever looked at distributing a DWF file, and figuring that Revit ought to be making it chock-full of all my BIM data... you may have been slightly disappointed. The rules for when Revit published a parameter or didn't were arcane - and I'm still not sure if we've accurately reverse engineered them. And certain features like hyperlinks... how is it that AutoCAD can have hyperlinks but not Revit!
So DWFplus is an attempt to change that. It starts with a regular DWF export, but adds in a variety of neat stuff:
• All parameters (or selected parameters) that you want to publish
• Parameters are attached to Tags - not just the elements
• Includes 2D Hyperlinks for any URL parameters (even multiples)
• Parameters are published in 3D as well as 2D.
• Includes some neat 3d viewpoints for 3D DWF views.
Here's a little video to demonstrate:
Note: IMAGINiT Utilities for Revit is available here, and is free for clients that keep their Revit subscription with IMAGINiT.
To that end - a quick video to show what I think is a cool new feature of our Utilities for Revit 2012 product - a new utility called "DWFplus".
If you've ever looked at distributing a DWF file, and figuring that Revit ought to be making it chock-full of all my BIM data... you may have been slightly disappointed. The rules for when Revit published a parameter or didn't were arcane - and I'm still not sure if we've accurately reverse engineered them. And certain features like hyperlinks... how is it that AutoCAD can have hyperlinks but not Revit!
So DWFplus is an attempt to change that. It starts with a regular DWF export, but adds in a variety of neat stuff:
• All parameters (or selected parameters) that you want to publish
• Parameters are attached to Tags - not just the elements
• Includes 2D Hyperlinks for any URL parameters (even multiples)
• Parameters are published in 3D as well as 2D.
• Includes some neat 3d viewpoints for 3D DWF views.
Here's a little video to demonstrate:
Note: IMAGINiT Utilities for Revit is available here, and is free for clients that keep their Revit subscription with IMAGINiT.
An oddity with Drafting View mirroring
So I was asked if it was possible to mirror a drafting view using the API (apparently the built-in project mirroring doesn't cover drafting views).
It seemed straightforward enough... so I wrote a quick test... and it didn't work...
- it worked fine in a floor plan view
- it didn't work in a drafting view
- the code completed just fine - it just didn't really seem to show any difference.
My initial code is below...
- Get all the elements in the current view
- Use the new ElementTransformUtil class to figure out which could be mirrored, and mirror them.
FilteredElementCollector coll =
new FilteredElementCollector(uiDoc.Document, uiDoc.ActiveView.Id);
IList elems = coll.ToElements();
// make sure that stuff can be mirrored
List toMirror = new List();
foreach (Element elem in elems)
{
if (ElementTransformUtils.CanMirrorElement(uiDoc.Document, elem.Id) == false) continue;
toMirror.Add(elem.Id);
}
So why did this complete successfully, but not show any difference?
The answer is one of those great undocumented elements in the wilds of the Revit database. When I looked in the debugger at what I was actually attempting to mirror, I saw this:
What I see here is a mystery element called "ExtentElem" which is being copied. I have a sneaking suspicion that it might be telling the view the actual extent of what is in it... So how can we exclude it? well - it has no actual category (which is probably a sign that in general we don't want to mirror an element like that!).
So - we add a line like:
if (elem.Category == null) continue;
and voila! we have our drafting view being mirrored.
I wish that I could say that all Revit database mysteries are "easily" solvable like this - there's plenty of times where you just run into a wall, and can't get to what you want... but today's story has a happy ending!
It seemed straightforward enough... so I wrote a quick test... and it didn't work...
- it worked fine in a floor plan view
- it didn't work in a drafting view
- the code completed just fine - it just didn't really seem to show any difference.
My initial code is below...
- Get all the elements in the current view
- Use the new ElementTransformUtil class to figure out which could be mirrored, and mirror them.
FilteredElementCollector coll =
new FilteredElementCollector(uiDoc.Document, uiDoc.ActiveView.Id);
IList elems = coll.ToElements();
// make sure that stuff can be mirrored
List toMirror = new List();
foreach (Element elem in elems)
{
if (ElementTransformUtils.CanMirrorElement(uiDoc.Document, elem.Id) == false) continue;
toMirror.Add(elem.Id);
}
So why did this complete successfully, but not show any difference?
The answer is one of those great undocumented elements in the wilds of the Revit database. When I looked in the debugger at what I was actually attempting to mirror, I saw this:
What I see here is a mystery element called "ExtentElem" which is being copied. I have a sneaking suspicion that it might be telling the view the actual extent of what is in it... So how can we exclude it? well - it has no actual category (which is probably a sign that in general we don't want to mirror an element like that!).
So - we add a line like:
if (elem.Category == null) continue;
and voila! we have our drafting view being mirrored.
I wish that I could say that all Revit database mysteries are "easily" solvable like this - there's plenty of times where you just run into a wall, and can't get to what you want... but today's story has a happy ending!
Saturday, July 09, 2011
Draganflyer X6
Draganflyer X6 is an advanced helicopter that can be operated remotely without any pilot. It is designed mainly to carry wireless video cameras and still cameras. The Draganflyer X6 helicopter can be operated very easily with its hand held controller.
The Draganflyer X6 helicopter is based on a unique 6-rotor design that has been under development since early 2006. It uses 11 sensors and thousands of lines of code to self-stabilize during flight which makes it easier to fly than any other helicopter in its class. The on-board software of Draganflyer X6 is developed after extensive testing and development. Draganflyer X6 helicopter is a revolution in the field of Unmanned Aerial Vehicle (UAV).
It can be used very efficiently for various applications and it is ideal for spying on the enemy in a safe and reliable manner.
MAJOR FIELDS OF APPLICATIONS
The new Draganflyer X6 can be used in various field such as Industrial Constructions, Government Applications and Educational needs.
1)Industrial Use:
Draganflyer X6 can be used very efficiently in Bridge Constructions, Building Construction, Pipeline / Hydro-Transmission Line Inspection, Road Construction. With the help of this aircraft you can get videos and images of any site from various angels.
Equipped with a high resolution still camera (with remote zoom, shutter control and tilt) it can capture great images. And its high definition video recorder can record videos very efficiently. It has a range of 500 meters and have a flight time of 20 to 30 minutes.
It is designed specifically with easy controlling system for ease of use it. So, it is easy to fly, needs very minimal training, and provides an extremely stable aerial platform from where you can get photographs and video. It's small size and portability makes it suitable to carry it to any construction site and have it ready to fly in minutes.
2)Government Applications:
Draganflyer X6 can be used in many government applications such as Law Enforcement, Fire, Emergency Measures, Wildlife Management, Environment and Transportation. You can use this advanced machine for Disaster Response, Conservation Enforcement, Crime Scene Investigation, Crowd Control, Explosive Disposal Unit, Search and Rescue Missions, Traffic Congestion Control, Criminal Intelligence Applications, Fire Damage Assessment, Fire Scene Management any many more.
3)Educational Applications:
Draganflyer X6 is very useful in educational applications such as Advanced RC Flight Research, Aerial Archeology, Environmental Assessment, and Geological Exploration.
FEATURES AT A GLANCE:
Draganflyer X6 is unique in many terms. It has some very advanced features that make it different and more efficient then other remote controlled helicopters. Some of these features are:
1)Six Rotor Co-Axial Configuration
2)GPS Facility
3)Carbon Fiber Folding Frame
4)Handheld Flight Controller
5)Advanced Power System
6)High Damage Tolerance
7)Specially manufactured Cases
8)Engineered for Safety
9)Electronic Flight Stability
10)Telemetry Software
11)Wireless Video System
12)Anti-Vibration Camera Mount
13)HD Digital Video Camera
14)Low Light Camera
15)Thermal Infrared Camera
These various features of Draganflyer X6 makes it very useful and efficient in its work.
The Draganflyer X6 helicopter is based on a unique 6-rotor design that has been under development since early 2006. It uses 11 sensors and thousands of lines of code to self-stabilize during flight which makes it easier to fly than any other helicopter in its class. The on-board software of Draganflyer X6 is developed after extensive testing and development. Draganflyer X6 helicopter is a revolution in the field of Unmanned Aerial Vehicle (UAV).
It can be used very efficiently for various applications and it is ideal for spying on the enemy in a safe and reliable manner.
MAJOR FIELDS OF APPLICATIONS
The new Draganflyer X6 can be used in various field such as Industrial Constructions, Government Applications and Educational needs.
1)Industrial Use:
Draganflyer X6 can be used very efficiently in Bridge Constructions, Building Construction, Pipeline / Hydro-Transmission Line Inspection, Road Construction. With the help of this aircraft you can get videos and images of any site from various angels.
Equipped with a high resolution still camera (with remote zoom, shutter control and tilt) it can capture great images. And its high definition video recorder can record videos very efficiently. It has a range of 500 meters and have a flight time of 20 to 30 minutes.
It is designed specifically with easy controlling system for ease of use it. So, it is easy to fly, needs very minimal training, and provides an extremely stable aerial platform from where you can get photographs and video. It's small size and portability makes it suitable to carry it to any construction site and have it ready to fly in minutes.
2)Government Applications:
Draganflyer X6 can be used in many government applications such as Law Enforcement, Fire, Emergency Measures, Wildlife Management, Environment and Transportation. You can use this advanced machine for Disaster Response, Conservation Enforcement, Crime Scene Investigation, Crowd Control, Explosive Disposal Unit, Search and Rescue Missions, Traffic Congestion Control, Criminal Intelligence Applications, Fire Damage Assessment, Fire Scene Management any many more.
3)Educational Applications:
Draganflyer X6 is very useful in educational applications such as Advanced RC Flight Research, Aerial Archeology, Environmental Assessment, and Geological Exploration.
FEATURES AT A GLANCE:
Draganflyer X6 is unique in many terms. It has some very advanced features that make it different and more efficient then other remote controlled helicopters. Some of these features are:
1)Six Rotor Co-Axial Configuration
2)GPS Facility
3)Carbon Fiber Folding Frame
4)Handheld Flight Controller
5)Advanced Power System
6)High Damage Tolerance
7)Specially manufactured Cases
8)Engineered for Safety
9)Electronic Flight Stability
10)Telemetry Software
11)Wireless Video System
12)Anti-Vibration Camera Mount
13)HD Digital Video Camera
14)Low Light Camera
15)Thermal Infrared Camera
These various features of Draganflyer X6 makes it very useful and efficient in its work.
Most Advanced Microscope of World
Canadian center for Electron Microscopy has developed a new powerful microscope that is world's most powerful microscope till date. According to Gianluigi Botton, Director of Canadian center for Electron Microscopy, says that the power of this microscope can be thought as equivalent to "taking Hubble Telescope and aiming it at atomic level"
Titan 80-300 Cubed
This powerful microscope named Titan 80-300 Cubed was installed at the University early in the summer, and since then it has been put through its paces to achieve unprecedented resolution.
This microscope is so powerful that it can easily identify atoms, measure their chemical state and even probe the electrons that bind them together.
According to vice-president of Mc Master, Mr. Elbestawi this microscope will make McMaster a hub for a fast growing field.
Really Impressive Microscope
A group of international scientists who visited McMaster were really impressed by the amazing capabilities of this microscope. This microscope can help scientist to discover new things in biological and physical sciencesDean of Engineering David Wilkinson sees the microscope through another lens.
Titan
Titan's ability can probe structure of solid materials to the atomic level and this will have an amazing impact on development and commercialization of new technologies from biomedical devices to water quality monitoring and improved energy storage systems.
Titan
Cost of Microscope
This microscope has been build in Netherlands by FEI Company with a cost of about $15 million. This microscope can help to examine everyday products with its Nano details that can improve the efficiency of these products.
What This Microscope Can Do?
This microscope can be used to produce more efficient lighting and better solar cells, to study proteins and drug-delivery materials to target cancers. It will assess atmospheric particulates, and help create lighter and stronger automotive materials, more effective cosmetics, and higher density memory storage for faster electronic and telecommunication devices.
Funding
Funding for the microscope instrumentation was provided by the Canada Foundation for Innovation, the Ontario Innovation Trust, the Ministry of Research and Innovation of Ontario and the Ontario Ministry of Economic Development and Trade, through a partnership with FEI and McMaster University.
Titan 80-300 Cubed
This powerful microscope named Titan 80-300 Cubed was installed at the University early in the summer, and since then it has been put through its paces to achieve unprecedented resolution.
This microscope is so powerful that it can easily identify atoms, measure their chemical state and even probe the electrons that bind them together.
According to vice-president of Mc Master, Mr. Elbestawi this microscope will make McMaster a hub for a fast growing field.
Really Impressive Microscope
A group of international scientists who visited McMaster were really impressed by the amazing capabilities of this microscope. This microscope can help scientist to discover new things in biological and physical sciencesDean of Engineering David Wilkinson sees the microscope through another lens.
Titan
Titan's ability can probe structure of solid materials to the atomic level and this will have an amazing impact on development and commercialization of new technologies from biomedical devices to water quality monitoring and improved energy storage systems.
Titan
Cost of Microscope
This microscope has been build in Netherlands by FEI Company with a cost of about $15 million. This microscope can help to examine everyday products with its Nano details that can improve the efficiency of these products.
What This Microscope Can Do?
This microscope can be used to produce more efficient lighting and better solar cells, to study proteins and drug-delivery materials to target cancers. It will assess atmospheric particulates, and help create lighter and stronger automotive materials, more effective cosmetics, and higher density memory storage for faster electronic and telecommunication devices.
Funding
Funding for the microscope instrumentation was provided by the Canada Foundation for Innovation, the Ontario Innovation Trust, the Ministry of Research and Innovation of Ontario and the Ontario Ministry of Economic Development and Trade, through a partnership with FEI and McMaster University.
Chandrayaan - I: Proud for India
India's first mission to the Moon: Chandrayaan-1 , was successfully launched the morning of October 22 from the Satish Dhawan Space Centre (SHAR) in Sriharikota, India.
The spacecraft was launched into the orbit of earth by PSLV-C11 which is an upgraded version of the Indian Space Research Organization's (ISRO's) Polar Satellite Launch Vehicle. The launch took place at 02:52 Central European Summer Time.
With this launch Chandrayaan-1 started its journey to the Moon, which will culminate with a major manoeuvre - the lunar orbit insertion - in about two weeks. Once the spacecraft is orbiting the Moon, further manoeuvres will progressively lower its altitude to the final 100 km-high circular orbit.
Mission of Chandrayaan-1
This spacecraft will eject the 'Moon Impact Probe' to provide information about the lunar surface. After that mission will be continued from orbit. The spacecraft is equipped with 11 scientific instruments for lunar surface study. Three of these 11 instruments were provided by Europe (UK, Germany, Sweden) through ESA.
The European instruments are:
The Chandrayaan-1 Imaging X-Ray Spectrometer (C1XS) for measuring abundance of magnesium, aluminium, silicon, iron and titanium over the surface of the Moon.
The Smart Near-Infrared Spectrometer (SIR-2) to explore the mineral resources of the Moon, the formation of its surface features and the different layers of the Moon's crust.
The Sub-kiloelectronvolt Atom Reflecting Analyser (SARA) to study the way the Moon's surface interacts with the solar wind, and the surface's magnetic anomalies.
Chandrayaan
Collaboration of India and Europe
Indo-European collaboration on space ventures is 30 years old when ESA and ISRO signed a cooperation agreement in 1978. In 1981, an Ariane 1 launcher carried India's first geostationary satellite, Apple. So far, 13 of India's INSAT satellites have flown on Europe's Arianes.
Now with Chandrayaan-1 which is ISRO's first mission beyond Earth orbit, marks the beginning of a new era of collaboration between ESA and ISRO in space science.
According to Prof. David Southwood, ESA Director of Science and Robotic Exploration: "In an era of renewed interest for the Moon on a world-wide scale, the ESA-ISRO collaboration on Chandrayaan-1 is a new opportunity for Europe to expand its competence in lunar science while tightening the long-standing relationship with India - an ever stronger space power".
This mission is a big success not only for ISRO but for whole India. This mission is a milestone in India's space missions and now India is among those very few countries that have launched lunar missions in past.
The spacecraft was launched into the orbit of earth by PSLV-C11 which is an upgraded version of the Indian Space Research Organization's (ISRO's) Polar Satellite Launch Vehicle. The launch took place at 02:52 Central European Summer Time.
With this launch Chandrayaan-1 started its journey to the Moon, which will culminate with a major manoeuvre - the lunar orbit insertion - in about two weeks. Once the spacecraft is orbiting the Moon, further manoeuvres will progressively lower its altitude to the final 100 km-high circular orbit.
Mission of Chandrayaan-1
This spacecraft will eject the 'Moon Impact Probe' to provide information about the lunar surface. After that mission will be continued from orbit. The spacecraft is equipped with 11 scientific instruments for lunar surface study. Three of these 11 instruments were provided by Europe (UK, Germany, Sweden) through ESA.
The European instruments are:
The Chandrayaan-1 Imaging X-Ray Spectrometer (C1XS) for measuring abundance of magnesium, aluminium, silicon, iron and titanium over the surface of the Moon.
The Smart Near-Infrared Spectrometer (SIR-2) to explore the mineral resources of the Moon, the formation of its surface features and the different layers of the Moon's crust.
The Sub-kiloelectronvolt Atom Reflecting Analyser (SARA) to study the way the Moon's surface interacts with the solar wind, and the surface's magnetic anomalies.
Chandrayaan
Collaboration of India and Europe
Indo-European collaboration on space ventures is 30 years old when ESA and ISRO signed a cooperation agreement in 1978. In 1981, an Ariane 1 launcher carried India's first geostationary satellite, Apple. So far, 13 of India's INSAT satellites have flown on Europe's Arianes.
Now with Chandrayaan-1 which is ISRO's first mission beyond Earth orbit, marks the beginning of a new era of collaboration between ESA and ISRO in space science.
According to Prof. David Southwood, ESA Director of Science and Robotic Exploration: "In an era of renewed interest for the Moon on a world-wide scale, the ESA-ISRO collaboration on Chandrayaan-1 is a new opportunity for Europe to expand its competence in lunar science while tightening the long-standing relationship with India - an ever stronger space power".
This mission is a big success not only for ISRO but for whole India. This mission is a milestone in India's space missions and now India is among those very few countries that have launched lunar missions in past.
Lunar Lenders becomes more Intelligent
Advanced Lunar Lenders now will be able to automatically identify and navigate to a safe landing location, while detecting hazards in landing during final descent to surface. NASA is developing an advanced technology for lunar lenders that made them capable to land safely near resources located in potentially hazardous area.
Critical Sensor Technology
NASA's Langely Research Center has developed two critical sensor technologies. One is a three-dimensional active imaging device that measures topography of a landing area. The second device measures speed to help land precisely at the chosen site.
Langely Research Center has designed two special purpose light detection and ranging sensors to make these two devices. In addition to this Jet Propulsion Laboratory of NASA is developing certain algorithms to analyze the terrain based upon these lidar measurements.
These technologies have been integrated as part of Autonomous Landing and Hazard Avoidance Technology (ALHAT) project of NASA. These technologies are in the phase of demonstration and testing in a series of flight tests.
Bob Reisse
Bob Reisse is leading the team at Langley Research Center which is designing the lidar sensors and supporting the demonstration flight tests.
They have conducted two demonstration flights and Reisse says, "We were pleased that the two flight tests we've conducted so far have resulted in better than expected performance of these sensors."
Two Phases Of Demonstration Flights
First test that was carried out in May, was to The main objective of the first test, carried out in May, was to demonstrate the application of 3-D imaging technology or 'flash' lidar, for topography mapping and precision navigation.
Second demonstration in August was to of flight tests, completed in August, was to evaluate the capabilities of an emerging lidar technology developed at Langley. This lidar provides vehicle velocity vector, altitude and attitude with a very high degree of precision.
Lunar Lenders
Demonstration Test Procedures
In the recent demonstration test the velocimeter was carried aloft at Dryden Flight Research Center of NASA via helicopter which flew a total of six flights at various altitudes between targeted reference points.
During the demonstration tests, the helicopter flew over two target areas three miles (5 km) apart on the surface of Rogers Dry Lake. Repeated back-and-forth tracks were flown at altitudes incrementally increasing from about 300 feet to 6,200 feet (91m to 1,890m) above the lake bed while the lidar measured the relative speed, altitude, and attitude of the helicopter. Plywood circles placed on the lakebed served as reference targets for determining the ground "truth" measurements. The data was recorded on board and tagged with time and altitude information to allow post-flight processing.
Lidar Technology
Lidar Technology is much more advanced than today's systems for planetary navigating tasks. Preliminary tests shows that this technology is about 10 times more powerful than conventional radar-based sensors that were used in Phoenix Mars Lenders, in accuracy of velocity readings and rate of updates.
This precision range and directional velocity data are critical in navigating lunar landing vehicles to the pre-selected site and achieving autonomous, safe soft-landing.
Future of Lunar Lenders
This new technology has a potential for or aiding crew exploration vehicle rendezvous and docking, and Earth reentry landing systems. This can highly impact the design of future lunar and other planetary landing missions.
Critical Sensor Technology
NASA's Langely Research Center has developed two critical sensor technologies. One is a three-dimensional active imaging device that measures topography of a landing area. The second device measures speed to help land precisely at the chosen site.
Langely Research Center has designed two special purpose light detection and ranging sensors to make these two devices. In addition to this Jet Propulsion Laboratory of NASA is developing certain algorithms to analyze the terrain based upon these lidar measurements.
These technologies have been integrated as part of Autonomous Landing and Hazard Avoidance Technology (ALHAT) project of NASA. These technologies are in the phase of demonstration and testing in a series of flight tests.
Bob Reisse
Bob Reisse is leading the team at Langley Research Center which is designing the lidar sensors and supporting the demonstration flight tests.
They have conducted two demonstration flights and Reisse says, "We were pleased that the two flight tests we've conducted so far have resulted in better than expected performance of these sensors."
Two Phases Of Demonstration Flights
First test that was carried out in May, was to The main objective of the first test, carried out in May, was to demonstrate the application of 3-D imaging technology or 'flash' lidar, for topography mapping and precision navigation.
Second demonstration in August was to of flight tests, completed in August, was to evaluate the capabilities of an emerging lidar technology developed at Langley. This lidar provides vehicle velocity vector, altitude and attitude with a very high degree of precision.
Lunar Lenders
Demonstration Test Procedures
In the recent demonstration test the velocimeter was carried aloft at Dryden Flight Research Center of NASA via helicopter which flew a total of six flights at various altitudes between targeted reference points.
During the demonstration tests, the helicopter flew over two target areas three miles (5 km) apart on the surface of Rogers Dry Lake. Repeated back-and-forth tracks were flown at altitudes incrementally increasing from about 300 feet to 6,200 feet (91m to 1,890m) above the lake bed while the lidar measured the relative speed, altitude, and attitude of the helicopter. Plywood circles placed on the lakebed served as reference targets for determining the ground "truth" measurements. The data was recorded on board and tagged with time and altitude information to allow post-flight processing.
Lidar Technology
Lidar Technology is much more advanced than today's systems for planetary navigating tasks. Preliminary tests shows that this technology is about 10 times more powerful than conventional radar-based sensors that were used in Phoenix Mars Lenders, in accuracy of velocity readings and rate of updates.
This precision range and directional velocity data are critical in navigating lunar landing vehicles to the pre-selected site and achieving autonomous, safe soft-landing.
Future of Lunar Lenders
This new technology has a potential for or aiding crew exploration vehicle rendezvous and docking, and Earth reentry landing systems. This can highly impact the design of future lunar and other planetary landing missions.
Magnetic Field in a Distant Galaxy
A team of astronomers in California have detected magnetic field of a galaxy in far universe. These astronomers are studying the early universe by a powerful radio telescope. This measurement of magnetic field is as it was 6.5 billion years ago.
Prior Believes
Astronomers believe that magnetic fields within our own Milky Way and other galaxies near milky way, control the rate of star formation and the dynamics of interstellar gas. This magnetic field arose from a slow Dynamo Effect. This magnetic field in these galaxies grew very gradually as they evolved over 5 billion to 10 billion years to their current levels.
But now astronomers have reported that the magnetic field that they have measured in a distant Protogalaxy is at least 10 times greater than average value of Milky Way. This report has been published in October issue of Nature.
According to Arthur Wolfe (Professor of Physics at UC San Diego's Center for Astrophysics and Space Sciences and head of the team), this research is a Complete Surprise. The magnetic field measured is at least an order of magnitude larger than the average value of the magnetic field detected in our own galaxy.
Powerful Radio Telescope and Useful Results
Astronomers used world's largest fully steerable radio telescope for their study known as Robert C. Byrd Green Bank Telescope located in Green Bank, West Virginia. This grand telescope is operated by National Radio Astronomy Observatory of National Science Foundation.
They studied DLA-3C286 protogalaxy located in a region of northern sky.
Magnetic Field outside our galaxy is very less know formerly. Prior to this study astronomers have measured magnetic field of only one nearby galaxy but that field was very weak.
A team of Swiss and American astronomers in July 17 issue of Nature magazine reported that they have found that magnetic field of about 20 distant galaxies were as when the universe was only a third of its current age as they are in the mature galaxies today. This study was done by using bright light from quasars.
Wolfe said those indirect measurements and his team's latest direct measurement of a distant galaxy's magnetic field "do not necessarily cast doubt on the leading theory of magnetic field generation, the mean-field-dynamo model, which predicts that the magnetic field strengths should be much weaker in galaxies in the cosmological past."
Challenge to Dynamo Model
These results have put a challenge before Dynamo Model.
According to Arthur Wolfe "Rather the strong field that we detect is in gas with little if no star formation, and an interesting implication is that the presence of the magnetic fields is an important reason why star formation is very weak in these types of protogalaxies."
Other Plausible Explanations
According to Wolfe their team has two other plausible explanations for their observations.
1) It may be possible that they are seeing a field toward the central regions of a massive galaxy, since magnetic fields are known to be larger towards the centers of nearby galaxies.
2) It is also possible that the field they have detected has been amplified by a shock wave generated by the collision between two galaxies.
But in either case it has been proved that magnetic fields may be important factors in the evolution of galaxies or we can also say that it is responsible for the low star formation rates detected throughout the gaseous progenitors of young galaxies in the early universe.
The Next Challenge
The next challenge in words of J. Xavier Prochaska, a team member and professor of astronomy at US Santa Cruz, is to observe galaxies throughout the universe.
Major Contributions in Research
Other team members included Regina Jorgenson (UCSD graduate student in physics); Carl Heiles (professor of astronomy at UC Berkeley); Timothy Robishaw (graduate student at Berkeley). This research was funded by National Science Foundation.
Prior Believes
Astronomers believe that magnetic fields within our own Milky Way and other galaxies near milky way, control the rate of star formation and the dynamics of interstellar gas. This magnetic field arose from a slow Dynamo Effect. This magnetic field in these galaxies grew very gradually as they evolved over 5 billion to 10 billion years to their current levels.
But now astronomers have reported that the magnetic field that they have measured in a distant Protogalaxy is at least 10 times greater than average value of Milky Way. This report has been published in October issue of Nature.
According to Arthur Wolfe (Professor of Physics at UC San Diego's Center for Astrophysics and Space Sciences and head of the team), this research is a Complete Surprise. The magnetic field measured is at least an order of magnitude larger than the average value of the magnetic field detected in our own galaxy.
Powerful Radio Telescope and Useful Results
Astronomers used world's largest fully steerable radio telescope for their study known as Robert C. Byrd Green Bank Telescope located in Green Bank, West Virginia. This grand telescope is operated by National Radio Astronomy Observatory of National Science Foundation.
They studied DLA-3C286 protogalaxy located in a region of northern sky.
Magnetic Field outside our galaxy is very less know formerly. Prior to this study astronomers have measured magnetic field of only one nearby galaxy but that field was very weak.
A team of Swiss and American astronomers in July 17 issue of Nature magazine reported that they have found that magnetic field of about 20 distant galaxies were as when the universe was only a third of its current age as they are in the mature galaxies today. This study was done by using bright light from quasars.
Wolfe said those indirect measurements and his team's latest direct measurement of a distant galaxy's magnetic field "do not necessarily cast doubt on the leading theory of magnetic field generation, the mean-field-dynamo model, which predicts that the magnetic field strengths should be much weaker in galaxies in the cosmological past."
Challenge to Dynamo Model
These results have put a challenge before Dynamo Model.
According to Arthur Wolfe "Rather the strong field that we detect is in gas with little if no star formation, and an interesting implication is that the presence of the magnetic fields is an important reason why star formation is very weak in these types of protogalaxies."
Other Plausible Explanations
According to Wolfe their team has two other plausible explanations for their observations.
1) It may be possible that they are seeing a field toward the central regions of a massive galaxy, since magnetic fields are known to be larger towards the centers of nearby galaxies.
2) It is also possible that the field they have detected has been amplified by a shock wave generated by the collision between two galaxies.
But in either case it has been proved that magnetic fields may be important factors in the evolution of galaxies or we can also say that it is responsible for the low star formation rates detected throughout the gaseous progenitors of young galaxies in the early universe.
The Next Challenge
The next challenge in words of J. Xavier Prochaska, a team member and professor of astronomy at US Santa Cruz, is to observe galaxies throughout the universe.
Major Contributions in Research
Other team members included Regina Jorgenson (UCSD graduate student in physics); Carl Heiles (professor of astronomy at UC Berkeley); Timothy Robishaw (graduate student at Berkeley). This research was funded by National Science Foundation.
Water founded on Mars
Phoenix Mars Lander of NASA has recently detected snow fall from Martian Clouds. Soil experiment by this spacecraft has detected interaction between minerals on Mars Surface and liquid water. This new discovery has again raised questions on the presence of water on Mars.
Discovery By Phoenix
This discovery was possible through a large instrument place on Phoenix, which gathers knowledge about the interaction between atmosphere and surface on Mars. This instrument detected that there is snow from clouds at about 4 Kilometers (2.5 miles) above the landing site of Phoenix. However data collected, shows that the snow vaporizing before reaching the surface.
According to Jim Whiteway (Professor of New York University and Lead scientist for the Canadian-supplied Meteorological Station on Phoenix), "It I the first time that such scene is viewed on Mars". Now the scientist are looking for the possibility that snow even reaches to Mars surface.
Other Major Discoveries
Experiment by Phoenix also yielded some other results, like Clues of Calcium Carbonate on Mars surface. Calcium Carbonate is a main composition of Chalk and most important thing is that formation of Calcium Carbonate is possible in the presence of liquid water only.
Peter Smith (Phoenix Principal Investigator of the University of Arizona, Tucson.) says, ""We are still collecting data and have lots of analysis ahead, but we are making good progress on the big questions we set out for ourselves."
Key Aim of Phoenix Mission
The main aim of mission is to find the possibilities of favorable environment on Mars for survival of life. Phoenix landed on Mars surface on May 25, and it has already confirmed that there is a hard subsurface layer at its far northern site which contains water-ice.
Evidence of calcium carbonate in soil samples from trenches dug by the Phoenix robotic arm comes from two laboratory instruments called the Thermal and Evolved Gas Analyzer, or TEGA, and the wet chemistry laboratory of the Microscopy, Electrochemistry and Conductivity Analyzer, or MECA.
This discovery is a next step in confirming presence of water on Mars surface.
Phoenix Mars Lender
Experiments by TEGA and MECA
Evidence of calcium carbonate in soil samples from mars has been found out by the high temperature carbon di-oxide release while experimenting from TEGA. This temperature at which carbon dioxide releases matches the temperature known to decompose calcium carbonate and release carbon dioxide.
TEGA
The MECA evidence came from a buffering effect characteristic of calcium carbonate assessed in wet chemistry analysis of the soil. The measured concentration of calcium was exactly what would be expected for a solution buffered by calcium carbonate.
MECA
Mission Phoenix Extended
Originally Mission Phoenix was planned for three months duration, but its timeline has been extended and it is in its fifth month right now. But now it is facing decline in solar energy and it is expected that it will stop working before the end of 2008. Now the Phoenix team I trying to activate microphone on lander before power ceases.
Mission Lead and Responsibilities
The Phoenix mission is led by Peter Smith at the University of Arizona. Project management is handled by JPL with development partnership by Lockheed Martin in Denver. It is also getting international contributions Canadian Space Agency; University of Neuchatel, Switzerland;; Universities of Copenhagen and Aarhus, Denmark; Max Planck Institute, Germany; and Finnish Meteorological Institute, Finland.
Discovery By Phoenix
This discovery was possible through a large instrument place on Phoenix, which gathers knowledge about the interaction between atmosphere and surface on Mars. This instrument detected that there is snow from clouds at about 4 Kilometers (2.5 miles) above the landing site of Phoenix. However data collected, shows that the snow vaporizing before reaching the surface.
According to Jim Whiteway (Professor of New York University and Lead scientist for the Canadian-supplied Meteorological Station on Phoenix), "It I the first time that such scene is viewed on Mars". Now the scientist are looking for the possibility that snow even reaches to Mars surface.
Other Major Discoveries
Experiment by Phoenix also yielded some other results, like Clues of Calcium Carbonate on Mars surface. Calcium Carbonate is a main composition of Chalk and most important thing is that formation of Calcium Carbonate is possible in the presence of liquid water only.
Peter Smith (Phoenix Principal Investigator of the University of Arizona, Tucson.) says, ""We are still collecting data and have lots of analysis ahead, but we are making good progress on the big questions we set out for ourselves."
Key Aim of Phoenix Mission
The main aim of mission is to find the possibilities of favorable environment on Mars for survival of life. Phoenix landed on Mars surface on May 25, and it has already confirmed that there is a hard subsurface layer at its far northern site which contains water-ice.
Evidence of calcium carbonate in soil samples from trenches dug by the Phoenix robotic arm comes from two laboratory instruments called the Thermal and Evolved Gas Analyzer, or TEGA, and the wet chemistry laboratory of the Microscopy, Electrochemistry and Conductivity Analyzer, or MECA.
This discovery is a next step in confirming presence of water on Mars surface.
Phoenix Mars Lender
Experiments by TEGA and MECA
Evidence of calcium carbonate in soil samples from mars has been found out by the high temperature carbon di-oxide release while experimenting from TEGA. This temperature at which carbon dioxide releases matches the temperature known to decompose calcium carbonate and release carbon dioxide.
TEGA
The MECA evidence came from a buffering effect characteristic of calcium carbonate assessed in wet chemistry analysis of the soil. The measured concentration of calcium was exactly what would be expected for a solution buffered by calcium carbonate.
MECA
Mission Phoenix Extended
Originally Mission Phoenix was planned for three months duration, but its timeline has been extended and it is in its fifth month right now. But now it is facing decline in solar energy and it is expected that it will stop working before the end of 2008. Now the Phoenix team I trying to activate microphone on lander before power ceases.
Mission Lead and Responsibilities
The Phoenix mission is led by Peter Smith at the University of Arizona. Project management is handled by JPL with development partnership by Lockheed Martin in Denver. It is also getting international contributions Canadian Space Agency; University of Neuchatel, Switzerland;; Universities of Copenhagen and Aarhus, Denmark; Max Planck Institute, Germany; and Finnish Meteorological Institute, Finland.
Amazing research on Learning of Human Beings
According to a recent research it has been proved that Eight-year-old children have a different learning strategy from twelve-year-olds and adults. While Eight-year-olds learn primarily from positive feedback such as 'Well done!', negative feedback 'Got it wrong this time' hardly effects their learning. Opposite to that Twelve-year-olds are better able to process negative feedback, and can use it to learn from their mistakes. Adults have the same ability but they do it more efficiently.
Cognitive Control in Brain
According to Dr. Eveline Crone, psychologist in Leiden Brain and Cognition Lab "Eight-year-olds respond disproportionately inaccurately to negative feedback. Dr. Crone and her colleagues performed a research named fMRI Research which shows that this difference can be observed particularly in the areas of the brain responsible for cognitive control, located in the Cerebral Cortex.
According to this research it has been demonstrated that, In children of eight and nine, these areas of the brain react strongly to positive feedback and scarcely respond at all to negative feedback. While in children of 12 and 13, and in adults, the opposite is the case. The 'Control Centers' in their brain are more strongly activated by negative feedback and much less by positive feedback.
Unique Three-Way Division
Generally in these types of experiments the comparison is generally made between children and adults. But in this experiment Dr. Crone and her colleagues made three different age groups: Children of 8 to 9 years | Children of 11 to 12 years and adults aged between 18 and 25 years. This three-way division had been made first time in such experiments.
Unexpected Results
Dr. Crone and their team were surprised at the results. According to Dr. Crone 'We had expected that the brains of eight-year-olds would function in exactly the same way as the brains of twelve-year-olds, but maybe not quite so well. Children learn the whole time, so this new knowledge can have major consequences for people wanting to teach children: how can you best relay instructions to eight- and twelve-year-olds?' '
Experiment
In the experiment, the children of both age groups and adults aged 18 to 25 were engaged in a computer task while they lay in the MRI scanner. The task was about to discover rules. If they did this correctly, a tick appeared on the screen, otherwise a cross appeared. During this test MRI scans captured records of which parts of the brain were activated.
Learning From Mistakes Is Difficult
After this experiment Dr. Crone was able to compare the fMRI results with the existing knowledge about child development. It has been known that "Young children respond better to reward than to punishment." Therefore It is sure that, Learning from mistakes is more complex and difficult than carrying on in the same way as before.
Still Some Unanswered Questions
While this experiment is very significant regarding the development of children, there are some unanswered questions till now. Such as "This difference between eight- and twelve-year-olds the result of experience, or does it have to do with the way the brain develops? Some researchers say it a combination of the brain maturing and experience. May be some time in future this questions will be solved by any such research.
Cognitive Control in Brain
According to Dr. Eveline Crone, psychologist in Leiden Brain and Cognition Lab "Eight-year-olds respond disproportionately inaccurately to negative feedback. Dr. Crone and her colleagues performed a research named fMRI Research which shows that this difference can be observed particularly in the areas of the brain responsible for cognitive control, located in the Cerebral Cortex.
According to this research it has been demonstrated that, In children of eight and nine, these areas of the brain react strongly to positive feedback and scarcely respond at all to negative feedback. While in children of 12 and 13, and in adults, the opposite is the case. The 'Control Centers' in their brain are more strongly activated by negative feedback and much less by positive feedback.
Unique Three-Way Division
Generally in these types of experiments the comparison is generally made between children and adults. But in this experiment Dr. Crone and her colleagues made three different age groups: Children of 8 to 9 years | Children of 11 to 12 years and adults aged between 18 and 25 years. This three-way division had been made first time in such experiments.
Unexpected Results
Dr. Crone and their team were surprised at the results. According to Dr. Crone 'We had expected that the brains of eight-year-olds would function in exactly the same way as the brains of twelve-year-olds, but maybe not quite so well. Children learn the whole time, so this new knowledge can have major consequences for people wanting to teach children: how can you best relay instructions to eight- and twelve-year-olds?' '
Experiment
In the experiment, the children of both age groups and adults aged 18 to 25 were engaged in a computer task while they lay in the MRI scanner. The task was about to discover rules. If they did this correctly, a tick appeared on the screen, otherwise a cross appeared. During this test MRI scans captured records of which parts of the brain were activated.
Learning From Mistakes Is Difficult
After this experiment Dr. Crone was able to compare the fMRI results with the existing knowledge about child development. It has been known that "Young children respond better to reward than to punishment." Therefore It is sure that, Learning from mistakes is more complex and difficult than carrying on in the same way as before.
Still Some Unanswered Questions
While this experiment is very significant regarding the development of children, there are some unanswered questions till now. Such as "This difference between eight- and twelve-year-olds the result of experience, or does it have to do with the way the brain develops? Some researchers say it a combination of the brain maturing and experience. May be some time in future this questions will be solved by any such research.
Robot adapted to Surrounding
Robotic Engineers at MIT Humanoid Robotics Group have developed a robot which is capable of adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
This next generation robot is named as DOMO. Engineers have placed cameras inside robot's eyes which enables it to see and adapt to his surroundings. There are about 29 motors, equipped with computer chips run off a dozen computers that continuously update information.
MOTIVATION BEHIND DOMO
According to Aaron Edsinger, Engineer at MIT Humanoid Robotics Group, the main motivation behind developing DOMO is to develop a system that can assist people with everyday chores, everyday life, everyday work.
Robotic Engineers at MIT Humanoid Robotics Group have developed a robot which is capable of adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
DOMO can visually sense the surrounding conditions and adapt its functioning according to situations. For example, "it can learn about the size of an object and decide how to place it on a shelf."
HOW IT IS DIFFERENT
Although there are many humanoid robots that are being developed around the world, DOMO is different as it can take the lead and adapt to a situation. Suppose "If the robot drops something in the middle of doing a task, it can stop and try and pick it up again and start over."
This amazing quality makes it more helpful for human assistance.
HOW DOMO WORKS
1) Domo can see everything with the help of its large blue eyes that are equipped with powerful cameras that scan the entire surrounding.
2) These cameras then feed visual information to 12 computers that are used to analyze the input and decide the focusing point. This is a very important step, because for a robot to function in a real-world human environment, such as a kitchen, it must be able to ignore clutter and focus only on certain stimuli.
3) The visual system of DOMO is attuned to unexpected motion. For instance, locating human faces is critical for social interaction and people are often in motion.
4) When DOMO spots a motion that looks like a face, it locks its gaze onto it. Once Domo's gaze is captured, the human can issue verbal commands such as "to find a shelf".
5) The robot will scan the room for a shelf and then reach out a hand to touch the object to make sure it is really there.
6) If an object is then placed in its hand -- such as a bag of coffee beans -- the robot will reach up and place the object on the shelf.
adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
This next generation robot is named as DOMO. Engineers have placed cameras inside robot's eyes which enables it to see and adapt to his surroundings. There are about 29 motors, equipped with computer chips run off a dozen computers that continuously update information.
MOTIVATION BEHIND DOMO
According to Aaron Edsinger, Engineer at MIT Humanoid Robotics Group, the main motivation behind developing DOMO is to develop a system that can assist people with everyday chores, everyday life, everyday work.
Robotic Engineers at MIT Humanoid Robotics Group have developed a robot which is capable of adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
IT CAN ALSO FEEL WEIGHT
DOMO can also observe the size and weight of any object that is placed in its hand. For this, DOMO wiggles it a little. This movement is very minor but is very important for the robot's ability, which helps it to accurately place it on the shelf. DOMO is programmed such that it can learn about the size of an object by focusing on its tip, such as the cap of a water bottle. When the robot wiggles the tip back and forth, it can figure out how big the bottle is and can decide how to transfer it from hand to hand, or to place it on a shelf.
Domo can also sense when a human is touching it, thanks to springs in its arms, hands and neck that can sense force and response to it. If too much force is applied, the robot will voice its displeasure by saying..... "ouch!"
This next generation robot is named as DOMO. Engineers have placed cameras inside robot's eyes which enables it to see and adapt to his surroundings. There are about 29 motors, equipped with computer chips run off a dozen computers that continuously update information.
MOTIVATION BEHIND DOMO
According to Aaron Edsinger, Engineer at MIT Humanoid Robotics Group, the main motivation behind developing DOMO is to develop a system that can assist people with everyday chores, everyday life, everyday work.
Robotic Engineers at MIT Humanoid Robotics Group have developed a robot which is capable of adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
DOMO can visually sense the surrounding conditions and adapt its functioning according to situations. For example, "it can learn about the size of an object and decide how to place it on a shelf."
HOW IT IS DIFFERENT
Although there are many humanoid robots that are being developed around the world, DOMO is different as it can take the lead and adapt to a situation. Suppose "If the robot drops something in the middle of doing a task, it can stop and try and pick it up again and start over."
This amazing quality makes it more helpful for human assistance.
HOW DOMO WORKS
1) Domo can see everything with the help of its large blue eyes that are equipped with powerful cameras that scan the entire surrounding.
2) These cameras then feed visual information to 12 computers that are used to analyze the input and decide the focusing point. This is a very important step, because for a robot to function in a real-world human environment, such as a kitchen, it must be able to ignore clutter and focus only on certain stimuli.
3) The visual system of DOMO is attuned to unexpected motion. For instance, locating human faces is critical for social interaction and people are often in motion.
4) When DOMO spots a motion that looks like a face, it locks its gaze onto it. Once Domo's gaze is captured, the human can issue verbal commands such as "to find a shelf".
5) The robot will scan the room for a shelf and then reach out a hand to touch the object to make sure it is really there.
6) If an object is then placed in its hand -- such as a bag of coffee beans -- the robot will reach up and place the object on the shelf.
adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
This next generation robot is named as DOMO. Engineers have placed cameras inside robot's eyes which enables it to see and adapt to his surroundings. There are about 29 motors, equipped with computer chips run off a dozen computers that continuously update information.
MOTIVATION BEHIND DOMO
According to Aaron Edsinger, Engineer at MIT Humanoid Robotics Group, the main motivation behind developing DOMO is to develop a system that can assist people with everyday chores, everyday life, everyday work.
Robotic Engineers at MIT Humanoid Robotics Group have developed a robot which is capable of adapting to situations so that it can assist people with everyday chores, everyday life and everyday work.
IT CAN ALSO FEEL WEIGHT
DOMO can also observe the size and weight of any object that is placed in its hand. For this, DOMO wiggles it a little. This movement is very minor but is very important for the robot's ability, which helps it to accurately place it on the shelf. DOMO is programmed such that it can learn about the size of an object by focusing on its tip, such as the cap of a water bottle. When the robot wiggles the tip back and forth, it can figure out how big the bottle is and can decide how to transfer it from hand to hand, or to place it on a shelf.
Domo can also sense when a human is touching it, thanks to springs in its arms, hands and neck that can sense force and response to it. If too much force is applied, the robot will voice its displeasure by saying..... "ouch!"
NEXI - Robot with facial expressions
A latest invention by MIT Media Lab is a new robot that is able to show various facial expressions such as 'slanting its eyebrows in anger', or 'raise them in surprise', and show a wide assortment of facial expressions while communicating with people.
This latest achievement in the field of Robotics is named NEXI as it is framed as the next generation robots which is aimed for a range of applications for personal robots and human-robot teamwork.
DESIGNING
The head and face of NEXI were designed by Xitome Design which is a innovative designing and development company that specializes in robotic design and development. The expressive robotics started with a neck mechanism sporting 4 degrees of freedom (DoF) at the base, plus pan-tilt-yaw of the head itself. The mechanism has been constructed to time the movements so they mimic human speed. The face of NEXI has been specially designed to use gaze, eyebrows, eyelids and an articulate mandible which helps in expressing a wide range of different emotions.
The chassis of NEXI is also advanced. It has been developed by the Laboratory for Perceptual Robotics UMASS (University of Massachusetts), Amherst. This chassis is based on the uBot5 mobile manipulator. The mobile base can balance dynamically on two wheels. The arms of NEXI can pick up a weight of up to 10 pounds and the plastic covering of the chassis can detect any kind of human touch.
CYNTHIA BREAZEAL: HEAD OF THE PROJECT
This project was headed by Media Lab's Cynthia Breazeal, a well known robotics expert famous for earlier expressive robots such as Kismet. She is an Associate Professor of Media Arts and Sciences at the MIT. She named her new product as an MDS (mobile, dextrous, social) robot.
FEATURES OF NEXI
Except a wide range of facial expressions, Nexi has many other features. It has self-balancing wheels like the Segway transporter, to ultimately ride on. Currently it uses an additional set of supportive wheels to operate as a statically stable platform in its early stage of development. It has hands which can be used to manipulate objects, eyes (video cameras), ears (an array of microphones), and a 3-D infrared camera and laser rangefinder which support real-time tracking of objects, people and voices as well as indoor navigation.
Black Hole Mystery Solved
This latest achievement in the field of Robotics is named NEXI as it is framed as the next generation robots which is aimed for a range of applications for personal robots and human-robot teamwork.
DESIGNING
The head and face of NEXI were designed by Xitome Design which is a innovative designing and development company that specializes in robotic design and development. The expressive robotics started with a neck mechanism sporting 4 degrees of freedom (DoF) at the base, plus pan-tilt-yaw of the head itself. The mechanism has been constructed to time the movements so they mimic human speed. The face of NEXI has been specially designed to use gaze, eyebrows, eyelids and an articulate mandible which helps in expressing a wide range of different emotions.
The chassis of NEXI is also advanced. It has been developed by the Laboratory for Perceptual Robotics UMASS (University of Massachusetts), Amherst. This chassis is based on the uBot5 mobile manipulator. The mobile base can balance dynamically on two wheels. The arms of NEXI can pick up a weight of up to 10 pounds and the plastic covering of the chassis can detect any kind of human touch.
CYNTHIA BREAZEAL: HEAD OF THE PROJECT
This project was headed by Media Lab's Cynthia Breazeal, a well known robotics expert famous for earlier expressive robots such as Kismet. She is an Associate Professor of Media Arts and Sciences at the MIT. She named her new product as an MDS (mobile, dextrous, social) robot.
FEATURES OF NEXI
Except a wide range of facial expressions, Nexi has many other features. It has self-balancing wheels like the Segway transporter, to ultimately ride on. Currently it uses an additional set of supportive wheels to operate as a statically stable platform in its early stage of development. It has hands which can be used to manipulate objects, eyes (video cameras), ears (an array of microphones), and a 3-D infrared camera and laser rangefinder which support real-time tracking of objects, people and voices as well as indoor navigation.
Black Hole Mystery Solved
4G Technology
Fourth Generation (4G) mobiles
4G also called as Fourth-Generation Communications System, is a term used to describe the next step in wireless communications. A 4G system can provide a comprehensive IP solution where voice, data and streamed multimedia can be provided to users on an "Anytime, Anywhere" basis. The data transfer rates are also much higher than previous generations.
The main objectives of 4G are:
1)4G will be a fully IP-based integrated system.
2)This will be capable of providing 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors.
3)It can provide premium quality and high security.
4)4G offer all types of services at an affordable cost.
4G is developed to provide high quality of service (QoS) and rate requirements set by forthcoming applications such as wireless broadband access, Multimedia Messaging, Video Chat, Mobile TV, High definition TV content, DVB, minimal service like voice and data, and other streaming services.
4G technology allow high-quality smooth video transmission. It will enable fast downloading of full-length songs or music pieces in real time.
The business and popularity of 4Gmobiles is predicted to be very vast. On an average, by 2009, this 4Gmobile market will be over $400B and it will dominate the wireless communications, and its converged system will replace most conventional wireless infrastructure.
Data Rates For 4G:
The downloading speed for mobile Internet connections is from 9.6 kbit/s for 2G cellular at present. However, in actual use the data rates are usually slower, especially in crowded areas, or when there is congestion in network.
4G mobile data transmission rates are planned to be up to 20 megabits per second which means that it will be about 10-20 times faster than standard ASDL services.
In terms of connection seeds, 4G will be about 200 times faster than present 2G mobile data rates, and about 10 times faster than 3G broadband mobile. 3G data rates are currently 2Mbit/sec, which is very fast compared to 2G's 9.6Kbit/sec.
4G also called as Fourth-Generation Communications System, is a term used to describe the next step in wireless communications. A 4G system can provide a comprehensive IP solution where voice, data and streamed multimedia can be provided to users on an "Anytime, Anywhere" basis. The data transfer rates are also much higher than previous generations.
The main objectives of 4G are:
1)4G will be a fully IP-based integrated system.
2)This will be capable of providing 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors.
3)It can provide premium quality and high security.
4)4G offer all types of services at an affordable cost.
4G is developed to provide high quality of service (QoS) and rate requirements set by forthcoming applications such as wireless broadband access, Multimedia Messaging, Video Chat, Mobile TV, High definition TV content, DVB, minimal service like voice and data, and other streaming services.
4G technology allow high-quality smooth video transmission. It will enable fast downloading of full-length songs or music pieces in real time.
The business and popularity of 4Gmobiles is predicted to be very vast. On an average, by 2009, this 4Gmobile market will be over $400B and it will dominate the wireless communications, and its converged system will replace most conventional wireless infrastructure.
Data Rates For 4G:
The downloading speed for mobile Internet connections is from 9.6 kbit/s for 2G cellular at present. However, in actual use the data rates are usually slower, especially in crowded areas, or when there is congestion in network.
4G mobile data transmission rates are planned to be up to 20 megabits per second which means that it will be about 10-20 times faster than standard ASDL services.
In terms of connection seeds, 4G will be about 200 times faster than present 2G mobile data rates, and about 10 times faster than 3G broadband mobile. 3G data rates are currently 2Mbit/sec, which is very fast compared to 2G's 9.6Kbit/sec.
Saturday, February 19, 2011
LUNAR SOLAR POWER
ABSTRACT
Out of all the renewable and non-polluting sources solar power become the most the primary source of commercial power for every one in the world to achieve the same high standard of living. Over the past 200 years the developed nations have vastly increased their creation of per capita income compared to the other nations. In parallel, the developed nations increased the use of commercial thermal power to ~6.9Kwt/person. In fact, most people in the developing nations use much less commercial thermal power and most have little (or) no access to electric power. By the year 2050, people will require at least 20,000 GWe of power. This requires approximately 60,000 GWt of conventional thermal power generation. Such enormous thermal energy consumption will exhaust economical
recoverable deposits of coal, shale, oil, natural gas, uranium and thorium. As a result, of conventional systems become useless. Terrestrial renewable systems are always captive to global climate change induced by volcanoes, natural variation in regional climate, industrial haze and
possibly even microclimates induced by large area collectors. Over the 21-st century, a global stand -alone system for renewable power would cost thousand of trillions of dollars to build and maintain. Energy costs could consume most of the world's wealth. We need a power system that is independent of earth's biosphere and provides an abundant energy at low cost. To do this man -kind must collect dependable solar power in space and reliably send it to receivers on earth. The MOON is the KEY.
Present and Future Power Scenario
In 1975 Goeller and Weinberg published a fundamental paper on the relation of commercial power to economic prosperity. They estimated that an advanced economy could provide the full range of Goods and services to its population with 6kWt/person. As technology advances, the goods and services could be provided by ~2 kWe/person of electric power. There will be approximately 10 billion people in 2050.They must be supplied with ~6 kWt/person or ~2 kWe/person in order to achieve energy and economic prosperity.
Present world capacity for commercial power must increase by a factor of ~5 by 2050 to 60 kWt or ~20 TWe (T=1012). Output must be maintained indefinitely. Conventional power systems are too expensive for the Developing Nations. Six kilowatts of thermal power now costs ~1,400 $/Y-person. This is ~50% of the average per capita income within the Developing Nations. Other major factors include the limited availability of fossil and nuclear fuels (4,000,000 GWt-Y) and the relatively low economic output from thermal energy (~ 0.25 $/kWt-h). Humans must transition to solar energy during first part of the 21st Century to extend the newly emerging world prosperity. However, solar and wind are intermittent and diffuse. Their energy output is too expensive to collect, store, and dependably distribute.
Lunar Solar Power Generation
Two general concepts have been proposed for delivering solar power to Earth from space. In one, Peter Glaser of Arthur D. Little, Inc. (Cambridge, MA), proposed in 1968 that a huge satellite in geosynchronous orbit around Earth could dependably gather solar power in space. In the second concept figure (1), discussed here, solar power would be collected on the moon. In both ideas, many different beams of 12cm wavelength microwaves would deliver power to receivers at sites located worldwide. Each receiver would supply commercial power to a given region. Such a receiver, called a rectenna, would consist of a large field of small rectifying antennas. A beam with a maximum intensity of less than 20% of noontime sunlight would deliver about 200 W to its local electric grid for every square meter of rectenna area.
Unlike sunlight, microwaves pass through rain, clouds, dust, and smoke. In both scenarios, power can be supplied to the rectenna at night Several thousand individual rectennas strategically located around the globe, with a total area of 100,000 km2, could continuously provide the 20 TW of electric power, or 2 kW per person, required for a prosperous world of 10 billion people in 2050. This surface area is 5% of the surface area that would be needed on Earth to generate 20 TW using the most advanced terrestrial solar-array technology of similar average capacity now envisioned. Rectennas are projected to cost approximately $0.004/kWeoh, which is less than one-tenth of the current cost of most commercial electric energy. This new electric power would be provided without any significant use of Earth's resources several types of solar power satellites have been proposed. They are projected, over 30 years, to deliver approximately 10,000 kWoh of electric energy to Earth for each kilogram of mass in orbit around theplanet.
To sell electric energy at $0.01/ kWoh, less than $60 could be expended per kilogram to buy the components of the power satellites, ship them into space, assemble and maintain them, decommission the satellites, and finance all aspects of the space operations. To achieve this margin, launch and fabrication costs would have to be lowered by a factor of 10,000. Power prosperity would require a fleet of approximately 6,000 huge, solar-power satellites. The fleet would have more than 330,000 km2 of solar arrays on-orbit and a mass exceeding 300 million tones. By comparison, the satellite payloads and rocket bodies now in Earth geosynchronous orbit have a collective surface area of about 0.1 km2. The mass launch rate for a fleet of power satellites would have to be 40,000 times that achieved during the Apollo era by both the United States and the Soviet Union. A many decade development program would be required before commercial development could be considered.
Lunar Solar Collectors
Fortunately, in the Lunar Solar Power (LSP) System, an appropriate, natural satellite is available for commercial development. The surface of Earth's moon receives 13,000 TW of absolutely predictable solar power. The LSP System uses 10 to 20 pairs of bases-one of each pair on the eastern edge and the other on the western edge of the moon, as seen from Earth-to collect on the order of 1% of the solar power reaching the lunar surface. The collected sunlight is converted to many low intensity beams of microwaves and directed to rectennas on Earth. Each rectenna converts the microwave power to electricity that is fed into the local electric grid. The system could easily deliver the 20 TW or more of electric power required by 10 billion people. Adequate knowledge of the moon and practical technologies has been available since the late 1970s to collect this power and beam it to Earth. Successful Earth-moon power beams are already in use by the Arecibo planetary radar, operating from Puerto Rico. This radio telescope periodically images the moon for mapping and other scientific studies with a radar beam whose intensity in Earth's atmosphere is 10% of the maximum proposed for the LSP System. Each lunar power base would be augmented by fields of solar converters located on the back side of the moon, 500 to 1,000 km beyond each visible edge and connected to the earthward power bases by electric transmission lines.
The moon receives sunlight continuously except during a full lunar eclipse, which occurs approximately once a year and lasts for less than three hours. Energy stored on Earth as hydrogen, synthetic gas, dammed water, and other forms could be released during a short eclipse. Each lunar power base consists of tens of thousands ofpower plots figure (2) distributed in an elliptical area to form fully segmented, phased-array radar that is solar-powered. Each demonstration power plot consists of four major subsystems. Solar cells collect sunlight, and buried electrical wires carry the solar energy as electric power to microwave generators.
These devices convert the solar electricity to microwaves of the correct phase and amplitude and then send the microwaves to screens that reflect microwave beams toward Earth. Rectennas located on Earth between 60º N and 60º S can receive power directly from the moon approximately 8 hours a day. Power could be received anywhere on Earth via a fleet of relay satellites in high inclination, eccentric orbits around Earth figure (1). A given relay satellite receives a power beam from the moon and retransmits multiple beams to several rectennas on Earth required by an alternative operation. This enables the region around each rectenna to receive power 24 hours a day. The relay satellites would require less than 1% of the surface area needed by a fleet of solar-power satellites in orbit around Earth. Synthetic-aperture radars, such as those flown on the Space Shuttle, have demonstrated the feasibility of multibeam transmission of pulsed power directed to Earth from orbit. Relay satellites may reflect the beam or may receive the beam, convert it in frequency and phasing and then, transmit a new beam to the rectenna. A retransmitter satellite may generate several beam and simultaneously service several rectennas. The orbital reflector and retransmitter satellites minimize the need on earth for long distance power lines. Relay satellites also minimize the area and mass of power handling equipments in orbit around earth. There by reducing the hazards of orbital debris to space vehicles and satellites.
Fabrication of Thin Film Crystalline Silicon Solar Cells
The silicon film is a proprietary process, and only a very general process is designed. The generic process consists of ceramic formation, metallurgical barrier formation, polycrystalline layer deposition, emitter diffusion and contact fabrication. The conductive ceramic substrate is fabricated from selected low-cost materials. The metallurgical barrier prevents the substrate impurities from entering and contaminating the active thin silicon layer. The randomly textured andhighly reflecting metallurgical barrier improves light trapping. A suitable p- type doped 30 - 100micro-cm active layer is deposited from a liquid solution. Phosphorus and aluminium impurity gathering are used for bulk quality improvement. Cells with large areas of 240, 300 and 700 cm2 are developed. A cell with an area of 675 cm2 has demonstrated the record efficiency of 11.6 -17.7%. The waste products present in the lunar surface are silicon, iron, TiO2, etc. These products can be used as raw materials for solar cell fabrication. A special compound called anorthite is used for extracting the above said components. Carbothermal reduction of anorthite,
Carbon compounds can also be used to extract Oxygen, Fe, and TiO2 from Lunar Ilemenite. The iron is used for interconnect and TiO2 for anti reflect.
Microwave
For direct microwave wireless power transmission to the surface of the earth, a limited range of transmission frequencies is suitable. Frequencies above 6 GHz are subject to atmospheric attenuation and absorption, while frequencies below 2 GHz require excessively large apertures for transmission and reception. Efficient transmission requires the beam have a Gaussian power density. Transmission efficiency çb for Gaussian beams is related to the aperture sizes of the transmitting and receiving antennas: çb ~ 1- exp (-ô2) and ô = ðDtDr/ (4ëR) Where Dt is the transmitting array diameter, Dr is the receiving array diameter, çb .is the wavelength of transmission and R is the range of transmission. Frequencies other than 2.45 GHz, particularly 5.8 GHz and 35 GHz are being given greater attention as candidates for microwave wireless power transmission in studies and experiments. The mass and size of components and systems for the higher frequencies are attractive. However, the component efficiencies are less than for 2.45 GHz, and atmospheric attenuation, particularly with rain, is greater.
Cost Forecasting
To achieve low unit cost of energy, the lunar portions of the LSP System are made primarily of lunar derived components. Factories, fixed and mobile, are transported from the Earth to the Moon. High output greatly reduces the impact of high transportation costs from the Earth to the Moon. On the Moon the factories produce 100s to 1,000s of times their own mass in LSP components. Construction and operation of the rectennas on Earth constitutes greater than 90% of the engineering costs. Any handful of lunar dust and rocks contains at least 20% silicon, 40% oxygen, and 10% metals (iron, aluminum, etc.). Lunar dust can be used directly as thermal, electrical, and radiation shields, converted into glass, fiberglass, and ceramics, and processed chemically into its elements. Solar cells, electric wiring, some micro-circuitry components, and the reflector screens can be made out of lunar materials. Soil handling and glass production are the primary industrial operations. Selected micro circuitry can be supplied from Earth. Use of the Moon as a source of construction materials and as the platform on which to gather solar energy eliminates the need to build extremely large platforms in space. LSP components can be manufactured directly from the lunar materials and then immediately placed on site. This eliminates most of the packaging, transport, and reassembly of components delivered from Earth or the Moon to deep space. There is no need for a large manufacturing facility in deep space. The LSP System is the only likely means to provide 20 TWe of affordable electric power to Earth by 2050. According to criswell in the year 1996 lunar solar power reference design for 20,000GWe Its also noted that the total mass investment for electricity from lunar solar energy is less than for Terrestrial solar energy systems.
Terrestrial Thermal power system - 310,000tones/GWe.
Terrestrial photo voltaic -430,000tones/GWe.
Lunar solar power - 52,000 tones / GWe.
Merits of LSP
In technical and other aspects there are two reasons for which we prefer LSP are:Unlike earth, the, moon is the ideal environment for large area solar converters.
The solar flux to the lunar surface is predictable and dependable.
>> There is no air or water to degrade large area thin film devices.
>> Solar collectors can be made that are unaffected by decades of exposure to solar cosmic rays and the solar wind.
>> Sensitive circuitry and wiring can be buried under a few- tens of centimeters of lunar soil, and completely protected against solar radiations
temperature extremes. Secondly, virtually all the LSP components can be made from local lunar materials.
>> The high cost of transportation to and from the moon is cancelled out by sending machines and small factors to the moon that produce hundreds to several thousand times there own mass in components and supplies.
>> Lunar materials will be used to reduce the cost of transportation between the earth and the moon and provide supplies.
Additional Features of LSP
The design and demonstration of robots to assemble the LSP components and construct the power plots can be done in parallel. The crystalline silicon solar cells can be used in the design of robots, which will further decrease the installation cost.
Economical Advantages of LSP and Crystalline Silicon Solar Cell
>> Crystalline silicon solar cells almost completely dominate world - wide solar cell production.
>> Excellent stability and reliability plus continuous development in cell structure and processing make it very likely that
crystalline silicon cells will remain in this position for the next ten years.
>> Laboratory solar cells, processed by means of sophisticated micro - electronic techniques using high quality Fe-Si substrate have approached energy conversionefficienciesof24%
1) Solar converter.
2). Microwave generator.
3). Microwave reflector.
4). Mobile factory.
5). Assembly units.
6). Habitat / Manufacturing units.
Conclusion
A global stand -alone system for renewable power would cost thousand of trillions of dollars to build and maintain. Energy costs could consume most of the world's wealth. We need a power system that is independent of earth's biosphere and provides an abundant energy at low cost. To do this man -kind must collect dependable solar power in space and reliably send it to receivers on earth. The MOON is the KEY.
Out of all the renewable and non-polluting sources solar power become the most the primary source of commercial power for every one in the world to achieve the same high standard of living. Over the past 200 years the developed nations have vastly increased their creation of per capita income compared to the other nations. In parallel, the developed nations increased the use of commercial thermal power to ~6.9Kwt/person. In fact, most people in the developing nations use much less commercial thermal power and most have little (or) no access to electric power. By the year 2050, people will require at least 20,000 GWe of power. This requires approximately 60,000 GWt of conventional thermal power generation. Such enormous thermal energy consumption will exhaust economical
recoverable deposits of coal, shale, oil, natural gas, uranium and thorium. As a result, of conventional systems become useless. Terrestrial renewable systems are always captive to global climate change induced by volcanoes, natural variation in regional climate, industrial haze and
possibly even microclimates induced by large area collectors. Over the 21-st century, a global stand -alone system for renewable power would cost thousand of trillions of dollars to build and maintain. Energy costs could consume most of the world's wealth. We need a power system that is independent of earth's biosphere and provides an abundant energy at low cost. To do this man -kind must collect dependable solar power in space and reliably send it to receivers on earth. The MOON is the KEY.
Present and Future Power Scenario
In 1975 Goeller and Weinberg published a fundamental paper on the relation of commercial power to economic prosperity. They estimated that an advanced economy could provide the full range of Goods and services to its population with 6kWt/person. As technology advances, the goods and services could be provided by ~2 kWe/person of electric power. There will be approximately 10 billion people in 2050.They must be supplied with ~6 kWt/person or ~2 kWe/person in order to achieve energy and economic prosperity.
Present world capacity for commercial power must increase by a factor of ~5 by 2050 to 60 kWt or ~20 TWe (T=1012). Output must be maintained indefinitely. Conventional power systems are too expensive for the Developing Nations. Six kilowatts of thermal power now costs ~1,400 $/Y-person. This is ~50% of the average per capita income within the Developing Nations. Other major factors include the limited availability of fossil and nuclear fuels (4,000,000 GWt-Y) and the relatively low economic output from thermal energy (~ 0.25 $/kWt-h). Humans must transition to solar energy during first part of the 21st Century to extend the newly emerging world prosperity. However, solar and wind are intermittent and diffuse. Their energy output is too expensive to collect, store, and dependably distribute.
Lunar Solar Power Generation
Two general concepts have been proposed for delivering solar power to Earth from space. In one, Peter Glaser of Arthur D. Little, Inc. (Cambridge, MA), proposed in 1968 that a huge satellite in geosynchronous orbit around Earth could dependably gather solar power in space. In the second concept figure (1), discussed here, solar power would be collected on the moon. In both ideas, many different beams of 12cm wavelength microwaves would deliver power to receivers at sites located worldwide. Each receiver would supply commercial power to a given region. Such a receiver, called a rectenna, would consist of a large field of small rectifying antennas. A beam with a maximum intensity of less than 20% of noontime sunlight would deliver about 200 W to its local electric grid for every square meter of rectenna area.
Unlike sunlight, microwaves pass through rain, clouds, dust, and smoke. In both scenarios, power can be supplied to the rectenna at night Several thousand individual rectennas strategically located around the globe, with a total area of 100,000 km2, could continuously provide the 20 TW of electric power, or 2 kW per person, required for a prosperous world of 10 billion people in 2050. This surface area is 5% of the surface area that would be needed on Earth to generate 20 TW using the most advanced terrestrial solar-array technology of similar average capacity now envisioned. Rectennas are projected to cost approximately $0.004/kWeoh, which is less than one-tenth of the current cost of most commercial electric energy. This new electric power would be provided without any significant use of Earth's resources several types of solar power satellites have been proposed. They are projected, over 30 years, to deliver approximately 10,000 kWoh of electric energy to Earth for each kilogram of mass in orbit around theplanet.
To sell electric energy at $0.01/ kWoh, less than $60 could be expended per kilogram to buy the components of the power satellites, ship them into space, assemble and maintain them, decommission the satellites, and finance all aspects of the space operations. To achieve this margin, launch and fabrication costs would have to be lowered by a factor of 10,000. Power prosperity would require a fleet of approximately 6,000 huge, solar-power satellites. The fleet would have more than 330,000 km2 of solar arrays on-orbit and a mass exceeding 300 million tones. By comparison, the satellite payloads and rocket bodies now in Earth geosynchronous orbit have a collective surface area of about 0.1 km2. The mass launch rate for a fleet of power satellites would have to be 40,000 times that achieved during the Apollo era by both the United States and the Soviet Union. A many decade development program would be required before commercial development could be considered.
Lunar Solar Collectors
Fortunately, in the Lunar Solar Power (LSP) System, an appropriate, natural satellite is available for commercial development. The surface of Earth's moon receives 13,000 TW of absolutely predictable solar power. The LSP System uses 10 to 20 pairs of bases-one of each pair on the eastern edge and the other on the western edge of the moon, as seen from Earth-to collect on the order of 1% of the solar power reaching the lunar surface. The collected sunlight is converted to many low intensity beams of microwaves and directed to rectennas on Earth. Each rectenna converts the microwave power to electricity that is fed into the local electric grid. The system could easily deliver the 20 TW or more of electric power required by 10 billion people. Adequate knowledge of the moon and practical technologies has been available since the late 1970s to collect this power and beam it to Earth. Successful Earth-moon power beams are already in use by the Arecibo planetary radar, operating from Puerto Rico. This radio telescope periodically images the moon for mapping and other scientific studies with a radar beam whose intensity in Earth's atmosphere is 10% of the maximum proposed for the LSP System. Each lunar power base would be augmented by fields of solar converters located on the back side of the moon, 500 to 1,000 km beyond each visible edge and connected to the earthward power bases by electric transmission lines.
The moon receives sunlight continuously except during a full lunar eclipse, which occurs approximately once a year and lasts for less than three hours. Energy stored on Earth as hydrogen, synthetic gas, dammed water, and other forms could be released during a short eclipse. Each lunar power base consists of tens of thousands ofpower plots figure (2) distributed in an elliptical area to form fully segmented, phased-array radar that is solar-powered. Each demonstration power plot consists of four major subsystems. Solar cells collect sunlight, and buried electrical wires carry the solar energy as electric power to microwave generators.
These devices convert the solar electricity to microwaves of the correct phase and amplitude and then send the microwaves to screens that reflect microwave beams toward Earth. Rectennas located on Earth between 60º N and 60º S can receive power directly from the moon approximately 8 hours a day. Power could be received anywhere on Earth via a fleet of relay satellites in high inclination, eccentric orbits around Earth figure (1). A given relay satellite receives a power beam from the moon and retransmits multiple beams to several rectennas on Earth required by an alternative operation. This enables the region around each rectenna to receive power 24 hours a day. The relay satellites would require less than 1% of the surface area needed by a fleet of solar-power satellites in orbit around Earth. Synthetic-aperture radars, such as those flown on the Space Shuttle, have demonstrated the feasibility of multibeam transmission of pulsed power directed to Earth from orbit. Relay satellites may reflect the beam or may receive the beam, convert it in frequency and phasing and then, transmit a new beam to the rectenna. A retransmitter satellite may generate several beam and simultaneously service several rectennas. The orbital reflector and retransmitter satellites minimize the need on earth for long distance power lines. Relay satellites also minimize the area and mass of power handling equipments in orbit around earth. There by reducing the hazards of orbital debris to space vehicles and satellites.
Fabrication of Thin Film Crystalline Silicon Solar Cells
The silicon film is a proprietary process, and only a very general process is designed. The generic process consists of ceramic formation, metallurgical barrier formation, polycrystalline layer deposition, emitter diffusion and contact fabrication. The conductive ceramic substrate is fabricated from selected low-cost materials. The metallurgical barrier prevents the substrate impurities from entering and contaminating the active thin silicon layer. The randomly textured andhighly reflecting metallurgical barrier improves light trapping. A suitable p- type doped 30 - 100micro-cm active layer is deposited from a liquid solution. Phosphorus and aluminium impurity gathering are used for bulk quality improvement. Cells with large areas of 240, 300 and 700 cm2 are developed. A cell with an area of 675 cm2 has demonstrated the record efficiency of 11.6 -17.7%. The waste products present in the lunar surface are silicon, iron, TiO2, etc. These products can be used as raw materials for solar cell fabrication. A special compound called anorthite is used for extracting the above said components. Carbothermal reduction of anorthite,
Carbon compounds can also be used to extract Oxygen, Fe, and TiO2 from Lunar Ilemenite. The iron is used for interconnect and TiO2 for anti reflect.
Microwave
For direct microwave wireless power transmission to the surface of the earth, a limited range of transmission frequencies is suitable. Frequencies above 6 GHz are subject to atmospheric attenuation and absorption, while frequencies below 2 GHz require excessively large apertures for transmission and reception. Efficient transmission requires the beam have a Gaussian power density. Transmission efficiency çb for Gaussian beams is related to the aperture sizes of the transmitting and receiving antennas: çb ~ 1- exp (-ô2) and ô = ðDtDr/ (4ëR) Where Dt is the transmitting array diameter, Dr is the receiving array diameter, çb .is the wavelength of transmission and R is the range of transmission. Frequencies other than 2.45 GHz, particularly 5.8 GHz and 35 GHz are being given greater attention as candidates for microwave wireless power transmission in studies and experiments. The mass and size of components and systems for the higher frequencies are attractive. However, the component efficiencies are less than for 2.45 GHz, and atmospheric attenuation, particularly with rain, is greater.
Cost Forecasting
To achieve low unit cost of energy, the lunar portions of the LSP System are made primarily of lunar derived components. Factories, fixed and mobile, are transported from the Earth to the Moon. High output greatly reduces the impact of high transportation costs from the Earth to the Moon. On the Moon the factories produce 100s to 1,000s of times their own mass in LSP components. Construction and operation of the rectennas on Earth constitutes greater than 90% of the engineering costs. Any handful of lunar dust and rocks contains at least 20% silicon, 40% oxygen, and 10% metals (iron, aluminum, etc.). Lunar dust can be used directly as thermal, electrical, and radiation shields, converted into glass, fiberglass, and ceramics, and processed chemically into its elements. Solar cells, electric wiring, some micro-circuitry components, and the reflector screens can be made out of lunar materials. Soil handling and glass production are the primary industrial operations. Selected micro circuitry can be supplied from Earth. Use of the Moon as a source of construction materials and as the platform on which to gather solar energy eliminates the need to build extremely large platforms in space. LSP components can be manufactured directly from the lunar materials and then immediately placed on site. This eliminates most of the packaging, transport, and reassembly of components delivered from Earth or the Moon to deep space. There is no need for a large manufacturing facility in deep space. The LSP System is the only likely means to provide 20 TWe of affordable electric power to Earth by 2050. According to criswell in the year 1996 lunar solar power reference design for 20,000GWe Its also noted that the total mass investment for electricity from lunar solar energy is less than for Terrestrial solar energy systems.
Terrestrial Thermal power system - 310,000tones/GWe.
Terrestrial photo voltaic -430,000tones/GWe.
Lunar solar power - 52,000 tones / GWe.
Merits of LSP
In technical and other aspects there are two reasons for which we prefer LSP are:Unlike earth, the, moon is the ideal environment for large area solar converters.
The solar flux to the lunar surface is predictable and dependable.
>> There is no air or water to degrade large area thin film devices.
>> Solar collectors can be made that are unaffected by decades of exposure to solar cosmic rays and the solar wind.
>> Sensitive circuitry and wiring can be buried under a few- tens of centimeters of lunar soil, and completely protected against solar radiations
temperature extremes. Secondly, virtually all the LSP components can be made from local lunar materials.
>> The high cost of transportation to and from the moon is cancelled out by sending machines and small factors to the moon that produce hundreds to several thousand times there own mass in components and supplies.
>> Lunar materials will be used to reduce the cost of transportation between the earth and the moon and provide supplies.
Additional Features of LSP
The design and demonstration of robots to assemble the LSP components and construct the power plots can be done in parallel. The crystalline silicon solar cells can be used in the design of robots, which will further decrease the installation cost.
Economical Advantages of LSP and Crystalline Silicon Solar Cell
>> Crystalline silicon solar cells almost completely dominate world - wide solar cell production.
>> Excellent stability and reliability plus continuous development in cell structure and processing make it very likely that
crystalline silicon cells will remain in this position for the next ten years.
>> Laboratory solar cells, processed by means of sophisticated micro - electronic techniques using high quality Fe-Si substrate have approached energy conversionefficienciesof24%
1) Solar converter.
2). Microwave generator.
3). Microwave reflector.
4). Mobile factory.
5). Assembly units.
6). Habitat / Manufacturing units.
Conclusion
A global stand -alone system for renewable power would cost thousand of trillions of dollars to build and maintain. Energy costs could consume most of the world's wealth. We need a power system that is independent of earth's biosphere and provides an abundant energy at low cost. To do this man -kind must collect dependable solar power in space and reliably send it to receivers on earth. The MOON is the KEY.
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