Top Down Assembly

Firstly, you need AAX module to be able to use Layout. As for tutorials, please read through the HELP files Thoroughly to understand the concept of Layout and Skeleton models. There are a few videos available under "Tips and Tricks" on PTC's site. There is also a "Suggested Technique" available at www.ptc.com on Skeleton modeling. Having understood this, you should be on the right course. Any Classroom training would definitely help.

Arun,

I came across a discussion and a video about Top Down Design

Enterprise Top Down Design a reality with Windchill 10.0

Windchill 10.0 Enterprise Top Down Design

Stephen Shaw may be abke to help out more.

-Dan

Hi Arun,

I am not a fan of Layout. This is based on using it back in R16 (1996) for one major project. It is powerful but was not an easy to use tool. Maybe usability has changed in later releases but we felt burnt and have not been back there.

After that we used Datum features at the assembly level and some ugly copying between models. As soon as we found out about Skeleton Part functionality we started using it and have continued with it from there. Some companies used the Master Model method which was the precursor to Skeletons however we never used that method.

In our high level Skeleton we have all the Datum planes,axes, points and coordinate systems that we use for interactions between parts. As well as this we have surface modeling for product shape and this is often quite complex. We make numerous Publish Geom features that have groups of these Datum or surface features for use in models or sub-assemblies. We also has assembly level Parameters and Relations in the Skeleton.

Even though we are quite thorough in trying to figure what part interactions and references we will need we find that we usually have to add more features and Pubgeoms to the Skeleton as we start development and get into the "nitty gritty". With Skeletons we find this change on the fly to be really robust.

We have two methods of assembling parts or sub-assemblies to our main assembly. We either assemble in the default location or we assemble to skeleton features (e.g. a screw to an axis and a plane). By doing this no matter what changes are made to any part the assembly still assembles.

• If we assemble at the default location this is because we want to take Copy Geometry from Skeleton PubGeoms and build the part using those (and only those) references.
• If the part is a stand alone or OEM part (e.g. screws) then it is modelled separately and assembled to the Skeleton.

We can have Skeletons in sub assemblies but only have those for reference information that is specific to that sub assembly. We used to have Publish/Copy information from the higher level to the lower level but found this was an unnecessary overhead. If we have parts in a subassembly we do use CopyGeoms from the highest level Skeleton directly.

Works for us over numerous projects and is pretty bullet-proof. The main worry is two people trying to work on the Skeleton at once (we do not have PDM) however with a relatively small team we are careful about this.

As far as I can see this approach will work well for the sort of assembly you propose.

Hope this helps.

Regards,

Brent

A basic tutorial look this video http://modelacion3d.blogspot.com/2010/10/skeleton-model-proengineer-50-part-1.html

Arun,

I reccommend that you read and study Brent's response; there's lots of good detail there. Thanks for your time, Brent! I strongly agree that Skeleton Models are powerful and robust as well as being easy to understand. Combined with parameters, relations, Publish Geometry, etc., they can handle most situations very well. There is a directness, too, because you are dealing with 3-D geometry in the right location from the beginning, without needing to setup a layer of abstraction above it in Layout.

That said, if you can put in the time to really learn Layout mode, there is a lot of nifty power there. You need to evaluate your own needs, but the Skeleton approach may be just what you need.

David