FEA Convergence - Ensuring accurate simulation results in Inventor



One of the foreign concepts to many people new to FEA is the idea of "Convergence". Convergence is an analytical method that many analysts use to determine the quality of their FEA results. Since FEA uses small elements to solve complex problems, a larger number of smaller elements can sometimes yield more accurate results. But how small is small enough when it comes to element sizes? This is where convergence comes into play. Convergence in Inventor Simulation is actually a series of settings that can be used to automatically make mesh elements smaller, and help determine if results are accurate.


The basic concept is that the mesh will automatically be made of smaller elements and solved until the results of the refined mesh fall within a percentage of the previous mesh. In other words: The smaller mesh is no longer significantly changing the results, and it making it smaller would yield diminishing returns.


In the image below, convergence settings were used to determine the validity of the FEA results. Before using convergence, the stress in the model was calculated to be 5.85 ksi. After turning on convergence (which refines the mesh and makes it smaller), the stress was calculated to be 6.205ksi with only .448% defiation from the previous iteration. This shows us that we can trust our FEA setup and gives us more confidence in our solution.




Contributed by Ben of the Tata Technologies CAD Geeks

Creating Symbols with Design Review

Custom symbols can be made from 2D content in DWF files. You can create a separate symbol from each object, or block, if the block template information was included in the DWF file when it was published by a design application, such as AutoCAD. (For nested objects, only the top-level object is imported.) You can also create a separate symbol from each 2D sheet in the DWF file, regardless of how many objects are on a sheet.
As a type of markup, symbols can be used and reused on any 2D sheet. The benefit of symbols is the easy access to and consistent reuse of common symbols.

In addition to DWF files with drawings and text, you can also use DWF files with images or snapshots as symbols. Image types include:
- Sheets created by the Snapshot tool.
- JPEG (.jpg, .jpeg, .jpe, .jfif)
- PNG (.png)
- TIFF (.tif, .tiff)

Video link:
http://www.screencast.com/t/MTYyNGViN2Et

Created by one of the Cad Geeks

Design portability with Autodesk Vault




One of the benefits of Vault that can improve Inventor's performance in large assemblies also makes it easier to take your work with you if you leave the office. What am I talking about...

A local working folder or "Workspace" of course. Let me fill you in on the background first: Autodesk Vault is a Client / Server application with "Checked In" data residing on the Vault Server. But data that is "Checked Out" actually resides on your local workstation's hard drive. Vault is always automatically monitoring the relationship between the server and local data and displays its status when logged into Vault.


Due to this data residing on your local hard drive, you can log out of Vault and still work on any designs that have been checked out (and thereby cached in the local working folder). Tata Technologies typically even Vaults files such as Templates and Style library data so you can work without interruption when disconnected from the corporate network.
As mentioned earlier, due to the data being local when you are working in a Vault environment, large assemblies in Inventor can be more responsive to the common tasks of opening and saving regularly as well.
Contributed by Ben of the Tata Technologies CAD Geeks

Electrical - Displaying Terminal Strip Information

When working with terminal strips AutoCAD Electrical offers a few different ways to display the information on our drawings. Of course we have the ability to display the terminal strip graphically and also with two types of charts. The video created for this post will show how to work within the terminal strip editor to create and place the charts onto our drawings.


Video link:

Created by one of the Cad Geeks

HTC Sweden Video

Great example of how companies can take advantage of Autodesk solutions for digital prototyping.