CAD Info

Revision as of 13:19, 9 November 2006

CAD Models for Lego components can be found at: http://gicl.cs.drexel.edu/repository/data/repository/Lego/ There are many models in various subdirectories. STEP, VRML and I-DEAS formats should be available.

.sat, .stp, and .wrl files for lego parts are located in http://gicl.cs.drexel.edu/repository/data/repository/Lego/Drexel_GICL/

Here is a repository of named and categorized Lego parts in mostly .sat and .x_t (parasolid) formats.

Media:lego_cad_files.zip

Instructions for importing parasolid files into Adams:

Inside Adams, in a model and using an existing part, import a file of type parasolid (x_t), pick the parasolid file to import. Now that you have imported the part you will need to assign it a mass and center of gravity. Add a marker to the part at the geometric center of gravity of the part. Select the imported parasolid part, right click on it and select modify (on the part, not the solid), click on define mass by geometry and density, enter 1060, click on define mass by user imput, delete the entry under center of mass, double click on that entry and select the marker that you added to the center of gravity of the part.

Please add any clarifications or questions here.

Importing .stp files to Adams

Inside a particular model (mine is called legos),

go to File/Import set the file type to STEP (.stp) set File To Read to your .stp file (from the web repository, save the .stp file to your local machine) remove whatever is in the "relative to" textbox, double click there, click on your model name (.legos for me) in part name, double click, then click on ground under your model name (legos for me)

leave all other options as defaults, click OK

If you cannot see your part, click on View/Part Only.

This will import your part as a shell and attach it to the ground.

These directions are very hackish, feel free to improve them.

Additional Directions from going from STP file to Adams via Pro-E:

picked a lego file (24 tooth gear) 3648.stp right click on the link and save as 24tgear.stp in pro-e, open files, open file of type step, open 24tgear.stp, open as a part save a copy of the file: export as parasolid, had clicked on solids and shells in adams, import file of type parasolid

right click on the imported part, select part menu, part 3 for me, modify

under mass properties, geometry and density, enter 1060 (which is density of lego plastic (1020-1060 kg/m^3)), and then click apply create a construction marker geometry, put it at the center of the 24 tooth gear right click on the gear again, select part menu, part 3, modify, mass properties, user input, center of mass marker (delete what is there), double click in the area then select the marker (marker11 for me) that you added, also add this as the initial inertia reference

Some parts do not exist in .stp format, and some do not have informative labels.

Here is a start of a label map for the parts:

axles, numbers increase with increasing size, not a very exact scale

1 3704.stp

1.5 4519.stp

2 3705.stp

3 3706.stp

4 3707.stp

5 3708.stp

somewhere b/w 3 and 5 3737.stp

somewhere b/w 3 and 4 32073.stp

connectors

round to round 3673.stp

round to axle 3749.stp

round to tiny round 4274.stp

bricks with round crossholes

10x1x1 9 holes 2730.stp

1x2x1 1 hole 3700.stp

1x4x1 3 holes 3701.stp

1x6x1 5 holes 3894.stp

1x8x1 7 holes 3702.stp

1x12x1 11 holes 3895.stp

1x14x1 13 holes 32018.stp

1x16x1 15 holes 3703.stp

bricks

1x1x1 3005.stp

1x2x1 3004.stp

1x3x1 3622.stp

1x4x1 3010.stp

1x6x1 3009.stp

1x8x1 3008.stp

1x10x1 6111.stp

1x16x1 2465.stp

2x2x1 3003.stp

2x3x1 3002.stp

2x4x1 3001.stp

2x6x1 2456.stp

2x8x1 3007.stp

2x10x1 3006.stp

4x6x1 2356.stp

4x10x1 6212.stp

8x8x1 4201.stp

plates

4x10 3030.stp

4x4 3031.stp

4x6 3032.stp

4x8 3035.stp

gears

8t 3647.stp

24t 3648.stp

40t 3649.stp