Here is the robot we designed in the past month or two as practice, and also probably as a base design for this season. It’s CAD files (both Inventor 2012 and STEP) are available on google drive: https://drive.google.com/folderview?id=0B0soKk9hjXfLejVfd1VTM2hQMEk
It’s main design goals were low weight/CG and repeatability, as we were disgusted with our very high CG and weight last year, and because we plan on building two robots this year which will have to be almost identical. Almost all of the chassis is waterjetted 1/16th inch 5052 aluminum, the bumpers are welded 3/16th 6061 aluminum, and the drivetrain has 1/4th inch aluminum plates. The drivetrain is a simple 2 speed supershifter, 4 CIM, 8 wheel drivetrain with #25 chain, the wheel axles are on moving plates instead of having tensioners for simplicity. The bumpers were designed for rigidity above all else and will be reversible so that we can put many bolts into the chassis as we want and only have to undo them once or twice per competition. The robot, with everything except battery, bumpers, and wires, weighs 48 pounds with a CG about 3 inches above the ground, the bumpers weigh around 15 pounds without fabric or pool noodle.
In the inventor formatted version, “FF14-C-18-AA Parameter File.ipt” contains many exported parameters that can change just about anything on the robot, for example, there are width and length parameters that change the robot’s width and length. This allows many changes to be made with almost no effort, however the controls board may get messed up by some of them. Also, in inventor, since everything was made using the sheetmetal template, you can click “Go To Flat Pattern” under the sheet metal tab to get the flat pattern which can be exported to dxf for a waterjet machine to use.
Each non-COTS part has a part number in the pdf log file, a render is included, and zipped STEP and inventor formats of the CAD are included. All of the files are also
Feel free to ask questions and/or give suggestions.