Monday, March 10, 2014

AMHS Robotics MkII Drivetrain

I designed this chassis while participating in the FIRST Robotics Competition.  Key considerations were standardization of parts and manufacturing simplicity.  3D CAD, CAM, and 2D drawings were key to making the design come alive.

The chassis served as a platform to move around a field the size of a basketball court.  Coupled with an extending arm designed by the rest of my team, our machine joined up with other schools on the field to stack tetrahedral game pieces on to scoring racks.

Machined components assembled with some of the drive electronics
3D model of one of the wheel assemblies

Shop drawing for one of the aluminum rims
Two rims fit back-to-back to form a wider wheel, and were assembled with sprockets and spacers to interface with the electric drive system.  The front wheels were raised slightly off the ground to reduce the effective turning radius (but still present to support the machine if it tipped forward).

3D rendering of a complete drive side

Test run of MkII with the upper arm mounted to the chassis
The machine performed well for its first trial.  It was stable, as expected, but the exceptionally low profile made maneuvering around obstacles somewhat awkward.  Future iterations would raise the ground clearance.