Duckietown Duckiebot Motor Mount

thingiverse

This is a motor mount for robots described in: http://duckietown.org The main goal of this part is to attach plastic motors to the DAGU chassis. The original method involves using four red plastic pieces that hang from the top and are used with screws to secure the motors. However, we noticed several problems with this approach: a. After calibration and regular use, the robot's calibrations change because the motor mount shifts. b. When using screws to attach the motors from the side, it squeezes the gearbox, causing inconsistent power requirements for the motor to move. This results in a lot of current being needed just to get the motor started, followed by less current as it continues moving. If the screws are tightened too much, this can cause the robot to make a S pattern due to algorithmic corrections. c. The red plastic parts protrude from the chassis, obstructing battery mounting. We designed this part to address these issues. Although it's still a work in progress, we have not yet successfully resolved issue a. To assemble the motor mount, start by popping five plastic M3 nuts into the bottom of the part that will attach to the chassis. Use four M3 metal nuts for the motor mount holes; note that they are slightly smaller. Once you've added these nuts, glue them in place using a few drops of ABS cement. The photos with white parts show how to properly position the screws. Next, mount the motor mount to the chassis, and it will guide the motors smoothly. Attach the two small side pieces and screw them in – just make sure they don't touch too hard on the motors. The last three photos demonstrate how this piece is mounted. This part serves as a kind of axle, restricting motor movement from the mount by providing a wall for the motor to align with. It's still a work in progress because the motors can still move slightly. If you look at the front part, you'll see an opening with a hole aligned with the front holes of the yellow motor box. Our plan is to use a metal rod to pass through and hold the front holes of the motors securely. We may even print another piece to snap between and hold the motors firmly in place. To use the battery mount piece, you need to print this one first.