Meeting Log 3/12

By Trey and Leo

Task: Decreasing the Movement of Linear Slides During Expansions

The continuous expansion and contraction of the robot placed a lot of stress on the mounting gear attaching the slides directly to the chassis. With each expansion the slides stretch out, and under their own weight, they would flex downwards. During regionals, the slides were subjected to these forces all day, and by the end our sliding components, “carriages”, were pretty damaged. The internals were unevenly worn and the ball bearings just fell out on the field; If left unattended, the carriages would eventually detach from the slides and the robot would literally break in two.

To fix this, Trey came up with a double-carriage approach, aimed at reinforcing the mounts attached directly to the front of the robot. He machined an aluminum plate on the CNC, and then combined two different carriages to create a single sliding component. This effectively doubled the “strength” of the mounts by shifting the pivot point of the slides further in, and adding more resistance to the gravitational torque acting on the bar. Overall, the slides weren’t as steep and so carriages were much smoother during extensions.

Next Steps

We noticed that the slides did sag a little, however we need some compliance to allow for twisting caused by sharp crane movements and turns.We also noticed that the slide attached to the swerve module did flex so we might need to address that. Testing was limited however so we’d like to get some driver practice in and see how well the upgrades perform on the field.