Pot Gyro

[archiver]

Posted by Tim Gates at 2/14/2001 9:04 AM EST


Engineer on team #288, RoboDawgs, from Grandville High School and X-Rite/Delphi.


In Reply to: Pot Gyro
Posted by Jason294 on 2/13/2001 11:36 AM EST:



Jason294;

We designed and built an inclinometer as a backup for the gyro-chip as a result of damaging the first one banging up and over the ramp. Our current gyro-chip will be shock mounted to prevent a repeat. The short shaft 100K pot recieved in your freebies requires
6 oz./in. to overcome friction between the wiper arm and resistive compound in the pot. I don't know if that is static or dynamic coefficient of friction. A ten to one gear ratio will match the 280 degree sweep of the pot with the +/- 14 degrees of the ramp, but will bottom out so to speak. We used an eight to one (120/15 tooth) gear ratio which results in three in./lbs. to overcome the base friction. In retrospect, the high gear ratio gave us better resolution but resulted in needing more than three in./lbs. to get acceptable response. We only need to sense when the ramp starts rotation and are not concerned with oscillation when the mass on the end of the pendelum relaxes to a balance. Because the RoboDawg travels through the barrier, height is a consideration and the shorter the robot the more precious real estate becomes in the chassis. Don't hesitate to try it, every learning experience is of great value.

Tim Gates
Controls Engineer
Team #288 RoboDawgs