pic: Team 1093 Nearing Completion

[Jay TenBrink]

Steven,

Thanks for posting your photo. I think this type of sharing is a healthy thing for teams and can benefit them as much or more than those that view only. I also think it is perfectly acceptable for teams to benchmark other robots, either from previous year’s designs or their postings.

We also have a similar device to power our elevator mechanism (I would refer to your application as an elevator device as well). Last year we had a window reg. motor and an aluminum gear. This year we have the van door motor with a 35 pitch aluminum sprocket. Our elevator arm is protected from overload with a slip clutch.

If your pinion sprocket is on the motor shaft, you need to support the end of the van door motor shaft with a bushing or bearing. Perhaps you could drill out a bronze flanged bushing to 11mm for this.

Since the van door motor can be back driven, we have installed a manual window regulator clutch between the motor and pinion sprocket. If we didn’t have this clutch, the arm would drop down with the weight of a tetra. A ratcheting device would also prevent this.

You can also solve this problem with software if you have a potentiometer on the elevator to provide feedback on the arm position. The controller would provide enough power to the motor to make it dwell. In time this will heat up the motor, but for a few seconds at a time it might be ok.

Jay