pic: 2 Speed Transmission

[Joel J]

Originally Posted by Lil' Lavery

15 fps is probably too fast for FIRST purposes. Most teams and drivers agree you lose the ability to easily control your robot after about 11-12 fps. Additionally, you can easily outrun most other teams at around the same speed.
If you wanted to keep the 3:1 ratio, I'd aim 12 fps and 4 fps (with inefficiencies slowing it slightly from those values).

I agree that 15fps is too fast, if that's the final speed. But it looks like he's gearing the robot to move at 15fps, which means it'll probably end up in the 12-13fps range, which is good.

I think the ideal low gear is in the 5-6 fps range, and the ideal high gear is in the 11-12fps range, after inefficiencies, but those numbers (especially low gear) may not be very feasible, depending on the weight of the robot, and the tread being used (that is, how strong the robot needsto/will be able to push). I have always thought that robots moving in the 3-4fps range were too slow.

Basically, I agree with the OP's speeds.. I would even say to make the low gear a bit faster, but blah.. I understand the current draw issues that may arise as soon as some good tread gets put on the wheels.