Gear Ratio Problems

Our robot weights 11.5 pounds, and the motors are shutting down continuously. Does anyone have any suggestions for our gear ratio on the drive. As of right now we are using 6 motors on the drive, and we have a complex gear system with the ratio being 1:3. Please Help. We were thinking of increasing the torque.

make it 1: 1.6
1:3 is too fast
thats why your motors are overheating and shutting down

What about 1:2? Is that still fast, and will you encounter any problems with overheating/ shutdown?

Agreed. With a 6 motor drive and that gear ratio, you should not experience any problems. Also, if built correctly, that will even provide you enough torque to push other robots.

Agreed, we are 11lbs 110z. and 1:1.6 and we don’t stall or get pushed around. Also I think if we were almost twice as fast such as your ratio we would find it hard to control the robot.

What wheels are you using?
What type of motors are you using? (393’s, 269’s, or 3-wires)
If you’re using 393’s, are they set to speed or torque?
In what ports are they plugged?
Are you using a power expander?
Could you post a picture of your gearing?

6 motors on a drive is a lot… I’ve never tried a 1:3 ratio before, but something in me is saying that six motors might be able to handle that ratio with a robot that lightweight. (Again–I’m not in my realm of experience here, so I’d trust people like murdomeek more than myself.)

(I ask because freshman-physics torque calculations say this should be fine… I’m trying to find out if this is a breakdown of theory vs the real world. :wink: )

//Andrew

1:2 is safer. You’ll be fine with that. We have a robot running on that now with 4 motors without a problem.

How much does your robot weigh?

No idea. I don’t really weigh things that often. The first one was probably 10-12 lbs. It had two batteries, 10 motors, a 4-bar arm and Mecanum wheels.

The one we’re using now is maybe 8-10. At most. It’s incredibly light.