Motors in reverse mode

Support Motor controllers/drivers and motors
1

Hey,

I am doing a mechanism that will require some motors to go in the reverse direction.
You have four different pololu motors that may interest me:

  • 2214: Micro Metal Gearmotor HP with Extended Motor Shaft 100:1
  • 2373: same but 1000:1
  • 2276: Metal Gearmotor 25Dx54L mm HP 6V with 48 CPR Encoder 100:1
  • 1446: Metal Gearmotor 37Dx52L mm with 64 CPR Encoder 100:1

I would like to know if they can go in reverse mode. Two motors will work on the same axis with different direction, will it damage the one working in the reverse direction? If no current is applied, can we turn them manually, then, what will be the torque ?

Thanks,

Matthieu

2

Hello, Matthieu.

The gearmotors you mentioned are all brushed DC motors, so switching the polarity of the voltage applied to the motors terminals will cause the motor to spin in the opposite direction. While it is possible to turn the shafts on the gearmotors manually, we do not recommend doing so as it could damage the gearbox.

It is not clear to me how you are intending to use the motors from your description; could you post a diagram?

-Brandon

3

Okay, I have a diagram:

testBench@.png821×433 19 KB

The purpose of this test bench is to make an antibacklash system.
But then, I need two motors with one in reverse mode. The second motor (M2) should do reverse mode while the input current ask him to go in the straight direction.

Is it understandable?

My question was, do you think it is possible to do this?

Thanks!

Matthieu

4

This makes it sound like you might be intending to have one motor powered in a way to make it spin against the motion of your system to keep pressure on the gear (e.g. power it so it would spin clockwise, but have your system forcing it to turn counterclockwise). If that is the case, this would almost certainly damage the gearmotors, and I would highly encourage you to come up with a different way to prevent or correct for backlash.

If you are planning on just having one motor powered at a time, with one motor backdriving the other one, I do not think this would be a good solution for handling backlash, and as mentioned in my previous post, we do not recommend backdriving the gearmotors as it could damage the gearbox.

-Brandon

5

High precision orientation mechanisms often use a toothed belt, which essentially eliminates backlash.
en.wikipedia.org/wiki/Toothed_belt

6

Ok, thanks for the advice.