Current controlling a dc motor

Robotics and electronics discussion Electronics
1

Hi Everyone,

I was curious whether anyone had any good ideas for getting current (and therefore torque) control on a dc motor using ICs, and have it voltage controlled. I wish there was a small integrated package/breakout board, but I can’t seem to find any.

The obvious thing that I guess I could do is use a microprocessor and dedicate it to do a high-speed closed-loop controller, using the current sense line from one of the motor drivers pololu offers. But i’m not sure how practical this is (I’m not sure really what the current sense on those drivers do, what their response time is, etc).

I generally look at driving motors within the 0.5-1.5A range. Any suggestions?

2

Hello.

Using a current sensor to get current feedback sounds reasonable, and the current through a brushed DC motor should be linearly related to the torque. You could use the current sensor built into one of our motor drivers or one of our separate current sensors in line with the motor power supply. More information on each current sensor is available in its or its associated motor driver’s datasheet, which can be found under the “Resources” tab on their product pages.

- Grant