How control the TORQUE of a motor?

Hi guys!!

I’m building a very simple manipulator with 1 stick and 1 motor, but I have a problem with the motor: I can provide a PWM signal and I want to obtain a particular torque on that stick, but I have no idea how to do! I don’t know anything about motors…I learnt to command a servo motor, but that works only setting the position …not the torque! can you suggest me the simplest solution?

Actually, This is a very little piece of a bigger project, so I don’t want to spend too much time on it, that’s why I need the simplest solution… if you know any kind of motor like a servo which takes a PWM signal and sets the torque (instead of the position), would be the best thing for me…but even a electric circuit for the driver of the motor, is ok! (I think can easly build it) thanks very much!!

The torque generated by a brushed DC motor depends on the current through it, which in turn depends on the voltage of the power supply, the resistance of the motor windings, the rate at which the motor shaft is turning and whether you are using pulse width modulation (PWM). So, you need to control several variables to “set” the torque.