I am wondering how can I limit the current under a certain value (thus I can set the value of the maximum torque), let’s say 3A using the single MC33926 driver board and an Arduino? I learnt that I can set the PWM duty cycle from D2 or D1 to control the speed and read the current, but I am not sure about how the torque is controlled.
Pololu jrk motor is also using MC33926 and the current can be limited to a certain value set by the user. I don’t know if I can do the same thing with a MC33926 driver and an Arduino.
The torque provided by the motor is proportional to the motor current. On our jrk 21v3, we use the analog feedback from the MC33926 to limit the power to the motor when the current exceeds the limit set by the configuration software. It is probably possible to do a similar type of thing by using the FB pin on our MC33926 driver board and the analog input pins on an Arduino.
I am wondering if you could explain further on how do you limit the power at this step? I guess it would be something like a PID current control. Should I just give a lower duty cycle for the PWM on D2 port, or I need to use additional circuit to limit the power?
A PID algorithm that changes the PWM duty cycle to reach a motor current target sounds like it could work, and you probably do not need additional circuitry to accomplish that.