[chrisb]

For a robotic BLDC motor velocity control application, I moved to using a linear ADRC (Active Disturbance Rejection Control) [0] controller. It is not much more complex to implement that a PID, but at least in my context it handles changing real-world environmental conditions with a correctness which I could not achieve with a PID however much I tried to tune it.

Still uses a PID for BLDC motor coil current control, as this control loop is much more predictable.

Currently using the proportional part only from a PID for position control, but this may change in the future.

[0] https://en.wikipedia.org/wiki/Active_disturbance_rejection_c... (although this isn't a very useful reference if you want the implementation maths!)

[qsera]

I once tried to make a RC toy car so that it has proportional speed controls. I used some hall effect sensors to measure the speed at which the wheels are rotating and used it to compute the PWM signal that should be fed to the motor.

But the interference from the PWM signal appeared to mess with the speed sensor readouts that I couldn't make it work.

Can what you describe be used to solve it? If you would be kind enough to describe it, that would be great.

[chrisb]

I use an MT6701 magnetic rotary sensor mounted on the motor shaft, running in AB[Z] mode. This is used to measure the angle of the motor, and generate the correct PWM signals for the three motor coils. My inner current-control loop runs at 15kHz, using a PI controller.