PI or PID Control of a voice coil motor


Thread Starter

Ivan Blackford


I'm working right now on a control system that moves an aperture from 0 --> 30 degrees based on feedback from an optical angle sensor. The actuator that I'm planning to use is a voice coil motor, since it has to move the aperture quickly, from rest to fully on in under 15ms.

What I need to know is what information about the voice coil would I need to know in order to design the control system? How can I setup a transfer function for a voice coil motor? I have researched motors from BEI Magnetics, and they list on their datasheet a mechanical time constant. How does this mechanical time constant compare to that spec'd for a DC motor?

Any information you can provide would be appreciated.

Thank-you for your time,
Ivan Blackford

Davis Gentry

I can't answer the question about the transfer
function, but can say that I have controlled voice
coil motors with direct PWM output from our controllers. In one application a few years ago we achieved an 80 kHz position loop for three VC motors with move and settle times in the low ms range. 15 ms just for the accel phase seems very achievable assuming enough current capacity for the load.

Davis Gentry
Hi Ivan!

Could you find the transfer function?

About PD or PID Control, I tried PD control,
and can send you MatlabSimulink file. But usually you will need some additional springs.

But the best solution is Stata feedback Control.


Ivan Blackford

Hi Max!

Sorry about the long delay, I didn't realize that there was an update to my post since I don't check here that often. I would love any Simulink files that you can provide to give me some insight into controlling a voice coil motor.

Feel free to email me at iblackford @ gmail. com

Thank-you for your time,

hi sir

i am engineering student working on voice to control motors for a research project. kindly guide me the right approach to start it, i mean softwares to be needed, tutorial (if available with you).

my mail is [email protected]
i will be very thankful to you .

warm regards
deepender singla