motor feedback

[engkeat]

i m using an incremental encoder to feedback the speed of a dc motor. i am concern about the frequency of the pulse generate from encoder as i need a find a set point (desired frequency/speed) , the motor is used to lift up a load at a constant speed. during the lifting, torque required is changing, meaning voltage required is changing as well..so i need to control the voltage supplied to motor through the feedback pulses, i m using PIC as the controller. my question is that... can PIC detect the continuous changing pulse from the incremental encoder??? o do i need any converter?

 

[3v0]

Yes. Use the PIC to count the time between pulses on either channel A or B. Constant speed will result in equal lenght pulses. If the pulses get too long increase the voltage. Too short decrease the voltage.

You will want to read about PID control. The web has several tutorials on the subject.

3v0