Feedback in microcontroller

[ymmen]

Hello,
I have to control speed of a dc motor using arduino. Using tachometer i detect speed of the motor. However how will i decide the value for pwm.
Iam using arduino. What should i write inside function analogwrite();
Thank you

 

[Easyrider83]

You have to use PID alghorithm for example.
https://copy.com/cBNoEbqhJbiSG3Zk

 

[ymmen]

Very true. However my question is little different. The final output of my microcontroller will be " pwm( error + fixed value). How do I calculate that fixed value?

 

[Easyrider83]

It will be calculated by PID. You just have to set desired speed.