Control DC Motor Speed with external signal

[macmmt]

Control DC Motor Speed

Hi,

I have to control the speed of a motor.

After I get the control signal I need to send it to an actuator to change the speed of the DC Motor.

I was thinking to use a circuit (attached image) with a IC 555 and a MOSFET. So by changing the duty cycle of the PWM I will change the speed of the Motor.

The problem is that the circuit is using a potentiometer to do this job, and I want to use the control signal to change the speed. Please, do you have any idea how I can do this??? Maybe the pin 5 of the 555?? Please help me to find a solution, or what kind of actuator I can use to change the speed of the motor?

Thanks for your help,

Macmmt

 

[elrayes]

Control DC Motor Speed

first solution you can replace the potentiometer with digital potentiometer which you can control its value through a pulse signal.
another solution:
do you know how to use microcontrollers?
i think will be better solution, PIC18F452 and PI16F877 both have built in PWM module you can easily control.
good luck