Hello everybody,
I am using an l293d h bridge to drive a dc motor. This works happily and I can control the speed using pwm from a microcontroller.
I also want to determine the speed of the motor without an encoder (due to space restrictions). I can do this using the method described at http://www.romanblack.com/encoder.htm
This method doesn't work with pwm because the output to the motor isn't constant but an amplified PWM.
What I think could work is to make an amplifier that takes a pwm input and provides enough power to run the l293d motor supply. I haven't had any luck doing this. I have tried transistors and op-amps but neither provides enough current.
I appreciate any suggestions.
I am using an l293d h bridge to drive a dc motor. This works happily and I can control the speed using pwm from a microcontroller.
I also want to determine the speed of the motor without an encoder (due to space restrictions). I can do this using the method described at http://www.romanblack.com/encoder.htm
This method doesn't work with pwm because the output to the motor isn't constant but an amplified PWM.
What I think could work is to make an amplifier that takes a pwm input and provides enough power to run the l293d motor supply. I haven't had any luck doing this. I have tried transistors and op-amps but neither provides enough current.
I appreciate any suggestions.