Motor direction control circuit at certain voltage level

Thread Starter


Joined May 21, 2019
I am designing a self balancing robot without arduino I have two motor for wheels attached to motor driver unit. I am supposed to use IR sensor that outputs certain voltage for certain distance. Now I need help in designing a circuit to control direction of wheels at certain output from IR sensor.
All I need is
for 1st IR
if voltage =x
rotate motor in +ve direction
for 2nd IR(opposite to 1st)
if voltage =x
rotate motor in -ve direction

any help or suggestion will be greatly appreciated.


Joined Mar 14, 2008
Use an H-bridge to control the motor.
Use a comparator at each IR output = to detect the desired IR sensor signal, and use the comparator output signals to control which of the two transistors in the bridge on are on.

Is this strictly an ON/OFF type control for the motor?
If, so, I doubt that will work to create a self-balancing robot. :(


Joined Jul 18, 2013
Sounds similar to the self balancing scooter.
The balancing is typically done with servo's using PID etc, there is a close example in the Picmicro Pendulum project.
But micro is used.