Have you ever wondered if you could control a stepper motor’s speed and direction using an RC servo controller (for example from the stick of a RC airplane transmitter)? Wonder no longer – using a Fubarino Mini and a Big Easy Driver stepper motor controller, Brian Schmalz was able to write a simple sketch to enable precise control of a stepper motor from an RC servo input signal.
This sketch uses a 32-bit hardware timer and output-compare module on the PIC32 so that very accurate step speeds are generated. Step speeds from 1 step per second to over 12,000,000 steps per second can be configured using #define values in the sketch. There is also a configurable dead zone in the stick’s center position.
One advantage of this type of control system over a simple DC motor controller is that the speed of the stepper is not dependent on the load (to a point), so you can very accurately control the speed of whatever you are moving even if the load torque changes over time.
Check out the simple video of this sketch in action:
For complete instructions on how to duplicate this setup, see the complete description here on Brian’s site: RC Servo to Stepper Sketch