Inexpensive motion control using DC motors

摘要

Disclosed herein is a motion monitoring system for monitoring movement of a brush-type DC motor. The system includes an electrical comparator having first and second differential inputs. A current detector is connected to provide a drive current signal to the first differential input of the comparator. A low-pass filter is connected to provide an averaged drive current signal to the second differential input of the comparator. When a drive current is applied to the motor, the comparator produces a stream of binary logic-level pulses corresponding to motor movement. The pulses can be used to determine motor position and velocity.