Servo Control With Microprocessor
Original Publication Date: 1989-Apr-01
Included in the Prior Art Database: 2005-Jan-27
Improved accuracy of velocity and position control in a motor-driven servo loop is obtained by using a microprocessor to regulate acceleration and position. In Fig. 1, DC motor 1 is driven by a signal from velocity control circuit 2 powered at 3. The motor drives tachometer 4 whose velocity signal is continuously compared at velocity control circuit 2 with a position error value from digital position control unit 5 changed by digital-to-analog converter (DAC) 6 to an analog value. Motor 1 also drives position emitter 7 that produces an output pulse for each predetermined unit of displacement traveled, such as 0.001 revolution. The difference between a command value of displacement and actual value is determined at position control unit 5 and monitored by microprocessor 8.