Servo-mechanism with position comparison circuit - performs coarse or fine control using sensors on two relatively moving members

摘要

For the servo mechanism the relative positions of two members are compared to obtain difference or error signal. Movements are detected to effect required coarse or fine control. A mechanical assembly (1) is coupled to position sensor (2) and a second mechanical assembly (3) is coupled to a similar position sensor (4). The sensor signals are passed to a comparator (5) whose output is amplified (6) to drive a motor (7) to act on second mechanical assembly (3) to reduce the error signal when compared with the output of the first position sensor (2).