The worktable of a numerical control machine tool is driven by a closed-loop positioning system which consists of a servomotor, leadscrew, and optical encoder. The leadscrew has 4 threads/in and is coupled directly to the motor shaft (gear ratio = 1:1). The optical encoder generates 200 pulses per motor revolution. The table has been programmed to move a distance of 7.5 in at a feed rate = 20.0 in/ min.
(a) How many pulses are received by the control system to verify that the table has moved the programmed distance? What are
(b) the pulse rate and
(c) motor speed that correspond to the specified feed rate?