P10.8 is an interesting problem in attaining sufficient ac A numerical path-controlled machine turret lathe -

curacy [2, 23]. A block diagram of a turret lathe con

trol system is shown in Figure P10.8. The gear ratio is

n J = = 0.2, 10−3, and b = × 2.0 10−2. It is necessary to attain an accuracy of 5 1 × 0 −4 in., and therefore a steady-state position accuracy of 2.5% is specified for a ramp input. Design a cascade compensator to be inserted before the silicon-controlled rectifiers in order to provide a response to a step command with a percent overshoot of P O. . ≤ 5%. A suitable damp

ing ratio for this system is ζ = 0.7. The gain of the silicon-controlled rectifiers is KR = 5. Design a suit

able phase-lag compensator.