A unit feedback digital control system at a sampling inteTval of 0.058ec. If the plant transfer function is given by z+0.8 G(z) = (z- 1)(z- 0.8) ·

Design the controlleT D(s) using root locus methods so that the closed-loop system satisfies the following time domain specification:

settling time :::; 0.4sec damping ratio 2: 0. 7 steady state ermr =zero (step input).

Problem