Consider the PID controller of Example 12.3 for c = 8. (a) Suppose that the PID controller

Consider the PID controller of Example 12.3 for τc = 8.
(a) Suppose that the PID controller is implemented as the series form in Table 12.2, rather than as the parallel form that was employed in Figure. Are the simulated closed-loop responses significantly different from the ones in Figure?
(b) Suppose that τD is varied whereas Kc and τ1 are kept constant at the design values. For what values of τD is the dosed-loop system stable? Does the closed-loop system become more or less oscillatory as τD increases?