Submersibles with clear plastic hulls have the potential to revolutionize underwater leisure. One small submersible vehicle has a depth-control system as illustrated in Figure E4.9.
(a) Determine the closed-loop transfer function T(s) = Y(s)/R(s).
(b) Determine the sensitivity STK1 and STK.
(c) Determine the steady-state error due to a disturbance Td(s) = 1/s.
(d) Calculate the response y(t) for a step input R(s) = 1/s when K = K2 = l and l Figure E4.9
Depth control system.

Disturbance TMs) Ms) Actual depth R(s) depth Sensor