Old spec 3.6 example, closed-loop control of vehicle speedTutorialOld spec ENGR202Third6 min

ENGR202 (old spec) Control 3.6 Block Diagram Analysis, closed-loop control of vehicle speed (slides 5-7 and 16-19)

The speed XX of a vehicle is controlled by a proportional controller U=Kp(D−X)U = K_p(D - X), where DD is the desired speed and UU the engine force. The vehicle model is X=0.85s+1UX = \dfrac{0.8}{5s + 1}U (unity negative feedback of the speed).

Formulas you may need
  • Unity negative feedback: X=C(s)G(s)1+C(s)G(s)DX = \dfrac{C(s)G(s)}{1 + C(s)G(s)}D (learn this)
  1. (a)
    Use the rules of block diagram analysis to find the Closed-Loop Transfer Function X/DX/D.
  2. (b)
    For Kp=5K_p = 5, find the closed-loop steady state gain and time constant.