Question

2. An active suspension system for AMTRAK trains uses a pneumatic actuator in parallel with the passive suspension system. The force of the actuator subtracts from the force applied by the ground, as represented by displacement ⅞φ. Acceleration is sensed by an accelerometer, and signals proportional to acceleration and velocity are fed back to the force actuator (50pt). You may use MATLAB for this problem Obtain the transfer function s Im(S)/Yg(S) relating acceleration to ground displacement (15pt) Assuming that M=1, D=K=C,-2, sketch a root locus for varied C。 (20pt) Find the value of Ca that would yield a damping ratio of 0.69 for the closed- loop poles (15pt). a. b. c. ym(t) ymCt Accelerometer ym(t) Ca Actuator force