ME 422 - Introduction to Mechanical Controls

Homework 20

1.  Determine the transfer function for the system whose Bode plot is shown below. Determine T, z, w_n, M_R, w_R etc.—i.e. whatever is appropriate for the system.

2.  A system has the open loop transfer function GH = 2/[s(0.1s+1)²]. Use Matlab to plot the Bode diagram for this system. On this diagram, show the gain and phase margins. Make and label the gain crossover frequency (w_gc) and the phase crossover frequency (w_pc). Replace the steady state gain of 2 with K, an adjustable gain. What is the range of K for stability? Use the Bode plot to determine this approximately. Use the Routh criterion to confirm it analytically.