UNIVERSIDAD POPULAR DEL CESAR – CONTROL II, GUIDED COURSE
Homework #2
    For Everyone (5pts each):
       1. Three closed-loop transfer functions are given as follows:
           In each case, provide estimates of the rise time, settling time and percent overshoot to a unit-
           step input in r.
       2. The transfer function of a typical tape-drive system is given by:
                                               	
	
           Where time is measured in milliseconds. Using Routh’s stability criterium, determine the range
           of K for which this system is stable when the characteristic equation is 1+KG(s)=0
               UNIVERSIDAD POPULAR DEL CESAR – CONTROL II, GUIDED COURSE
    3. Consider the feedback control system in Figure below, where
       𝐺1(𝑠)	=	 s+1	and 𝐺2(𝑠)	=	    1	
                 s+2	              s+1		
           a. Using Matlab, determine the closed-loop transfer function
           b. Obtain the pole-zero map. Where are the closed-loop system poles and zeros?
           c. Are there any pole-zero cancellations? Why is it important to cancel common poles and
               zeros in the transfer function?
    4. The shoulder joint of a robotic arm uses a DC motor with armature control and a set of n gears
       on the output shaft. The model of the system is shown in Figure with a disturbance torque 𝑇d(𝑠)	
       which represents the effect of the load.
       UNIVERSIDAD POPULAR DEL CESAR – CONTROL II, GUIDED COURSE
    a. Determine the steady state error when the desired angle input is a set so that 𝜃d(𝑠)	=	A/s,	
	
        𝐺c(𝑠)	=	𝐾	and the disturbance input is 0.