I had to use state-variable feedback to design a control system for a motor. I first designed a deadbeat controller, which was pretty easy. But now I have to design another controller using root locus methods. The gain that is varied is located in the feedback loop as shown in the picture. I am completely lost as to how to generate a root locus with the gain in the feedback loop. Can anybody give me a general form to get into so I can draw the root locus?