H-INFINITY AND H-2 SIMPLE CONTROLLERS FOR ROBOTIC APPLICATIONS

A new method is discussed which allows one to synthesize continuous-time controllers of lead/lag or PID type that are optimal both in the H infinity and H-2 sense (equalizing H-2 controllers), for a restricted class of systems well suited for robotic applications. In particular, conditions on the plant are given so that the optimal controller has a lead/lag or PID structure in cascade with an additional low-pass filter. The method is applied to synthesize a PI controller for the velocity control of one joint of an electrically actuated industrial SCARA robot.