1993 Volume 6 Issue 10 Pages 462-470
For nonsquare plants, we propose a method for designing optimal tracking and servo systems based on quadratic performance indices. It is assumed that the number of inputs of the plant is greater than that of outputs. In this case, the steady-state input achieving a specified reference signal at the output is not unique. We utilize this freedom to improve the transient behavior of tracking. The optimal control laws are composed of state feedback with an optimal regulator gain, feedforward of the reference signal, and a constant term determined by the initial state of the system. The constant term is not needed if we assume that the change of the reference signal occurs only when the plant is in a steady state.