Design of robust linear regulator with prescribed trajectory insensitivity to parameter variations

For a linear, time-invariant system that is subject to parameter variations, a method is proposed for designing a fixed-feedback controller which achieves a specified insensitivity, of the closed-loop trajectory to the parameter variations. This method differs from those presented in earlier papers in that it controls the actual trajectory variations over the range of parameters instead of dealing with differential sensitivities. The sensitivity problem is solved by posing it in terms of the optimization of a linear regulator with a quadratic performance index.