CLASSICALLY RATIONALIZED LOW-ORDER, ROBUST STRUCTURAL CONTROLLERS

An experimental and analytical comparison of classically rationalized and optimal control design techniques is conducted. Classically ration alized compensators blend the Loop assignments, complex topological de sign, and robustness of optimal controllers and the lower order, robus tness, and practical insight of classical controllers. The single-inpu t/single-output disturbance rejection problem for controlled structure s is divided into four distinct topologies, and optimal controllers ar e designed and interpreted classically, The observations are then summ arized into a set of design rules for the design of low-order robust c ontrollers. Classically rationalized and robust compensators are exper imentally implemented on the Middeck Active Control Experiment, a Shut tle Eight experiment that flew on STS-67 in March 1995.