Robust nonlinear feedback control of discrete-time nonlinear systems with mixed performance criteria

A novel nonlinear state feedback control design is presented for discrete-time nonlinear systems and mixed performance criteria. The purpose behind this new approach is to convert a nonlinear system control design into a convex optimization problem involving state dependent linear matrix inequality solutions. By solving the inequalities at each time step, the optimal control solution is found to satisfy mixed performance criteria guaranteeing quadratic optimality with inherent stability property in combination with H_∞ or a passivity type of disturbance reduction. The effectiveness of the proposed technique is demonstrated by simulations involving the control of a benchmark mechanical system.