... of the nonlinear optimal controller an algebraic Riccati equation is being solved repetitively, at each iteration of the control algorithm. The global stability properties of the control method are proven through Lyapunov analysis. Research limitations/implications Because of the coupling between the torque...

... is designed. This controller achieves the solution of the optimal control problem under model uncertainty and disturbances. Findings To select the feedback gains of the nonlinear optimal (H-infinity) controller, an algebraic Riccati equation has to be solved repetitively at each time-step of the control...