Closed-loop response analysis of an inverted pendulum

This paper presents a locally stable nonlinear sliding mode control law for a rotary inverted pendulum with starting configurations above the horizontal line. An approximate nonlinear solution of the systems closed-loop loop dynamics during the sliding phase of the response is presented. The controller is tested experimentally and the approximate analytical solution is verified through comparison with the numerical solution. The nonlinear solution provides guidelines to select parameters that result in better controller performance.