State dependent riccati equation based model reference adaptive control design for nonlinear systems

A new model reference adaptive control (MRAC) algorithm is presented for a class of nonlinear systems. The proposed MRAC method uses a nonlinear reference model whose controller is designed by using the so-called State Dependent Riccati Equation (SDRE) techniques. The controller designed for the nonlinear reference model is then adapted for the (presumably unknown or uncertain) nonlinear plant dynamics, again by using the SDRE methodology. The proposed methodology is exemplified by using the simulation model of an inverted pendulum, showing the effectiveness of SDRE-based MRAC for nonlinear systems.