A Robust Adaptive Control Design for Gliders Subject to Actuator Saturation Nonlinearities

Range, endurance and cross-country speed of a glider can be considerably improved by efficient soaring methods. Recent static soaring research assumes known linear glider dynamics which do not change with flight conditions, and the mechanical limits such as actuator saturation nonlinearities are simply ignored. In this paper we allow large parametric uncertainties in the dynamics of the glider as well as actuator saturation limits. We propose a robust adaptive linear quadratic (LQ) control design with an adaptive anti-windup compensator to handle both the unknown time varying parameters and the saturation nonlinearities. We demonstrate that the glider tracks the optimal soaring trajectory generated by our decision algorithm despite the parametric uncertainties and the control input constraints.