Fixed-time observer-based heading control of a paraglider recovery system with input saturation

This paper investigates a challenging heading control problem for a flexible paraglider recovery system with input saturation. A fixed-time observer-based control approach is presented. In this approach, a fixed-time disturbance observer is preliminarily designed to estimate the aerodynamic uncertainties and the complex coupling of the subsystems. A fixed-time auxiliary system is then proposed to compensate for input saturation impact. With the application of the estimated and compensation values, a novel heading tracking controller is synthesized with compensated disturbance. The key feature of the scheme is that it is not only fixed time stable regardless of any initial state, but also it prevents control performance degradation due to input saturation and various disturbances. Simulation results verify the effectiveness of the proposed method.