In-Flight Validation of a Robust Flight Controller Featuring Anti-Windup Compensation

Abstract

In-flight demonstration and verification of a robust flight control design including an advanced anti-windup strategy is presented in this paper. The test aircraft, an Ultrastick 120 unmanned aircraft, is equipped with a pitch- and roll-attitude command flight-control system for remotely controlled augmented flight. The longitudinal aircraft dynamics are enhanced with an H1-based control design. The controller additionally comprises an dvanced anti-windup strategy to avoid integrator windup during actuator saturation. The lateral axis features a linear-parameter varying controller which provides robust performance over the whole velocity range. The controllers as well as the anti-windup algorithm are verified and validated in a non-linear simulation environment and by various flight tests. The paper provides detailed insight in the design process of the controllers, as well as a comprehensive discussion on the simulation and flight test results.