Gust load alleviation of aircraft with multiple control effectors in the cruise phase based on L1 adaptive nonlinear dynamic inversion and control allocation

An aircraft is often inevitably affected by the wind in the cruise phase, as a result an additional overload will be generated at the aircraft fuselage and make passenger uncomfortable and airplane vibrating. Because most of the civil aircrafts also have high aspect-ratio, the elasticity of plane is also large. For some high quality flight phases, the gust load alleviation would also make the tracking accuracy of airplane be better. Due to the drawback of nonlinear dynamic inversion (NDI), which cannot cancel the system uncertainties efficiently, a nonlinear L1 adaptive dynamic inversion control method is proposed in this paper. The L1 controller is made of a static feedback controller and an adaptive controller. The static state feedback provides the inner-loop stability and desired closed-loop characteristics, and the adaptive controller is used to compensate the uncertainties of system. The discrete gust and Dryden turbulence wind are simultaneously employed into the wind model. The simulation results revealed that the GLA controller we built is effective and robust.