Prescribed-Time-Performance-Based Attitude Tracking Control for Fixed-Wing UAVs With Input Amplitude and Rate Constraints

This paper proposes an attitude tracking control scheme for fixed-wing unmanned aerial vehicles with state, input amplitude and rate constraints, which is able to guarantee the prescribed-time prescribed performance. Firstly, a novel modified prescribed-time performance function is proposed to balance input and performance constraints, with its boundary adaptively adjusted according to the input saturation errors. Secondly, considering the input saturation that occurs during actual flight, an error transformation function and a hyperbolic tangent function are employed to address input amplitude and rate saturation, which prevents abrupt variations in input amplitude. Thirdly, a parameter adaptive estimation method is adopted to approximate the upper bound of external disturbances. On this basis, a back-stepping control method is investigated to guarantee that tracking errors meet the performance boundary within prescribed time under multiple constraints. Comparative simulations illustrate the effectiveness and merits of the proposed control scheme.