Type-2 fuzzy-based fixed-time control for hypersonic morphing vehicles using dual-triggering mechanism

This paper addresses the attitude tracking issue for hypersonic morphing vehicles (HMVs) with disturbances and uncertainties. Hypersonic morphing vehicles utilize morphing wings to ensure cross-domain flights, which demands an attitude control system with strong robustness and high adaptation. First of all, the control-oriented model is developed for controller design, which includes the dramatic changes caused by the morphing wings. Secondly, a novel fixed-time disturbance observer (FTDO) is developed based on an interval type-2 Fuzzy logic system (IF2 FLS), which helps ensure strong robustness in cross-domain flights. Thirdly, the variable-exponent fixed-time control strategy is employed to build the control input, ensuring fixed-time attitude tracking. Then, a dual-event-triggering mechanism is established, which saves the system resources caused by signal transmissions. Unlike the conventional event-triggering mechanisms (ETMs), the developed dual- triggering mechanism (DTM) could achieve on-demand control and on-demand compensation. Finally, the closed-loop stability is proven via the Lyapunov stability theory, and simulation results validate the advantages.