Online Fast Sliding Mode Controller for Air-Breathing Hypersonic Vehicle with Inlet Constraint

Based on prescribed performance control, an online fast terminal sliding mode controller (OFSMC) and an online extraction method of performance constraints parameter are proposed for air-breathing hypersonic vehicles (AHV) with considering inlet airflow constraint. Firstly, in order to limit the transient and steady-state performance of tracking error, a performance function is designed for the angle of attack, which can accurately converge to the steady-state value at the set time. Secondly, the constrained tracking error of the angle of attack is converted without constraints. Then, based on the method of terminal sliding mode control and the improved reaching law which could convergent in finite-time, OFSMC is designed to limit the range of angle of attack to achieve the engine inlet constraint. Considering the difficulties in obtaining the parameters of constraint performance for AHV, an online index database system (OIDS) was built for querying performance parameter, using the method of deep forest. Thirdly, an optimization algorithm for AHV is presented to obtain the training database based on NSGA-III. The optimized performance parameter is composed of the tracking error, chattering of controller, controller instruction and the value of angle of attack. Finally, two simulations for AHV are performed to verify the effectiveness and superiority of the method proposed.