Fuzzy logic based flight control system for hypersonic transporter

A fuzzy logic based flight control system for a hypersonic transporter is proposed, in order to provide the longitudinal stability in the hypersonic region and to improve the response of the vehicle as well as to make the response exactly follow the commands. The construction of the fuzzy logic controller is set up, in which angle of attack and pitch rate are chosen as input linguistic variables, and the deflection of the elevator is the control variable. Fourteen fuzzy inference rules, which are designed to model a human operator's behaviour, are employed, and the fuzzy algorithm of maxmin composition is used as an inference mechanism. Performance evaluation of the fuzzy logic controller for the hypersonic transporter is carried out at four flight points, which are chosen from the whole flight envelope. The calculation results show that the fuzzy logic controller has a good ability to stabilize the vehicle in the hypersonic region, and is fairly robust across the flight envelope.