Research On Fault-tolerant Control Method Of Hypersonic Vehicles Based On Predictive Control

As hypersonic vehicle has the feature of fast speed,strong penetration ability,so it has good application prospects in military affairs and civilian use.The strong non-linear,coupling features of hypersonic vehicle dynamic model lead to parameter perturbation,which have great difficulty for controller design.But make the high maneuver performance requirements of the mission in the complex environments,and the frequent maneuver will make the system components failure.In order to guarantee the vehicle tracking stable and accurately finish the task,it is of great importance to develop reliable and efficient integrated solutions to meet the design requirements of control system becomes the emphasis in this paper.Therefore,starting from these problem,hypersonic vehicle longitudinal cruise period of dynamic model is as the research object.The following aspects are carried out:Considering the longitudinal dynamic model of hypersonic vehicle suffering with elevator deflection drifting fault and parameter perturbation,a continuous predictive fault-tolerant controller is constructed to assure the tracking ability of the flight system after faults.Firstly,the input-to-output feedback linearization model of the vehicle with faults is employed and the extended state observer is designed to estimate the higher derivatives of vehicle and altitude and the lump uncertainties resulted from elevator deflection drifting fault and parameter perturbation online.Finally,in the precondition of the system's stabilization,the Taylor expansion is taken as the predictive model to the analytical solution of the control law.While the elevator deflection is suffered with stuck fault or damage fault,a novel fault-tolerant control approach is approved combining with the extended state observer and predictive control.When the one is subjected to stuck fault for the two-piece elevator hypersonic vehicle model,or when the elevator deflection suffered with damage fault,Input-to-output feedback linearization model of hypersonic vehicle is employed to design the extended state observer.And the predictive controller is then constructed based on the Taylor expansion.Considering the given instruction may not subject to the dynamics characteristics of the vehicle,or when the elevator deflection failure occurs,the serious phenomena of the actuators saturation appeared.Therefore,considering the large span motor task in the process of hypersonic vehicle longitudinal cruise with the elevator deflection drifting fault,stuck fault or damage fault,a feasible and effective design system aboutintegrated fault-tolerant control based on hierarchical predictive control is approved,namely double coordination integration control structure.In order to make the aircraft rapidly and accurately track feasible trajectories with states and control inputs limitation,the direct collocation method is introduced to construct the feasible trajectories.Then,the extended state observer is designed based on the input-to-output feedback linearization model of hypersonic vehicle.The Taylor expansion is employed as the predictive model,and a novel predictive controller is constructed.