Research On Control Allocation Of Aircraft With Heterogeneous Redundant Actuators

This paper takes a hypersonic vehicle which has heterogeneous redundant actuators as the research object and addresses the control allocation of aerodynamic surfaces and reaction control system as to the reentry attitude model of the hypersonic vehicle.Firstly,considering most of the existing control allocation algorithms are based on the assumption of the static relationship between actuator deflections and moments,a new dynamic control allocation method is proposed.The dynamic information of actuators is added to the static control allocation which can be described as a quadratic programming problem,in order to build the dynamic control allocation model.Linear matrix inequality is used to transform the quadratic programming problem into an objective function minimization problem,aiming to improve the effectiveness and accuracy of control allocation.Secondly,on the basis of the research results of dynamic control allocation,a weight-varying control allocation scheme is presented to overcome the allocation low efficiency for saturated actuators.The nonlinear control allocation law of mixed optimization is linearized through taking the weight coefficients matrix inequality,in the case of neglecting actuator dynamic or not,respectively.Research results show that the scheme can not only make full use of the redundant control performance of the actuators,but also reduce the delay and attenuation of the control quantity caused by the actuator dynamics.Finally,for maximum using of aerodynamic surfaces,reducing the reaction control system's fuel consumption,and guaranteeing the fault reconfiguration ability,a mixed programming fault-tolerant control allocation method is involved.The moment between aerodynamic surfaces and reaction control system is allocated by daisy-chained,satisfying the reaction control system doesn't start until aerodynamic surfaces are saturated.The quadratic programming is used to allocate the moment between aerodynamic surfaces.The selecting switch jets of reaction control system are calculated by 0-1 integer linear programming.When failures occur,observers are designed for the actuator dynamics to estimate the failure information.According to the failure information,a fault-tolerant control scheme based on control allocation is proposed to ensure the system stability.