Robust Gain-scheduling Control Of UAV With Parameter Varying In Large Scale

As the development of Unmanned Aerial Vehicles(UAVs)technology,there have been many new kinds of UAVs,in some cases,the flight parameters may vary greatly,the flight parameters include the external conditions such as flight envelope-flight altitude and Mach number and the attack angle,as while as the internal parameters such as configurations and aerodynamics.The morphing wing UAV(MUAV)and high altitude long endurance UAV(HALE UAV)and hypersonic UAV are typical cases.The variations are often nonlinear with uncertainties,which make a great challenge to the traditional flight control method such as the gain-scheduled(GS)PID control.The traditional GS control is originally “EngineeringOriented”,which is usually valid for applications with slow parameter variation but can't guarantee the stability and robustness in theory for parameter variation in large scale.Combining the traditional robust GS control with linear parameter varying(LPV)system,the robust GS control provides a potential way for the case which is beyond the ability of the traditional GS control.But it's noticed that in the most control practice,the traditional GS PID control is still used,while the robust GS control method is rarely used.It's because that most of current robust GS control methods produce controllers too complex to implement.This paper used the morphing wing UAV(MUAV)as the main research object to do research work on robust GS control problem.The robust GS control theory is studied,focusing on improving the practicability,and then used the proposed practical robust GS control solution in the transient mode control of the MUAV and fault-tolerant control for the faulty UAV with single aileron jamming at ultimate point.The main research contexts are as bellows:1.The modeling problem of MUAV is investigated.The nonlinear model in six degree of freedom is setup based on which the LPV system model is derived using an improved function-substitution method proposed in this paper.The dynamics effection in the morphing process is also analyzed based on the model to build the foundation for control design.2.To overcome the disadvantages of traditional GS control,the robust performance constraint is introduced and the multi-objective evolutionary algorithm(MOEA)is researched in the improved GS control method.The method is also applied on the transient mode control of MUAV.3.A robust LPV-PID control method based on the LPV based robust GS control and GS PID control is proposed and researched.The static output feedback(SOF)control is extended to LPV system,and the robust LPV-PID control is derived using the system transformation and structured structural matrix.An algorithm combining the iterative linear matrix inequalitis(LMIs)and MOEA is researched and applied to solve the bilinear matrix inequalities(BMIs)arose from the LPV-PID control design.4.The fault tolerant control problem of single aileron jamming at ultimate point is researched and solved by the robust LPV-PID control method proposed in the above section.An adaptive sideslip command generator and an inner loop sideslip controller is designed,the latter is designed using the robust H? LPV-PID method proposed by this paper to validates the method for fault tolerant control.In which the innovations made in this paper are as follows:1.An improved function-substitution modeling method for LPV system is proposed and applied on the model of MUAV.By introducing partial linearization into functionsubstitution method,the varying parameters can be chosen freely and number of varying parameters can be reduced.2.A new GS PID control design framework is proposed and applied on MUAV in the transient mode control.Robust performance index is used as the constraints and objective in the parameter-optimization process so that MIMO system can be treated and the robust constraints can be applied more intuitively.An decompose-based MOEA called MOEA-D is proposed and applied to optimize the control gains in the design,which is more time efficient with better performance than the widely used MOEA called NSGA-II.3.LPV based H? robust GS PID control method is proposed and researched.By extending static output feedback control to LPV system and introduce the structural matrix,the design method of robust GS PID controller for LPV system is given.And a solution combining the iterative LMI and MOEA is proposed to solve the BMIs in the control design.4.A new fault tolerant control method for single aileron jamming at ultimate point is proposed.The core idea behinds this method is to use sideslip to compensate the asymmetric roll moment caused by the jammed aileron.The sideslip controller is desgined using LPV based robust GS PID control method proposed in the above section.In a word,this paper mainly researches the LPV based robust GS control,both in theory and application.By combining the LPV based robust control and traditional GS control,two different robust LPV-PID design methods are proposed,and some issues arose such as BMI solving and multi-object optimization are researched.The proposed methods are used in the transient mode control of MUAV and fault tolerant control in case of single aileron jamming at ultimate point,and the result shows that the proposed solutions are valid and efficient.