Research On Trajectory Optimization And Tracking Guidance For High-speed Vehicle Under Multi-constraints

With the important application value in the military and civil fields,the high-speed vehicle has gradually becoming a research hotspot,as well as an important development object of the field of aerospace in the future.Therefore,this thesis focuses on the fast trajectory optimization with high precision and tracking guidance problems under multiconstraints for the high-speed vehicle.The main contributions of this thesis can be summarized as follows:A trajectory optimization method based on the improved hp-Radau pseudospectral method is studied.Firstly,the trajectory optimization problem is described as an optimal control problem,which can be transformed into a nonlinear programming problem by using the hp-Radau pseudospectral method.Then,the initial trajectory for the hp-Radau pseudospectral method is obtained by solving the transcendental equation of the polynomial trajectory generation algorithm,which can speed up the convergence speed of the hp-Radau pseudospectral method.Finally,the simulation results show the effectiveness of the proposed method.A trajectory optimization method based on model predictive static programming(MPSP)is studied.Aiming at the ascent trajectory optimization for the high-speed vehicle in a complex flight environment,an improved GS-MPSP(IGS-MPSP)algorithm is proposed,which can not only deal with the constraints related to state and control vector,but also retain its high computational efficiency.The spectral representation technique is used to describe the control variables,which reduces the number of decision variables and makes the control smooth enough.Through Taylor expansion,the constraints are transformed into an inequality containing only decision variables,so that they can be added into the GS-MPSP framework.By the Gauss quadrature collocation method,only a few collocation points are needed to solve the sensitivity matrix,which greatly accelerates the calculation.Subsequently,the analytical expression is obtained by combining the static optimization with the penalty function method.Finally,the simulation results demonstrate that the proposed IGS-MPSP algorithm can achieve high terminal precision under the constraints,and have high computational efficiency.An adaptive tracking guidance method based on tracking model predictive static programming(T-MPSP)is studied.Firstly,a parameter identification strategy based on the extended Kalman filter algorithm was designed to modify the model online.Secondly,an improved T-MPSP algorithm is proposed,which provides the original T-MPSP algorithm with the ability to handle the constraint of control.Subsequently,an adaptive tracking guidance algorithm is designed to track the altitude,speed and flight path angle of the vehicle by combining the two algorithms.Finally,simulation results demonstrate the feasibility and robustness of the proposed tracking guidance algorithm.