Ascent Phase Trajectory Optimization And Tracking For Hypersonic Vehicles

Consider of all constraint conditions and interference factors, we use X-33aircraft as a model for ascent phase trajectory optimization and tracking ofhypersonic vehicle.Firstly, we establish the motion equations of aircraft in the vertical plane, anduse the public data to fit the high accuracy of the aerodynamic model, and analys theconstraint conditions during ascent phsase of hypersonic vehicle. on that basis,height–speed climb corridor can be easily designed. Meanwhile, we summarizes thebasic principles of Gauss pseudospectral method and the implementation methods,analyse and study the impact of the initial value estimation and the selection ofcollocation number for the trajectory optimization.Then, we improve the the initial value estimation and collocation numberselection to optimze the ascent phase trajectory using fuel at least. The optimizationresults show that the improvement of the initial value estimation and collocationnumber selection can get a relatively precise trajectory in a short time, and itsfeasibility is verified. In addition, Trajectory optimization constraints need to beincreased using Gauss pseudospectral method for segmentation trajectoryoptimization, then based on the the most saved fuel flight program we optimize anddesign the climing after accelerating flight program. Meanwhile, we design theavoid obstacles flight program.Lastly, Taking consider of kinds of interference factor, the influence for theflight reference trajectory is analyzed. And we adopt an guidance rate based oncontinuous-time predictive control to track the flight reference trajectory of theascent phase trajectory using fuel at least an and the obstacles trajectory. Comparedwith the open-loop guidance.