Optimal Closed-loop Ascent Guidance For Aerospace Vehicle

The development of Aerospace vehicle represents the scientific andtechnology strength of a country. It’s also the foundation for human toexplore the space. And, the guidance problem of the aerospace vehicle isthe key of the key. With the development of technology, traditionalopen-loop guidance begins to show its disadvantages, the closed-loopguidance becomes the tendency. The closed-loop guidance is to generatean optimal trajectory online within a guidance cycle, based on the currentposition and velocity. The closed-loop guidance will compensate the errorscaused by any unexpected reason, thereby it will greatly improve theaccuracy.This dissertation gives a general explanation to the background ofclosed-loop guidance and shows some basic theories which are applied inthis area, for example, the definition of the coordinates, motion equations.In the solution of an optimal trajectory problem, we always transformit into a two point boundary value problem(TPBVP). In this dissertation,we select finite difference method to solve such a TPBVP, with an initialguess created by the direct-method existed, a simulation is made with theGHAME model. The result shows that its rapidity maintains therequirement of the closed-loop guidance.Moreover, this dissertation elaborated the design of the real-timesimulation system, which could accomplish the real-time simulation of theclosed-loop flight procedure of aircraft in the laboratory environment withquite a low cost. The simulation result shows that with correspondedtrajectory optimal method, the system could completely meet the demand of the real-time performance for closed-loop guidance.At last, the dissertation summarizes the work and proposes thepossible future research.