Ascent Trajectory Optimization of Aerospace Vehicle

The trajectory optimization problem is a kind of optimal control problem.Conventional direct and indirect methods are sensitive to the initial values.In order to optimize the ascent trajectory of aerospace vehicle,a combined optimization method was used.First,direct shooting method was used to convert the trajectory optimization problem into a nonlinear programming(NLP) problem,and then the NLP problem was solved by genetic algorithm to get initial guesses.Second,pseudo spectral method was used to transform the trajectory optimization problem into a NLP problem,and then sequential quadratic programming was used to solve the NLP problem with initial values from genetic algorithm.It is shown that the combined method is effective for the solution of trajectory optimization.