Reentry Trajectory Optimization Using Sequential Quadratic Programming
Yongji Wang · Aerospace Control · 2009
Sequential quadratic programming for trajectory optimization of reentry vehicle is proposed.Firstly,Equations of motion are normalized and an independent variable is introduced to reduce the difficulty of iterative computation.With the angle of attack and the bank angle as control variables,the optimal control problem is set to minimize heat index,considering strict process and terminal constraints.And then,by choosing states and controls of discrete nodes as parameters,the optimal control problem is transformed into a nonlinear programming problem using direct collocation method.Finally,sequential quadratic programming is presented for solving the nonlinear programming problem.According to the sensitivity to initial value in trajectory optimization for reentry vehicles with multi-constraint,this paper develops a rapid reference trajectory programming strategy.Simulation results show that the optimal trajectory can consistently achieve the desired target conditions within allowable tolerances and satisfy all the other constraints effectively.