Trajectory Optimization And Guidance Law Design Of Pneumatic Aided Trajectory

Aeroassisted orbiting vehicles,in orbital shift missions,some of their orbital orbits are located inside the atmosphere,and the aircraft can use gas power to assist it in orbital shift missions.The orbit of the aeroassisted orbiter is optimized through an algorithm,which enables the aircraft to complete the orbiting task with lower energy consumption.This also makes the pneumatic assisted orbiter more powerful than the ordinary orbit transfer aircraft,capable of performing tasks on the track for a longer period of time,and having a larger payload.In this paper,the optimization of the trajectory optimization and the closed-loop guidance law in coplanar and non-planar cases are mainly carried out.At the same time,simulations are performed using MATLAB.In this paper,the trajectory optimization problem of the orbit transfer vehicle is mainly divided into two cases.One is the case of the transition from the high orbit to the low orbit of the same plane,and the other is the transition from the high orbit not in the same plane to the low orbit..In this paper,the trajectory optimization task profile is designed in trajectory optimization.The necessary models and constraint conditions are deduced for the same-plane and different-plane transitions.Considering that the trajectory optimization problem is actually a complex nonlinear optimization problem,this paper uses Gaussian pseudospectral method to optimize it.Considering the robustness of the trajectory optimization algorithm,the difference between the actual aircraft model and the design model,and the uncertainty of the atmospheric density during actual flight,the design of the closed-loop guidance law for the orbit transfer aircraft during the flight in the atmosphere is designed.At the same time consider how to achieve the guidance law of the actual aircraft.This paper mainly focuses on the zero-order guidance law and the first-order guidance law in the guidance law of the design.After simulation,we can find that the higher order guidance law can have better robustness and can still have a good guidance effect under the condition of greater atmospheric density fluctuations.At the same time,after comparison,guidance using a higher order guidance law can achieve higher end speeds and more fuel savings.Finally,the problem of how to achieve the guidance law in real aircraft is considered and verified by simulation.