Study On Rapid Maneuver Of Spacecraft Based On Variable Thrust Liquid Rocket Engine

With the fast development of space technology, especial the military spaceflight, the requirements for spacecrafts with rapid maneuver ability become more and more intense, especially in space security which contains companion flight and monitoring, nearing to interfere, rendezvous and docking, spatial interception, capturing on orbit, and so on. These tasks require thrust change neatly and rapidly. However, as the space-borne variable thrust propulsion system which used in rapid maneuver is not completed, people jointed several steady thrust propulsion systems to achieve some simple varieties of thrust. That is the restriction to fulfill the rapid maneuver of large space, high precision, and low consumption. This paper studied on rapid maneuver of spacecraft based on variable thrust liquid rocket engine.This paper studies the feasibility and the program of rapid maneuver of spacecraft based on variable thrust liquid rocket engine systematically. Firstly, the principle, components and control of variable thrust rocket engine are discussed. Then, the regulating ways and the adoptable technologies of thrust are studied, and the applications in astronavigation are analyzed. Secondly, the variable thrust dynamics model for rapid maneuver is built. And the control law based the classic Lyapunov stability control method is also built. Thirdly, the rapid maneuver problem, which is also a two-point boundary value problem, is translated into an optimum control problem. Then, the optimization model is built, and the dynamic optimization problem is translated into a static optimum problem to do numerical calculation. Fourthly, the two optimization methods for trajectory optimization are compared and analyzed. And the Multi-method Collaborative Optimization Algorithm (MCOA) is chosen to solve the rapid maneuver problem based on variable thrust.Based on these studies, several 2-D and 3-D cases of rapid maneuver are simulated and analyzed. The requirements for continuous and variable thrust on rapid maneuver spacecraft are studied in quantitative angle, and the applications of variable thrust rocket engine in astronavigation are analyzed. The analytical results show that the thrust changed continuously by time in orbit coordinate system's three axes. That demonstrates that thrust changing continuously is the essential requirement in rapid maneuver. Meantime, it verifies the variable thrust rocket engine is very important to rapid maneuver.This paper studies on rapid maneuver of spacecraft based on variable thrust liquid rocket engine comprehensively and systematically from assignment requirements, technological base, optimization model and solve method. It would have the benefit reference for the development of variable thrust rocket engine and new concept of space maneuver vehicle.