A new method is developed for stabilizing motion on collinear libration point orbits using the formalism of the circular restricted three body problem. Linearization about the collinear libration point orbits yields a...A new method is developed for stabilizing motion on collinear libration point orbits using the formalism of the circular restricted three body problem. Linearization about the collinear libration point orbits yields an unstable linear parameter-varying system with periodic coefficients. Given the variational equations, an innovative control law based on characteristic exponent assignment is introduced for libration point orbit maintenance. A numerical simulation choosing the Richardson's third order approximation for a halo orbit as a nominal orbit is conducted, and the results demonstrate the effectiveness of this control law.展开更多
A method for spacecraft formation flying (SFF) design and control near libration point orbits was developed by making use of the Floquet theory for periodic orbits. Firstly, the Floquet theory used in libration point ...A method for spacecraft formation flying (SFF) design and control near libration point orbits was developed by making use of the Floquet theory for periodic orbits. Firstly, the Floquet theory used in libration point orbits was introduced and the coefficients of four Floquet periodic modes were proved to be nearly constant when the amplitude in z direction of earth-moon L1 halo orbits is less than 20000 km. On this basis, a configuration design approach to SFF in L1 halo orbits was proposed, and several types of special configurations were obtained with periodic mode 3 and mode 5 or mode 4 and mode 6. Then, in order to control the SFF configuration concisely, those coefficients of the 5 modes (except the stable one) must be kept constant. A stationkeeping method for SFF was developed, which controls 5 Floquet modes simultaneously. Finally, simulations showed that the Floquet-based approach of configuration design and control for SFF is effective, simple and convenient. The research may be of value for deep space explorations.展开更多
基金supported by the National Natural Science Foundation of China(10702003)
文摘A new method is developed for stabilizing motion on collinear libration point orbits using the formalism of the circular restricted three body problem. Linearization about the collinear libration point orbits yields an unstable linear parameter-varying system with periodic coefficients. Given the variational equations, an innovative control law based on characteristic exponent assignment is introduced for libration point orbit maintenance. A numerical simulation choosing the Richardson's third order approximation for a halo orbit as a nominal orbit is conducted, and the results demonstrate the effectiveness of this control law.
基金supported by the National Natural Science Foundation of China (Grant No. 10702078)the National University of Defense Technology Research Program (Grant No. JC08-01-05)
文摘A method for spacecraft formation flying (SFF) design and control near libration point orbits was developed by making use of the Floquet theory for periodic orbits. Firstly, the Floquet theory used in libration point orbits was introduced and the coefficients of four Floquet periodic modes were proved to be nearly constant when the amplitude in z direction of earth-moon L1 halo orbits is less than 20000 km. On this basis, a configuration design approach to SFF in L1 halo orbits was proposed, and several types of special configurations were obtained with periodic mode 3 and mode 5 or mode 4 and mode 6. Then, in order to control the SFF configuration concisely, those coefficients of the 5 modes (except the stable one) must be kept constant. A stationkeeping method for SFF was developed, which controls 5 Floquet modes simultaneously. Finally, simulations showed that the Floquet-based approach of configuration design and control for SFF is effective, simple and convenient. The research may be of value for deep space explorations.