Obrit Design And Control Of Two Satellites Formation Task In Lunar Exploration

Since twenty-first Century,the enthusiasm for exploring the moon has continued to rise.At the same time,with the development and application of satellite formation technology,the superiority of satellite formation is further demonstrated.In this paper,a design method of Earth Moon transfer track based on conical curve splicing is proposed,and the configuration control of double star formation under the large elliptical orbit of the moon is studied.The main work is:Firstly,the relative dynamics modeling method of double satellites formation is studied theoretically,and the influence of the perturbation of the moon's gravitational field on the relative motion of the formation is analyzed.The definition of the detector window and the time window of the lunar probe near the month are described.The measurement and control constraints and light constraints affecting the near point time window are modeled and analyzed.A fast calculation method of the lunar near month point time window is proposed.The simulation analysis of the near month point window in May 2018 is done.The influence of the measurement and control conditions and the energy constraints on the near point time window are analyzed,and the illumination conditions are analyzed.The influence of constraints on the orbit around the moon is obtained,and the characteristics of the orbit around the moon under optimal illumination are obtained.Secondly,based on the characteristics of the near point time window and the target orbit,a method of Earth Moon transfer trajectory design based on conical curve splicing is proposed.The algorithm of orbit design is elaborated in detail.Under the constraint conditions of the condition of the launching field,the requirement of the target orbit task,the orbit dynamics and so on,the method is analyzed.Iterating the orbit parameters that affect the entry point of the moon,the calculation method of the Earth Moon transfer orbit parameters is obtained,and the corresponding calculation formula is given.Based on the variable mass and constant thrust model,the orbit correction strategy and the orbit maneuver strategy in the near month capture section are established under the influence of the orbit error and the space perturbation.The simulation results are verified by STK.Furthermore,the configuration and control strategy of the two star formation under the large elliptical orbit of the moon are established,and a linearization method is proposed for the kinematic model of the satellite formation under the large elliptical orbit,and the relative kinematic equations of the satellite formation with the true near angle as the independent variable are obtained.On this basis,a sliding mode control law with real near angle as independent variable is designed for the control of formation configuration.The relative motion of satellite formation under sliding mode control is simulated and analyzed respectively,and the effectiveness and applicability of the sliding mode control law are verified.