| In order to reduce the vibration and pose change of small satellites caused by disturbances,and to ensure that their space mission control algorithm is correct,it must be conduct with loaded simulation experiments on the ground.At present,small satellite ground simulation mainly using air floating platform as semi-physical simulation both at home and abroad,no installation of flexible appendages overall satellite simulation,especially dynamic load simulation method flotation platform has not yet publicly reported in the literature.Aiming at the limitations of the satellite simulation on the ground,this paper puts forward a kind of dynamic load simulation method of 5 DOF air floating platform.This method is used to deeply research and validate the control algorithms of orbit and attitude of small satellite under the effect of spacial disturbances.It uses methods of air floating and hanging for gravity compensation of the five DOF air floating platform on which flexible solar wings have been installed.At the same time,It apply a non-contact and position following load on the flexible solar wings to simulate the disturbances in space.The method proposed in this paper make it available that the satellite with flexible attachment as a whole be used for experiments under spacial disturbances on the ground,it is of great significance to suppress the vibration of flexible attachment and strengthen the stability of the position of satellite under spacial disturbances.First,the dynamic load simulation system of the five DOF air floating platform were summarized.In the text,the required components of the dynamic load simulation system have been introduced.In addition,the ground console and the position identification method of the air floating platform have been introduced.The coordinate systems have been established in the text to describe the sport of air floating platform,and the kinematics equations of five degree of freedom air floating platform has been set up according to the transformation matrix derived from the Euler angles method and the coordinates of the geometric equation of the platform.And the dynamics equation of the air floating platform is derived based on the theory of mechanics and the modal equation on ideal situation.It is a theory foreshadowing for the scheme of the dynamic load simulation system and is of important guiding significance to determine the scheme of dynamic load simulation method.Secondly,the scheme of dynamic load simulation method of five DOF air floating platform has been puts forward in this this paper.In the text,the position follow system,the constant force hang mechanism,the loading manipulator and air injection system have been detail designed and analyzed.A wide range of following mechanism based on the coarse following and precise following systems has been put forward,and the constant force hang mechanism that can adapted to wide-ranging luffing of the solar wings has been inventive designed.The loading method chooses a plane loading manipulator which has three joints,and the trajectory planning and calculation of locations of loading manipulator in the process of loading have been expounded.What’s more,the simulation analysis of the spray force of the nozzle has been carried out in Fluent software,and the design sizes of the nozzle has been determined.Moreover,the error models of all the parts of the loading method have been established and analyzed,and the corresponding measures of how to improve the precision of the system have been given.The error models of monocular vision system and the strapdown inertial navigation posture recognition system have been established,the methods of reduce the errors have been analyzed.The four level inverted pendulum model of the position following system has been established,and qualitative analysis of the position following error has been done.The errors introduced by various affecting factors of hanging force and the introduced horizontal interference force have been quantitative calculated and analyzed.The loading errors of the loading manipulator have been analyzed.Finally,the rigid-flexible coupling model of the 5 DOF air floating platform has been establish combined with Ansys and Adams softwares.Besides,the loading method has been simulated and analyzed,and the feasibility of the loading method has been proved by the simulation results. |
