Dynamic Analysis And Control Of The Supporting Mechanism Of Parabolic Cylindrical Deployable Antenna

With the rapid development of aerospace industry,the application of satellite antenna in communication satellite,meteorological satellite,electronic reconnaissance satellite and other satellites has been strengthened.Therefore,the deployable antenna with large-aperture,high-precision,high storage ratio and high gain has become the focus of the research of major Aerospace countries.In this paper,the large deployable parabolic cylindrical antenna supporting mechanism is taken as the research object,and its kinematics,dynamics analysis and optimal control are studied theoretically.In this paper,firstly,the working principle of parabolic cylindrical deployable antenna is studied.The unit module of antenna supporting mechanism is divided,and then based on the four-link mechanism and the geometric parameters of each rod,the position relationship of the components in the unit module and the expressions of rotation angle and slide displacement are derived.Then,the kinematic model of the whole antenna support mechanism is established through the combination of modules and D-H method,and the theoretical solution is carried out with MATLAB software,and the motion trace diagram of the antenna support mechanism in the deployment process is obtained.In order to study the stability of the supporting mechanism of the parabolic cylindrical deployable antenna,the finite element model of the closing and deployment state of the supporting mechanism is established for its state in the process of transportation and in orbit work,and the modal analysis under different working conditions is carried out.The frequency response analysis is carried out for the finite element model of the antenna supporting mechanism in the unfolded state,and the vibration condition under the load is analyzed.In order to better grasp the dynamic characteristics of the supporting mechanism of the deployable parabolic cylindrical antenna in the process of deployment Based on the Lagrangian Equation method of the Second Kind,the rigid body dynamics model of the antenna supporting mechanism is established,the dynamic characteristics of the module under constant force are obtained and compared with the simulation results of ADAMS.The correctness of the natural coordinate method and the absolute node coordinate method in the rigid flexible coupling dynamic modeling is verified by the examples of the flexible simple pendulum and the rigid flexible coupling double pendulum.Then,the rigid flexible coupling dynamic simulation of the "Japanese" deployable antenna support mechanism in ADAMS is carried out to verify the feasibility of its deployment and analyze the dynamic characteristics during the deployment process.Finally,aiming at the problem that the antenna supporting mechanism is vulnerable to be affected by the impact during the deployment process,a design method of optimal time jerk deployment trajectory is proposed.Based on the cubic spline interpolation method,the optimization model of antenna deployment trajectory is established,which is the comprehensive optimization of deployment time and system jerk.The NSGA-II algorithm is improved by introducing the expected solution retention strategy,which solves the problem that the optimal solution in the multi-objective optimization process is difficult to be fast and stable.The optimization model is solved efficiently,and the optimal trajectory is obtained.