Design And Research Of Sidemounted Tracking Platform

With the rapid development of China’s space industry,the mass and scale of the launch vehicle are increasing year by year,but the docking work of the domestic connector and the arrow interface is mainly artificial,and the rocket fuel is generally highly toxic or flammable and explosive,and the effect of wind load,the arrow interface will be shaken with the arrow body,not only will cause positioning error,but also produce a huge load on the connector.Therefore,the research on the automatic docking technology between the connector and the upper interface of the arrow is of great significance to improve the safety of personnel and solve the needs of rapid launch,and the development of a set of automatic docking equipment for the carrier rocket connector has become one of the important key technologies in the field.In this paper,according to the requirements of automatic docking of launch vehicle connector,combined with the characteristics of series and parallel mechanism,the concept of modularity is adopted to integrate macromotion attitude adjustment module and micro-motion attitude adjustment module reasonably and cooperate actively and passively.This paper proposes and designs a platform of nine degrees of freedom butt joint operation mechanism for side hanging follow-up tracking.In this paper,a deep and systematic basic research is carried out on the nine-degree of freedom platform of side-mounted tracking,which provides theoretical support for the engineering design of automatic docking equipment of launch vehicle connector.According to the technical objectives and requirements of the automatic connector docking process,a nine-degree of freedom hybrid coupling automatic docking mechanism and equipment scheme of launch vehicle connector is innovatively proposed and designed.The engineering structure design of the overall scheme of the hybrid platform is completed,and the three-dimensional model is established,wherein the macro motion adjustment mechanism completes the spatial three-degree-of-freedom translation,and the micro-motion adjustment completes the spatial six-degree-of-freedom micro-motion adjustment.The integrated hybrid platform can meet the required movement,and can withstand the load and impact during the docking process.The constraint equation is established based on the geometric characteristics of the mechanism,and the inverse solution is obtained based on the engineering conditions.Analytic method is used to solve the position-positive solution of the lateral tracking hybrid platform.By derivation of the inverse solution relation,the velocity and acceleration of the side-mounted tracking platform are analyzed,and the first-order and second-order influence coefficients of the hybrid platform are obtained.The linear velocity,angular velocity and acceleration formulas of the moving platform of each sub-mechanism are derived.Based on the analysis of the working space specified by each branch of the lateral tracking hybrid mechanism platform,the mathematical model is established.Considering the simple position inverse solution of the parallel mechanism and the influence of the rod length on the working space,MATLAB software was used for programming based on the position inverse solution algorithm to obtain the maximum length of the driving rod and complete the dimensional synthesis of the mechanism.According to the constraint conditions and position inverse solution,the working space of the hybrid platform is determined,and it is proved that the working space of the hybrid platform can meet the required range of motion.In order to ensure the safety and reliability of the drive and transmission during attitude adjustment,the statics characteristics of the key modules are studied,and the mechanical analysis,design calculation and selection of the drive branch chain of the twopart mechanism are carried out in detail.In order to ensure the strength and stiffness of the joint mechanism without resonance,finite element analysis and modal analysis were carried out on the side-mounted tracking hybrid platform.