Research On The Configuration And Control Strategy Of Three Degree Of Freedom Redundant Parallel Mechanism

With the development of science and technology,mobile radars are playing an increasingly important role in modern warfare.Compared with traditional fixed radars,high maneuvering vehicle radars have remarkable advantages,such as high mobility,high position adaptability,high concealment and high survivability.In order to meet the requirements of high precision,high automation and high reliability for the on-the-spot docking of the on-board radar antenna system,an automatic position and posture adjustment and docking system for heavy haul and large travel space posture is needed to facilitate transportation.In this paper,a three degree of freedom redundant parallel mechanism which can be conveniently installed on a transport vehicle is proposd,it can be used to adjust the degree of freedom along the vertical axis and the degree of freedom that rotate around the horizontal two axis.Compared with the traditional non-redundant parallel mechanisms,the existence of the redundant actuated branch of the redundant mechanism can not only improve the bearing capacity and stiffness of the mechanism,but also overcome the singularity of the mechanism itself.When part of the branched chain of the redundant parallel mechanism is damaged or damaged,the mechanism can still maintain a certain load capacity.Redundant parallel mechanism fully combines the characteristics of high bearing capacity,high positioning precision of parallel mechanism and the advantages of redundant mechanism to overcome its singularity and improve security.At the same time,a full active force position hybrid control strategy is proposed in this paper to solve the problem that redundant parallel mechanism produces great internal stress during the movement process.This control algorithm effectively solves the kinematic coupling problem of redundant parallel mechanisms,and effectively controls the internal stress of the mechanism.First,the overall design of the three degree of freedom redundant parallel mechanism is designed according to the design target.Fully combining the advantages of parallel mechanism and redundant drive mechanism,this paper designs a three degree of freedom redundant parallel mechanism satisfying the vehicle installation and transportation adjustment,and analyzes and demonstrates the mechanism configuration of the mechanism.Secondly,this paper carries out further kinematic positive solution and inverse kinematics calculation to provide control basis for the position feedback control link of the system.Through simulation calculation,the working space of the mechanism is worked out,and whether the workspace of the mechanism meets the design requirements is verified.The static and dynamic analysis of the mechanism is carried out in this paper.A simplified calculation method of driving force is provided to provide the control basis for the force feedback control link in the control of the mechanism.Thirdly,in order to solve the internal force problem caused by the movement of redundant actuators,a full active force position hybrid control algorithm is proposed to control the redundant actuation mechanism,so that the mechanism can automatically adjust itself to satisfy the strong coupling relationship of motion in real time.At the same time,ADAMS and MATLAB/Simulink are used for joint simulation analysis to verify the correctness of the control strategy.Finally,based on the mechanism and control strategy studied in this paper,an experimental system is built to verify the mechanism configuration and control strategy.The experimental results show that the proposed three degree of freedom redundant parallel structure has good spatial adjustment performance,and the proposed full active force position hybrid control algorithm has achieved good control effect.