Force Principle And Test Research Of Redundant Parallel Mechanism Under Different Control Modes

Redundant drive parallel mechanism is a kind of over-constrained parallel mechanism whose number of actuators is greater than the degree of freedom of mechanism.It plays an obvious role in avoiding singular configuration,increasing workspace,increasing stiffness and increasing load-carrying capacity,and has a broad application prospect.This paper will take 2SPS-P redundant drive parallel mechanism as an example to analyze the force principle and coordinated control strategy of redundant drive parallel mechanism under three different control modes.The main research contents include:Firstly,the force principle of 2SPS-P redundant drive parallel mechanism under three modes of full position control,full control and force/position hybrid control is analyzed,and the influence of branch stiffness on branch output(or input)displacement,drive force distribution and output motion accuracy of moving platform under different control modes is clarified.The research results on redundant drive parallel mechanism design and control are also presented.The system and use have very important reference significance.Secondly,the prototype of 2SPS-P redundant drive parallel mechanism is designed in detail,and the traditional single-rail moving pair is optimized.The selection methods and parameters of power components(electric cylinder)and detection components(force sensor)of the equipment are introduced,and the ANSYS finite element analysis of the whole frame of the mechanism is carried out.Thirdly,the hardware system,electrical system and control programming program of the control system are analyzed systematically.The framework of the overall control structure of the control system and the communication circuit of the force sensor are designed.The signal transmission circuit between the controller and the driver,the communication circuit between the force sensor and the controller,the control parameters of the whole control system and the properties of the four control variables are described in detail.The PID parameters of the control system are carefully analyzed and the specific setting values are given.The acquisition system of cascade servo control loop and controller is set,and all acquisition addresses are set.Finally,a test platform of 2SPS-P redundant drive parallel mechanism is built,and its movement and force principle under three control modes are experimentally studied,and the theoretical analysis results are compared and analyzed to verify the correctness of the theoretical analysis.