Design And Analysis Of Five-branch Five-degree-of-freedom Attitude Adjustment Parallel Platform

Robots are indispensable equipment in the production of modern society,and parallel robots have received more and more attention and application due to their large rigidity,high carrying capacity,fast response speed,easy control and many other outstanding advantages.This paper designs a three-shift,two-turn five-degree-of-freedom pose adjustment parallel platform installed at the end of the gantry robot to improve the working accuracy.The posture adjustment parallel platform can also be used in modern industrial production and other five-degree-of-freedom workplaces.Firstly,a parallel mechanism with three shifts and two revolutions is proposed as a prototype mechanism for posture adjustment parallel platform.The spiral theory and ADAMS were used to analyze and verify the degree of freedom for regulating the parallel platform.The position solution of the adjustable parallel platform was analyzed,and the spatial boundary search method was used to solve and draw the position and attitude working space of the mechanism.The speed transfer performance and bearing capacity performance of the parallel platform are solved,the influence of size parameters on the speed transfer performance index,bearing capacity performance evaluation index and working space are analyzed,and a set of mechanism size parameters are selected based on this index.The Jacobian matrix of velocity and acceleration of the adjustable parallel platform was solved,the Newton-Euler method was used to establish the dynamic equation system of each member of the adjustable parallel platform,the dynamic equation system of the whole machine of the regulated parallel platform was established by the Lagrange method,the virtual prototype of the adjustable parallel platform was designed,and the dynamic simulation was carried out in combination with ADAMS,and the simulation verified the correctness of the establishment of the dynamic model.The closed-loop vector equation of the motion branch of the parallel platform with pose adjustment is established,and the influence degree of each motion member forming the motion branch chain on the output error is obtained through the differential operation of the vector equation.The mechanism error model is constructed based on the forward and reverse solution of kinematics,and the correctness of the error model establishment is verified by simulation.Finally,the output pose error of the parallel platform of pose adjustment is compensated according to the spatial compensation method,so that the compensated output pose error meets the requirements,and the feasibility of this method is verified by simulation.