Analysis Of Mechanism Characteristics And Research On Dynamical Characteristic Of The4-DOF High-speed Parallel Robot

The four DOF parallel robots are mainly used for carrying and automated sorting the electronics, food,medicine and so on. They can improve production efficiency and reduce the human resources and also can improve the quality of the production for their superiority. Therefore, it is important to research and develop the four DOF parallel robots for promoting our country’s industrial production lines.The research about four DOF parallel robots in domestic and foreign has been analysed in this paper, and taking four DOF parallel robots as the research object, the4-R (2-SS)-type parallel mechanism has been analysed, The mechanical structure of the four DOF high-speed parallel robot have been introduced. The design scheme of vacuum adsorption system and the of the choice of the various kinds of vacuum components have been completed.In order to solve the computational complexity of parallel mechanism’s degree of freedom, the screw theory has been used for the4-R (2-SS)-type parallel mechanism in this paper. Using this method, not only can calculate the number of degrees of freedom of the4-R (2-SS)-type parallel mechanism, but also can obtain the distribution of the degrees of freedom. The mathematical model of the robot has been built on account of the robot’s structure and its parameters. Taking the the rotation angle of drive, the range of ball-joint, coupling degree and the posture of end effector as constraint conditions, the dextrous workspace of four DOF high-speed parallel robot is searched using numerical method.Then, based on the mathematical model of four DOF high-speed parallel robots, the kinematic model of the robot is built, and the robot Jacobian matrix has been deduced by time derivative, all of these are the foundation for the analysis of the velocity and acceleration. And the dynamic model of the robot is built on the basis of the robot Jacobian matrix, which is the robot’s theoretical foundation.Finally, a virtual model has been built in ADAMS on the basis of mechanism parameters, in order to simulate the robot when the end effector moves along pick-place spline. The motion simulation show that the high-speed parallel robot has very good performances in kinematics performance. The robot has been assembled and the control system debugged. And the tested results show that the four DOF high-speed parallel robot can meet the practical requirement of carrying and sorting the products.