Research On Motion Control For A 2-dof Parallel Robot

2-degree of freedom (2-DOF) parallel robots are one of the research branches of parallel robots. Many efforts have been made on their kinematics, dynamics, singularity, and workspace analysis, as well as their motion control. In this paper, a new parallel robotic mechanism with 2-DOF is designed, and deep research works are made on its mechanism structure and motion control.First, the mechanism stucture of the 2-DOF parallel robotic is designed. A parallelogram structure is used to constraint the rotation, so that the end of the 2-DOF parallel robot is kept to be horizontal. Four topics are analysed in detail, they are the forward and inverse kinematics, the input and output speed relationships, the work space of the 2-DOF parallel mechanism, and the theoretical principle of trajectory planning for the 2-DOF parallel robot.In order to achieve the 2-DOF parallel robot motion control, both the hardware and the software of the control system are designed. A print circuit board (PCB)-based adapter is designed to connect the DSP2812 motion control card and the Yaskawa servo drive unit. The adapter transfers the signals, pulse, analog voltage signals from the motion control card to the servo drive unit to control the motors operation. The programes of the software are also developed, which include the programe of human machine interface, pulse width module (PWM) wave, digtal and analog (D/A) process, the motor M/T control algorithm procedures.Finally, The motion control experiments are carried out according to the straight line and circle trajectory planning. The data are collected from the experiments and imported to the MatLab to conduct a simulation. The simulation results show that the trajectory is roughly the same as the default path. A conclusion can be drawn that the motion control of the 2-DOF parallel robot is achieved.