Research on path planning of parallel gangue selection robot

Abstract

At present, the coal gangue selection manipulator is mostly used in series. Compared with the series manipulator, the parallel manipulator can achieve higher movement speed in a short time, and the load capacity is stronger. Therefore, it is more suitable for the selection of heavy coal gangue. Taking the parallel gangue selection robot as the research object, the two dynamic sorting path planning methods of 'ladder' path planning and 'V' path planning of parallel manipulator are compared and analyzed. 'Ladder' path planning: after the end effector of the manipulator pushes the gangue out of the conveyor belt, it first lifts up a certain distance, and then completes the return movement. 'V' path planning: after the end effector of the manipulator pushes the gangue out of the conveyor belt, it first returns to the standard line, and then quickly moves to the position parallel to the next target gangue, completing one movement cycle. By establishing the mechanical model of the parallel manipulator, the torque variation of the drive motor is explored when the manipulator moved along the two paths. The time for completing a movement cycle along the two paths is calculated on the premise that the torque met the requirements. And the working efficiency of the manipulator along the two paths is compared. The simulation results show that the time taken to complete a movement cycle along 'ladder' path and 'V' path is 1.2, 0.65 s respectively. The 'V' path takes a shorter time and has a higher gangue selection efficiency. The site application results show that the average gangue selection rate is 94.23% and 88.28% respectively when the 'V' path and the 'ladder' path are adopted. The total time of the 'V' path is nearly 19% less than that of the 'ladder' path, and the gangue selection efficiency is higher.

Keywords

• gangue selection robot
• parallel manipulator
• end effector
• path planning
• 'ladder' path
• 'v' path