Research on Input Scheme Selection of a Novel Parallel Mechanism

Abstract

When the two arms of the robot are transporting the heavy loads together, a new parallel mechanism is formed. The actuator input selection and optimization of the parallel mechanism are basic and important problems in mechanism research. In this paper, a 2-RPPPS dual-arm robot is taken as the research object. Firstly, based on the screw theory and input selection principle, 158 reasonable schemes are obtained. Then, an evaluation mechanism is established to screen out the schemes that do not conform to the input selection principle. Then, the end effector of the parallel mechanism moves along two different trajectories. Using the particle swarm optimization algorithm, the inverse kinematics solution of each trajectory is obtained, and the velocity and acceleration of each actuator under different trajectories are obtained. Finally, the motion stability of each actuator is evaluated, and the best scheme is selected. The results show that the best input scheme can be selected according to different trajectories, so as to improve the performance of the parallel mechanism. To the authors’ knowledge, no one has done any research on selecting the appropriate input scheme according to the trajectory of the end effector.

Sensitivity Analysis of Reliability of Low-Mobility Parallel Mechanisms Based on a Response Surface Method

“…Tian and Zhang Designed generalized parallel manipulators, and the position analysis of the GPM was carried out to evaluate the workspace and reveal the motion characteristics [26]. Chen et al researched the actuator input selection and optimization of the parallel mechanism, and evaluated the motion stability of each actuator [27]; Amir et al presented analytical approach for the dimensional synthesis of the 3-DOF Delta parallel robot for a prescribed workspace [28]. Li et al conducted research on the kinematics and error analysis considering the parallelism error of the mechanism [29].…”