Inverse rigid-body dynamic analysis for a 3UPS-PRU parallel robot

Yongjie Zhao,Gang Cheng,Ziqiang Zhang

doi:10.1177/1687814017693194

Abstract

Inverse rigid-body dynamic analysis for a 3UPS-PRU parallel robot are conducted in this research. The position, velocity, acceleration, jerk, and singularity are considered in the inverse kinematics analysis. The rigid-body dynamic model is developed by means of the principle of virtual work and the concept of link Jacobian matrices. The driving torque, driving power, and required output work of motors have been computed in the inverse rigid-body dynamics analysis. For the pre-defined trajectory, the required output work generated by the driving motor is achieved by numerical integration technique. The inverse kinematics and rigid-body dynamics have been investigated in an exhaustive decoupled way. The effects of the velocity of the moving platform on the components of the joint acceleration, joint jerk, driving torque, and driving power, which are related to the velocity of the moving platform, are investigated. There are linear relationships between the acceleration of the moving platform and the components of the joint acceleration, joint jerk, driving torque, and driving power, which are related to the acceleration of the moving platform. The total driving torques, the torques related to the acceleration, velocity, and gravity, the torques related to the moving platform, strut connected with the moving platform, strut connected with the base platform, and motor rotor-coupler are calculated. The total driving powers, the powers related to the acceleration component of torque, velocity component of torque, gravity component of torque, and the powers related to the moving platform, strut connected with the moving platform, strut connected with the base platform, and motor rotor-coupler are also achieved.

Highlights

Parallel robots have been widely used in motion simulators,[1,2,3] high-speed operations,[4,5,6] machine tools,[7,8,9] and so on
The goal of the research presented in this article is to develop the analytic models for inverse kinematics and rigid-body dynamics of a 3UPS-PRU parallel robot considering the position, velocity, singularity, acceleration, jerk, driving torque, driving power, and energy consumption
From equations (45), (50), (53), (55), (60), (88), and (91), there are linear relationships between the acceleration of the moving platform and the components of the joint acceleration, joint jerk, driving torque, and driving power, which are related to the acceleration of the moving platform

Summary

Introduction

Parallel robots have been widely used in motion simulators,[1,2,3] high-speed operations,[4,5,6] machine tools,[7,8,9] and so on. The existing work on the inverse kinematics and rigid-body dynamics of the parallel robots seldom considers the decoupling of the rigid-body dynamic model and the effects of the velocity and acceleration of the moving platform on the acceleration, jerk, driving torque, and driving power of the actuating joints. The goal of the research presented in this article is to develop the analytic models for inverse kinematics and rigid-body dynamics of a 3UPS-PRU parallel robot considering the position, velocity, singularity, acceleration, jerk, driving torque, driving power, and energy consumption. Taking the derivative of left side of equation (7) with respect to time, we get the velocity of the point of the joint Ai vAi = q_ 0w0 + v 3 ai = v + v 3 ai ð21Þ where v is the linear velocity vector of the moving platform, and v = q_ 0w0 = vw[0].

Bi wiy ÀBi wix 5

Conclusion