A novel acceleration capacity index based on motion/force transmissibility for high-speed parallel robots. (August 2018)

• Record Type: Journal Article
• Authors: Liu, Xin-Jun; Han, Gang; Xie, Fugui; Meng, Qizhi
• Is Part Of: Mechanism and machine theory. Volume 126(2018)
• Page Start: 155
• Page End: 170
• Publication Date: 2018-08
• Subjects: Dynamic performance evaluation -- High-speed parallel robot -- Acceleration capacity index -- Power transmissibility; Machine theory -- Periodicals; Machinery -- Periodicals; Machines -- Périodiques; Génie mécanique -- Périodiques; Machine theory; Machinery; Periodicals; 621.81
• DOI: 10.1016/j.mechmachtheory.2018.03.013
• Languages: English
• ISSNs: 0094-114X

Abstract

Highlights: Definition of the Acceleration Capability index as the worst case normalized torque for predefined maximum translational and rotational accelerations. The comprehensive interaction mechanism of motion/force transmissibility to parallel robots' acceleration capacity is studied and presented in the proposed index. Through matching the motors and gearboxes with the parallel mechanism, the index can give an accurate evaluation of the whole robot's acceleration capacity. This index can also measure the closeness to the singularities. This index is applied to a 4-DOF high-speed parallel robot for acceleration capacity measurement and suitable workspace identification. Abstract: Dynamic performance evaluation is an open question considering three main challenging issues: (a) how to avoid performance indices physically inconsistent considering different dimensions of translational and rotational performance of parallel robots; (b) how to accurately evaluate the performance of the whole robots considering different capacity of driving motors, active arms and moving platforms; (c) how to understand the inner relationship between the dynamic performance and parameters of robots. In this paper, through matching the driving system with the parallel mechanism, an acceleration capacity index of the whole robot is proposed for high-speed parallel robots with mixed types of DOFs (translations and rotations). From the view of power transmissibility, the comprehensive interaction mechanism of motion/force transmissibility to the acceleration capacity of the robot is analyzed and presented in the proposed index. Thus, the index can measure the acceleration capacity accurately. For validation purpose, this index is applied to acceleration capacity evaluation of a high-speed parallel robot, identifying a suitable workspace to reduce the driving torque. This index is general and can be further applied to parameters optimization for different types of high-speed parallel robots.