New nonlinear stiffness actuator with predefined torque-deflection profile

Ju, Wenjie1; Gong, Hexi1; Qi, Keke1; Kang, Rongjie1; Dai, Jian S.1,2,3; Song, Zhibin1

2023

10.1007/s11465-022-0721-3

FRONTIERS OF MECHANICAL ENGINEERING   Impact Factor & Quartile

2095-0233

2095-0241

A nonlinear stiffness actuator (NSA) could achieve high torque/force resolution in low stiffness range and high bandwidth in high stiffness range, both of which are beneficial for physical interaction between a robot and the environment. Currently, most of NSAs are complex and hardly used for engineering. In this paper, oriented to engineering applications, a new simple NSA was proposed, mainly including leaf springs and especially designed cams, which could perform a predefined relationship between torque and deflection. The new NSA has a compact structure, and it is lightweight, both of which are also beneficial for its practical application. An analytical methodology that maps the predefined relationship between torque and deflection to the profile of the cam was developed. The optimal parameters of the structure were given by analyzing the weight of the NSA and the mechanic characteristic of the leaf spring. Though sliding friction force is inevitable because no rollers were used in the cam-based mechanism, the sliding displacement between the cam and the leaf spring is very small, and consumption of sliding friction force is very low. Simulations of different torque-deflection profiles were carried out to verify the accuracy and applicability of performing predefined torque-deflection profiles. Three kinds of prototype experiments, including verification experiment of the predefined torque-deflection profile, torque tracking experiment, and position tracking experiment under different loads, were conducted. The results prove the accuracy of performing the predefined torque-deflection profile, the tracking performance, and the interactive performance of the new NSA.

compliant actuator nonlinear stiffness actuator nonlinear spring predefined torque-deflection profile

SCI

English

Others

National Key R&D Program of China[2019YFB1312404] ; National Natural Science Foundation of China["51975401","51875393"]

Engineering

Engineering, Mechanical

WOS:000950732900001

HIGHER EDUCATION PRESS

Web of Science

1.Tianjin Univ, Sch Mech Engn, Tianjin 300350, Peoples R China
2.Southern Univ Sci & Technol, Coll Engn, Dept Mech & Energy Engn, Shenzhen 518055, Peoples R China
3.Univ London, Kings Coll London, London WC2R 2LS, England

Ju, Wenjie,Gong, Hexi,Qi, Keke,et al. New nonlinear stiffness actuator with predefined torque-deflection profile[J]. FRONTIERS OF MECHANICAL ENGINEERING,2023,18(1).

Ju, Wenjie,Gong, Hexi,Qi, Keke,Kang, Rongjie,Dai, Jian S.,&Song, Zhibin.(2023).New nonlinear stiffness actuator with predefined torque-deflection profile.FRONTIERS OF MECHANICAL ENGINEERING,18(1).

Ju, Wenjie,et al."New nonlinear stiffness actuator with predefined torque-deflection profile".FRONTIERS OF MECHANICAL ENGINEERING 18.1(2023).