Characteristic Analysis of a Variable Stiffness Actuator Based on a Rocker-Linked Epicyclic Gear Train

Abstract

This paper presents the characteristic analysis and mechanical realization of a novel variable stiffness actuator based on a rocker-linked epicyclic gear train (REGT-VSA). The stiffness adjustment of the actuator works by converting the differential motion of the planetary gear train into the linear motion of the elastic element. The unique design of the rocker-linked epicyclic gear train ensures excellent compactness and easy controllability, which enables the actuator to be qualified for constructing a manipulator toward cooperation applications. However, the output position and stiffness of the actuator may be affected by the mechanism clearance. The paper introduces characteristic analysis of stiffness and clearance, and carries out a series of related simulations. The analysis results can provide guidelines for the high-quality assembly of lever-based VSA.