Contrastive analysis of dynamics modelling and parameters identification for a flexible finger joint based on cable-driven series elastic actuator

Abstract

This paper presents a study on the dynamics modelling and parameters identification of a flexible finger joint, which is based on Cable-Driven Series Elastic Actuator (CDSEA). This kind of CDSEA includes of a pair of driving and returning cable modules, which provides the driving torque of a small finger joint. The driving cable is driven by a DC motor and miniature ballscrew, and the returning cable is back driven by a linear spring. The wirerope is simplified as mass-spring-damper system model, and considering the local dynamics characters and different inputting sensors data, six kinds of dynamic models are presented for the flexible finger joint in this study. Furthermore, the dynamic models are identified using the inverse dynamic identification model with least square method, and the contrastive analysis of the experimental results show that the raster displacement detection system can help to realize good performance and accuracy of parameters identification, and these six kinds of dynamic models can be furtherly used in the position control, external force estimation and force control of the flexible finger joint based on CDSEA.