Journal of Bionic Engineering ›› 2022, Vol. 19 ›› Issue (6): 1699-1711.doi: 10.1007/s42235-022-00222-z

• • 上一篇    下一篇

Modeling and Analysis of Soft Bionic Fingers for Contact State Estimation

Yongyao Li1; Ming Cong1; Dong Liu1; Yu Du2   

  1. 1 School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China  2 School of Mechanical Engineering, Dalian Jiaotong University, Dalian 116028, China
  • 收稿日期:2022-01-06 修回日期:2022-05-15 接受日期:2022-05-18 出版日期:2022-11-10 发布日期:2022-11-10
  • 通讯作者: Yu Du E-mail:duyu@djtu.edu.cn
  • 作者简介:Yongyao Li1; Ming Cong1; Dong Liu1; Yu Du2

Modeling and Analysis of Soft Bionic Fingers for Contact State Estimation

Yongyao Li1; Ming Cong1; Dong Liu1; Yu Du2   

  1. 1 School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China  2 School of Mechanical Engineering, Dalian Jiaotong University, Dalian 116028, China
  • Received:2022-01-06 Revised:2022-05-15 Accepted:2022-05-18 Online:2022-11-10 Published:2022-11-10
  • Contact: Yu Du E-mail:duyu@djtu.edu.cn
  • About author:Yongyao Li1; Ming Cong1; Dong Liu1; Yu Du2

摘要: Contact state estimation is significant for evaluating grasp stability of bionic hands, especially in unknown environments or without visual/tactile feedback. It still remains challenging, particularly for soft bionic hands without integrating complicated external sensors on soft fingers. Focusing on this issue, a proprioceptive-sensing-based systematic solution is proposed to estimate the contact state of soft bionic fingers in a single grasp. A kinematic model for soft fingers is first developed to capture the joint rotation angles and tendon displacement. A kinetostatic model is further built to estimate the contact force when soft fingers come in contact with objects. On this basis, a system stiffness model for soft fingers during preshaping and initial contact with objects is proposed to perceive the contact state. Moreover, an instantaneous stiffness model for soft fingers when initial contact occurs is developed for estimating the contact position on certain phalanges, especially the contact position along the distal phalange. The proposed proprioceptive-sensing-based approach is the first application in soft fingers without integrating complicated external sensors, which makes them concise and practical. Experiments are carried out to demonstrate the effectiveness and efficiency of our proposal.

关键词: Proprioceptive-sensing-based modeling , · Soft bionic hand , · Contact state estimation , · Stiffness analysis

Abstract: Contact state estimation is significant for evaluating grasp stability of bionic hands, especially in unknown environments or without visual/tactile feedback. It still remains challenging, particularly for soft bionic hands without integrating complicated external sensors on soft fingers. Focusing on this issue, a proprioceptive-sensing-based systematic solution is proposed to estimate the contact state of soft bionic fingers in a single grasp. A kinematic model for soft fingers is first developed to capture the joint rotation angles and tendon displacement. A kinetostatic model is further built to estimate the contact force when soft fingers come in contact with objects. On this basis, a system stiffness model for soft fingers during preshaping and initial contact with objects is proposed to perceive the contact state. Moreover, an instantaneous stiffness model for soft fingers when initial contact occurs is developed for estimating the contact position on certain phalanges, especially the contact position along the distal phalange. The proposed proprioceptive-sensing-based approach is the first application in soft fingers without integrating complicated external sensors, which makes them concise and practical. Experiments are carried out to demonstrate the effectiveness and efficiency of our proposal.

Key words: Proprioceptive-sensing-based modeling , · Soft bionic hand , · Contact state estimation , · Stiffness analysis