Stable grip control on soft objects with time-varying stiffness
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Humans can hold a live animal like a hamster without overly squeezing despite the fact that its soft body undergoes impedance and size variations due to breathing and wiggling. Although the exact nature of such biological motor controllers is not known, existing literature suggests that they maintain metastable interactions with dynamic objects based on prediction rather than reaction. Most robotic gripper controllers find such tasks very challenging mainly due to hard constraints imposed on the stability of closed-loop control and inadequate rates of convergence of adaptive controller parameters. This paper presents experimental and numerical simulation results of a control law based on a relaxed stability criterion of reducing the probability of failure to maintain a stable grip on a soft object that undergoes temporal variations in its internal impedance. The proposed controller uses only three parameters to interpret the probability of failure estimated using a history of grip forces to adjust the grip on the dynamic object. Here, we demonstrate that the proposed controller can maintain smooth and stable grip tightening and relaxing when the object undergoes random impedance variations, compared with a reactive controller that involves a similar number of controller parameters.
Date Issued
2016-06-01
Date Acceptance
2016-03-24
Citation
IEEE Transactions on Robotics, 2016, 32 (3), pp.626-637
ISSN
1552-3098
Publisher
Institute of Electrical and Electronics Engineers
Start Page
626
End Page
637
Journal / Book Title
IEEE Transactions on Robotics
Volume
32
Issue
3
Copyright Statement
© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Identifier
https://ieeexplore.ieee.org/document/7471513
Subjects
Science & Technology
Technology
Robotics
Reduction of probability of failure
stable grip control
variable stiffness objects
IMPEDANCE CONTROL
IDENTIFICATION
UNCERTAINTY
FORCE
Industrial Engineering & Automation
0801 Artificial Intelligence and Image Processing
0906 Electrical and Electronic Engineering
0913 Mechanical Engineering
Publication Status
Published
Date Publish Online
2016-05-18