Tendon Locking for Antagonistic Configuration- and Stiffness-Control in Soft Robots

authored by

Johann Licher, Jan Peters, Annika Raatz, Helge A. Wurdemann

Abstract

Some applications, such as surgical interventions, require that potential soft robots have the capability to alter their shape and enhance their force output on demand. This paper presents an antagonistic stiffening mechanism combining pneumatic actuation with tendon locking to achieve configuration- and stiffness control. Elongation of a soft pneumatic section, resulting from air actuation, is opposed by constraining the length of integrated tendons. These tendons can be locked in length by pneumatically activated levers at the base of each segment. Hence, tendon locking will not affect the configuration of other segments of a multi-segment manipulator. Our concept achieves a stiffness increase of up to 201.7% and a larger, more uniform radial workspace compared to the widely used pneumatic actuation concept while maintaining the low technical effort required for actuation. We also demonstrate how our actuation concept enables independent control of stiffness levels for individual segments of a multi-segment manipulator and their MR compatibility.

Organisation(s)

Institute for Assembly Technology and Robotics

External Organisation(s)

UCL

Type

Conference contribution

Pages

15322-15328

No. of pages

7

Publication date

13.05.2025

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Software, Control and Systems Engineering, Artificial Intelligence, Electrical and Electronic Engineering

Electronic version(s)

https://doi.org/10.1109/ICRA55743.2025.11127937 (Access: Closed)