Free Tendons for Travelling Wave Generation in Elastomer Membranes

Research output: Chapter in Book/Report/Conference proceedingConference Contribution (Conference Proceeding)

4 Downloads (Pure)


A novel method for the generation of travelling waves in soft robots is presented. Here a soft elastomer mem-brane is embedded with freely sliding nylon tendons. Instead of being anchored to a point on the membrane, these tendons transmit force via friction generated by sliding within the interior of the membrane. This system can produce continuous travelling waves with amplitudes of 27-45mm at wave speeds of up to 23mm/s, using only a single actuator to apply tension to the tendons. The travelling waves were able to move granular material (poppy seeds) as well as a 147g apple. Experimental results demonstrate that the wave progresses through three phases; the initial static phase, followed by the travelling wave phase and finally the (end of travel) blocked phase, with curvature increasing and wave amplitude decreasing across the travelling and blocked phases. This represents wave degradation in which the membrane compresses relative to the tendon, though this did not limit wave travel over the displacements tested. The wave speeds produced were an order of magnitude higher than tendon winding speed suggesting the system acts with natural gearing. This mechanism shows promise for applications in matter transport of unstructured or soft objects and the principle could also be applied to locomoting robots as the low amount of actuators and degrees of control would reduce the complexity and bulkiness of the robots.
Original languageEnglish
Title of host publication2021 IEEE 4th International Conference on Soft Robotics, RoboSoft 2021
Subtitle of host publication4th IEEE International Conference on Soft Robotics
Number of pages6
ISBN (Electronic)9781728177137
Publication statusPublished - 12 Jul 2021
EventRobosoft 2021: IEEE International Conference on Soft Robotics -
Duration: 12 Apr 202116 Apr 2021

Publication series

Name2021 IEEE 4th International Conference on Soft Robotics, RoboSoft 2021


ConferenceRobosoft 2021

Bibliographical note

Funding Information:
This work was partially funded by EPSRC grants EP/L015293/1 and EP/R02961X/1.

Publisher Copyright:
© 2021 IEEE.


  • Robotics
  • Soft robot
  • Travelling Waves


Dive into the research topics of 'Free Tendons for Travelling Wave Generation in Elastomer Membranes'. Together they form a unique fingerprint.

Cite this