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arXiv · 2109.04681

Jammkle: Fibre jamming 3D printed multi-material tendons and their application in a robotic ankle

James Brett·Katrina Lo Surdo·Lauren Hanson·Joshua Pinskier·David Howard
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Abstract

Fibre jamming is a relatively new and understudied soft robotic mechanism that has previously found success when used in stiffness-tuneable arms and fingers. However, to date researchers have not fully taken advantage of the freedom offered by contemporary fabrication techniques including multi-material 3D printing in the creation of fibre jamming structures. In this research, we present a novel, modular, multi-material, 3D printed, fibre jamming tendon unit for use in a stiffness-tuneable compliant robotic ankle, or Jammkle. We describe the design and fabrication of the Jammkle and highlight its advantages compared to examples from modern literature. We develop a multiphysics model of the tendon unit, showing good agreement with experimental data. Finally, we demonstrate a practical application by integrating multiple tendon units into a robotic ankle and perform extensive testing and characterisation. We show that the Jammkle outperforms comparative leg structures in terms of compliance, damping, and slip prevention.

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James Brett, Katrina Lo Surdo, Lauren Hanson, Joshua Pinskier, David Howard. 2021-09-10. Jammkle: Fibre jamming 3D printed multi-material tendons and their application in a robotic ankle. https://arxiv.org/abs/2109.04681

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