Dynamic Locomotion Article 2022

A Novel Spider-Inspired Rotary-Rolling Diaphragm Actuator with Linear Torque Characteristic and High Mechanical Efficiency

Images large soro.2020.0108 figure2

We present a novel, fluid-driven rotary-rolling diaphragm actuator with direct rotary output. Its working principle is inspired by the spider leg's hydraulically operated joints and the diaphragm design of rolling diaphragm actuators. The new actuator is fully sealed, shows minimal output torque losses, and minimum friction during operation. Stiction and Coulomb friction are avoided by design. Our proposed mechanism can be used as a compliant actuator in soft robots, or as a stiff transmission device, depending on the fluid and working pressure. The rotary-rolling diaphragm is the defining component of the actuator. The diaphragm is based on silicone rubber, reinforced by a fabric with anisotropic tensile strength characteristics. The diaphragm is custom-designed to follow the actuator's toroidal shape and to ensure the smooth unrolling behavior throughout the stroke. Our actuator outputs a constant torque throughout its stroke compared with monolithic, rotary soft robot actuators with a change in torque. Our design offers a high mechanical efficiency of 95\%, compactness, a wide working range of 100°, and a low mechanical complexity from a single chamber.

Author(s): Jonas Hepp and Alexander Badri-Spröwitz
Journal: Soft Robotics
Volume: 9
Number (issue): 2
Pages: 364--375
Year: 2022
Month: April
Day: 19
Publisher: Mary Ann Liebert, Inc.
Bibtex Type: Article (article)
DOI: 10.1089/soro.2020.0108
State: Published
URL: https://www.liebertpub.com/doi/10.1089/soro.2020.0108
Digital: True
Electronic Archiving: grant_archive
Links:

BibTex

@article{hepp2021,
  title = {A Novel Spider-Inspired Rotary-Rolling Diaphragm Actuator with Linear Torque Characteristic and High Mechanical Efficiency},
  journal = {Soft Robotics},
  abstract = {We present a novel, fluid-driven rotary-rolling diaphragm actuator with direct rotary output. Its working principle is inspired by the spider leg's hydraulically operated joints and the diaphragm design of rolling diaphragm actuators. The new actuator is fully sealed, shows minimal output torque losses, and minimum friction during operation. Stiction and Coulomb friction are avoided by design. Our proposed mechanism can be used as a compliant actuator in soft robots, or as a stiff transmission device, depending on the fluid and working pressure. The rotary-rolling diaphragm is the defining component of the actuator. The diaphragm is based on silicone rubber, reinforced by a fabric with anisotropic tensile strength characteristics. The diaphragm is custom-designed to follow the actuator's toroidal shape and to ensure the smooth unrolling behavior throughout the stroke. Our actuator outputs a constant torque throughout its stroke compared with monolithic, rotary soft robot actuators with a change in torque. Our design offers a high mechanical efficiency of 95\%, compactness, a wide working range of 100°, and a low mechanical complexity from a single chamber.},
  volume = {9},
  number = {2},
  pages = {364--375},
  publisher = {Mary Ann Liebert, Inc.},
  month = apr,
  year = {2022},
  slug = {hepp2021},
  author = {Hepp, Jonas and Badri-Spr{\"o}witz, Alexander},
  url = {https://www.liebertpub.com/doi/10.1089/soro.2020.0108},
  month_numeric = {4}
}