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Published on: August 17, 2018
Spider-Inspired Electrohydraulic Actuators for Fast, Soft-Actuated Joints.
Nicholas Kellaris1,2, Philipp Rothemund1,3, Yi Zeng1
1Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, CO, 80309, USA.
Researchers developed novel spider-inspired electrohydraulic soft-actuated (SES) joints. These lightweight robotic joints offer fast, powerful, and efficient actuation, mimicking spider locomotion for advanced robotics.
Area of Science:
- Robotics
- Bio-inspired Engineering
- Soft Actuation
Background:
- Spider locomotion and manipulation inspire advanced robotic designs.
- Existing robotic actuation mechanisms face limitations in speed, force, displacement, and efficiency.
- Bio-inspired solutions are needed to overcome current actuation challenges.
Purpose of the Study:
- To develop novel soft-actuated joints inspired by spider leg hydraulics.
- To create lightweight, low-profile articulating mechanisms with enhanced performance.
- To demonstrate the versatility and applicability of these new joints in robotic systems.
Main Methods:
- Utilized electrostatic forces to pressurize hydraulic fluid within segmented structures.
- Developed spider-inspired electrohydraulic soft-actuated (SES) joints.
- Integrated SES joints to create complex robotic components like bidirectional joints and grippers.
Main Results:
- Demonstrated SES joints with large rotation angles (up to 70°) and high blocked torques (up to 70 mN·m).
- Achieved high specific torques (up to 21 N·m·kg⁻¹) and specific power (up to 230 W·kg⁻¹), comparable to human muscle.
- Showcased high-speed operation with roll-off frequencies up to 24 Hz.
Conclusions:
- SES joints represent a significant advancement in soft actuation for robotics.
- The lightweight, high-performance design is suitable for rapid maneuvering robotic systems.
- These joints offer a versatile platform for developing sophisticated articulating robots.
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