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A New Spiral-Type Inflatable Pure Torsional Soft Actuator
Jihong Yan1,2, Xinbin Zhang2,3, Binbin Xu1
11 State Laboratory of Robotics and System, Harbin Institute of Technology , Harbin, China .
Soft Robotics
|July 6, 2018
Summary
Researchers developed a novel inflatable soft actuator with pure torsional motion, simplifying soft robot control and analysis. This new actuator achieves high torsion angles and output torque for effective manipulation tasks.
Area of Science:
- Robotics
- Materials Science
- Mechanical Engineering
Background:
- Soft robots offer advantages like deformability and impact resistance over rigid robots.
- Coupled deflections in soft materials complicate kinematic modeling, dynamic analysis, and control.
- Unwanted deformations can reduce efficiency and cause harmful environmental interactions.
Purpose of the Study:
- To introduce a novel inflatable soft actuator with pure torsional motion.
- To address challenges posed by coupled deformations in soft robotic systems.
- To enable simpler theoretical analysis and control for soft actuators.
Main Methods:
- Developed an inflatable soft actuator utilizing two spiral chambers twined with fibers.
- Established a kinematic model using the virtual work principle and elastic strain energy function.
- Experimentally investigated the kinematic properties and output torque of the fabricated actuator module.
Main Results:
- The actuator demonstrated pure torsional motion without bending or extension under no load.
- Exhibited good linearity with air pressure from 35 to 100 kPa.
- Achieved up to 110° torsion angle with ±2° accuracy and a maximum output torque of 0.026 N·m at 100 kPa.
Conclusions:
- The novel soft torsional actuator simplifies analysis and control by eliminating coupled deformations.
- Successfully assembled and demonstrated three soft robots performing manipulation tasks using the actuator.
- This work offers insights for designing linear soft actuators without coupled deformations.
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