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We describe a new series pneumatic artificial muscle (sPAM) and its application as an actuator for a soft continuum robot. The robot consists of three sPAMs arranged radially around a tubular pneumatic backbone. Analogous to tendons, the sPAMs exert a tension force on the robot’s pneu- matic backbone, causing bending that is approximately constant curvature. Unlike a traditional tendon driven continuum robot, the robot is entirely soft and contains no hard components, making it safer for human interaction. Models of both the sPAM and soft continuum robot kinematics are presented and experimentally verified. We found a mean position accuracy of 5.5 cm for predicting the end-effector position of a 42 cm long robot with the kinematic model. Finally, closed-loop control is demonstrated using an eye-in-hand visual servo control law which provides a simple interface for operation by a human. The soft continuum robot with closed-loop control was found to have a step-response rise time and settling time of less than two seconds.
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This content will become publicly available on October 1, 2027
Design, Modeling, and Validation of an Extendable Tendon-Driven Robot for Long-Term Deployment in Congested and Evolving Outdoor Environments
Robotic systems for long-term monitoring in dense natural environments require a minimal physical footprint with the ability to maneuver through confined spaces, while being robust to harsh conditions. This work presents the design, modeling, and implementation of a compact, tendon driven continuum robot capable of controlled extension and spatial bending within a self-contained, protective actuation package. The system is comprised of a meter-long, single section, three-tendon “tendril” that deploys from a central reel mechanism. Integrated load cells provide tension sensing, and a tip camera supports control feedback and data collection. A Denavit-Hartenberg-based kinematic model is adapted to enable motion planning for the variable-length continuum section. To compensate for modeling inaccuracies arising from the inherent compliance of the flexible tendril, a closed-form tension distribution model is introduced to support feedback based refinement of the robot pose. The robot prototype demonstrated navigating cluttered natural environments and was deployed outdoors over a total of five months,
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- Award ID(s):
- 2506466
- PAR ID:
- 10696908
- Publisher / Repository:
- IEEE
- Date Published:
- Format(s):
- Medium: X
- Location:
- Pittsburgh, PA
- Sponsoring Org:
- National Science Foundation
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