Continuum robots have high degrees of freedom and the ability to safely move in constrained environments. One class of soft continuum robot is the “vine” robot. This type of robot extends from its tip by everting or unfurling new material, driven by internal body pressure. Most vine robot examples store new body material in a reel at their base, passing it through the core of the robot to the tip, and like many continuum robots, steer by selectively lengthening or shortening one side of the body. While this approach to steering and material storage lends itself to a fully soft device, it has three key limitations: (i) internal friction of material passing through the core of the robot limits its length in tortuous paths, (ii) body buckling as the robot's body material is re-spooled at the base can prevent retraction, and (iii) constant curvature steering limits the robot's poses and object approach angles in a given workspace. This letter presents a hybrid soft-rigid robotic system comprising a soft vine robot body and a rigid, mobile, internal steering-reeling mechanism (SRM); this SRM is equipped with a reel for material storage, a bending actuator for steering, and is capable of actuating themore »
SPHR: A Soft Pneumatic Hybrid Robot with extreme shape changing and lifting abilities
Many soft robots are capable of significantly changing their shape, an ability that can offer advantages in many applications. For instance, such a robot can flatten its body to fit under small gaps and expand to move over large obstacles. Further, because these shape changes are usually driven by a pressurized fluid, if they act over a large area, they have the potential to apply large forces to the world. However, when these same shape changes are used for the locomotion of an untethered robot, they tend to result in slow forward movement. Here we present a hybrid soft-rigid elongated-sphere robot that decouples shape change from locomotion. Pairing a compliant, inflatable outer skin, which changes volume by 15x to both fit under and roll over obstacles and can lift objects up to 30 kg, with a wheeled internal carriage, we obtain relatively fast locomotion. A new two-sided controllable adhesive between the internal carriage and the skin enables the carriage to climb vertically inside the skin, allowing the robot to climb external obstacles. We present the design of the robot, simple modeling of its behavior, and experimental testing. Our work advances the area of hybrid soft-rigid robotics by demonstrating how leveraging more »
- Award ID(s):
- 1925373
- Publication Date:
- NSF-PAR ID:
- 10294799
- Journal Name:
- Proceedings of the IEEERSJ International Conference on Intelligent Robots and Systems
- ISSN:
- 2153-0858
- Sponsoring Org:
- National Science Foundation
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