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arXiv · 2609.23132

Tip Manipulation in Soft Everting Robots via Wall Retraction and Deployable Fingers

Abstract

Soft everting robots can traverse long, confined paths by continuously growing, yet active interaction remains limited to a single tool fixed at or near the tip, unable to be repositioned on demand and difficult to reconcile with the robot's soft body. We introduce a tip-manipulation and multi-tool deployment strategy for soft everting robots based on wall retraction, implemented with a base roller assembly that independently meters membrane flow in the outer wall while a tail spool regulates growth in the internal tail section. Coordinated wall and tail actuation decouples robot length from membrane-material position, enabling membrane-mounted devices to be transported, exposed, and repositioned at selected locations near the distal tip. We pair this capability with ultralight pleated inflatable fingers integrated into the membrane, fabricated from TPU-coated nylon with an internal airtight bladder. The fingers achieve large bending at low pressures (approximately 100 degrees at 50 kPa in high-pleat designs) and generate blocking forces up to 1.9 N, while remaining limp during transport. The system demonstrates adaptive grasping across diverse household objects (21 to 550 g; 16 to 200 mm), three-dimensional object manipulation and stacking, environmentally braced extension, distal camera panning for confined-space inspection, and controlled sequential payload delivery. These results enable embodied and reversible tip manipulation for soft growing robots in cluttered and tortuous environments.

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BibTeXRIS

Nelson Badillo Perez, Niccolo Pagliarani, Matteo Cianchetti, Robert D. Howe. 2026-09-19. Tip Manipulation in Soft Everting Robots via Wall Retraction and Deployable Fingers. https://arxiv.org/abs/2609.23132

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