SIPHON: An Origami Soft Salp Robot
Brian Van Stratum, Nathan Justus, Ross Hatton, Joseph Davidson, Geoffrey Hollinger
AI summary
Problem
Existing pulsed-jet swimmers often rely on complex mechanisms, bidirectional flow, or surface swimming, which limits efficiency and restricts operational depth. There is a need for a simple, power-autonomous design that leverages unidirectional flow for better hydrodynamic performance.
Approach
SIPHON utilizes an interlocking Kresling origami bellows and passive duckbill/heart-inspired valves to intake and expel water unidirectionally with a single degree of freedom. The team derived a coupled Euler-Lagrange dynamic model and validated it against free-swimming pool trials.
Key results
- Mean swimming speed of 16.5 cm/s (0.59 BL/s)
- Cost of transport of 4.9 J/m (1.8 W·s/N·m)
- Experimental validation of a coupled dynamic model
- Untethered submerged swimming via passive valving
Why it matters
Offers a scalable, low-complexity blueprint for efficient soft robotic swimmers, advancing untethered marine exploration and multi-agent fluid dynamics research.
Abstract
We present SIPHON, a Salp-Inspired robot designed to utilize Passive Hydrodynamics, and equipped with soft robotic Origami bellows and soft Nozzles. We reveal the construction, including a novel use of an interlocking origami Kresling pattern, along with duckbill and mammal-heart-inspired valves. We derive a physical model for the coupled dynamics of body displacement and body contraction. We show experimental results of pool free swimming trials, and we compare these results to the model. Compared to other power-autonomous, bio-inspired pulsed jet swimmers, SIPHON swims with high speed and efficiency, achieving a mean swimming speed of 16.5 cm/s (0.59 Bl/s) and a cost of transport of 4.9 J/m (1.8 W s/(N m)).