Marine Engineer Mimics Oarfish Fin to Create Quiet Deep‑Sea Vehicle

Rob Shepherd, an expert in marine robotics, unveiled a novel design for a sizable submersible that copies the ribbon‑shaped dorsal fin of the rare oarfish. Intended to deliver almost silent thrust, the concept may let scientists get close to delicate marine organisms without perturbing them.

Spanning several meters, the oarfish moves by producing traveling waves along its long dorsal fin. In contrast to most fish that depend on tail or pectoral fin power, this motion produces a gentle, low‑frequency undulation that drives the animal forward while emitting very little sound. Shepherd’s group analyzed high‑speed footage of the creature in the wild to capture the precise kinematics of the fin’s wave motion.

Using those observations, the constructed robot features a pliable, segmented fin crafted from a polymer composite that can be actuated in a cascading wave pattern. This arrangement replaces traditional propellers—known for their noise and tendency to startle sea life—with a biomimetic propulsion system that spreads thrust along the vehicle’s body. Initial bench trials have shown sound levels dropping by as much as 70 percent relative to conventional thruster‑based models.

The quiet swimming ability holds particular promise for ecological surveys, deep‑sea photography, and research on shy or threatened species such as certain sharks, cetaceans, and gelatinous zooplankton. By shrinking the acoustic footprint of the vehicle, researchers aim to capture more genuine behavioral observations and clearer imagery, free from the distortions caused by anthropogenic noise.

Shepherd’s team intends to run field tests later this year within a coastal marine reserve, deploying the robot to chart benthic habitats and track fish stocks. A successful demonstration could pave the way for a new class of bio‑inspired underwater platforms, fostering deeper exploration of the ocean’s hidden realms while preserving the fragile soundscape essential to many marine species.