Fin Ray Gripper

A compliant gripper, inspired by fish fins, whose fingers bend around an object automatically under side pressure.

A Fin Ray finger is a triangular frame whose two outer edges are connected by a series of crosswise ribs, a structure inspired by fish fins (the Fin Ray Effect). When an object presses against the finger from the side, the finger doesn't just get squashed and pushed away — it bends toward the object instead, automatically conforming to its contour. This means a single, ordinary two-finger open/close motion is enough to gently wrap around fruit, bottles, and other irregularly shaped objects over a fairly large contact area, with no extra sensors or complex control needed. It's usually made from soft plastic or 3D-printed, is cheap, and is often used as a drop-in fingertip replacement on a two-finger gripper — a passively compliant type of soft gripper.

ExampleSwapping a parallel gripper's rigid fingertips for two 3D-printed Fin Ray fingers lets it hold a tomato firmly without crushing it.

Also called

Fin Ray Effect Gripper

Related

Soft Gripper · Parallel Jaw Gripper · Adaptive (Underactuated) Gripper · Compliance · Gripper

Sources

Soft robotics（含 Fin Ray 抓手介绍）- Wikipedia (Chinese)