ScaFi robot mimics fish swimming with scalable design

Engineers from New York University and the École Polytechnique Fédérale de Lausanne have developed ScaFi, a biomimetic aquatic robot inspired by fish such as cod and mackerel. The design utilizes subcarangiform swimming patterns, where the majority of the body movement is concentrated toward the tail.

A key innovation of ScaFi is its scalable architecture. The robot can be constructed in various sizes, ranging from approximately 60 centimeters to nearly 3 meters in length, without requiring a complete redesign of its propulsion mechanism. This scalability allows the robot to be used in diverse environments, from small streams to large bodies of water.

The robot features a rigid front section and a flexible, extensible tail made of fiberglass rods. A single motor pulls two tendons that cross near the end of the tail, creating the S-shaped curves necessary for fish-like movement. Unlike traditional underwater vehicles that use propellers, ScaFi moves water by flexing its body.