Biomorphic propulsion system diving thunniform robotic fish
This work addresses the design of efficient propulsion systems for underwater robotics, but it appears incremental as it builds on existing biomimetic principles without claiming major breakthroughs.
The researchers developed a biomorphic propulsion system for an underwater robotic fish using an elastic chord and tail fin to mimic thunniform locomotion, and they experimentally measured how tail oscillation amplitude and frequency affect the fish's velocity.
A biomorphic propulsion systemfor underwater robotic fish is presented. The system is based on a combination of an elastic chord with a tail fin fixed on it. The tail fin is connected to servomotor by two symmetric movable thrusts simulating muscle contraction. The propulsion system provides oscillatory tail movement with controllable amplitude and frequency. Tail oscillations results in translational movement of the robotic fish implementing the thunniform principle of locomotion. The shape of the body of the robotic fish and the tail fin were designed using computational model simulating virtual body in an aquatic medium. A prototype of robotic fish device was constructed and tested in experimental conditions. Dependencies of fish velocity on the amplitude and frequency of tail oscillations were analyzed.