iSplash: realizing fast Carangiform swimming to outperform a real fish

Abstract

This paper focuses on the linear swimming motion of Carangiform fish and presents two novel prototypes: iSplash-I and iSplash-II, which have overcome some of the previously known challenges, in particular the straight line swimming speed of robotic fish. The first generation iSplash-I improved the kinematic pattern by deploying a full-body length swimming motion to coordinate anterior, mid-body, and posterior displacements. The second generation iSplash-II achieved consistent untethered stabilized swimming speeds of 11.6 BL/s (i.e., 3.7 m/s), with a frequency of 20 Hz during the field trials, outperforming real carangiform fish in terms of average maximum velocity (measured in body lengths/second) and endurance, the duration that top speed is maintained.