“…Sound, vibration, unbalancing during operation, and complexity in body structural design are some common limitations of motor-based robotic fish. The silent, smooth, simple, and effective operation of smart material actuators such as shape memory alloys (SMAs) [ 2 , 3 , 4 , 5 , 6 ], dielectric elastomer actuators (DEA) [ 7 , 8 ], ionic polymer–metal composite (IPMC) actuators [ 9 , 10 ], etc., has attracted the attention of researchers for developing smart-material-based robotic fish [ 11 ]. It has also been observed that among all smart-actuator-based robotic fishtails, SMA spring-actuator-based robotic fishtails develop high forward thrust [ 12 ].…”