Meet the BionicFinWave: an underwater robot that uses a fin drive to move . It maneuvers through a pipe system through undulating fin movement and sends data wirelessly to the outside world. BionicFinWave’s fins are cast from silicone, so they are extremely flexible. As the researchers explain:
the two fins on the left and right are each fastened to nine small lever arms. These in turn are driven by two servo motors located in the body of the underwater robot. Two attached crankshafts transfer the force to the levers in such a way that the two fins can move individually. They can thereby generate different wave patterns
These robots also have 3D printed components. The front of the body houses the circuit board with processor and remote module, a pressure sensor, and ultrasound sensors.