Meet the MantaDroid: another bio-inspired robot that emulates the swimming locomotion of manta rays. The robot can swim at speeds twice its body length per seconds for up to 10 hours. It weighs 0.7kg, measuring 63cm wide and 35cm long.
This robotic manta ray has flexible fins to move naturally in the water. It can be used for underwater search operations and other challenging missions. This project was led by Associate Professor Chew Chee Meng from the NUS Department of Mechanical Engineering.
[Source]