Tamiya 70218 Swimming Manta Ray

This Educational Construction series kit creates an exciting swimming robot with a large, flexible fin-shaped plate that moves up and down to propel it through water and make it look just like a manta ray. The fin piece is powered by a submarine motor. Specifications

 

Assembly kit. Length: 160mm, width: 148mm, height: 55mm.

Intuitive and easily-accessible assembly process means simple building of the kit, even for beginners.

Submarine motor powers the fin part via a shaft.

The tail fin acts as a rudder, and moving it allows you to alter the direction in which the manta ray travels.

Requires one AAA battery.

The rotary motion of the underwater gearbox is changed to a reciprocating motion with the crank plate, and the left and right fins are moved as if they were flapping.

You can change the direction of travel by changing the angle of the tail.

https://www.youtube.com/watch?v=UQa7HKPgVzc&feature=emb_logo