抄録
We have been developing oscillating fin propulsion type fish robots. The prototype of these robots is Tuna. The basic construction of this robot is that the rotation of the DC motor was transformed to the vibration of the tail by slider-crank mechanism, and the propulsion force is generated by the deformation of the elastic caudal fin. In this study, a concave curve generation type caudal fin was deve]oped. The structure of this fin is that the deformed shape of the silicone rubber fin was corrected to the concave curve by parallel link mechanism to improve the propulsion efficiency. The detail will he presented.