Abstract
In order to clarify the unsteady characteristics of the fluid forces acting on swimmer, an underwater swimming humanoid was developed. The robot was actuated by 20 motors and could perform the various human swimming motions. In addition, it has the same body proportion and appearance with half size of real human for the accurate measurement of drag force. To mimic the real human body, we scanned swimmer body and made robot cases using the data. The robot cases were printed by rapid prototype machine and were waterproofed by coating of waterproofing material. We developed gear housing for the waterproofing of motors and saving spaces in the robot. Various swimming motions were realized on the land. The developed robot's specific gravity was a little smaller than water and it could float without any buoyancy equipment on the water.
