Abstract: There are many design parameters to determine a performance of a robot. Especially, in the case of the mobile robots, they require complicated motion at various environments to get high performances. In this sense, the analysis of the design parameters is the most important work to design an efficient mobile robot. In this study, we analyze the design parameters for the water-running robot. From the parametric study, we find some solutions to improve the performances of the robot. We derive dynamic equations for the water-running motion, and do a sensitivity analysis to understand the relationships between the parameters (frequency of the leg, stiffness of torsional springs that connects multi frames and mass of frames) and the performance of the water-running motion such as running speed and pitching stability. We use an orthogonal array to make various combinations of the parameters, and to reduce the number of a simulation process. As results, we summarize some solutions to improve the water-running motion. We are expecting that this study is going to be used to design robots that are operated on the water.

Key words: bioinspired robot, water-running motion, multi-body system, dynamic simulation, analysis of design parameters, sensi-tivity analysis