In recent years, the aging of society has led to challenges such as ensuring adequate facility capacity and promoting health maintenance for the elderly. Consequently, there has been a growing demand for rehabilitation and fitness equipment suitable for use in limited spaces such as homes. In a previous study, a hexapod mobile robot, equipped with six tetrahedral-shaped pneumatic soft actuators (TSAs), was developed as a core training device to address these issues. However, the robot’s gait was investigated experimentally via a trial-and-error process. Hence, it is necessary to examine the stability of the gait. In this study, a straightforward model is presented for gait analysis of the mobile robot. Furthermore, the stability of the gait is demonstrated based on the analysis, and a more efficient gait with a sufficient stability margin is introduced.

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