Spontaneous Rhythmic Behavior Generation in Robot Locomotion Based on Mechanical Stabilization

Animals exhibit a variety of gait patterns that vary with locomotor speed and energy efficiency. Although a variety of gait patterns have been studied, the mechanism of gait generation has remained vague. In this study, we performed ground reaction force equalization for stable locomotion by developing a one-input, two-output leg-equipped robot with a differential gear. The developed robot can tolerate angular velocity differences and equalize the torque transmitted to the legs. To investigate the possibility of rhythm generation based on ground reaction force equalization, hardware experiments and mathematical analysis were conducted using a nonlinear system. The robot experiments and theoretical analysis show that the robot can spontaneously generate rhythm by equalizing the ground reaction force.