Parametric excitation of a biped robot as an inverted pendulum

Abstract

For stable gait generation on the level floor, restoring mechanical energy lost by heel-strike collision at the ground is necessary. Parametric excitation principle is one of the solutions. Harata et al. applied this principle to a knee actuated robot to achieve parametric excitation by bending and extending the knee, and succeeded in generating a sustainable biped gait by computer simulation. Although only the dynamics of the swing-leg was considered in the method, the stance-leg's dynamics also affects the swing-leg's dynamics. Therefore we considered the whole dynamics of the robot in this paper. Therefore, we dealt with the robot's center of mass as an inverted pendulum and achieved stable gait generation by parametric excitation of the inverted pendulum. The resultant energy efficiency was increased significantly.

Parametrically excited inverted double pendulum and efficient bipedal walking with an upper body

“…Then we applied parametric excitation of an inverted pendulum to this virtually inverted pendulum. 8,9 We derived the optimal trajectory of parametrically excited inverted pendulum and this trajectory is shown in Fig. 1.…”

“…We proposed to apply parametric excitation of an inverted pendulum to a biped robot to consider whole body dynamics of the robot. 8 We dealt with the robot's total center of mass as an inverted pendulum and controlled the trajectory of mass center to be closer to the optimal trajectory of a parametrically excited inverted pendulum. In addition, we proposed a new target trajectory to realize more energy efficient walking.…”

Motion Planning for Humanoid Robot Based on Hybrid Evolutionary Algorithm

“…In the cycle of supporting with one leg, the robot can be regarded to the motion of multi-stage inverted pendulum [15] . Assume the weight of robot's connecting rod is even, so the coordinate ( )( ) , 1, 2...,7…”

High-speed and energy-efficient biped locomotion based on Virtual Slope Walking

“…Moreover, Asano and Luo (2008) propose the level walking by pumping the swing leg from the viewpoint of potential energy restoration, demonstrating a potential realization of energy efficient and high speed walking. Furthermore, Honjo et al (2008) and Harata et al (2009) introduce the parametric excitation for potential energy restoration by extending and shortening the stance leg in powered walking. This presents a more energy-efficient gait than just pumping the swing leg.…”