Theoretical and Experimental Issues in Biped Walking Control Based on Passive Dynamics

Passive ankle foot orthoses (AFOs) are often prescribed for children with cerebral palsy (CP) to assist locomotion, but predicting how specific device designs will impact energetic demand during gait remains challenging. Powered AFOs have been shown to reduce energy costs of walking in unimpaired adults more than passive AFOs, but have not been tested in children with CP. The goal of this study...

This paper explores the use of a single passive design to stabilize frontal plane dynamics for 3D biped walking across a range of forward velocities and/or step lengths. Particular goals are to determine if design of sagittal plane control can be done independently from design of frontal plane stabilization mechanisms, and to explore how dynamic coupling between the two planned motions affects ...

This paper presents the simplest walking model with an upper body. The model is a passive dynamic walker, i.e. it walks down a slope without motor input or control. The upper body is confined to the midway angle of the two legs. With this kinematic constraint, the model has only two degrees of freedom. The model achieves surprisingly successful walking results: it can handle disturbances of 8% ...

Previous research has shown that passive (or ballistic) walking is an energetic efficient and mechanical cheap way of walking. Therefore ballistic walking would be suitable for apphcauons in rehabilitation technology and autonomous robots. Successful application would require a smooth hip trajectory in ordet to protect respectively the patient or electronics against large velocity changes due t...

Human walking can be approximated as a mechanical process governed by Newton’s laws of motion, and not controlled. Tad McGeer first demonstrated, and we have confirmed, that a two-dimensional legged mechanism with four moving parts can exhibit stable, human-like walking on a range of shallow slopes with no actuation and no control (energy lost in friction and collisions is recovered from gravit...

It was shown in Spong [1999b] that the passive gaits for a planar 2DOF biped walking on a shallow slope (Goswami et al. [1995]) can be made slope invariant by a passivity based control that compensates only the gravitational torques acting on the biped. In this paper we extend these results to the general case of a 3-D, n-DOF robot. We show that if there exists a passive walking gait, i.e., if ...

Abstract It is well known that passive dynamic walking shows chaotic behavior owing to changes in the environment. In addition, when environment continuously during walking, “adaptive behaviors” which stride angle itself an attempt keep walking. These behaviors are very interesting and useful for legged robot design. However, studies on preceded only by numerical simulations. For this reason, i...

A two-straight-legged walking mechanism with flat feet is designed and built to study the passive dynamic gait. It is shown that the mechanism having flat feet can exhibit passive dynamic walking as those with curved feet, but the walking efficiency is significantly lower. It is also shown that the balancing mass and its orientation are etfective for controlling side-to-side rocking and yaw, wh...