Theauthors have built the first three-dimensional, kneed, two-legged, passive-dynamic walking machine. Since the work of Tad McGeer in the late 1980s, the concept of passive dynamics has added insight into animal locomotion and the design of anthropomorphic robots. Various analyses and machines that demonstrate efficient humanlike walking have been developed using this strategy. Human-like pass...

Control schemes for powered ankle-foot prostheses rely upon fixed torque-ankle state relationships obtained from measurements of intact humans walking at target speeds and across known terrains. Although effective at their intended gait speed and terrain, these controllers do not allow for adaptation to environmental disturbances such as speed transients and terrain variation. Here we present a...

This paper addresses some performance limits of the kneed and non-kneed passive-dynamic walking machines discovered by McGeer [10, 11]. Energetic inefficiency is measured by the slope γ needed to sustain gait, with γ = 0 being perfectly efficient. We show some necessary conditions on the walker mass distribution to achieve perfectly efficient walking. From our experience and study of a simpler ...

INTRODUCTION Peripheral arterial disease (PAD) is defined by atherosclerotic plaque buildup and subsequent blockages along the arterial walls of the extremities[1]. The narrowing of the arteries leads to reduced blood flow to the leg musculature upon exertion clinically resulting in complaints of leg pain. This pain, known as claudication, stops once muscular exertion ceases and metabolic deman...

When ascending (descending) a slope, positive (negative) work must be performed to overcome changes in gravitational potential energy at the center of body mass (COM). This modifies the pendulum-like behavior of walking. The aim of this study is to analyze how energy exchange and mechanical work done vary within a step across slopes and speeds. Ten subjects walked on an instrumented treadmill a...

A simple harmonic oscillator model is proposed to describe the mechanical power involved in human locomotion. In this framework, by taking into account the anthropometric parameters of a standard individual, we are able to calculate the speed-power curves in human walking. The proposed model accounts for the well known Margaria’s law in which the cost of the human running (independent from the ...

Objectives This paper presents an optimal trajectory generation method for the biped walking on inclined surfaces by changing some boundary conditions. The minimal energy is used as a criterion to propose a dynamically stable and optimal trajectory generation method for the impactless biped walking. Methods A biped robot should be able to navigate artificial environments including stair-cases, ...