In this paper, we introduce a shape-based, time-scale invariant feature descriptor for 1-D sensor signals. The time-scale invariance of the feature allows us to use feature from one training event to describe events of the same semantic class which may take place over varying time scales such as walking slow and walking fast. Therefore it requires less training set. The descriptor takes advanta...

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 ...

Traditional biped walkers based on passive dynamic walking usually have flat or circular feet. This foot contact may be modelled with an effective rocker represented as a roll-over shape to describe the function of the knee-ankle-foot complex in human ambulation. Mahmoodi et al. [1] has modelled this roll-over shape as a discretized set of pivot points. In this paper, Lagrangian mechanics are u...

Many of today’s successful biped robots are controlled based on the Zero Moment Point (ZMP) method, which generates robust locomotion for flat-footed bipeds on a controlled environment. These controllers usually generate slow gaits with a low energy efficiency which do not look natural or human-like. In contrast, Passive Dynamic Walkers [2], [5] are fast, efficient and resemble human walking. M...

This paper presents some of the ground mobile robots under development at the Robotics and Mechanisms Laboratory (RoMeLa) at Virginia Tech that use biologically inspired novel locomotion strategies. By studying nature's models and then imitating or taking inspiration from these designs and processes, we apply and implement new ways for mobile robots to move. Unlike most ground mobile robots tha...

BACKGROUND This study aimed to examine both GPS-determined and self-reported walking, cycling and passive transport in leisure time during week- and weekend-days among 10 to 12-year old children. Comparisons between GPS-determined and self-reported transport in leisure time were investigated. Second, associations between parental perceptions of the neighborhood environment and GPS-determined wa...

Locomotor malfunction represents a major problem in some neurological disorders like stroke and spinal cord injury. Robot-assisted walking devices have been used during rehabilitation of patients with these ailments for regaining and improving walking ability. Previous studies showed the advantage of brain-computer interface (BCI) based robot-assisted training combined with physical therapy in ...

Currently, passive robots are designed following a trial and error process in which the existence of a stable walking cycle for a given passive robot’s model is analyzed using Poincaré maps. The standard stability analysis procedure suffers from discretization aliasing, and it is not able to deal with complex passive models. In this paper a methodology that allows finding conditions on the robo...

OBJECTIVE Although variable-damping knee prostheses offer some improvements over mechanically passive prostheses to transfemoral amputees, there is insufficient evidence that such prostheses provide advantages at self-selected walking speeds. In this investigation, we address this question by comparing two variable-damping knees, the hydraulic-based Otto Bock C-leg and the magnetorheological-ba...

BACKGROUND Active transport is a convenient way to incorporate physical activity in adolescents' daily life. The present study aimed to investigate which psychosocial and environmental factors are associated with walking, cycling, public transport (train, tram, bus, metro) and passive transport (car, motorcycle, moped) over short distances (maximum eight kilometres) among older adolescents (17-...