This thesis presents a hierarchical geometric control approach for fast and energetically efficient bipedal dynamic walking in three-dimensional (3-D) space to enable motion planning applications that have previously been limited to inefficient quasi-static walkers. In order to produce exponentially stable hybrid limit cycles, we exploit system energetics, symmetry, and passivity through the en...

Walking is only one of many daily activities performed by patients following total knee replacement (TKR). The purpose of this study was to examine the hypotheses (a) that subject activity characteristics are correlated with knee flexion range of motion (ROM) and (b) that there is a significant difference between the subject's flexion/extension excursion throughout the day and the ISO specified...

Compared with active prostheses, passive compliant ankle prostheses offer the advantages of reduced energy consumption, a lighter weight, simple structure, and lower costs. However, although various commercial products are available, these designs do not provide adequate degrees freedom (DOFs) for movement. This paper presents ankle–foot prosthesis (CPAF) capable 2-DOF rotation during locomotio...

Introduction There remains some disagreement on the source of anterior ground reaction forces (Fx) in normal gait. For some, a passive "roll-off" results from the position of the body’s center-ofmass (COM) forward of its base of support [1], and to others, an active "push-off" results from plantarflexion power generation at the ankle [2]. The former theory essentially models the body as an inve...

Serial casting is frequently prescribed for toe-walking but that does not allow continued physical therapy (PT). This report described a child and family who chose dynamic splinting (DS) with concurrent PT for treatment. The patient presented with right hemiparesis; below average motor skills and a gait pattern of toe contact (without ankle foot orthosis). Four months of PT plus 6 hours/night o...

Why is walking easy for us and difficult for robots? The conceptual framework of traditional Artificial Intelligence, and constraints from the background of industrial robot designers, means that commercial humanoid design has often ignored the role of natural dynamics of a mechanical system, as illustrated in a Passive Dynamic Walker. We show, using a Dynamical Systems approach and Evolutionar...

This paper presents a newly developed haptic locomotion interface. The system comprises two programmable foot platforms with permanent foot machine contact. It is designed as a scalable and modular system with a unit-by-unit extensibility. The basic unit enables movements in three degrees of freedom (DOF) per foot in the sagittal plane. Each footplate can be extended to up to six degrees of fre...

Muscular rigidity and atrophy caused by long-term underactivity usually lead to foot drop, strephenopodia, foot extorsion or some other complications for the lower limb movement disorders or lower limb surgery sufferers. The ankle-foot orthosis can help patients conduct the right ankle motion mode training, inhibit spasm and prevent ankle complications. In this paper, a quasi-passive 3 DOFs ank...

In this video the walking robot ‘Dribbel’ is presented, which has been built at the Control Engineering group of the University of Twente, the Netherlands. This robot has been designed with a focus on minimal energy consumption, using a passive dynamic approach. It is a so-called four-legged 2D walker; the use of four legs prevents it from falling sideways. During the design phase extensive use...