scholarly journals Algorithm to estimate the knee angle in normal gait: trajectory generation approach to intelligent transfemoral prosthesis

2016 ◽  
Vol 37 (3) ◽  
Keyword(s):  
Trajectory Generation ◽  
Knee Angle ◽  
Normal Gait ◽  
Transfemoral Prosthesis

Myoelectric Torque Control of an Active Transfemoral Prosthesis During Stair Ascent

2011 ◽  
Author(s):  
Carl D. Hoover ◽  
Kevin B. Fite ◽  
George D. Fulk ◽  
Donald W. Holmes
Keyword(s):  
Impedance Control ◽  
Torque Control ◽  
Motion Capture Data ◽  
Clinical Tests ◽  
Joint Kinetics ◽  
Set Point ◽  
Stair Ascent ◽  
Normal Gait ◽  
Stiffness And Damping ◽  
Transfemoral Prosthesis

This paper presents experimental results of a myoelectric impedance controller designed for reciprocal stair ascent with an active-knee powered transfemoral prosthesis. The controller is modeled from non-amputee (normal) motion capture data, estimating knee torque with a linear two-state (stance/swing) impedance control form that includes proportional myoelectric torque control. The normal gait model is characterized by small stiffness and damping in both stance and swing, a low angle set-point in stance, a high angle set-point in swing, and proportional myoelectric control in stance but not swing. Clinical tests with a single unilateral transfemoral amputee indicate good performance of the controller; however, subject feedback suggests a reduction in the extensive myoelectric torque parameter and the need for constant, balanced myoelectric torque parameters in both stance and swing. Average prosthesis knee joint kinetics from a stairwell test using the amputee-tuned controller compare favorably with non-amputee gait data.

scholarly journals Technology Efficacy in Active Prosthetic Knees for Transfemoral Amputees: A Quantitative Evaluation

2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
Amr M. El-Sayed ◽  
Nur Azah Hamzaid ◽  
Noor Azuan Abu Osman
Keyword(s):  
Sensory System ◽  
Control Technique ◽  
Strategic Integration ◽  
Normal Gait ◽  
Functional Development ◽  
Gait Parameters ◽  
Core Elements ◽  
Technical Examination ◽  
Prosthetic Knees ◽  
Transfemoral Prosthesis

Several studies have presented technological ensembles of active knee systems for transfemoral prosthesis. Other studies have examined the amputees’ gait performance while wearing a specific active prosthesis. This paper combined both insights, that is, a technical examination of the components used, with an evaluation of how these improved the gait of respective users. This study aims to offer a quantitative understanding of the potential enhancement derived from strategic integration of core elements in developing an effective device. The study systematically discussed the current technology in active transfemoral prosthesis with respect to its functional walking performance amongst above-knee amputee users, to evaluate the system’s efficacy in producing close-to-normal user performance. The performances of its actuator, sensory system, and control technique that are incorporated in each reported system were evaluated separately and numerical comparisons were conducted based on the percentage of amputees’ gait deviation from normal gait profile points. The results identified particular components that contributed closest to normal gait parameters. However, the conclusion is limitedly extendable due to the small number of studies. Thus, more clinical validation of the active prosthetic knee technology is needed to better understand the extent of contribution of each component to the most functional development.

scholarly journals Influence of speed on gait parameters and on symmetry in transtibial amputees

1996 ◽  
Vol 20 (3) ◽  
pp. 153-158 ◽  
Author(s):  
E. Isakov ◽  
H. Burger ◽  
J. Krajnik ◽  
M. Gregoric ◽  
C. Marincek
Keyword(s):  
Heel Strike ◽  
Knee Angle ◽  
Gait Characteristics ◽  
Load Response ◽  
Normal Gait ◽  
Gait Parameters ◽  
In Trans ◽  
High Level ◽  
Transtibial Amputees ◽  
Design Guidance

Normal gait is characterised by a high level of inter-leg symmetry of gait parameters. Therefore, efforts in rehabilitation of amputees are directed at the construction of a prosthesis which provides normal leg function and allows a more symmetrical gait. Analysis of the gait of trans-tibial amputees was performed when they were ambulating at their own freely selected speed and at a faster speed. The effect of speed on selected gait parameters in each leg was evaluated and the influence on symmetry established by comparing the inter-leg changes for each of the selected parameters. The faster gait trail affected significantly all temporal and distance parameters in both legs but not the level of symmetry between legs. At the faster speed, the hip angles at heel-strike and during swing and the knee angle during load response, in the normal leg, and the knee angle during swing in the amputated leg, all increased significantly. Speed of gait significantly affected symmetry between knee angles as reflected by the increased differences measured during load response (from 2.62 ±5.2 to 7.06 ±4.2 degrees) and during toe-off (from 1.80 ±7.4 to 9.50 ±9.1 degrees). Timing and sequence of selected gait events, as related to stride time, were not significantly affected by speed of gait. These results might contribute to a better understanding of gait characteristics in trans-tibial amputees and provide design guidance for prosthetic components.

Trajectory Generation for Distributed Electric Propulsion Vehicles with Propeller Synchronization

2021 ◽  
Author(s):  
Andrew Patterson ◽  
Kasey A. Ackerman ◽  
Naira Hovakimyan ◽  
Irene M. Gregory
Keyword(s):  
Electric Propulsion ◽  
Trajectory Generation

Control Theory, Dynamics, and Continuous Interaction

2018 ◽  
Author(s):  
Roderick Murray-Smith
Keyword(s):  
Control Theory ◽  
Human Computer Interaction ◽  
Systems Theory ◽  
Dynamic Systems ◽  
Trajectory Generation ◽  
Interaction Techniques ◽  
Dynamic Systems Theory ◽  
Classical Work ◽  
Continuous Interaction

This chapter reviews the role of theory and dynamic systems theory for understanding common interaction techniques including: targetting, trajectory generation, panning, scrolling and zooming. It explains how can be seen to be at the foundations of Human–Computer Interaction and might be essential for making progress in novel forms of interface. It reinterprets Fitts’ classical work with theoretic tools. It also highlights the limitations of theory for design of human–computer loops.

Sign in / Sign up

Export Citation Format

Share Document