In this paper, a powered ankle-foot prosthesis with nonlinear parallel spring mechanism is developed. The parallel spring mechanism is used for reducing the energy consumption and power requirement of the motor, at the same time simplifying control of the prosthesis. To achieve that goal, the parallel spring mechanism is implemented as a compact cam-spring mechanism that is designed to imitate human ankle dorsiflexion stiffness. The parallel spring mechanism can store the negative mechanical energy in controlled dorsiflexion (CD) phase and release it to assist the motor in propelling a human body forward in a push-off phase (PP). Consequently, the energy consumption and power requirements of the motor are both decreased. To obtain this desired behavior, a new design method is proposed for generating the cam profile. Unlike the existing design methods, the friction force is considered here. The cam profile is decomposed into several segments, and each segment is fitted by a quadratic Bezier curve. Experimental results show that the cam-spring mechanism can mimic the desired torque characteristics in the CD phase (a loading process) more precisely. Finally, the developed prosthesis is tested on a unilateral below-knee amputee. Results indicate that, with the assistance of the parallel spring mechanism, the motor is powered off and control is not needed in the CD phase. In addition, the peak power and energy consumption of the motor are decreased by approximately 37.5% and 34.6%, respectively.
Skip Nav Destination
Article navigation
May 2018
Design Innovation Paper
Design of Powered Ankle-Foot Prosthesis With Nonlinear Parallel Spring Mechanism
Fei Gao,
Fei Gao
Mem. ASME
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: fgao2@mae.cuhk.edu.hk
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: fgao2@mae.cuhk.edu.hk
Search for other works by this author on:
Yannan Liu,
Yannan Liu
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: lyn2014hk@gmail.com
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: lyn2014hk@gmail.com
Search for other works by this author on:
Wei-Hsin Liao
Wei-Hsin Liao
Professor
Fellow ASME
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: whliao@cuhk.edu.hk
Fellow ASME
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: whliao@cuhk.edu.hk
Search for other works by this author on:
Fei Gao
Mem. ASME
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: fgao2@mae.cuhk.edu.hk
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: fgao2@mae.cuhk.edu.hk
Yannan Liu
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: lyn2014hk@gmail.com
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: lyn2014hk@gmail.com
Wei-Hsin Liao
Professor
Fellow ASME
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: whliao@cuhk.edu.hk
Fellow ASME
Department of Mechanical and Automation Engineering,
The Chinese University of Hong Kong,
Shatin 999077, NT, Hong Kong
e-mail: whliao@cuhk.edu.hk
1Corresponding author.
Contributed by the Design Innovation and Devices of ASME for publication in the JOURNAL OF MECHANICAL DESIGN. Manuscript received June 22, 2017; final manuscript received January 30, 2018; published online March 9, 2018. Assoc. Editor: Oscar Altuzarra.
J. Mech. Des. May 2018, 140(5): 055001 (8 pages)
Published Online: March 9, 2018
Article history
Received:
June 22, 2017
Revised:
January 30, 2018
Citation
Gao, F., Liu, Y., and Liao, W. (March 9, 2018). "Design of Powered Ankle-Foot Prosthesis With Nonlinear Parallel Spring Mechanism." ASME. J. Mech. Des. May 2018; 140(5): 055001. https://doi.org/10.1115/1.4039385
Download citation file:
Get Email Alerts
Large Language Models for Predicting Empathic Accuracy Between a Designer and a User
J. Mech. Des (April 2025)
Repurposing as a Decommissioning Strategy for Complex Systems: A Systematic Review
J. Mech. Des (May 2025)
A Dataset Generation Framework for Symmetry-Induced Mechanical Metamaterials
J. Mech. Des (April 2025)
Related Articles
A General Modeling Methodology for the Quasistatic Behavior of Spiral Torsion Springs
J. Mech. Des (January,2021)
A Universal Ankle–Foot Prosthesis Emulator for Human Locomotion Experiments
J Biomech Eng (March,2014)
Avoiding Early Failures in Conjugate Cam Mechanism by Means of Different Design Strategies
J. Mech. Des (January,2016)
Enhanced Formulae for Determining Both Free Length and Rate of Cylindrical Compression Springs
J. Mech. Des (February,2016)
Related Proceedings Papers
Related Chapters
History of Vascular Graft Development
Vascular Graft Update: Safety and Performance
Imbalance Torque Observer of Stabilized Platform Design based on EKF Identification
International Conference on Control Engineering and Mechanical Design (CEMD 2017)
Stable Analysis on Speed Adaptive Observer in Low Speed Operation
International Conference on Instrumentation, Measurement, Circuits and Systems (ICIMCS 2011)