Modal analysis of composite prosthetic energy-storing-and-returning feet: An initial investigation

Authors: Noroozi, S., Sewell, P., Rahman, A.G.A., Vinney, J., Chao, O.Z. and Dyer, B.

Journal: Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology

Volume: 227

Issue: 1

Pages: 39-48

eISSN: 1754-338X

ISSN: 1754-3371

DOI: 10.1177/1754337112439274

Abstract:

The desire of individuals with a lower-limb amputation to participate in sports, coupled with the high demands of athletics, has resulted in the development of energy-storing-and-returning feet, capable of storing energy during stance and returning it to the individual in late stance to assist in forward propulsion. However, little attention has been paid to date to advance the understanding of their dynamic characteristics (natural frequencies, mode shapes and damping) during running. The evaluation of such parameters is now urgently required, as the use of energy-storing-and-returning feet is now being investigated through legal and justice systems to determine participation of amputee athletes using them at the Olympic Games. This paper presents a study of the dynamic characteristics of two commercially available Elite Blade composite feet (solid and split foot). A full modal analysis of the feet was conducted with varying masses attached to them, representing different body masses. The study showed that natural frequencies close to typical running step frequency can be achieved with simple control of the mass or stiffness. It was concluded that further study of the dynamic characteristics could result in a significant change in the design, development and the attitude towards the use of composite prosthetic feet. This initial study has highlighted the key questions that need to be answered to fully understand the dynamic characteristics and inform designers on how to tune a foot to match an amputee's gait and body condition. © IMechE 2012.

Source: Scopus

Modal analysis of composite prosthetic energy-storing-and-returning feet: an initial investigation

Authors: Noroozi, S., Sewell, P., Rahman, A.G.A., Vinney, J., Chao, O.Z. and Dyer, B.

Journal: PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART P-JOURNAL OF SPORTS ENGINEERING AND TECHNOLOGY

Volume: 227

Issue: P1

Pages: 39-48

eISSN: 1754-338X

ISSN: 1754-3371

DOI: 10.1177/1754337112439274

Source: Web of Science (Lite)

Modal analysis of composite prosthetic energy-storing-and-returning feet: an initial investigation

Authors: Noroozi, S., Sewell, P., Vinney, J., Dyer, B.T.J., Rahman, A.G.A. and Zhi Chao, O.

Journal: Proceedings of the Institution of Mechanical Engineers Part P: Journal of Sports Engineering and Technology

ISSN: 1754-3371

Abstract:

The desire of individuals with a lower-limb amputation to participate in sports coupled with and the high demands of athletics, has resulted in the development of energy-storing-and-returning feet, capable of storing energy during stance and returning it to the individual in late stance to assist in forward propulsion. However, little attention has been paid to date to advance the understanding of their dynamic characteristics (natural frequencies, mode shapes and damping) during running. The evaluation of such parameters is now urgently required when the use of energy-storing-and-returning feet is now being investigated through legal and justice systems to determine participation of amputee athletes using them at the Olympic Games. This paper presents a study of the dynamic characteristics of two commercially available Elite Blade composite feet (solid and split foot). A full modal analysis of the feet was conducted with varying masses attached to them, representing different body masses. The results indicate that as the mass attached to the foot increases the natural frequencies of the mass foot system decreases and that the feet have close to linear stiffness characteristics. The study showed that natural frequencies close to typical running step frequency can be achieved with simple control of the mass or stiffness. It was concluded that further study of the dynamic characteristics could result in a significant change in the design, development and the attitude towards the use of composite prosthetic feet. This initial study has highlighted the key questions that need to be answered to fully understand the dynamic characteristics and inform designers on how to tune a foot to match an amputee’s gait and body condition.

http://www.uk.sagepub.com/journals/Journal202029

Source: Manual

Preferred by: John Vinney and Siamak Noroozi