Design of an automated device to measure sagittal plane stiffness of an articulated ankle-foot orthosis

Kobayashi, T; Leung, A; Akazawa, Y; Naito, H; Tanaka, M; Hutchins, S

Abstract

The purpose of this study was to design a new automated stiffness measurement device which could perform a simultaneous measurement of both dorsi- and plantarflexion angles and the corresponding resistive torque around the rotational centre of an articulated ankle-foot orthosis (AAFO). This was achieved by controlling angular velocities and range of motion in the sagittal plane. The device
consisted of a hydraulic servo fatigue testing machine, a torque meter, a potentiometer, a rotary plate and an upright supporter to enable an AAFO to be attached to the device via a surrogate shank. The accuracy of the device in reproducing the range of motion and angular velocity was within 4% and 1% respectively in the range of motion of 308 (158 plantarflexion to 158 dorsiflexion) at the angular velocity of 108/s, while that in the measurement of AAFO torque was within 8% at the 08 position. The device
should prove useful to assist an orthotist or a manufacturer to quantify the stiffness of an AAFO and
inform its clinical use.

Citation

Kobayashi, T., Leung, A., Akazawa, Y., Naito, H., Tanaka, M., & Hutchins, S. Design of an automated device to measure sagittal plane stiffness of an articulated ankle-foot orthosis. Prosthetics and Orthotics International, 34(4), 439-448. https://doi.org/10.3109/03093646.2010.495370

• Journal Article Type: Article
• Deposit Date: May 11, 2011
• Journal: Prosthetics and Orthotics International
• Print ISSN: 0309-3646
• Publisher: SAGE Publications
• Peer Reviewed: Peer Reviewed
• Volume: 34
• Issue: 4
• Pages: 439-448
• DOI: https://doi.org/10.3109/03093646.2010.495370
• Publisher URL: http://dx.doi.org/10.3109/03093646.2010.495370