Evaluation of a Viscoelastic Ankle-Foot Prosthesis at Slow and Normal Walking Speeds on an Able-Bodied Subject

This paper describes further improvement and preliminarily evaluation of a novel viscoelastic ankle-foot prosthesis prototype. The objective was to control the ankle hysteresis at slow and normal walking speeds.
Inspired by the ankle biomechanics, in which the hysteresis differs based on the gait speeds, a manually damping control mechanism imbedded in the prosthesis for adjusting the ankle damping at slow and normal walking speeds. The prototype was then preliminarily tested on an able-bodied subject wearing an adaptor which simulates the amputee walking. The ankle joint kinetics and kinematics were measured in a gait analysis lab at different walking speeds.
The results suggest that the viscoelastic ankle foot prosthesis prototype could provide a smooth normal-like walking for most of the measured gait characteristics in slow and normal speeds.
Therefore, it is suggested to apply a controllable damping mechanism based on the gait speeds in the design of new prosthetic feet.