Selective Laser Sintering of Passive Dynamic Ankle-Foot Orthoses
Abstract
Passive dynamic ankle-foot orthoses (AFO’s) are used to improve gait performance in
those with various neuromuscular disorders. An important design characteristic of passive
dynamic AFOs is the storage and release of elastic energy within its structure to help satisfy the
energetic demands of walking. Thus, minimizing energy dissipation through internal friction is a
fundamental criterion for selecting the appropriate AFO material. This study compared the
mechanical damping of a carbon-fiber AFO to three geometrically identical AFO’s fabricated
using selective laser sintering with different materials. Mechanical damping characteristics
ranked the materials as Nylon 11 (best), followed by DuraformTM PA and DuraformTM GF
(worst).