Fabrication of Customized Ankle Foot Orthosis (AFO) by Reverse Engineering Using Fused Deposition Modelling

Abstract

Ankle foot orthosis (AFO) is an assistive device used for support and correction of musculoskeletal structure. This research focuses on the development of a methodology to design and fabricate a patient-specific AFO for drop foot by redressing the geometrically 3D scanned data cloud of patient’s lower limb. Unlike traditional plaster moulding technique, this technique has leverage of fast and precise AFO generation. It consists of acquisition of geometrical and anatomical data of patient’s limb with the help of 3D scanning. Post-processing of data points is done to obtain refined limb geometry. Design of AFO from point cloud is done according to structural needs and requisite correction. An analysis based on the planter flexion and dorsiflexion movement of AFO and rotation about ankle in saggital plane are conducted on Fusion360™. Comparison of traditionally used polypropylene (PP) material is done with acrylonitrile butadiene styrene (ABS) and poly-lactic acid (PLA) based on the predefined tests. FEA enables to obtain result conforming to design aspect, and finally, fabrication of AFO using fused deposition modelling is done.