<aside> π The Sole-Survivor is a prototype shoe attachment for Multiple Sclerosis patients who use a Bioness to aid their foot drop.
This attachment features a hexagonal defect boundary 3D-printed out of TPU to provide a strong, flexible sole which conforms to any ground, keeping the shoe and sole of the foot flat. The Sole-Survivor was made to prevent the Bioness from spasming and allow for discrete use at the userβs convenience.
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https://www.youtube.com/watch?v=enICB3XgTgU
<aside> π©Ί Our patient has multiple sclerosis and uses a Bioness to aid their foot drop. A Bioness utilizes functional electrical stimulation for muscle control in the ankle. However, this treatment loses effectiveness as the severity of MS cases decrease and tends to spasms on uneven ground. Our patient does not have the luxury of taking a walk outside for a prolonged time period, or any uneven surface, without experiencing any inconveniences.
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| Objectives | Constraints |
|---|---|
| Allows them to walk for a longer period | Discrete |
| Comfortable & eases mobility | For outdoor use |
| Can be used as an attachment | Supports human weight |
| Affordable | Function |
| Generalizable to the rest of the MS community | Increase ability for/level of activity |
<aside> π The first idea proposes the use of foam pieces embedded into a sole, allowing the shoe to conform to the ground and keep the foot leveled. This sketch was inspired by a paper that I had read, which was written by electrical and computer engineers from North South University in Bangladesh. Their model uses an Arduino microcontroller to maneuver two adjustable platforms on the sole of a shoe, which aims to prevent arthritis patients from feeling the pain inflicted by walking on an uneven surface.
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<aside> π At first, having both mechanical and computational components was considered, but we realized that this would not be feasible. This project was to be completed in approximately a month, and weighing down a wearable device with a Raspberry Pi would have resulted in an ineffective prototype. For this reason, we resorted to a solely mechanical device and no computing was involved.
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The preliminary sketch suggests the use of foam pieces to account for uneven ground.
<aside> π Foam was attached to the bottom of a shoe sole to represent a compression sole that would mould around any ground obstacles contributing to an uneven walking surface. Although not shown in the prototype, the parameters of discreteness, stability and a robust sole were established.
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Low-fidelity prototype.
<aside> π The initial print features four layers of a uniform hexagon pattern. Since Soft PLA was used, the hexagons did not print true to their shape; they came out somewhat circular.
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The first 3-D print of a uniform hexagon pattern.