Airy Arm 2.0

thingiverse

Hemiparesis is a medical condition that causes muscle weakness resulting from brain or head trauma, typically due to a stroke. However, it can also be caused by other diseases, such as cerebral palsy, multiple sclerosis, or cancer. People with hemiparesis often have difficulty feeling their extremities and clenching their fingers. This design was motivated by the need to provide people with hemiparesis and those rehabilitating from finger injuries that may cause nerve damage with the ability to extend and retract their fingers. The goal of this design is to provide a device that attaches to the arm and allows the user to control their fingers. Straightening the arm will cause the fingers to extend, while bending the arm at the elbow will cause them to retract and clench. To accomplish this, CAD models have been designed to attach to the upper arm (above the elbow), hand, fingers, and fingertips. Strings are used to connect these parts to each finger. A design is available on Thingiverse, an open-source repository, that serves a similar purpose to the proposed design. However, it uses a complex design where all components were designed to require thermoforming to shape the parts to the user's body. This resulted in larger-than-necessary parts intended to provide better coverage around the arm. However, in practice, thermoforming cannot perfectly mold parts to the body's geometry, leading to air gaps and irregularities. Additionally, this design used more parts than required for its intended function. The proposed design aims to simplify and improve the existing design by reducing the required material, eliminating unnecessary components, and simplifying the overall design to better focus on the primary function of assisting in the movement of the fingers. All parts of the new Airy Arm are 3D printed and can be secured by Velcro straps with no need for thermoforming or using screws or other fasteners. Our design produced a redesigned device that still can open the fingers but requires much less manufacturing time and materials.