Additive Manufacturing of Biomechanically Tailored Meshes for Compliant Wearable and Implantable Devices

Abstract

Additive manufacturing (AM) of medical devices such as orthopedic implants and hearing aids is highly attractive because of the potential of AM to match the complex form and mechanics of individual human bodies. Externally worn and implantable tissue-support devices, such as ankle or knee braces, and hernia repair mesh, offer a new opportunity for AM to mimic tissuelike mechanics and improve both patient outcomes and comfort. Here, it is demonstrated how explicit programming of the toolpath in an extrusion AM process can enable new, flexible mesh materials having digitally tailored mechanical properties and geometry. Meshes are fabricated by extrusion of thermoplastics, optionally with continuous fiber reinforcement, using a continuous toolpath that tailors the elasticity of unit cells of the mesh via incorporation of slack and modulation of filament-filament bonding. It is shown how the tensile mesh mechanics can be engineered to match the nonlinear response of muscle. An ankle brace with directionally specific inversion stiffness arising from embedded mesh is validated, and further concepts for 3D mesh devices are prototyped.

Additive Manufacturing and Textiles—State-of-the-Art

“…One growing area of application of the 3D printed flexible parts is the health care. The generated meshes can seamlessly interact with the body (Figure 17), and thereby improve the lives of countless patients suffering from conditions ranging from ankle or other joint sprain to hernia and tremors [106]. such kind prototyping based on 3D printed manikin will be applied in the future probably only for sophisticated products.…”

“…One growing area of application of the 3D printed flexible parts is the health care. The generated meshes can seamlessly interact with the body (Figure 17), and thereby improve the lives of countless patients suffering from conditions ranging from ankle or other joint sprain to hernia and tremors [106]. An example of ankle brace was developed that shows the potential of controlled nonlinear tensile response by letting the ankle move freely unless it inverts to an excessive extent as well as a glove with an embedded mesh designed to conform to the hand (see Figure 18) [17].…”

“…An example of ankle brace was developed that shows the potential of controlled nonlinear tensile response by letting the ankle move freely unless it inverts to an excessive extent as well as a glove with an embedded mesh designed to conform to the hand (see Figure 18) [17]. One way of the improvement of the drape ability of the solid parts is modification of the tool path so, that the fiber cool down before it touch the previous placed fiber in some areas [106]. The so build filament path are not connected and can slide relative to each other which results noticeably greater drape (10 mm scale bar) ( Figure 19A).…”

“…One way of the improvement of the drape ability of the solid parts is modification of the tool path so, that the fiber cool down before it touch the previous placed fiber in some areas [106]. The so build filament path are not connected and can slide relative to each other which results noticeably greater drape (10 mm scale bar) ( Figure 19a).…”

DefeXtiles

“…Pattinson et. al [19] devised an approach to 3D print flexible mesh materials with digitally tailored mechanical properties, but this horizontal printing approach limited the size and forms possible.…”