Tailored Torsion and Bending-Resistant Avian-Inspired Structures

The escalating demand for torsion- and bending-resistant structures paired with the need for more efficient use of materials and geometries, have led to novel bio-inspired ingenious solutions. However, lessons from Nature could be as inspiring as they are puzzling: plants and animals offer an enormous range of promising but hierarchically complex configurations. Avian bones are prominent candidates for addressing the torsional and bending issue. They present a unique intertwining of simple components: helicoidal ridges and crisscrossing struts, able to bear flexural and twisting actions of winds. Here, it is set how to harmonically move from the natural to the engineering level to formalize and analyze the biological phenomena under controlled design conditions. The effect of ridges and struts is isolated and combined toward tailored torsion and bending-resistant arrangements. Then the biological level is revisited to extrapolate the avian allometric design approach and is translated into multiscale lightweight structures at the engineering level. This study exploits the complexity of Nature and the scalability that characterizes the evolutionary design of bird bones through the design and fabrication versatility allowed by additive manufacturing technologies. This paves the way for exploring the transferability of the proposed solution at multiple engineering scales

Design and 3D printing of a modular phantom of a uterus for medical device validation

PurposeThe purpose of this study is to describe the design and validation of a three-dimensional (3D)-printed phantom of a uterus to support the development of uterine balloon tamponade devices conceived to stop post-partum haemorrhages (PPHs). Design/methodology/approachThe phantom 3D model is generated by analysing the main requirements for validating uterine balloon tamponade devices. A modular approach is implemented to guarantee that the phantom allows testing these devices under multiple working conditions. Once finalised the design, the phantom effectiveness is validated experimentally. FindingsThe modular phantom allows performing the required measurements for testing the performance of devices designed to stop PPH. Social implicationsPPH is the leading obstetric cause of maternal death worldwide, mainly in low- and middle-income countries. The proposed phantom could speed up and optimise the design and validation of devices for PPH treatment, reducing the maternal mortality ratio. Originality/valueTo the best of the authors' knowledge, the 3D-printed phantom represents the first example of a modular, flexible and transparent uterus model. It can be used to validate and perform usability tests of medical devices