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The genome inside the eukaryotic cells is guarded by a unique shell structure, called the nuclear envelope (NE), made of lipid membranes. This structure has an ultra torus topology with thousands of torus-shaped holes that imparts the structure a high flexural stiffness. Inspired from this biological design, here we present a novel “torene” architecture to design lightweight shell structures with ultra-stiffness for engineering applications. We perform finite element analyses on classic benchmark problems to investigate the mechanics of torene shells. This study reveals that the torene shells can achieve one order of magnitude or higher flexural stiffness than traditional shells with the same amount of material. This novel geometric strategy opens new avenues to exploit additive manufacturing to design lightweight shell structures for extreme mechanical environments.
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Topology Optimization of Lightweight Structures With Application to Bone Scaffolds and 3D Printed Shoes for Diabetics
Abstract An automatic complex topology lightweight structure generation method (ACTLSGM) is presented to automatically generate 3D models of lightweight truss structures with a boundary surface of any shape. The core idea of the ACTLSGM is to use the PIMesh, a mesh generation algorithm developed by the authors, to generate node distributions inside the object representing the boundary surface of the target complex topology structures; raw lightweight truss structures are then generated based on the node distributions; the resulting lightweight truss structure is then created by adjusting the radius of the raw truss structures using an optimization algorithm based on finite element truss analysis. The finite element analysis-based optimization algorithm can ensure that the resulting structures satisfy the design requirements on stress distributions or stiffness. Three demos, including a lightweight structure for a cantilever beam, a femur bone scaffold, and a 3D shoe sole model with adaptive stiffness, can be used to adjust foot pressure distributions for patients with diabetic foot problems and are generated to demonstrate the performance of the ACTLSGM. The ACTLSGM is not limited to generating 3D models of medical devices, but can be applied in many other fields, including 3D printing infills and other fields where customized lightweight structures are required.
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- Award ID(s):
- 1952873
- PAR ID:
- 10352613
- Date Published:
- Journal Name:
- Journal of Applied Mechanics
- Volume:
- 89
- Issue:
- 4
- ISSN:
- 0021-8936
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4053396
