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Abstract This work presents a method for the topology optimization of welded frame structures to minimize the manufacturing cost. The structures considered here consist of assemblies of geometric primitives such as bars and plates that are common in welded frame construction. A geometry projection technique is used to map the primitives onto a continuous density field that is subsequently used to interpolate material properties. As in density-based topology optimization techniques, the ensuing ersatz material is used to perform the structural analysis on a fixed mesh, thereby circumventing the need for re-meshing upon design changes. The distinct advantage of the representation by geometric primitives is the ease of computation of the manufacturing cost in terms of the design parameters, while the geometry projection facilitates the analysis within a continuous design region. The proposed method is demonstrated via the manufacturing-cost-minimization subject to a displacement constraint of 2D bar, 3D bar, and plate structures.
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THE USE OF TOPOLOGY OPTIMIZATION IN ENHANCING THE STRUCTURAL PROPERTY OF AN AUTOMOTIVE FRONT SUB-FRAME
The frontal impact is the most common in automotive collision accidents, and bending the sub-frame can directly lead to severe passenger injury and property damage. This research analyzed the crashworthiness, design, mechanical integrity, and optimization of an automotive front sub-frame structure. From the original geometry, a new sub-frame with similar mass and mounting locations is designed. Loads were applied to the front side members of the sub-frame to simulate a common frontal and partial frontal crash. A sub-frame with enhanced structural efficiency was designed using topology optimization. This improvement may preserve the lifespan of the sub-frame, reinforce the protection of passengers and the engine, and improve crashworthiness. Topology optimization is a numerical analysis technique that allows engineers to distribute materials optimally for a specific cost function. Iterative update of design variables typically relies on sensitivity information from performance analysis in each step. A simple parametric study on material candidates and design constraints was executed to evaluate various design options. Sub-frames with optimized geometries were mechanically tested against two different simplified loads mimicking frontal crashes. The dynamic behaviors were also analyzed and compared to the original design for validation.
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- Award ID(s):
- 2107140
- PAR ID:
- 10350024
- Date Published:
- Journal Name:
- Zone 1 Conference of the American Society for Engineering Education
- ISSN:
- 2332-368X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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