Additive manufacturing has enabled the creation of new classes of architected meta-materials with exceptional structural and functional properties. Large-area projection micro-stereolithography (LAPµSL) has the potential for producing large volume metamaterials with millions of micro-scale unit cells and multiple orders of magnitude in length scales. Nevertheless, as part size grows with increasing number of unit cells, probability of finding embedded defects becomes significantly higher. Structural defects, such as internal cracks and non-uniformity embedded within networks of micro-scale...
BSAC is pleased to announce the outstanding paper and presentation award recipients from the Fall 2024 Research Review on September 18th. The Industrial Advisory Board was highly impressed by the quality of research, and the recipients’ work stood out in a competitive field.
We sincerely thank all the researchers who presented their innovative projects. These contributions are key to advancing research and fostering collaboration between academia and industry.
After careful evaluation, BSAC Industrial Members have voted, and we congratulate the Fall 2024 Best of BSAC honorees...
The rapid development of additive manufacturing technologies has enabled the fabrication of truss metamaterials, i.e., a novel class of lightweight-yet-strong materials with engineered complex hierarchical structures. Manipulating the architecture over chemical composition dramatically expands the achievable materials design space, allowing to largely control the mechanical response of metamaterials. Despite the great advances made in this area, designing three-dimensional (3D) truss metamaterials under complex or extreme conditions with programmable response is still a...
The orientation of fibrous fillers, induced by shear forces during extrusion, has been demonstrated to significantly enhance mechanical properties, electrical/thermal conductivity, microwave attenuation etc., albeit primarily in a two-dimensional (2D) x-y plane. In this study, we present a novel approach for achieving fiber alignment in a three-dimensional (3D) context, with an emphasis on the Z-direction, by utilizing embedded 3D printing techniques. This process involves the extrusion and suspension of composite inks within a viscoelastic gel medium, during which the...
This project seeks to additively manufacture micro-architected cellular solids in high resolution, large area in hundreds of millimeters, containing millions of unit cells which are defect-free.
David Hahn is currently pursuing a PhD program in Mechanical Engineering at UC Berkeley. Prior to joining UC Berkeley, he was a Mechanical Design Engineer at OFS (Optical Fiber Solutions) FITEL in Atlanta, GA. He received BS and MS in Mechanical Engineering from Georgia Tech.
Engineered composites with fiber orientation in a complete three-dimensional (3D) context are highly desired for maximizing structural performance as they mimic the well-organized fiber arrangement in natural composites. However, most fabrication techniques lack the capability for through-plane (z-axis) alignment, limiting the possibility for structural design and performance optimization. In this study, we present an embedded 3D printing approach that enables complete 3D fiber alignment, including region-specific alignment control along the through-plane direction. Our method utilizes the...
AI-driven framework creates defect-tolerant materials with complex functionality July 22, 2025 by Marni Ellery| Article Published in UC Berkeley Engineering
Many industrial products — from car bumpers to aerospace panels and medical implants — owe their performance to lightweight, cellular materials. These hard-working synthetics are engineered to meet specific functionality goals, but too often, defects introduced during the fabrication process can lead to subpar performance or even catastrophic failure.
Now, a UC Berkeley-led team of researchers has developed a new AI-driven...
