SoCal Solids Conference 2023

Deep generative learning algorithms like the ones used in ChatGPT have had a profound impact on our lives. At some level their operation can be understood as generating samples from a conditional probability density function. That is, given a prompt, they generate samples of text that are consistent with, or conditioned on, the prompt. In this talk we will discover what role similar types of deep conditional generative algorithms which work with images instead of words, can play in solving problems in mechanics. In particular, we will consider conditional generative adversarial networks (cGANs) and conditional diffusion networks and describe how they can be used to solve complex probabilistic inverse/inference problems in mechanics.

The natural world is full of examples of materials with exquisite patterning and structuring on multiple length scales. These features often impart superior mechanical properties including high toughness and strength, and many biological materials are naturally stimuli responsive. Yet understanding how to controllably form and optimize such multiphase, hierarchical and adaptive materials remains a significant scientific and engineering challenge. Much of my group’s work focuses on developing new methods for the design, manufacture, and mechanical analysis of bioinspired material systems. Recent projects include the on-demand manufacture of lightweight composites, creation of light-activated, self-regulating actuators for use in soft robotics, as well as studies of the biological organisms themselves. In this talk, I will describe our recent work in developing 3D printing methods to create high performance polymer foams that can be manufactured on demand and have exceptional mechanical properties. Using a novel processing approach, we introduce controlled porosity through the incorporation of thermally expandable microspheres. We demonstrate how foaming impacts the mechanics of the composite material and show that the 3D-printed foams are remarkably resilient.

The principle of symmetry has served as a foundational element in the design and optimization of materials, influencing their mechanical, thermal, and electrical properties. Yet, breaking away from this convention by deliberately disrupting symmetry within materials can result in unexpected and interesting phenomenon. This talk will delve into the role of symmetry, and the implications when it is disrupted within architected material designs. First, we will explore the effects of this symmetry disruption within composite materials, bringing insights into unique fracture behaviors and enhanced defect tolerance. Second, we will investigate ordered and disordered cellular materials, balancing the classic conflict between strength and toughness. Lastly, we will discuss the influence of symmetry-breaking in piezoelectric metamaterials, where macroscopic momentum and electric stimuli form an unusual alliance, termed as 'electro-momentum coupling'. It is envisioned that our findings will provide new understandings for designing the next generation of materials, equipped with unprecedented properties and functionalities. We will also discuss potential future research directions and remaining challenges in this field.