Medical Engineering Thesis Defense, Weiting Deng
Natural cellular biomaterials typically consist of hard and soft constituent materials that are hierarchically ordered to achieve outstanding mechanical properties, e.g., light weight, mechanical resilience, multi-functionality, etc. Architected materials are a new class of engineered materials with meticulously controlled internal structures that produce properties that differ from or exceed those of their constituent materials. Recent developments in additive manufacturing offer an extraordinary opportunity to rationally design the structure and chemical composition of architected materials to optimize properties and functionalities for a wide range of device applications. Here we first present a framework that combines an artificial intelligence tool and two-photon lithography in order to design and fabricate optimal porous structure with the desired anisotropic mechanical properties. The biomimetic and extremely tunable natural of the structures generated by the framework enables the great potential to be used as the bone scaffold design strategy which meets the requirements of complex anisotropic and heterogeneous mechanical properties of the vivo environment. The designed the architectures are meticulously verified by in situ Nanomechanics. These theory-informed experiments revealed close agreement between experimental data and artificial intelligence-predicted stiffness anisotropy, which opens a pathway for uncovering previous unattainable design space of elasticity vs. 3D architecture mapping in quantifiable and deterministic way. Besides, we explore the structural and material effects of additively manufactured microrobots which is powered by external physical fields for complex therapeutic assignments. The excellent movability and controllability permit the microrobots to be used as minimal invasive instruments for precise application in healthcare. The synergistically optimized microstructures and chemical composition enables the microrobots great potential to be applied to in vivo clinical applications.