(Georgia Institute of Technology, 2018-04-27)
Garanger, Kevin
During the last decade, additive manufacturing (AM) has become increasingly popular for rapid prototyping, but has remained relatively marginal beyond the scope of prototyping when it comes to applications with tight tolerance specifications, such as in aerospace. Despite a strong desire to supplant many aerospace structures with printed builds, additive manufacturing has largely remained limited to prototyping, tooling, fixtures, and non-critical components. There are numerous fundamental challenges inherent to additive processing to be addressed before this promise is realized. One ubiquitous challenge across all AM motifs is to develop processing-property relationships through precise, in situ monitoring coupled with formal methods and feedback control. The goal of this thesis is to justify the relevance of closed-loop control in AM, and to pave the way for the creation of a general framework to formulate AM processes as control problems where feedback can be widely adopted. Two experiments of closed-loop control in additive manufacturing for the printing of specific parts are made. These experiments are a proof of concept that feedback control is feasible in AM even without precise physics models of the processes. From this point, a idea for the generalization of closed-loop control in AM is presented via the concept of semantics for AM files and the idea of adapting the local parameters of a printed object through topology optimization.