AME Seminar: Kavan Hazeli and Hossein Rastgoftar
The Department of Aerospace & Mechanical Engineering Seminar Series
Professor Kavan Hazeli
"Multifunctional Additively Manufactured Lattice Structures: Potential, Design, and Mechanics"
Assistant Professor Hossein Rastgoftar
"Continuum Deformation Approaches to Large Scale UAS Coordination and Traffic Management"
Thursday, August 26th at 4:00 pm
AME Lecture Hall, Room S212
Contact eperumala@arizona.edu for details.
Kavan Hazeli
Abstract: Manufacturing multifunctional metals through the structural hierarchy (e.g., additively manufactured lattice structures or AMLS) is foreseen as one of the most promising directions of additive manufacturing (AM) as it can overcome the limitations of physical and mechanical properties of solid metallic materials that are imposed by the nature of their crystalline structure. AM techniques have revolutionized the manufacturing aspect of lattice structure materials by enabling a design that captures multiple functions through an intricate and complex structural hierarchy. Empty spaces within AMLS enable controlled heat transfer, shock and vibration energy management. Furthermore, the potential of integrating sensors allows the use of AMLS in more novel ways than a multifunctional structural component alone. On-board, sensors enable real-time health monitoring, data transfer, and failure analysis. Since a wide range of topology (CAD file) and microstructure could be built during the build process by using laser input parameters or by heat treatment, therefore, the design space of AMLS is overwhelming. This presentation focuses on how to narrow down the design space while accounting for microstructure and topology that works efficiently for a specific loading condition.
Bio: Dr. Hazeli received his Ph.D. degree from the Mechanical Engineering and Mechanics Department at Drexel University in 2014. He completed his postdoctoral training in the summer of 2016 at Hopkins Extreme Materials Institute at Johns Hopkins University. His research lies at the intersection of manufacturing, materials science, and mechanics. Specifically, he uses combined experimental and modeling techniques to design multifunctional materials for complex loading conditions relevant to defense and biomedical applications. Dr. Hazeli is a recipient of the 2020 National Science Foundation CAREER Award.
Hossein Rastgoftar
Abstract: This presentation discusses continuum deformation modeling of coordination of a large number of aerial vehicles treated as particles of deformable bodies (or continuum). Assuming desired coordination of an unmanned aerial system (UAS) team is the solution of the Laplace equation, Lagrangian and Eulerian continuum mechanics will be applied to safely plan UAS coordination in finite airspace. The Lagrangian continuum mechanics is used to manage the large-scale coordination of a UAS team in a cluttered environment when the total number of agents is fixed. In this context, we optimize a large-scale continuum deformation coordination, and formally specify and verify collision-free collective motion with minimal communication and computation overhead, enabling distance between individual UAVs to significantly change while assuring the vehicles do not collide. Furthermore, the Eulerian continuum mechanics can be applied to achieve freely scalable coordination and manage traffic coordination in finite airspace. Using the Eulerian description of continuum mechanics, the space and time allocated to an individual UAS can be effectively managed and the airspace capacity can be maximized through controlling UAS inflow and outflow at the airspace boundaries with minimum computation overhead. In particular, the airspace can be classified into planned and unplanned spaces by dynamically updating planned-unplanned airspace boundaries while nominal coordination is obtained as the solution of a governing PDE with spatiotemporal cyber-physical parameters.
Bio: Dr. Hossein Rastgoftar is currently an assistant professor in the Aerospace and Mechanical Engineering Department at the University of Arizona. Prior to this, he was an assistant professor of Mechanical Engineering at Villanova University and an adjunct assistant professor at the University of Michigan from 2020 to 2021. He was also an assistant research scientist (2017 to 2020) and a postdoctoral researcher (2015 to 2017) in the Aerospace Engineering Department at the University of Michigan. He received his Ph.D. in Mechanical Engineering from Drexel University in 2015 and has two MS degrees (one in Mechanical Systems and the other in Solid Mechanics) and a BS degree in Mechanical Engineering-Thermo-Fluids. Rastgoftar’s areas of interest span decision-making under uncertainty, human-robotic interaction, swarm robotics, system autonomy, UAS traffic management, intelligent transportation, formal specification and verification, and finite-state abstraction of dynamical systems. He is the sole author of the book “Continuum Deformation of Multi-Agent System” published by Springer (https://www.springer.com/gp/book/9783319415932).