James Guest

"Computational Design with Topology Optimization"

ABSTRACT -- This talk will discuss the use of topology optimization to improve designs in engineering applications, with a particular focus on design for manufacturability. Topology optimization combines optimization algorithms with physics-based modeling to generate optimized designs. This provides a systematic, mathematics-driven alternative to ad-hoc, intuition, and experience driven design approaches. Topology optimization has produced a number of designs which would have been difficult or impossible to arrive at in any other way. This includes mechanical components that provide exceptional levels of efficiency, mechanisms that deliver prescribed motion, and architected materials that are predicted to achieve theoretical bounds on specific stiffness. Other successes include multi-physics actuators, heat transfer topologies, light-trapping structures, and fluidic diodes.

With topology optimization, a designer specifies the desired performance functions to maximize (or minimize), minimum performance requirements, and applied loads and boundary conditions. For example, one can minimize the mass of an attachment bracket under multiple load cases with corresponding stiffness and stress limits. This optimization approach takes into consideration the materials available for use, as well as the manufacturing process. We will emphasize the incorporation of manufacturing into the optimization process, including design for additive manufacturing, including Fused Material Deposition (FMD), Selective Laser Sintering (SLS), fiber deposition, and NASA's Langley's Electron Beam FreeForm Fabrication (EBF3) technique, as well as subtractive approaches such as machining.

The capabilities of topology optimization are applicable to many flight projects. This lecture aims to spread knowledge of new computational engineering tools that can improve the missions we support.

SPEAKER -- Dr. James Guest is an associate professor in the Department of Civil and Systems Engineering at the Johns Hopkins University with a secondary appointment in the Department of Materials Science and Engineering. He leads the Topology Optimization Group at Johns Hopkins, which focuses exclusively on the development and application of topology optimization algorithms in design work. He also serves as the associate director of the Johns Hopkins Center for Additive Manufacturing and Architected Materials (JAM2).

Guest is secretary-general for the International Society for Structural and Multidisciplinary Optimization, and chair of the technical committee on Optimal Structural Design for the American Society of Civil Engineers (ASCE) Structural Engineering Institute. He also is a member of the Computational Mechanics Committee of the ASCE Engineering Mechanics Institute (EMI), and member of the Design Automation Committee of the American Society of Mechanical Engineers (ASME). The ASCE has awarded him their Walter L. Huber Civil Engineering Research Prize and their EMI Leonardo da Vinci Award.

Guest holds a bachelor's degree in Civil Engineering Systems from the University of Pennsylvania, and a PhD in Civil and Environmental Engineering from Princeton University.

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Engineering Colloquium home page: https://ecolloq.gsfc.nasa.gov