Each seminar highlights a different speaker who will discuss their latest research projects, cutting-edge technology or what is happening within certain technological industries. These industries include biomedical technologies or microsystems, assistive technologies, automation and intelligent systems, unmanned systems, advanced manufacturing and composite materials.
Topic:
Metrology-in-the-Loop Manufacturing: Layer-to-Layer Control of Additive Manufacturing
Abstract:
This talk will begin with an overview of manufacturing research at Missouri S&T, including an update on the Missouri Protoplex—a 110,000 sq. ft. facility featuring 40,000 sq. ft. of high-bay space designed to foster university–industry collaboration. The Protoplex is scheduled to open in Spring 2026. The technical focus of the presentation will be on metrology-in-the-loop (MITL) manufacturing—the direct integration of metrology into the manufacturing process to automatically adjust machine operation for process stabilization and performance improvement. The discussion will center on one application of MITL: achieving layer-to-layer stabilization in additive manufacturing, specifically within the blown-powder direct energy deposition (DED) process (also known as LENS). In DED, 3D parts are built layer by layer through the deposition of weld beads along a programmed path. Under certain conditions, parts may fail to build properly or develop propagating surface ripples. This talk will demonstrate how these failure modes can be understood by modeling the coupled layer-to-layer and in-layer dynamics of the process. Stability analysis techniques for the resulting multidimensional dynamic system will be used to identify failure modes, and a corresponding control framework will be developed to achieve stable layer growth. Experimental results will highlight the use of an in-process optical geometry scanner on a DED system to automatically detect and correct instabilities, enabling consistent part geometry. The presentation will conclude with examples of other MITL applications, including incremental sheet forming and robotic machining.
Biography:
Dr. Douglas A. Bristow is currently the William Walker III Professor in the Department of Mechanical and Aerospace Engineering at the Missouri University of Science and Technology (Missouri S&T). He received his B.S. in Mechanical Engineering from Missouri S&T in 2001, and his M.S. and Ph.D., also in Mechanical Engineering, from the University of Illinois at Urbana-Champaign in 2003 and 2007, respectively. Dr. Bristow is the Director of the Center for Aerospace Manufacturing Technologies, an industry consortium focused on developing and implementing next generation manufacturing technologies, primarily in additive manufacturing and robotic manufacturing. He has more than 100 peer-reviewed publications with more than 4000 citations. His research interests include precision motion control, iterative process control, and metrology-in-the-loop with applications in additive manufacturing, atomic force microscopy, machine tools, and robotic manufacturing. Dr. Bristow’s research is funded by the National Science Foundation, the Department of Energy, Manufacturing USA Institutes, and industry including Boeing, Bell Helicopter, GKN Aerospace, Toyota, Caterpillar, and DMG-Mori. In 2020 he received the ASME Rudolph Kalman Best Paper award for his work on modeling layer-to-layer dynamics in direct energy deposition.
Date:
Tuesday, November 11, 2025
Time:
10:00 a.m. (CST)
Location:
UTARI Auditorium
7300 Jack Newell Blvd. S, Fort Worth, Tx 76118
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