Archives—April 2011

Dr. Gregory Odegard Selected to Receive 2011 SAE Ralph R. Teetor Educational Award

Associate Professor Greg Odegard (ME-EM) has been named winner of a Society of Automotive Engineers (SAE) 2011 Ralph R. Teetor Educational Award. The national award recognizes top engineering educators.

“Your outstanding contributions have distinguished you as one of the top engineering educators,” the SAE said in its announcement.

The award, established by the SAE in 1965, recognizes outstanding engineering educators and enables them to meet and exchange views with practicing engineers in their fields. The award honors the late Ralph R. Teetor, 1936 SAE International president, who believed that engineering educators are the most effective link between engineering students and their future careers.

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Using Evolutionary Algorithms for Numerical Optimization of Spacecraft Trajectories

Thursday April 21, 2011 4:00-5:00 p.m.
ME-EM building, Room 112

Dr. Bruce A. Conway
University of Illinois-Urbana

There has been significant progress in the development of numerical methods for the determination of optimal trajectories for continuous dynamic systems, especially in the last 20 years. In the 1990s the principal contribution was new methods for discretizing the continuous system and converting the optimization problem into a nonlinear programming problem. This has been a successful approach that has yielded optimal trajectories for very sophisticated orbit transfer problems. In the last 10-15 years researchers have applied a qualitatively different approach, using evolutionary algorithms, to solving similar problems. Evolutionary algorithms use the principle of “survival of the fittest” applied to a population of individuals representing candidate solutions for the optimal trajectories. In this paper the advantages and disadvantages of these recently developed methods are described and an attempt is made to answer the question of what is now the best extant method.

April 2011 Senior Banquet and Order of the Engineer Induction

View the video of Williams’s address
View photos from the banquet

Keynote Speaker: Stephen L. Williams

Stephen L. Williams earned a BS degree in Mechanical Engineering from Michigan Tech in 1986. He went on to earn both an MS degree in Mechanical Engineering and an MBA from Wayne State University in Detroit, MI. After graduation from Michigan Tech, Steve began his career in his hometown of Cadillac, MI at Cadillac Rubber & Plastics as a Project Engineer.

In 1988 he moved to TRW Vehicle Safety Systems as a Project Engineer working on the first production airbag systems in many of Ford Motor Company’s vehicles. In 1990 he accepted a Project Engineering position at Chrysler Corporation in Vehicle Impact and Analysis. In 1992 he became Design Engineer responsible for all Jeep and Truck driver airbag systems, including the first production driver airbag system in a sport utility vehicle. From these assignments at Chrysler, Steve confirmed his true calling was in automotive engineering. For the next two decades he experienced a progressive ascension in responsibility at Chrysler. In 1994 he was promoted to Product Engineering Supervisor for all Jeep and Truck passive restraints and steering controls.

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Yielding of Solid Foams: An Energy Based Approach

Thursday April 14, 2011 4:00-5:00 p.m.
ME-EM building, Room 112

Dr. Murat Vural
Illinois Institute of Technology

Cellular solids such as solid foams and lattice truss structures draw a growing interest in engineering community mainly because of their lightweight. Reliable prediction of yield behavior in cellular solids is critical to the effective use of this class of highly porous materials in designing lightweight and potentially multifunctional structures in a multitude of engineering applications. Although there exist several yield criteria proposed in the literature for solid foams, they are all phenomenological in nature, rely on relatively long list of model parameters that require difficult experimentation not readily available to end user, and none of them can handle the anisotropy observed in commercially available solid foams. Furthermore, a rigorous validation of proposed models against experimental and/or computational data under complex stress states still remains to be a critical issue.

In this talk, a different approach is taken by hypothesizing that the yielding of stochastic foams is governed by the total elastic strain energy density. Based on an analytical framework developed around this hypothesis we propose a pressure-dependent yield criterion for transversely isotropic solid foams. Besides accommodating anisotropy this new energy-based yield criterion renders an advantage over various phenomenological relations proposed in literature by relying only on the elastic prope11ies and uniaxial yield strengths of the material. The results of an extensive finite element analysis and one-of-a-kind multiaxial experiments will be discussed to validate the proposed model and better understand the nature of pressure-dependency in deformation and yield behavior of solid foam s. It will be further shown that proposed analytical framework allows the introduction of new scalar measures of stress and strain (called characteristic stress and characteristic strain) that are capable of representing the elastic response of anisotropic foams with a single elastic master line under arbitrary multiaxial loading paths.

Dr. Sheryl Sorby Chosen to Receive the 2011 ASEE Sharon Keillar Award for Women in Engineering Education

The American Society for Engineering Education (ASEE) has honored Sheryl Sorby with its 2011 Sharon Keillor Award for Women in Engineering Education. Sorby is a professor of mechanical engineering at Michigan Technological University. The national award recognizes women who are making outstanding contributions to engineering education.

“Sheryl has made significant contributions to engineering education through her research on three-dimensional visualization skills,” said Michigan Tech College of Engineering Dean Tim Schulz. “I am pleased to see her receive this well-deserved recognition for her outstanding contributions to engineering education.”

Mechanical Engineering-Engineering Mechanics Chair Bill Predebon also praised Sorby, calling her “an educational innovator, which she has demonstrated through her research and throughout her career at Michigan Tech.”

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Broadband Mechanics of Structures Under Shock

Thursday April 7, 2011 4:00-5:00 p.m.
ME-EM building, Room 112

Dr. Jason Foley
Air Force Research Laboratory

The realm of impact and penetration presents a challenging set of environments for the design of shock survivable electromechanical systems. Survivable systems must be designed to withstand this harsh environment; intelligent survivable systems and their test instrumentation must also possess the capability to sense and interpret both internal and external dynamics during such events. This presentation explores the state of the art in shock experimentation, simulation, and analysis of these survivable systems.

The talk will begin with a brief survey of a few of the many outstanding research challenges in the world of shock mechanics. Next, the tools used in penetration and impact research will be discussed, with an emphasis on shock test methods and high bandwidth instrumentation (sensors and data acquisition). Results from some structural dynamics experiments are also discussed, with an emphasis on the role of interfaces in the nonlinear response of the systems under study. Two reduced-order computational approaches, wavelet- and Fourier-spectral element modeling, are presented that promise to increase the fidelity of impact/penetration simulations. Finally, new applications in broadband structural dynamics such as microsecond structural health monitoring and wavelet-based system analysis, will be examined. Gratuitous explosions are shown throughout the presentation.