Category: Research Features

Challenging Structure: $15M US-COMP Now in Year Five

Professor Greg Odegard is the John O. Hallquist Endowed Chair in Computational Mechanics, Mechanical Engineering-Engineering Mechanics, Michigan Tech

Leading the charge in developing a new lighter, stronger, tougher polymer composite for human deep space exploration, the Ultra-Strong Composites by Computational Design (US-COMP) institute under the direction of Dr. Greg Odegard has pivoted with agility during their final year of a five-year project. 

The NASA-funded research project brings together academia and industry partners with a range of expertise in molecular modeling,manufacturing, material synthesis, and testing.

“When we began developing these ultra-strong composites, we weren’t sure of the best starting fibers and polymers, but over time we started to realize certain nanotubes and resins consistently outperformed others,” says Odegard. “Through this period of development, we realized what our critical path to maximize performance would be, and decided to focus only on that, rather than explore the full range of possibilities.”

In the past year, the group improved performance using carbon nanotube yarns, which not only can be seen with the naked eye, but can also be held and touched. “We have looked at carbon nanotube socks, sheets, and pulps, but last year saw the most promise in the yarn form that our partner company is producing,” he says.

US-COMP PARTNERS

  • Florida A&M University
  • Florida State University
  • Georgia Institute of Technology
  • Massachusetts Institute of Technology
  • Pennsylvania State University
  • University of Colorado
  • University of Minnesota
  • University of Utah
  • Virginia Commonwealth University
  • Nanocomp Technologies
  • Solvay
  • US Air Force Research Lab

For the past 21 years, scientists around the world have invested time, money, and effort to understand carbon nanotubes. But the islands of knowledge remain isolated in a vast sea of unknown behavior.

“When we started the project, we were confident we were going to put effort into getting the polymers to work well. The last thing we expected was the need to focus so much on the carbon nanotubes—but we’ll also put effort in how to make the nanotube yarn stronger using modeling and experimental methods,” Odegard notes.

“Our partners at Florida State are manufacturing the panels that we make from the carbon nanotube yarns and the polymers and then they are shipped to the University of Utah for testing. During the testing, the panels are cut up and tested, then the results are shared back with the full institute.”

The challenge when working with carbon nanotubes is their structure. “Under the most powerful optical microscope you see a certain structure, but when you look under an SEM microscope you see a completely different structure,” Odegard explains. “In order to understand how to build the best composite panel, we have to understand everything at each length scale.” 

The US COMP Institute has created dedicated experiments and computational models for the chosen carbon nanotube yarn structure at each length scale. “We can all see the different parts in our sub-groups and then we communicate that to the rest of the team, building a more complete picture from the little pictures at the individual scales,” he says. “We found the hierarchical modeling approach is hard to make work and what works best is a concurrent approach. We each answer questions at our own length scales, feed our findings to manufacturing, and then see how they in turn tweak the processing parameters.”

“We’ve achieved a remarkable workflow and a new model for collaboration.”

—Michigan Tech ME-EM Professor Greg Odegard

Achieving their Year Four goal to understand the internal structure of the carbon nanotube yarns, the institute has shifted focus to surface behaviors. As part of the project, they are tasked with bringing the carbon nanotube yarn together with the final selected polymer.

“We are looking at the surface treatment of the yarn and how to get it to best work with the polymer of choice. We are excited to expand our scope of machine learning methods to better understand the yarn, accelerating our understanding of how processing parameters impact the structure and how that ultimately impacts the bulk material properties.”

While machine learning has been part of the project scope from the beginning, the computational team is using their collected data to build a series of training sets. “The training sets will allow us to perfect our algorithms, learn from them, and hopefully influence product performance—potentially illuminating patterns we didn’t even see,” Odegard explains.

As the project draws to a close this year, the team continues to analyze their objectives set by NASA, which focus on producing a material that offers triple the strength and stiffness of the current state-of-the-art. As Odegard puts it, “The objectives set on this project are difficult to achieve. We knew that when we started. Regardless of whether we meet the numbers, as a group we have been able to push the envelope way beyond where we started in 2017—expanding the performance in a very short time period. This was made possible through remarkable collaboration across the institute.”


Tiny Nanoindentations Make a Big Difference for Prasad Soman

microphoto of nanoindentations seen near the grain boundary of iron, seen at 20 microns
Nanoindentations performed near or away from the grain boundary of iron, made to study their effect on deformation. Photo credit: Prasad Soman

Prasad Soman will graduate soon with his MSE PhD. But instead of walking down the aisle and tossing his cap in Michigan Tech’s Dee Stadium, this year he’ll take part in Michigan Tech’s first-ever outdoor graduation walk.

“My PhD research goal was to better understand how the addition of carbon affects the strengthening mechanism of iron—by looking to see what happens at the nanoscale,” he explains.

Soman studied the mechanisms of grain boundary strengthening by using an advanced and challenging technique known as nanoindentation to get “up close and personal” to the interfaces between individual crystals within a material. Just last week Soman successfully defended his PhD dissertation: “Study of Effects of Chemistry and Grain Boundary Geometry on Materials Failure.” The research was sponsored by the US Department of Energy.

photo of Prasad Soman
“My experience at Tech has been exciting and fulfilling: study, teaching, and research amidst the beauty of the Upper Peninsula of Michigan,” says Prasad Soman, who will graduate from Michigan Tech on April 30 with a PhD in Materials Science and Engineering.

He’ll soon be moving to California to take a position with Amazon, the culmination of many years of hard work. “My journey into the field of metallurgy and materials science began in India, way back in high school, when I was thinking of choosing a major for my undergraduate studies in engineering. I had developed a great interest in Physics and Chemistry, then discovered I could pursue my interest even further by choosing metallurgical engineering as my major,” he says. Though his new position will not utilize his metallurgical expertise in a direct way, Amazon was drawn to Prasad’s ability to independently carry out and complete a detailed research project that required a high level of attention to detail, data collection, and advanced analysis and physical modeling.

“I attended College of Engineering Pune, one of the top tier schools for metallurgy in India. Upon graduation, I went on to work in the steel industry for a while, and then decided to pursue higher education in the US.

Soman arrived at Michigan Tech with the intention of earning a Master’s in MSE. Professor Yun Hang Hu advised Soman towards that degree, involving him in research focused on the fabrication and characterization of Molybdenum Disulfide (MoS2)-based electrodes (aka Moly) for supercapacitor applications. The experience prompted Soman to continue on in his studies and earn a PhD.

For his MS degree, Soman worked with Yun Hang Hu, Charles and Carroll McArthur Professor of MSE at Michigan Tech

Two MSE faculty members, Assistant Professor Erik Herbert and Professor Stephen Hackney, served as Soman’s PhD co-advisors. “Prasad analyzed the effect of grain boundary segregation on the strengthening and deformation mechanism in metals and alloys,” says Herbert. “To do this Prasad intensively used small-scale mechanical testing, including nanoindentation and in-situ TEM experiments.”

“The most exciting part of this work involved utilizing various material characterization techniques,” says Soman. “The Advanced Chemical and Morphological Analysis Laboratory (ACMAL) facility, located in the Michigan Tech M&M building near the MSE department, is one of the best materials characterization facilities in the world. Characterization of the materials response to mechanical indentation was essential for my PhD work, so having access to the many techniques available in ACMAL was both revealing and fulfilling.”

‘The work was painstaking, but thanks to Prasad’s incredible hard work, skill, and dedication, he was able to make significant inroads to improve our understanding.” 

Dr. Erik Herbert, Assistant Professor, Materials Science & Engineering

Soman used a variety of characterization methods in his research, including nanoindentation, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscatter diffraction spectroscopy (EBSD). “All help examine materials behavior at the nanometer scale,” he adds.

In particular, Soman used nanoindentation to study local grain boundary deformation in metals and alloys. “Using nanoindentation we can measure hardness at a very small length scale. The indentation impression size is on the order of a couple of microns—smaller than the width of a human hair,” Soman explains.

Two MSE faculty members, Professor Stephen Hackney (l) and Assistant Professor Erik Herbert (r) served as Soman’s PhD co-advisors.

“Performing a nanoindentation was challenging at first. The goal is to get the indentation very close to the grain boundary. The task is done using a simple optical microscope, yet accuracy on the order of a couple of microns must be achieved. That kind of accuracy is essential for the proper positioning of the indent relative to the boundary. But just as for any other thing, the more you practice (and learn from mistakes) the better you perform. It’s been a great achievement for me to consistently get the indentation accurately placed.”

PhD Candidate Prasad Soman hard at work in Michigan Tech’s ACMAL Lab

“Instrumented indentation experiments allow us to measure materials properties—including hardness and elastic modulus—as a function of depth,” says Soman. “We also examine how different microstructural features—grain boundary vs. grain interior—respond to a very localized deformation at nanometers length scale.”

Soman says he decided to join Michigan Tech’s MSE program due to its strong emphasis on metallurgical engineering. “While here at Tech, however, I was exposed to a variety of domains within materials science—energy storage materials, semiconductors, polymers, and more. So, while I focused on my passion for fundamental science in metallurgy, I also developed understanding and skills in these different domains,” he explains.

“That has come to fruition, as I will now be going to work in the consumer electronics industry, which requires a multidisciplinary approach.”

The large building on the far left of this campus photo is Michigan Tech’s Mineral and Materials Engineering Building (aka the “M&M”)—home to the MSE Department and the Advanced Chemical and Morphological Analysis Laboratory (ACMAL).

Soman will soon pack up and move to Sunnyvale, California. He’ll be working as a hardware development engineer at Amazon. “The team is a cool group of engineers/scientists with diverse backgrounds—mechanical, chemical, design and other disciplines, as well. We’ll develop health and wellness electronic devices, such as smart watches, smart AR/VR glasses, and more. This job will allow me to utilize some of the key skills I developed at Michigan Tech in the field of metallurgy and mechanics. More than anything, I am eager to learn from the best of the best—all the folks in my team.”

One last thing, adds Soman: “I will terribly miss Houghton. I call it my home away from home.”


Paleomagnetism: Deciphering the Early History of the Earth

Rock samples in Smirnov’s lab are 2-3 billion years old.

Although it makes up about seven-eighths of the Earth’s history, the Precambrian time period is far from figured out. Key questions remain unanswered.

The Precambrian—the first four billion years of Earth history—was a time of many critical transitions in Earth systems, including oxygenation of the atmosphere and emergence of life. But many of these processes, and the links between them, are poorly understood.

Data can be obtained from fossil magnetism—some rocks record the Earth’s magnetic field that existed at the time of their formation. However, for very old rocks (billions of years old) the conventional methods of obtaining fossil magnetism do not work well.

Professor Aleksey Smirnov, Chair of the Department of Geological and Mining Engineering and Sciences

Michigan Tech Professor of Geophysics, Aleksey Smirnov, seeks to substantially increase the amount of reliable data on the Precambrian field. Smirnov investigates the fossil magnetism of well-dated igneous rocks from around the globe using new and experimental processes to help fill in the blanks. His work on the early magnetic field history is supported by several National Science Foundation grants including a National Science Foundation CAREER award.

“Deciphering the early history of our planet, the early history of its geomagnetic field, represents one of the great challenges in Earth science,” says Smirnov. “Available data are scarce, and key questions remain unanswered. For instance we still don’t know how and when the Earth’s geomagnetic field began.”

Smirnov and former student Danford Moore
drill rock samples in the Zebra Hill region, Pilbara Craton, Western Australia.

“How did the geomagnetic field evolve at early stages? How did it interact with the biosphere, and other Earth system components—these are all largely unanswered questions. There is also disagreement on the age of the solid inner core, ranging between 0.5 and 2.5 billion years,” note Smirnov.

Scientists largely believe the Earth’s intrinsic magnetic field is generated and maintained by convective flow in the Earth’s fluid outer core, called the geodynamo.

Smirnov’s research has broad implications for Earth science including a better understanding of the workings and age of the geodynamo.

Earth cutaway. Credit: Lawrence Livermore Lab

“Crystallization of the inner core may have resulted in a dramatic increase of the geomagnetic field strength preceded by a period of an unusually weak and unstable field,” he explains. “If we observe this behavior in the paleomagnetic record, we will have a much better estimate of the inner core age and hence a better constrained thermal history of our planet.”

Knowing the strength and stability of the early geomagnetic field is also crucial to understanding the causative links between the magnetic field and modulating the evolution of atmosphere and biosphere,” notes Smirnov.

An illustration of the Earth’s magnetic field. Credit NASA.

Today, the Earth’s magnetic field protects the atmosphere and life from solar and cosmic radiation. “Before the inner core formation, the geodynamo could have produced a much weaker and less stable magnetic field. An attendant weaker magnetic shielding would allow a much stronger effect of solar radiation on life evolution and atmospheric chemistry.”

Both graduate and undergraduate students work with Smirnov to conduct research, logging hours in his Earth and Environmental Magnetism Lab, traveling the world to collect specimens.

The Earth and Environmental Magnetism Lab at Michigan Tech: If you drop a metal object on the floor there, the shielding properties of the room can be lost.

“The primary (useful) magnetizations recorded by ancient rocks are usually very weak and are often superimposed by later (parasitic, secondary) magnetizations,” Smirnov explains. “In order to get to the primary magnetization, we have to remove the secondary magnetizations by incremental heatings of the samples in our specialized paleomagnetic furnaces. The heatings must be done in a zero magnetic field environment. This is one reason why we have the shielded room, which was specially built for our paleomagnetic lab. There are other shielded rooms around the country, but ours is the only one at Michigan Tech,” he notes.

“The second reason for having our instruments in the shielded room is that the magnetizations we measure are weak and our instruments are so sensitive that the Earth’s magnetic field can interfere with our measurements. In fact, in addition to the shielded room, each instrument inside has an additional magnetic shielding.”

Note that the shielded room was built before I came, by my predecessors Profs Jimmy Diehl and Sue Beske-Diehl.

Students in this photo (some now graduates) are performing liquid helium transfer into one of our cryogenic magnetometers. “We need to constantly keep the sensors at a very cold temperature (only a very few degrees above the absolute zero temperature) to provide their ultra-sensitivity,” says GMES professor and chair, Aleksey Smirnov. “It is based on the principle of superconductivity.”

On one month-long trip to the Pilbara Craton in northwest Western Australia, Smirnov and a student gathered 900 samples of well preserved, 2.7 to 3.5 billion year old Precambrian rocks. 

Smirnov stepped into the role of chair of the Department of Geological and Mining Engineering and Sciences last fall, but that won’t keep him too far from his research. “Any interested student should feel free to get in touch to learn more about research positions,” he says.

Investigations in Smirnov’s lab are not limited to the ancient field. Other interests include the application of magnetic methods for hydrocarbon exploration, magnetic mineralogy, magnetism of meteorites, biomagnetism, and plate tectonics.

Learn more

Aleksey Smirnov is the new Chair of Geological and Mining Engineering and Sciences

Clues To Earth’s Ancient Core


Sarah Sun: Nice shirt! Embroidered Electronics and Motion-Powered Devices

A prototype of a flexible electronic circuit. Stitch schematics such as this one can be used to create health-monitoring fabrics.

Sarah Sun shares her knowledge on Husky Bites, a free, interactive webinar this Monday, September 28 at 6 pm ET. Learn something new in just 20 minutes, with time after for Q&A! Get the full scoop and register at mtu.edu/huskybites.

What if your medical heart monitor was embroidered right on your shirt, in your favorite design? And what if it was powered by your own movements (no battery required)? And what if you could even design and order it yourself, right on the internet? Get ready to learn all about this, and more.

Join Dean Janet Callahan for supper along with Sarah Sun, an associate professor of mechanical engineering, and George Ochieze, a graduate student researcher in Dr. Sun’s Human-Centered Monitoring Lab at Michigan Tech.

Associate Professor Sarah Sun

Sun is the lead investigator of three National Science Foundation research grants totaling $1 million focused on wearable electronics. She is also the director of the Center for Cyber-Physical Systems within Michigan Tech’s Institute of Computing and Cybersytems ICC.

“I am passionate about using engineering solutions to solve health problems,” she says. “We’re trying to solve long-existing technical challenges to improve medical devices, and we’re developing new technologies, too, in order to enable more diagnosis solutions.”

One of Sun’s large research projects involves developing new human interfaces for monitoring medical vital signs.

Their goal: to provide a reliable, personalized monitoring system that won’t disturb a patient’s life, whether at home, while driving, or at work. “Right now for patients there’s a real trade-off between comfort and signal accuracy. This tradeoff can interfere with patient care and outcomes, too,” she explains.

Sun hopes to use electrophysiological sensing and motion sensing to help prevent automobile crashes, especially those that occur when drivers accidentally fall asleep at the wheel. According to the National Highway Traffic Safety Administration, while the precise number can be hard to nail down, drowsy driving is a factor in more than 100,000 crashes in the U.S each year, resulting in nearly 1,000 deaths and 50,000 injuries.

First, though, Sun and her team needed to figure out how to overcome a major challenge in monitoring vital signs: motion artifacts, or glitches caused by the slightest patient movement, even shivering, or tremors.

Motion artifacts appear in an ECG when the patient moves.

“ECG, a physiological signal, is the gold standard for diagnosis and treatment of heart disease, but it is a weak signal,” Sun explains. “Especially when monitoring a weak signal, motion artifacts arise.”

Sun and her team first set out to discover the mechanism underlying the phenomenon of motion artifacts. Then, they realized they were able to tap into it. 

“We not only reduce the influence of motion artifacts but also use it as a power resource,” she says. The result: a sensing device that harvests energy from patient movements.

Sun cites recent progress in the development and manufacturing of smart fabrics, textiles, and garments. “This has opened the door for next-generation wearable electronics—fully flexible systems that can be embroidered directly onto cloth,” she says.

“Feel free to download our .exp files for your own wearable system on cloth manufacturing. The code can be processed by regular sewing machines. Just go online to WEF, our new Wearable Electronics Factory.

Sarah Sun, Mechanical Engineering Assoc. Professor at Michigan Tech

By using conductive thread and passive electronics—tiny semiconductors, resistors and capacitors—Sun is able to turn logos into wearable electronics. The stitches themselves become the electronic circuit. Sun and her team can embroider on just about anything flexible, including cloth, foam, and other materials. 

Sun is also building a manufacturing network and cloud-based website where stitch generation orders can be made. “In the future, a person can upload their embroidery design to generate stitches, or download certain stitches as needed,” she says. The lab provides coding for the electronics and stitch generation to embroiderers. “Soon any embroidery company will have the potential to manufacture embroidered health monitors,” she says.

These wearable, embroidered ”E-logos” can monitor multiple vital signals. They’re customizable, too. 

Sun hopes flexible, wearable electronics will interest a new generation of engineers by appealing to their artistic sides. “This type of embroidery circuit really brings together together craft and functional design.” 

Mechanical Engineering PhD student George Ochieze arrived on campus at Michigan Tech in 2019. He grew up in Abia, Nigeria and earned his bachelor of engineering at Federal University of Technology Owerri in 2017.

George Ochieze is pursuing a master’s degree in Mechatronics and a PhD in Mechanical Engineering. He took Sun’s Introduction to Mechatronics and Robotics course at Michigan Tech last spring. That’s when he discovered his own passion: working with machines and control devices. He joined her research group last summer.

Mechatronics uses electromechanical systems automated for the design of products and processes,” Ochieze explains. “I picked up my research interest after modeling an RRR manipulator using CAD software. That’s a robot manipulator set up with 3 revolute joints. I had some challenges in controlling the joints, and Dr. Sun gave me some tips. She was very helpful in guiding me through the process, and our mentor/mentee relationship in soft robotics was formed,” says Ochieze.

Soft Robotics involves the design and construction of robots from flexible, compliant materials, drawing from the movements and adaptations of living organisms. Soft robots offer new capabilities, as well as improved safety when working around humans, with potential use in medicine and manufacturing.

Ochieze plans to share a demo on soft robotics during Husky Bites.

“Throughout my growth in the engineering field, I have been surrounded by people who are generous enough to share their knowledge. I look forward to mentoring others like me within this field.”


Professor Sun, when did you first get into engineering? What sparked your interest?

My dad liked to play with old electronics when I was young. I built my first radio receiver in middle school with him although I did not know how those electronics work at that time. This experience really inspired my interest in pursuing an engineering degree. I earned my bachelor’s degree at Tianjin University. It’s located near Beijing, in Tianjin, China, on the Bohai Sea. About six year ago, I earned my PhD in electrical engineering at Case Western Reserve University in Cleveland, Ohio. My doctoral research was on wearable electronics.

Family and Hobbies?

I grew up in Northern China, in a town with a very cold winter climate, but dry. My husband came to Michigan Tech first. He liked the U.P. a lot and told me lots of great things about Tech.  It was challenging for me to balance work and life at first, especially with two little kids. My son, Brent, is almost 8 now, and my daughter, Leah, is two. My husband and I both like to design and build stuff, so we enjoy it with our kids, too. 

George, how did you first get into engineering? What sparked your interest?

I grew up in Aba, in Abia, Nigeria. Working in my Dad’s fabrication company fostered my interest in the engineering field. At a young age I became familiar with machine operations. I was fascinated with the sequence operation of machines to achieve a desired goal. I started developing cars and movable structures with available materials, leading my fellow students in the design of mechanical components.

Graduate student George Ochieze in the Human-Centered Monitoring Lab at Michigan Tech. His passion and research focus: soft robotics.


Do you do any mentoring or teaching on campus?

I am one of two instructors in Michigan Tech’s Career and Technical Education (CTE) Mechatronics program for local high school juniors and seniors. Even in difficult times during the pandemic, these young scholars show overwhelming potential to conquer the mechatronics field—a glimpse into a welcoming future in engineering. They will go on to find degree pathways at Michigan Tech, and excellent careers in smart manufacturing.

Read and View More

Vital signs—Powering Heart Monitors with Motion Artifacts

Ye Sun Wins CAREER Award

Human Centered Monitoring Laboratory (HCML)

Stitches into Circuits (check out the video, below)



Chad Deering: Predicting Volcanic Unrest Via Plant Life Stress

Vegetative stress at the foot of the Kīlauea Volcano in Hawaii

After a volcanic eruption, it can take years for vegetation to recover, and landscapes are often forever changed. But well before any eruption takes place, the assemblage of plant species on and around the volcano show signs of stress, or even die off. 

Chad Deering

Chad Deering, a volcanologist in the Department of Geological and Mining Engineering and Sciences at Michigan Technological University uses hyperspectral remote sensing data, acquired during an airborne campaign over Hawaii, to predict future volcanic eruptions on the Big Island. Deering and his team of graduate students from Michigan Tech are collaborating with scientists from the NASA Jet Propulsion Laboratory (JPL), and the University of New Mexico. 

“The replenishment of a shallow magma reservoir can signal the onset of an eruption at a dormant volcanic system, such as at Mauna Loa. It can also indicate significant changes in eruptive behavior at an already active volcano, as in what occurred at Kīlauea,” Deering says. 

“Rising magma ultimately results in a flux of volatiles through the ground, including carbon dioxide and sulfur dioxide. Active vent plumes of those same gases include particulate matter, even thermal energy, and those often enter the atmosphere, as well. “

By detecting and characterizing those fluxes and their effects on the health and extent of local vegetation, Deering is able to recognize significant changes in a volcano’s behavior. The result: a new, cost-effective way to forecast volcanic hazards and events.

“Monitoring vegetative stress on a volcano can potentially provide a much-needed early warning system for those living near and around volcanoes,” adds Deering. An estimated 500 million people are living in danger zones around the world.

“Our preliminary results indicate a strong correlation between emissions of carbon dioxide and hydrogen sulfide gas from soil—as well as the thermal anomalies—and different aspects of vegetative stress.” 

Deering’s team uses highly sensitive hyperspectral analysis to distinguish between effects of different gas species and thermal anomalies on variations in vegetative stress. “This is important as CO2 and H2S have different solubilities in magma. That allows us a semi-quantitative measure of the depth of magma as it rises.

With the results of their study, the team developed a remote-sensing automated detection algorithm that can be used in satellite-based platforms to detect volcanic unrest at volcanoes worldwide. 

“In particular, this tool will allow the scientific community to monitor volcanoes that are otherwise inaccessible due to heavy vegetation and/or their remote locations,” adds Deering. “It will also remove technical barriers such as establishing extensive and expensive seismic arrays that are difficult to maintain.”

NASA gathered the hyperspectral data over the course of a year, starting in 2017. Deering and his team are now analyzing more recent data, collected last year. “We want to determine whether we could have predicted the recent volcanic fissure emergence and activity taking place in Hawaii.”


Biofuels and Dry Spells: Switchgrass Changes During a Drought

High yields. A deep root system that prevents soil erosion and allows for minimal irrigation. The ability to pull large amounts of carbon out of the air and sequester it in the soil. Beneficial effects on wildlife, pollination, and water quality. Perennial grasses, such as switchgrass and elephant grass, are wonderful in many ways and especially promising biofuel feedstocks. But that promise, a team of researchers discovered, may evaporate during a drought.

“The characteristics of any living organism are linked to their genetics and the environment they experience during growth,” says Rebecca Ong, an assistant professor of chemical engineering at Michigan Technological University. “Bioenergy production is no different. It’s a chain where every link, including the feedstock characteristics, influences the final product—the fuel.”

Ong is both a chemical engineer and a biologist. She holds a unique perspective on how the bioenergy system fits together, which comes in handy, especially now, in light of a recent puzzling discovery.

“Plants have lower biomass yields during a drought. You understand this when you don’t need to mow your lawn after a dry spell,” she explains. “The same is true with switchgrass. Besides the expected effect on crop yields, we were completely unable to produce fuel from switchgrass—using one of our standard biofuel microbes—grown during a major drought year.”

“At the lab scale this is an interesting result. But at the industrial scale, this could potentially be devastating to a biorefinery,” she says.

Ong, her research team, and colleagues within the Great Lakes Bioenergy Research Center (GLBRC), a cross-disciplinary research center led by the University of Wisconsin–Madison, are making efforts to understand, pulling in researchers from across the production chain to study the problem. 

Ong is the only Michigan Tech faculty member in the GLBRC. “Our team was able to identify some of the compounds formed in the plant in response to drought stress, contributing to the inhibition. But plant materials are very complex. We’ve only scratched the surface of what is in there. We have much more to learn.”

The first step, she says, is to understand what inhibits fuel production. “Once we know that, we can engineer solutions: new, tailor-made plants with improved characteristics, as well as modifications to processing, such as the use of different microbes, to overcome these issues.”

Ong points out that in the U.S., gasoline is largely supplemented with E10 ethanol, derived from sugars in corn grain. However renewable fuels can be produced from any source of sugars—including perennial grasses, which if planted on less productive land do not conflict with food production.

“Ultimately, if we are to replace fossil energy in the long term, we need a broad alternative energy portfolio,” says Ong. “We need industry to succeed. We are engaging in highly collaborative research to ensure that happens.”


Seismic Reflections: Siting the Gordie Howe Bridge

The Gordie Howe International Bridge connecting Windsor, Ontario, and Detroit, Michigan is currently under construction and expected to be complete in 2024 at a cost of $5.7 billion.  The bridge is named in recognition of the legendary hockey player, a Canadian who led the Detroit Red Wings to four Stanley Cup victories.

The construction of any large infrastructure project requires a strong foundation, especially one with the longest main span of any cable-stayed bridge in North America—namely, the Gordie Howe International Bridge over the Detroit River. More than a decade before ground was broken, careful siting of the bridge began to take place. By 2006 the list of possible crossings had been narrowed down to just two options.

Historical records from the early 1900s indicated that solution mining for salt had taken place on both sides of the river close to where the bridge was to be built. On the Michigan side, collapsed salt cavities caused sink holes located on nearby Grosse Isle. It was imperative that any salt cavities in the bridge construction area be found and avoided.

Seismologists Roger Turpening and Carol Asiala at Michigan Technological University

Seismologists Roger Turpening and Carol Asiala at Michigan Technological University were tasked by American and Canadian bridge contractors to select the best seismic method for searching for any cavities in the two proposed crossings—referred to at the time as “Crossing B” and “Crossing C”—and to interpret all resulting seismic images.

“Given the task to image a small target deep in the Earth, a seismologist will quickly ask two important questions: How small is ‘small?’ and How deep is ‘deep’? That’s because these two parameters conflict in seismic imaging,“ Turpening says.

“Seismic waves—vibrations of the Earth—are attenuated severely as they propagate through the Earth,” he explains. “Imaging small targets requires the use of high-frequency, seismic energy. When seismic sources and receivers are confined to the Earth’s surface, which is the usual case, waves must propagate downward through the Earth, reflect off of the target, and return to the surface. Soil, sand, and gravel in the surface layer overwhelmingly cause the greatest harm to image resolution, and the ray paths must pass through this zone twice.”

Turpening was one of the early developers of a technique called vertical seismic profiling, or VSP. “Seismic receivers are placed inside a vertical hole near the target. With the seismic source placed on the surface some distance from the hole, it’s possible to explore a region around the hole with ray paths that need to pass through the surface layer only once,” he says. “If the target is very important, we can drill a second hole and place the seismic source in it. Now we have even higher resolution because all of the ray paths are in the rock formations with low attenuation.”

The downside? “We can only make images of the region between the two holes. But if the target is extremely important in a limited area, we can use many boreholes and many images in the search. Given enough boreholes, a block of earth can be imaged with cross-well seismic reflection techniques.

A cross-well, seismic reflection image between test boreholes. The cavity is sharply seen because the shale stringers in the B-Salt (at the bottom of the image) are abruptly terminated. The cavity is approximately 375 ft. wide.

To site the Gordon Howie bridge, Turpening and Asiala chose a frequency band of 100Hz to 2 KHz—much higher than could be used with surface sources and surface receivers—for surveys on both sides of the river. This yielded high resolution seismic images, crucial for detecting cavities—and indeed they found one—on the Canadian side.

“The high-resolution imaging made it easy for us to spot missing shale stringers in the B-Salt layer in that image,” says Turpening. “This made the final selection of the bridge location simple. We found the cavity between boreholes X11-3 and X11-4, thus forcing the Canadians to chose Crossing B.  Obviously, the Michigan group had to, also, choose Crossing B.”

On the US side of the river geologist Jimmie Diehl, Michigan Tech professor emeritus, provided corroborating borehole gravity data.


Inspired by nature—Getting underwater robots to work together, continuously

Nina Mahmoudian, Mechanical Engineering-Engineering Mechanics
Nina Mahmoudian, Mechanical Engineering-Engineering Mechanics

Imagine deploying multiple undersea robots, all in touch and working together for months, even years, no matter how rigorous the mission, brutal the environment, or extreme the conditions.

It is possible, though not quite yet. “Limited energy resources and underwater communication are the biggest issues,” says Michigan Tech Researcher Nina Mahmoudian. Grants from a National Science Foundation CAREER Award and the Young Investigator Program from the Office of Naval Research are helping Mahmoudian solve those issues and pursue her ultimate goal: the persistent operation of undersea robots.

“Autonomous underwater vehicles (AUVs) are becoming more affordable and accessible to the research community,” she says. “But we still need multipurpose long-lasting AUVs that can adapt to new missions quickly and easily.”

Mahmoudian has already developed a fleet of low-cost, underwater gliders, ROUGHIEs, to do just that. Powered by batteries, they move together through the water simply by adjusting their buoyancy and weight. Each one weighs about 25 pounds. “ROUGHIE, by the way, stands for Research-Oriented Underwater Glider for Hands-on Investigative Engineering,” adds Mahmoudian.

“My most exciting observation was a Beluga mother and calf swimming together. It’s very similar to our recharge on-the-fly concept.”

Nina Mahmoudian

“The ROUGHIE’s open control architecture can be rapidly modified to incorporate new control algorithms and integrate novel sensors,” she explains. “Components can be serviced, replaced, or rearranged in the field, so scientists can validate their research in situ.” Research in underwater control systems, communication and networking, and cooperative planning and navigation all stand to gain.

Mahmoudian observes Mother Nature to design robotic systems. “There is so much to learn,” she says. “My most exciting observation was a Beluga mother and calf swimming together. It’s very similar to our recharge on-the-fly concept. The technology is an early stage of development.”

Mahmoudian’s students apply and implement their algorithms on real robots and test them in real environments. They also give back to the community, by teaching middle school students how to design, build, and program their own low-cost underwater robots using a simple water bottle, called a GUPPIE.

“As a girl growing up, I first thought of becoming an architect,” says Mahmoudian. “Then, one day I visited an exhibition celebrating the 30th anniversary of space flight. That’s when I found my passion.” Mahmoudian went on to pursue aerospace engineering in Iran, and then graduate studies at Virginia Tech in the Department of Aerospace and Ocean Engineering. “Underwater gliders share the same physical concepts as airplanes and gliders, but deal with different fluid density and interactions,” she says.

Now at Michigan Tech, Mahmoudian’s work advances the abilities of unmanned robotic systems in the air, on land, and under sea. “Michigan Tech has easy access to the North Woods and Lake Superior—an ideal surrogate environment for testing the kind of autonomous systems needed for long term, challenging expeditions, like Arctic system exploration, or searching for signs of life on Europa, Jupiter’s moon.” She developed the Nonlinear and Autonomous Systems Laboratory (NAS Lab) in 2011 to address challenges that currently limit the use of autonomous vehicles in unknown, complex situations.

More than scientists and engineers, Mahmoudian wants simple, low-cost AUV’s to be available to anyone who may need one. “I envision communities in the Third World deploying low-cost AUVs to test and monitor the safety and quality of the water they use.”


Demand dispatch—Balancing power in the grid in a nontraditional way

According to the National Renewable Energy Lab (NREL), distributed energy resources like these photovoltaic (PV) systems in a Boulder neighborhood—especially when they are paired with on-site storage—may eventually make large centralized power plants obsolete. Photo Credit: Topher Donahue
According to the National Renewable Energy Lab (NREL), distributed energy resources like these photovoltaic (PV) systems in a Boulder neighborhood—especially when they are paired with on-site storage—may eventually make large centralized power plants obsolete. Photo Credit: Topher Donahue

Traditionally, in the electric power grid, generation follows electric power consumption, or demand. Instantaneous fluctuation in demand is primarily matched by controlling the power output of large generators.

Sumit Paudyal, Electrical & Computer Engineering
Sumit Paudyal, Electrical & Computer Engineering

As renewable energy sources including solar and wind power become more predominant, generation patterns have become more random. Finding the instantaneous power balance in the grid is imperative. Demand dispatch—the precise, direct control of customer loads—makes it possible.

Michigan Tech researcher Sumit Paudyal and his team are developing efficient real-time control algorithms to aggregate distributed energy resources, and coordinate them with the control of the underlying power grid infrastructure.

“Sensors, smart meters, smart appliances, home energy management systems, and other smart grid technologies facilitate the realization of the demand dispatch concept,” Paudyal explains.

“The use of demand dispatch has promising potential in the US, where it is estimated that one-fourth of the total demand for electricity could be dispatchable using smart grid technologies.”

Sumit Paudyal

Coordination and control in real time is crucial for the successful implementation of demand dispatch on a large scale. “Our goal is to enable control dispatch distributed resources for the very same grid-level applications—frequency control, regulation, and load following—traditionally provided by expensive generators,” adds Paudyal.
“We have solved the demand dispatch problem of thermostatically-controlled loads in buildings and electric vehicle loads connected to moderate-size power distribution grids. The inherent challenge of the demand dispatch process is the computational complexity arising from the real-time control and coordination of hundreds to millions of customer loads in the system,” he adds. “We are now taking a distributed control approach to achieve computational efficiency in practical-sized, large-scale power grids.”


Vital signs—Powering heart monitors with motion artifacts

Electrocardiogram research Ye Sarah Sun

More than 90 percent of US medical expenditures are spent on caring for patients who cope with chronic diseases. Some patients with congestive heart failure, for example, wear heart monitors 24/7 amid their daily activities.

Ye Sarah Sun
Ye Sarah Sun, Mechanical Engineering-Engineering Mechanics

Michigan Tech researcher Ye Sarah Sun develops new human interfaces for heart monitoring. “There’s been a real trade-off between comfort and signal accuracy, which can interfere with patient care and outcomes,” she says. Sun’s goal is to provide a reliable, personalized heart monitoring system that won’t disturb a patient’s life. “Patients need seamless monitoring while at home, and also while driving or at work,” she says.

Sun has designed a wearable, self-powered electrocardiogram (ECG) heart monitor. “ECG, a physiological signal, is the gold standard for diagnosis and treatment of heart disease, but it is a weak signal,” Sun explains. “When monitoring a weak signal, motion artifacts arise. Mitigating those artifacts is the greatest challenge.”

Sun and her research team have discovered and tapped into the mechanism underlying the phenomenon of motion artifacts. “We not only reduce the in uence of motion artifacts but also use it as a power resource,” she says.

Their new energy harvesting mechanism provides relatively high power density compared with traditional thermal and piezoelectric mechanisms. Sun and her team have greatly reduced the size and weight of an ECG monitoring device compared to a traditional battery-based solution. “The entire system is very small,” she says, about the size of a pack of gum.

“We not only reduce the influence of motion artifacts but also use it as a power resource.”

Ye Sarah Sun

Unlike conventional clinical heart monitoring systems, Sun’s monitoring platform is able to acquire electrophysiological signals despite a gap of hair, cloth, or air between the skin and the electrodes. With no direct contact to the skin, users can avoid potential skin irritation and allergic contact dermatitis, too—something that could make long-term monitoring a lot more comfortable.

Ye Sarah Sun self-powered ECG heart monitor
Sun’s self-powered ECG heart monitor works despite a gap of hair, cloth or air between the user’s skin and the electrodes.