Category: Research

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.”

Catechol-Based Adhesive Research

Bruce P. Lee
Bruce P. Lee, Associate Professor, Biomedical Engineering

Research by Ameya R. Narkar, Jonathan D. Kelley, Rattapol Pinnaratip, and Bruce P Lee has been accepted in Biomacromolecules.

DOI: 10.1021/acs.biomac.7b01311

Effect of Ionic Functional Groups on the Oxidation State and Interfacial Binding Property of Catechol-Based Adhesive” involves the study of marine mussels, which secrete catechol-containing adhesive proteins for underwater binding to surfaces like ship hulls and docks Catechol has been used by scientists and engineers around the world to design synthetic adhesives and coatings for wide ranges of applications. It can be used in tissue adhesive, tissue engineering scaffold, coating for preventing adhesion of bacteria, and so on.

It is shown, however, that in the presence of neutral to basic pH (for example, pH 7.4 in the body or pH 7.5-8.4 in the ocean), catechol oxidizes, leading to reduced adhesive strength. Mussels actually utilize multiple adhesive proteins with various ingenious designs to prevent catechol oxidation and to preserve strong adhesion. The adhesive proteins exhibit antioxidant properties, hydrophobicity for avoiding contact with basic sea water, and other methods in order to optimize adhesion.

We found that incorporation of acidic functional groups in the adhesive network can also prevent catechol oxidation, preserving strong adhesion, even up to a pH of 8.5. This is a much simpler approach than what the mussels employ and potentially easier for designing synthetic mimics of these adhesive proteins. This means that we will be able to design biomimetic adhesives for biomedical applications and underwater applications, which are the basic pH environments of interest.

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.

Where rubber becomes the road—Testing sustainable asphalt technologies

Zhanping You research team
A Michigan Tech research team led by Zhanping You tests a new, cooler way to make rubberized asphalt.

Over 94% of the roads in the United States are paved with asphalt mix. Each year, renovating old highways with new pavement consumes about 360 million tons of raw materials. It also generates about 60 million tons of old pavement waste and rubble.

Zhanping You, Civil & Environmental Engineering
Zhanping You, Civil & Environmental Engineering

Recycling these waste materials greatly reduces the consumption of neat, unmodified asphalt mix and lowers related environmental pollution. But blending recycled asphalt pavement (RAP) with fresh asphalt mix presents several challenges, potentially limiting its usefulness.

Not to Michigan Tech researcher Zhanping You. “One noticeable issue of using RAP in asphalt pavement is the relatively weaker bond between the RAP and neat asphalt, which may cause moisture susceptibility,” he explains. “Modifying the asphalt mix procedure and selecting the proper neat asphalt can effectively address this concern.”

You tests a variety of recycled materials to improve asphalt pavement performance. Crumb rubber, made from scrap tires, is one such material. “Crumb rubber used in asphalt reduces rutting and cracks, extends life, and lowers noise levels. Another plus—building one mile of road with crumb rubber uses up to 2,000 scrap tires. Hundreds of millions of waste tires are generated in the US every year,” he adds.

Adding crumb rubber to asphalt mix has its own share of problems. “When crumb rubber is blended into asphalt binder, the stiffness of the asphalt binder is increased. A higher mixing temperature is needed to preserve the flowability. Conventional hot-mix asphalt uses a lot of energy and releases a lot of fumes. We use a foaming process at lower temperatures that requires less energy and reduces greenhouse gas emissions.”

“Building one mile of road with crumb rubber uses up to 2,000 scrap tires. Hundreds of millions of waste tires are generated in the US every year.”

—Zhanping You

You and his team integrate state-of-the-art rheological and accelerated-aging tests, thermodynamics, poromechanics, chemical changes, and multiscale modeling to identify the physical and mechanical properties of foamed asphalt materials. With funding from the Michigan Department of Environmental Quality, they have constructed test sections of road in two Michigan counties to monitor field performance.

Another possible solution is asphalt derived from biomass. You’s team used bio oil in asphalt and found it improved pavement performance. They’re also investigating nanomaterial-modified asphalt. “Soon we’ll have mix recipes to adapt to all environmental and waste supply streams,” he says.

The holy grail of energy storage—Solving the problems of lithium anodes

Samsung exploded phone
A damaged Samsung Galaxy Note 7 after its lithium battery caught fire. Photo Credit: Shawn L. Minter, Associated Press

State-of-the-art mechanical characterization of pure lithium metal, performed at submicron-length scales, provides signifcant physical insight into critical factors that limit the performance of next generation energy storage devices.

Erik Herbert, Michigan Tech
Erik Herbert, Materials Science & Engineering

Compared to competing technology platforms, a pure lithium anode potentially offers the highest possible level of volumetric and gravimetric energy density. Gradual loss of lithium over the cycle life of a battery prevents the full fruition of this energy technology.

Michigan Tech researchers Erik Herbert, Stephen Hackney, and their collaborators at Oak Ridge National Laboratory and the University of Michigan are investigating the behavior of a lithium anode accessed through, and protected by, polycrystalline superionic solid electrolytes. Their goals: Mitigate the loss of lithium; prevent dangerous side reactions; and enable safe, long-term, and high-rate cycling performance.

“We want to maintain efficient cycling of lithium in a battery over many cycles, something that’s never been done before,” says Herbert. “The fundamental challenge is figuring out how to maintain a coherent interface between the lithium anode and the solid electrolyte. Defects formed in the lithium during cycling determine the stability and resistivity of the interface. Once we see how that happens, it will reveal design rules necessary to successfully fabricate the solid electrolyte, and the battery packaging.”

The team is launching parallel efforts to address these issues. Herbert, for his part, wants to learn exactly how lithium is consumed on a nanoscale level, in real time. “We want to know why the interface becomes increasingly resistive with cycling, how the electrolyte eventually fails, how defects in the lithium migrate, agglomerate, or anneal with further cycling or time, and whether softer electrolytes can be used without incursion of metallic lithium into the electrolyte,” he says. “We also want to learn how processing and fabrication affect interface performance.”

“We want to maintain efficient cycling of lithium in a battery over many cycles, something that’s never been done before.”

Erik Herbert

polycrystalline lithium film
Surface of the polycrystalline lithium film, with over 100 residual impressions from targeted test sites

To answer these questions, Herbert conducts nano-indentation studies on vapor-deposited lithium films, various sintered solid electrolytes, and lithium films in fully functional solid-state batteries.

“The data from these experiments directly enable exam-ination of the complex coupling between lithium’s micro-structure, its defects, and its mechanical behavior,” says Herbert. “So far we’ve gained a better understanding of the mechanisms lithium utilizes to manage pressure (stress) as a function of strain, strain rate, temperature, defect structure, microstructural length scale, and in-operando cycling of the battery.”

Atomic resolution image of a spinel intergrowth lithium ion battery electrode particle and associated convergent beam electron diffraction pattern. The ordered dots all over the black triangle (the particle) are atomic columns, with a convergent beam electron diffraction pattern in white at the top. These results were obtained with the FEI 200kV Titan Themis Scanning Transmission Electron Microscope (S-TEM) recently commissioned by Michigan Tech.
These results were obtained with the FEI 200kV Titan Themis Scanning Transmission Electron Microscope (S-TEM) recently commissioned by Michigan Tech.

Atomic resolution image of a spinel intergrowth lithium ion battery electrode particle and associated convergent beam electron diffraction pattern. The ordered dots all over the black triangle (the particle) are atomic columns, with a convergent beam electron diffraction pattern in white at the top.

 

Michigan Tech's FEI 200kV Titan Themis Scanning Transmission Electron Microscope (S-TEM) positions Michigan Tech faculty on the leading edge of new imaging capability for structural and chemical analysis at the nano-scale.
Michigan Tech’s FEI 200kV Titan Themis Scanning Transmission Electron Microscope (S-TEM)

Michigan Tech’s FEI 200kV Titan Themis Scanning Transmission Electron Microscope (S-TEM) positions Michigan Tech faculty on the leading edge of new imaging capability for structural and chemical analysis at the nano-scale.

Prevascularization of Natural Nanofibrous Extracellular Matrix

Lijun Zhang (former research fellow), Zichen Qian, Shaohai Qi (collaborator), and Feng Zhao have an accepted manuscript “Prevascularization of Natural Nanofibrous Extracellular Matrix for Engineering Completely Biological 3D Prevascularized Tissues for Diverse Applications” in the Journal of Tissue Engineering and Regenerative Medicine.

Feng Zhao is an associate professor in the Department of Biomedical Engineering. Zhao specializes in stem cell and tissue engineering research.

doi: 10.1002/term.2512

The study indicated that a preformed functional vascular network provides an effective solution for solving the mass transportation problem in large engineered tissues after implantation. Microvessels were created on a stem cell sheet by controlling microenvironmental parameters including oxygen and nanostructure. The prevascularized stem cell sheet holds great promise for engineering 3D prevascularized tissues for diverse applications.

3D Prevascularized Tissue
3D Prevascularized Tissue

AV START Act May Boost Autonomous Vehicle Testing

Gary Peters and Jeff Naber
U.S. Sen. Gary Peters and Jeff Naber

HOUGHTON — Testing of autonomous vehicles, such as that being done at Michigan Technological University, could get a boost with legislation working its way through Congress.

The American Vision for Safer Transportation through Advancement of Revolutionary Technologies (AV START) Act was approved by the Senate Commerce, Science and Transportation Committee in October. U.S. Sen.

Gary Peters, D-Mich., sponsored the bill along with Sen. John Thune, R-S.D. U.S. Sen. Debbie Stabenow, D-Mich., is a co-sponsor of the legislation.

In March, Peters visited Tech’s Advanced Power System Research Center to get informed of Tech’s research and development efforts into autonomous vehicles.

Jeff Naber, director of the center, said the bill will enable the advancement of autonomous vehicle functions.

Read more at the Mining Gazette, by Garrett Neese.

Working Luncheon, MDOT Call For Research Ideas

MDOT PavementThe MDOT Office of Research is soliciting research priority ideas for their upcoming funding years FY19/20/21. This is a great opportunity for Michigan Tech researchers from various departments to expand their research portfolio into transportation topics.

The topics are very versatile, from hard core pavement engineering to water and environmental aspects, life cycle cost engineering, even workforce development. Details on MDOT research priorities can be found here.

In the past, Michigan Tech Transportation Institute (MTTI) has submitted Tech’s research ideas to MDOT as a combined package for a stronger, unified presence. Our plans are to do so again.

From noon to1 p.m. Thursday (Nov. 9, 2017), in Dillman 309A, MTTI will be hosting a lunch meeting for discussions, gathering of ideas and to provide a setting for collaboration on the research idea topics listed. We will also share a couple of past ideas that were later turned by MDOT to RFPs and we’ll provide some insight from discussions with MDOT.

We’ve created a spreadsheet to gather information on topic ideas you’re interested in providing to MDOT. Email Pam Hannon to get a link to the spreadsheet. Contact Pam also, if you’d like to join us in the meeting by Tuesday (Nov. 7).

Michigan Tech Joins Academic Consortium at the American Society for Mobility

Semi-Autonomous VehicleDetroit News reported on the American Society for Mobility’s  self-driving research site in Ypsilanti, Michigan, and its new partnership with 15 Michigan universities, including Michigan Tech. The partnership will lead to training, courses, recruitment, internships, co-ops and work-study programs. The article was featured in First Bell, a daily science and engineering newsletter published by the American Society for Engineering Education (ASEE).

In addition, Michigan Tech is one of three Michigan universities whose students have been invited to participate in a three-year autonomous vehicle competition sponsored by General Motors and SAE.

The topic of autonomous vehicles was addressed during the inaugural Mobility Summit at Michigan Tech in April 2017. The event brought together interdisciplinary teams and keynote speakers to discuss the whole vehicle system, the larger infrastructure, and the human systems in which it is embedded.

The summit was organized by Michigan Tech’s mobility-affiliated research centers and institutes, the Vice President for Research, and the College of Engineering.

Colleges partner with Willow Run mobility center

Ypsilanti — Leadership at the American Center for Mobility here plans to cultivate high-tech talent from 15 Michigan colleges and universities through a partnership aimed at preparing and retaining new engineers to work on the vehicles of the future.

The self-driving research site at Ypsilanti’s Willow Run will open in December, President and CEO of the center, John Maddox, said. Maddox and Gov. Rick Snyder want to make sure local students graduating from the state’s colleges and universities are ready to work on the high-tech, high-demand connected and automated technology that will be developed, prototyped and tested by automakers and suppliers on the 500-acre facility.

Maddox, Snyder and representatives from the University of Michigan, Michigan State University, Michigan Tech, University of Detroit Mercy, Grand Valley State University and Wayne State University, among others, signed a memorandum of understanding to form the academic consortium at the American Center for Mobility.

Read more at The Detroit News, by Ian Thibodeau.

Mich. universities push ahead on autonomous vehicles

Southfield — On the small campus of Lawrence Technological University, a few students are on the cusp of programming one of the nation’s first autonomous vehicles as a class project.

Many other colleges are involved in autonomous vehicle research, testing and training, including Michigan State University and Oakland University. Three Michigan colleges, Kettering University, Michigan Technological University and MSU, are part of a three-year North American autonomous vehicle competition.

Read more at The Detroit News, by Kim Kozlowski.