A strong and ductile high-entropy alloy
Ting Zhu, Woodruff Professor in the George W. Woodruff School of Mechanical Engineering at Georgia Tech

A team of researchers at the University of Massachusetts Amherst and the Georgia Institute of Technology has 3D printed a dual-phase, nanostructured high-entropy alloy that exceeds the strength and ductility of other state-of-the-art additively manufactured materials, which could lead to higher-performance components for applications in aerospace, medicine, energy and transportation. The research, led by Wen Chen, assistant professor of mechanical and industrial engineering at UMass, and Ting Zhu, professor of mechanical engineering at Georgia Tech, was published in the August issue of the journal Nature.

Over the past 15 years, high entropy alloys (HEAs) have become increasingly popular as a new paradigm in materials science. Comprised of five or more elements in near-equal proportions, they offer the ability to create a near-infinite number of unique combinations for alloy design. Traditional alloys, such as brass, carbon steel, stainless steel and bronze, contain a primary element combined with one or more trace elements.

Additive manufacturing, also called 3D printing, has recently emerged as a powerful approach of material development. The laser-based 3D printing can produce large temperature gradients and high cooling rates that are not readily accessible by conventional routes. However, “the potential of harnessing the combined benefits of additive manufacturing and HEAs for achieving novel properties remains largely unexplored,” says Zhu.

Chen and his team in the Multiscale Materials and Manufacturing Laboratory combined an HEA with a state-of-the-art 3D printing technique called laser powder bed fusion to develop new materials with unprecedented properties. Because the process causes materials to melt and solidify very rapidly as compared to traditional metallurgy, “you get a very different microstructure that is far-from-equilibrium” on the components created, Chen says. This microstructure looks like a net and is made of alternating layers known as face-centered cubic (FCC) and body-centered cubic (BCC) nanolamellar structures embedded in microscale eutectic colonies with random orientations. The hierarchical nanostructured HEA enables co-operative deformation of the two phases.

“This unusual microstructure’s atomic rearrangement gives rise to ultrahigh strength as well as enhanced ductility, which is uncommon, because usually strong materials tend to be brittle,” Chen says. Compared to conventional metal casting, “we got almost triple the strength and not only didn’t lose ductility, but actually increased it simultaneously,” he says. “For many applications, a combination of strength and ductility is key. Our findings are original and exciting for materials science and engineering alike.”

“The ability to produce strong and ductile HEAs means that these 3D printed materials are more robust in resisting applied deformation, which is important for lightweight structural design for enhanced mechanical efficiency and energy saving,” says Jie Ren, Chen’s Ph.D. student and first author of the paper.

Zhu’s group at Georgia Tech led the computational modeling for the research. He developed dual-phase crystal plasticity computational models to understand the mechanistic roles played by both the FCC and BCC nanolamellae and how they work together to give the material added strength and ductility. 

“Our simulation results show the surprisingly high strength yet high hardening responses in the BCC nanolamellae, which are pivotal for achieving the outstanding strength-ductility synergy of our alloy. This mechanistic understanding provides an important basis for guiding the future development of 3D printed HEAs with exceptional mechanical properties,” Zhu says.

In addition, 3D printing offers a powerful tool to make geometrically complex and customized parts. In the future, harnessing 3D printing technology and the vast alloy design space of HEAs opens ample opportunities for the direct production of end-use components for biomedical and aerospace applications.

Additional research partners on the paper include Texas A&M University, the University of California Los Angeles, Rice University, and Oak Ridge and Lawrence Livermore national laboratories.

Story by Melinda Rose, Associate News Editor at UMass Amherst. 

News Contact

Catherine Barzler, Georgia Tech

Tom Kurfess

The Georgia Institute of Technology has selected Thomas R. Kurfess as the new executive director of the Georgia Tech Manufacturing Institute (GTMI). Kurfess is the HUSCO/Ramirez Distinguished Chair in Fluid Power and Motion Control and professor of mechanical engineering at Georgia Tech. He received his S.B., S.M., and Ph.D. degrees in mechanical engineering from the Massachusetts Institute of Technology (MIT) and received an S.M. degree from MIT in electrical engineering and computer science.

“Chaouki Abdallah, executive vice president for research, and I are very excited about Tom taking on this role. Advanced manufacturing is a top federal priority as an ‘industry of the future.’ Tom’s experience and international reputation from his history in academia, industry, and the government will be a great complement to our existing vibrant community of students, staff, and faculty committed to manufacturing research and education—positioning Georgia Tech to meet regional, national, and global needs,” said Julia Kubanek, vice president for interdisciplinary research at Georgia Tech.

“We’re grateful for the efforts of the search committee led by Professor Meisha Shofner and to the leadership of Professor Ben Wang as executive director of GTMI for 11 years until he stepped down at the end of May. We also appreciate Professor Shreyes Melkote for serving as interim director this month while we finalized Tom’s appointment.”

Kurfess first joined the faculty at Georgia Tech in 1994, and has taken on a variety of special assignments in addition to his teaching and research.

His research focuses on the design and development of advanced manufacturing systems targeting secure digital manufacturing, additive and subtractive processes, and large-scale production enterprises. He is a member of the National Academy of Engineering and is a fellow of the American Association for the Advancement of Science (AAAS), the American Society of Mechanical Engineers (ASME) and the Society of Manufacturing Engineers (SME). He was president of SME in 2018, and currently serves on the Board of Governors of the American Society of Mechanical Engineers (ASME).

During 2019-2021, Kurfess was on leave serving as the chief manufacturing officer at Oak Ridge National Laboratory (ORNL) where he was responsible for strategic planning for ORNL in advanced manufacturing. He was also the founding director for the Manufacturing Science Division at ORNL.

He served as the assistant director for advanced manufacturing at the Office of Science and Technology Policy in the executive office of the President of the United States of America from 2012-2013, where he was responsible for coordinating federal advanced manufacturing research and development.

“For decades, Georgia Tech has led the Nation’s academic institutions in the advanced manufacturing sector. It is an honor for me to be tapped to continue our efforts in this area. I am excited to take the helm at the Georgia Tech Manufacturing Institute (GTMI) in continuing its role as a technology leader in advanced manufacturing for the State of Georgia, the United States, and the world. We will be a conduit enabling the Georgia Tech community in their efforts to accelerate and develop manufacturing technologies and workforce capabilities, providing a forum in which they can openly collaborate, and facilities that are world-class for their efforts. I look forward to engaging a wide range of traditional and nontraditional teams integrating technical areas with business, economic, and policy areas to provide a manufacturing basis for the U.S. and the world that will ensure a strong, just, secure and equitable future for society,” said Kurfess.

“Given that GTMI is one of Georgia Tech’s Interdisciplinary Research Institutes, I look forward to engaging a wide range of traditional and nontraditional teams integrating technical areas with business, economic, and policy areas to provide a manufacturing basis for the U.S. and the world that will ensure a strong, just, secure and equitable future for society.”

The Georgia Tech Manufacturing Institute (GTMI) is one of Georgia Tech’s 10 interdisciplinary research institutes, and an integral part of the broader Georgia Tech research enterprise. In 2021, GTMI celebrated its 30th anniversary. GTMI's mission is to convene industry leaders, government partners, and top researchers to collaborate on the grand challenges facing the U.S. manufacturing industry today: accelerating technology development and deployment, creating quality jobs, ensuring global competitiveness, and advancing economic and environmental stability.

5G+ (5G/Beyond 5G) is the fastest-growing segment and the only significant opportunity for investment growth in the wireless network infrastructure market, according to the latest forecast by Gartner, Inc. But currently 5G+ technologies rely on large antenna arrays that are typically bulky and come only in very limited sizes, making them difficult to transport and expensive to customize.

Researchers from Georgia Tech’s College of Engineering have developed a novel and flexible solution to address the problem. Their additively manufactured tile-based approach can construct on-demand, massively scalable arrays of 5G+ (5G/Beyond 5G)‐enabled smart skins with the potential to enable intelligence on nearly any surface or object. The study, recently published in Scientific Reports, describes the approach, which is not only much easier to scale and customize than current practices, but features no performance degradation whenever flexed or scaled to a very large number of tiles.

“Typically, there are a lot of smaller wireless network systems working together, but they are not scalable. With the current techniques, you can’t increase, decrease, or direct bandwidth, especially for very large areas,” said Manos Tentzeris, Ken Byers Professor in Flexible Electronics in the School of Electrical and Computer Engineering. “Being able to utilize and scale this novel tile-based approach makes this possible.”

Tentzeris says his team’s modular application equipped with 5G+ capability has the potential for immediate, large-scale impact as the telecommunications industry continues to rapidly transition to standards for faster, higher capacity, and lower latency communications.

BUILDING THE TILES

In Georgia Tech’s new approach, flexible and additively manufactured tiles are assembled onto a single, flexible underlying layer. This allows tile arrays to be attached to a multitude of surfaces. The architecture also allows for very large 5G+ phased/electronically steerable antenna array networks to be installed on-the-fly. According to Tentzeris, attaching a tile array to an unmanned aerial vehicle (UAV) is even a possibility to surge broadband capacity in low coverage areas.

In the study, the team fabricated a proof-of-concept, flexible 5×5-centimeter tile array and wrapped it around a 3.5-centimeter radius curvature. Each tile includes an antenna subarray and an integrated, beamforming integrated circuit on an underlying tiling layer to create a smart skin that can seamlessly interconnect the tiles into very large antenna arrays and massive multiple-input multiple-outputs (MIMOs) — the practice of housing two or more antennas within a single wireless device. Tile-based array architectures on rigid surfaces with single antenna elements have been researched before, but do not include the modularity, additive manufacturability, or flexible implementation of the Georgia Tech design.

The proposed modular tile approach means tiles of identical sizes can be manufactured in large quantities and are easily replaceable, reducing the cost of customization and repairs. Essentially, this approach combines removable elements, modularity, massive scalability, low cost, and flexibility into one system.

5G+ IS JUST THE BEGINNING

While the tiling architecture has demonstrated the ability to greatly enhance 5G+ technologies, its combination of flexible and conformal capabilities has the potential to be applied in numerous different environments, the Georgia Tech team says.

“The shape and features of each tile scale can be singular and can accommodate different frequency bands and power levels,” said Tentzeris. “One could have communications capabilities, another sensing capabilities, and another could be an energy harvester tile for solar, thermal, or ambient RF energy. The application of the tile framework is not limited to communications.”

Internet of Things, virtual reality, as well as smart manufacturing/Industry 4.0 — a technology-driven approach that utilizes internet-connected “intelligent” machinery to monitor and fully automate the production process — are additional areas of application the team is excited to explore.

“The tile-architecture’s mass scalability makes its applications particularly diverse and virtually ubiquitous. From structures the size of dams and buildings, to machinery or cars, down to individual health-monitoring wearables,” said Tentzeris. “We’re moving in a direction where everything will be covered in some type of a wireless conformal smart skin encompassing electronically steerable antenna arrays of widely diverse sizes that will allow for effective monitoring.”

The team now looks forward to testing the approach outside the lab on large, real-world structures. They are currently working on the fabrication of much larger, fully inkjet-printed tile arrays (256+ elements) that will be presented at the upcoming International Microwave Symposium (IEEE IMS 2022) – the flagship IEEE conference in RF and microwave engineering. The IMS presentation will introduce a new tile-based large-area architecture version that will allow assembly of customizable tile arrays in a rapid and low-cost fashion for numerous conformal platforms and 5G+ enabled applications.

****

The authors declare no competing interests.

This work was supported in part by the National Science Foundation.

CITATIONS: He, X., Cui, Y. & Tentzeris, M.M. Tile-based massively scalable MIMO and phased arrays for 5G/B5G-enabled smart skins and reconfigurable intelligent surfaces. Sci Rep 12, 2741 (2022). https://doi.org/10.1038/s41598-022-06096-9

K.Hu, G.S.V.Angulo, Y.Cui and M.M.Tentzeris, “Flexible and Scalable Additively Manufactured Tile-Based Phased Arrays for Satellite Communications and 5G mmWave Applications,” accepted for presentation at IEEE International Microwave Symposium (IMS) 2022, Denver, CO, June 2022.

News Contact

Dan Watson
dwatson@ece.gatech.edu

Aaron Stebner leads lab class at Advanced Manufacturing Pilot Facility at Georgia Tech

The global supply chain has been rocked by disruptions triggered largely by the coronavirus pandemic, resulting in a cascade of shortages on a host of products ranging from computer chips to medications.  

But supply chain disruptions also highlight the potential vulnerabilities in the U.S. manufacturing sector’s critical segments like defense.

To help manufacturers across the state, the Georgia Institute of Technology has launched the Georgia Manufacturing 4.0 Consortium to work with those businesses in defense and related industries become more resilient and less susceptible to supply chain disruptions. The Consortium, which will begin accepting members in April 2022, will work with Georgia defense manufacturers to incorporate cybersecurity protocols, smart technologies such as sensor packs, machine learning, artificial intelligence, and other best practices under Industry 4.0 technology standards.

Led by Aaron Stebner, associate professor in the George W. Woodruff School of Mechanical Engineering and the School of Materials Science and Engineering, the Consortium is an 18-month pilot funded by a Department of Defense Office of Local Defense Community Cooperation (OLDCC) grant of nearly $1 million. Georgia Tech is working in partnership with Spelman College, the Technical College System of Georgia, and the Georgia Department of Economic Development, under the grant to develop workforce, training manuals, a curriculum, and to support businesses in adapting to economic and technological changes that emerge at a much more rapid pace today.

“It’s a cooperative effort that’s really focused on helping to get modern technologies to these Georgia manufacturers. This is about establishing a community of manufacturers who all want to move forward but don’t have the bandwidth or capabilities do it individually,” Stebner said.

The Consortium has three goals. The first is to increase the manufacturing defense supply chain’s resilience and diversification. That will allow those companies to pivot quickly in response to demand and let non-defense-related industries enter the supply chain at critical junctures. The second goal is to work with Georgia manufacturers in adopting new technologies and address challenges that put those businesses at risk.

Lastly, the Consortium is to be a conduit that helps small- and medium-sized manufacturers test out innovations using Georgia Tech resources such as the Advanced Manufacturing Pilot Facility, connect manufacturers with each other, and potentially unlock new markets and collaboration opportunities.

While the focus is on defense manufacturing, the Consortium is open to all manufacturers.

“We want to help as many manufacturers as we can, to grow a bigger pie that helps everybody, lowers risk, and allows companies to be part of building innovative solutions” Stebner said.

 

Manufacturing Supports Georgia Economy

National Association of Manufacturers data show that manufacturing accounts for $61.1 billion in economic activity, roughly 10% of Georgia’s total output. The industry includes more than 6,600 firms that employ nearly 400,000.

At $14 billion a year, Georgia is ranked 13th in federal defense spending. Roughly 1,200 manufacturers in the state are in defense or related industries. Those include information technology companies that support cybersecurity, wireless communications, and other innovations that are critically essential to Industry 4.0 in defense manufacturing.

University partners from the Technical College System of Georgia and Spelman College will look to take the Consortium findings and data from the work they do with member companies to create educational programming and workforce training. 

Today, there is a need for more workers in machine learning and other aspects of advanced manufacturing, as well as a need to change perceptions of manufacturing, especially in rural parts of the state, Stebner explained.

To that end, the Technical College System of Georgia could develop programming for students within its two-year education curriculum. It also has a mobile manufacturing unit that could be taken to rural parts of the state and used as a tool to highlight opportunities in manufacturing and dispel misconceptions about the industry.

The all-women’s Spelman College, one of the nation’s premier historically black colleges and universities, launched an extended reality program in the fall of 2020. That program aims to integrate art, technology, and narrative on a gaming platform which is familiar and engaging for students. Those students will develop the technical skills to develop games, create immersive virtual experiences, and develop visual simulations for research, education, and training.

For Consortium members, Spelman’s extended reality program can be used to help turn research data gathered from them into workforce training and development modules.

“Spelman has a long history of graduating women in the natural sciences, and that history has recently led the Department of Defense to distinguish the College as a Center of Excellence for educating women in STEM,” said Jerry Volcy, a Spelman professor and co-director of the Spelman Innovation Lab.

The extended reality program furthers Spelman’s goal to increase the technological readiness of its graduates.

“Spelman has a long record of forging pathways for women of color into new spaces. Today, these spaces include extended reality, defense and, to some extent, manufacturing research,” Volcy said. “From the College’s perspective, participation in the Consortium has the dual potential of creating and discovering new pathways into these industries while immediately providing real-world applications laboratory for the developing extended reality program.”

 

Fulfilling Georgia Tech’s Mission 

Within Georgia Tech, the Georgia Manufacturing Extension Partnership and the Georgia Tech Manufacturing Institute will support Consortium efforts.

The Consortium reflects Georgia Tech’s broader mission to further its Advanced Manufacturing Initiative, said George White, Georgia Tech’s interim vice president of Industry Collaboration.

“The anticipated research impact envisioned through the Defense Manufacturing Consortium will strengthen Georgia Tech’s positioning in enabling major public private collaborations,” White said. “The advent of the Consortium represents the opportunity to convene key stakeholders from government, academics, and industry to innovate and solve the most challenging problems in manufacturing.”

News Contact

Writer and media relations contact:

Péralte C. Paul
peralte.paul@comm.gatech.edu
404.316.1210

gina raimondo, Àngel Cabrera, Lindsey Lanzillotta

The Georgia Institute of Technology was awarded a grant from the U.S. Department of Commerce’s Economic Development Administration (EDA) as part of its $1 billion Build Back Better Regional Challenge. Georgia Tech is one of 60 entities to be awarded funding to assist communities nationwide in their efforts to accelerate the rebuilding of their economies in the wake of the pandemic.

As a leader in artificial intelligence, manufacturing research, and innovation-led economic development, Georgia Tech will utilize the grant for technical assistance to plan the Georgia Artificial Intelligence Manufacturing Corridor (GA-AIM). Led by Thomas Kurfess and Aaron Stebner in the George W. Woodruff School of Mechanical Engineering and in collaboration with local partners, GA-AIM will fill existing technology gaps, build a technological opportunity framework that includes underrepresented communities and rural Georgia counties, and better secure the state’s manufacturing infrastructure.

Georgia Tech’s partners in the effort include the Russell Innovation Center for EntrepreneursSpelman College, the Technical College System of Georgia, and the Georgia Department of Economic Development.

“We are truly honored to be awarded this grant to implement our vision for manufacturing excellence in Georgia with our partners in artificial intelligence research,” said Chaouki T. Abdallah, executive vice president for Research at Georgia Tech. “Alongside these important partners, the grant enables us to collaborate to include diverse backgrounds and perspectives in the process of learning, discovery, and creation, furthering Georgia Tech’s mission to expand access.”  

Georgia Tech and its partners will pair artificial intelligence and manufacturing research innovation to better secure the manufacturing ecosystem, expand opportunity to distressed and rural communities and underrepresented groups, and support business growth across the state.

“We are thrilled to help communities work together — in coalitions of government, nonprofits, academia, the private sector, and others — to craft ambitious and regionally unique plans to rebuild their communities,” said Alejandra Y. Castillo, assistant secretary of commerce for the EDA. “These projects will help revitalize local economies and tackle our biggest challenges related to climate change, manufacturing, supply chains, and more. EDA is proud to ignite these plans and help communities nationwide build back better.”

GA-AIM’s partners have created a complementary network of resources that focus on each partner organization’s expertise and mission.

“We have an opportunity to create meaningful impact at the intersection of AI and manufacturing,” said Stebner, who wrote the grant proposal that resulted in the $500,000 grant from EDA.

Kurfess, who serves as the regional economic competitiveness officer for the grant, added, “Bringing together AI and manufacturing will ensure a strong manufacturing base for Georgia that will leverage our well-trained workforce and our strong educational institutions that are participating in this effort. What excites me the most is that AI will augment our workforce, making it more valuable and productive, ensuring job growth for Georgia and the U.S. well into the future.”

The GA-AIM effort takes a multifaceted approach to address its core goals:

Georgia Tech

  • Formation of the AI Manufacturing Pilot Facility: Georgia Tech’s Advanced Manufacturing Pilot Facility will be transformed into the AI Manufacturing Pilot Facility. The new facility allows for government pilot trials, cybersecurity games, and workforce training to innovate, transition, and create a workforce for AI manufacturing technologies without exposing the region’s supply chains to risk.
  • Center for AI Commercialization: Two of Georgia Tech’s commercialization programs — VentureLab and I-Corps South — will create a center for the commercialization of AI manufacturing technologies into local and regional startups. Those commercialization efforts will occur through a quarterly cohort-based entrepreneurial training program built on the National Science Foundation’s I-Corps curriculum. The center will also provide training for instructors to build a sustainable workforce and will secure investment funding for these startups.
  • AI Manufacturing Community Engagement: The Enterprise Innovation Institute, Georgia Tech’s chief economic development arm, will engage in focused outreach and technical assistance to small and mid-sized manufacturers and minority business enterprises through its Georgia Manufacturing Extension Partnership and Georgia Minority Business Development Agency Business Center programs. A third Enterprise Innovation Institute program, the Economic Development Lab, will focus on outreach and engagement in distressed and underserved parts of the state, create workforce development programs and implementation strategies, and attract outside investment.
  • AI Manufacturing Rural Supply Chain: The Supply Chain and Logistics Institute will study the impact of automation technologies, build automation solutions tailored for rural manufacturers, and create programs that lower the barrier for rural manufacturers’ access to use the AI Manufacturing Pilot Facility.
  • AI InVenture K-12 Experiences: To ensure a technically capable workforce in the coming years, Georgia Tech’s InVenture Prize and the Center for Education Integrating Science, Mathematics, and Computing will expand their emphasis to rural and underserved areas of the state by piloting a rural regional event with a region-specific prize. They will also create supplemental lessons centered on AI and data science that will be part of a K-12 InVenture Prize curriculum website.

Spelman College

  • Virtual Reality for AI Workforce Training Innovation: Spelman’s Innovation Lab will develop virtual reality technology for training or retraining the GA-AIM workforce to make workers comfortable with new technologies before deployment in real-world applications.

Russell Innovation Center for Entrepreneurs

  • LaunchPad AI Innovation Studio: The Russell Innovation Center for Entrepreneurs will create the 5,000-square-foot LaunchPad AI Innovation Studio to provide prototyping and proof of concept development of physical products. Black entrepreneurs will be given access to equipment, training, and mentoring. LaunchPad AI will also be open to AI InVenture teams from Atlanta’s K-12 public schools, with special programs designed for startup mentoring and seed funding for K-12 entrepreneurs.

Technical College System of Georgia (TCSG)

  • AI Manufacturing Technical Workforce Development: As Georgia’s technical college coordinating organization, the TCSG will design, develop, and implement curricula at community colleges that include apprenticeships at AI-MPF and virtual reality modules from Spelman. The TCSG will also provide regional entry points for dual enrollment and traditional students to AI manufacturing technical education at certificate and degree levels. Graduates will have exit points that lead directly to careers in the industry or provide for the continuation of education and higher degree attainment through articulation agreements among GA-AIM members.

With this grant, Tech becomes a finalist for significantly more funding to implement projects that support an industry sector and help communities withstand future economic shocks.

“GA-AIM is in strategic alignment with the EDA’s funding priorities, including manufacturing, workforce development, equity, and technology-based economic development,” said David Bridges, vice president of the Enterprise Innovation Institute at Georgia Tech and co-author of the grant proposal. “With manufacturing employing more than 400,000 people across the state and contributing more than $61 billion in economic activity, it’s critical that we leverage the best ideas and programs through our coalition of partners.”  

###

About the Georgia Institute of Technology
The Georgia Institute of Technology, or Georgia Tech, is a top 10 public research university developing leaders who advance technology and improve the human condition. The Institute offers business, computing, design, engineering, liberal arts, and sciences degrees. Its nearly 44,000 students, representing 50 states and 149 countries, study at the main campus in Atlanta, at campuses in France and China, and through distance and online learning. As a leading technological university, Georgia Tech is an engine of economic development for Georgia, the Southeast, and the nation, conducting more than $1 billion in research annually for government, industry, and society.

About the U.S. Economic Development Administration
The mission of the U.S. Economic Development Administration (EDA) is to lead the federal economic development agenda by promoting competitiveness and preparing the nation's regions for growth and success in the worldwide economy. An agency within the U.S. Department of Commerce, EDA makes investments in economically distressed communities in order to create jobs for U.S. workers, promote American innovation, and accelerate long-term sustainable economic growth.

Writer: Péralte C. Paul I peralte.paul@comm.gatech.edu I 404.316.1210

Media contact: Steven Norris | stephen.norris@comm.gatech.edu| 404.281.3343

News Contact

Péralte C. Paul
404.316.1210

Default Image: Research at Georgia Tech

When cell phones, electric vehicle chargers, or other electronic devices get too hot, performance degrades, and eventually overheating can cause them to shut down or fail. In order to prevent that from happening researchers are working to solve the problem of dissipating heat produced during performance. Heat that is generated in the device during operation has to flow out, ideally with little hinderance to reduce the temperature rise. Often this thermal energy must cross several dissimilar materials during the process and the interface between these materials can cause challenges by impeding heat flow.

A new study from researchers at the Georgia Institute of Technology, Notre Dame, University of California Los Angeles, University of California Irvine, Oak Ridge National Laboratory, and the Naval Research Laboratory observed interfacial phonon modes which only exist at the interface between silicon (Si) and germanium (Ge). This discovery, published in the journal Nature Communications, shows experimentally that decades-old conventional theories for interfacial heat transfer are not complete and the inclusion of these phonon modes are warranted.

“The discovery of interfacial phonon modes suggests that the conventional models of heat transfer at interfaces which only use bulk phonon properties are not accurate,” said the Zhe Cheng, a Ph.D. graduate from Georgia Tech’s George W. Woodruff School of Mechanical Engineering who is now a postdoc at University of Illinois at Urbana-Champaign (UIUC). “There is more space for research at the interfaces. Even though these modes are localized, they can contribute to thermal conductance across interfaces.”

The discovery opens a new pathway for consideration when engineering thermal conductance at interfaces for electronics cooling and other applications where phonons are majority heat carriers at material interfaces.

“These results will lead to great progress in real-world engineering applications for thermal management of power electronics,” said co-author Samuel Graham, a professor in the Woodruff School of Mechanical Engineering at Georgia Tech and new dean of engineering at University of Maryland. “Interfacial phonon modes should exist widely at solid interfaces. The understanding and manipulation of these interface modes will give us the opportunity to enhance thermal conductance across technologically-important interfaces, for example, GaN-SiC, GaN-diamond, β-Ga2O3-SiC, and β-Ga2O3-diamond interfaces.”

Presence of Interfacial Phonon Modes Confirmed in Lab

The researchers observed the interfacial phonon modes experimentally at a high-quality Si-Ge epitaxial interface by using Raman Spectroscopy and high-energy resolution electron energy-loss spectroscopy (EELS). To figure out the role of interfacial phonon modes in heat transfer at interfaces, they used a technique called time-domain thermoreflectance in labs at Georgia Tech and UIUC to determine the temperature-dependent thermal conductance across these interfaces.

They also observed a clean additional peak showing up in Raman Spectroscopy measurements when they measured the sample with Si-Ge interface, which was not observed when they measured a Si wafer and a Ge wafer with the same system. Both the observed interfacial modes and thermal boundary conductance were fully captured by molecular dynamics (MD) simulations and were confined to the interfacial region as predicted by theory.

“This research is the result of great team work with all the collaborators,” said Graham.  “Without this team and the unique tools that were available to us, this work would not have been possible.” 

Moving forward the researchers plan to continue to pursue the measurement and prediction of interfacial modes, increase the understanding of their contribution to heat transfer, and determine ways to manipulate these phonon modes to increase thermal transport. Breakthroughs in this area could lead to better performance in semiconductors used in satellites, 5G devices, and advanced radar systems, among other devices.

The epitaxial Si-Ge samples used in this research were grown at the U.S. Naval Research Lab. The TEM and EELS measurements were done at University of California, Irvine and Oak Ridge National Labs. The MD simulations were performed by the University of Notre Dame. The XRD study was done at UCLA. 

This work is financially supported by U.S. Office of Naval Research under a MURI project. The EELS study at UC Irvine is supported by U.S. Department of Energy. 

Citation: https://doi.org/10.1038/s41467-021-27250-3

About Georgia Institute of Technology

The Georgia Institute of Technology, or Georgia Tech, is a top 10 public research university developing leaders who advance technology and improve the human condition. The Institute offers business, computing, design, engineering, liberal arts, and sciences degrees. Its nearly 44,000 students representing 50 states and 149 countries, study at the main campus in Atlanta, at campuses in France and China, and through distance and online learning. As a leading technological university, Georgia Tech is an engine of economic development for Georgia, the Southeast, and the nation, conducting more than $1 billion in research annually for government, industry, and society.

Contact: 
Ben Wright 
Communications Manager
George W. Woodruff School of Mechanical Engineering
ben.wright@me.gatech.edu 
 

Blue shipping containers
headshot of professor Manpreet Hora
headshot of Ravi Subramanian, professor
headshot of Vinod Singhal, Charles W. Brady Chair

Supply chain disruptions are not new, but the current disruptions have not only been persistent but have also impacted several industries – and consumers – at the same time. The result has ranged from empty shelves at retail stores to prolonged lead times for consumer products and automobiles.

We sat down with three Georgia Tech Scheller College of Business faculty experts in operations management: Vinod Singhal, Charles W. Brady Chair; Manpreet Hora, associate professor; and Ravi Subramanian, professor. The discussion centered around overarching causes, financial ramifications, and multi-pronged approaches to mitigate the impact of supply chain disruptions in the coming months and year. 

1. What caused the supply chain and logistical issues to arise? What effect did Covid-19 play in all of this? Did the influx of stimulus checks and the extension of additional aid to U.S. citizens (rent deferment, etc.) affect the purchase of goods enough to cause the current situation?

All three experts agree there are several factors on both the supply side and the demand side of the supply chain, and logistical challenges that companies and customers are currently facing.

On the supply side, there are issues in global supply chains that are beyond the control of individual companies. A significant one is the congestion at the ports of Los Angeles and Long Beach in the U.S. Nearly 40 percent of imports into the U.S. flow through these two ports. There are stranded containers that have not been unloaded due to labor shortages, limited unloading capacity, and warehouse space constraints.

For example, a CBS news report on November 11, 2021, indicated that at the ports of Los Angeles and Long Beach, about 80 ships carrying more than half a million containers were waiting to unload. Clearing this backlog will take some time. Another related issue that has added to the congestion is the growing number of empty containers that are sitting on ports to be returned back to exporters.

The congestion at ports is being further exacerbated by trucker shortages that could pose a more persistent and long-term challenge for supply chains.

“Moving products from ports to distribution centers, manufacturing plants, and further downstream to retailers was already a concern for many companies even before the pandemic. Now the combination of port congestion and trucker shortage is further delaying the process of bringing products to the right place at the right time,” said Hora.

Shortages of critical components, such as semiconductor chips, have created additional delays for a range of industries. Shutdowns in chip production during the early stages of the pandemic, coupled with increased demand for products such as computers, smartphones, and automobiles has resulted in fierce competition for acquiring chips across industries. For example, the professors noted that during the initial period of the Covid-19 pandemic, semiconductor companies prioritized chip manufacturing to meet the increasing demand for consumer electronics. This, in turn, diverted supply away from automotive production, resulting in substantial delays in cars rolling off assembly lines

The pandemic either amplified the above-mentioned supply chain and logistical issues or brought in unexpected new ones. It necessitated the closure of borders at the national level, and of plants and warehouses at the company level. These closures, in the initial months of the pandemic, followed by new requirements such as social distancing during the opening of facilities affected and slowed down production, warehousing, distribution, and transportation of products.

On the demand side, explained Subramanian, two phenomena occurred that have led to a surge in demand for goods that were already in short supply.

First, during the pandemic, many people were working from home. This curtailed spending on travel, vacations, and demand for experiential goods and services. People had more disposable income, which they diverted to consumer products that were already in short supply.

Second, the global economy and the US, in particular have been turbocharged by trillions of dollars in stimulus during the pandemic. This stimulus, while necessary to deal with the hardships during the pandemic, enhanced the surge in demand for products.

2. Why are some retailers able to deliver goods without an issue?

“Many large retailers, including Walmart Inc., Home Depot Inc., and Target Corp., do not seem to have supply chain and product shortage issues like their counterparts, because they ordered and took delivery of goods earlier than usual this year. They have not only built-up inventories but have enhanced their inventory management practices. Some retailers have also chartered their own ships to counteract delays in transportation,” said Singhal.

They have also moved the unloading of their goods from the ports on the west coast to other ports in the U.S. that are less congested. These retailers have used their clout and deep pockets to get suppliers and logistics companies to prioritize their orders. Their far-flung supply chain networks can identify and work with several suppliers to find options to source items that are out of stock.

3. What are the financial ramifications to the U.S. and to the world for this supply chain issue?

The professors note that large companies have used their clout to deal with the current supply chain issues. Although their costs of procuring supplies have increased, they may be able to pass on some of the cost increase to customers. Some of these companies may see an increase in total sales and total profits in nominal terms although they may experience thinner profit margins. The stock market seems to have incorporated these factors in the valuations and the rising stock market suggests that large companies are expected to do fine financially. For example, the Dow Jones Index has jumped 18 percent this year, S&P 500 is up 25 percent, and Nasdaq has risen 24 percent.

The financial ramifications to smaller retailers and manufacturing firms may be quite negative. As Subramanian explained, these firms do not have the clout and financial resources to work around the supply issues.  Often their sales during the holiday season are critically dependent on receiving a container or two of goods from overseas suppliers. Given the long and uncertain transportation and delivery times, and the high cost of transportation, many small firms may not be able to receive supplies in time for the holiday season and may be left holding unsold inventory or unfinished products. Overall, small firms may take a big hit from the current supply chain issues.

4. Are there any additional issues that consumers may face that they may not be aware of? How will the shortage of goods to retailers affect consumers shopping during the holidays? Is there anything individual consumers can do to help solve the problem?

Consumers can do certain things so that they are not disappointed, said the panel. They should start shopping earlier, expect to pay closer to full price on many products, and not wait for promotions or discounts to make their purchases. They will need to be flexible in their shopping habits and look for substitute products if their desired products are not available. Consumers may also want to prioritize their shopping decisions – for example, ensuring they have the gifts for young children who expect Santa to deliver irrespective of supply chain issues! Likewise, for older parents and relatives, for whom the holiday season is a very special time.  For others, they may want to consider giving gift cards.

5. When do you think this issue will be resolved and how?

“Supply chains getting back to normal will be contingent upon the nature of the underlying supply chain issues. Shipping and retail executives indicate that they expect the West Coast port backlogs to clear in early 2022, when the Lunar New Year shuts many factories for a week in February, thus slowing output and shipments from Asia,” said Singhal.  However, chip shortages may last until 2022 or even extend into 2023. Many chip manufacturers have announced plans to significantly increase their level of capital expenditure but bringing new capacity online can take several years.

This storm of collective issues has brought the importance of supply chain resilience to the forefront. Companies emerging from the pandemic are revisiting or will have to revisit their past approaches to managing supply chains.

Having flexibility and slack in supply chains has been a persistent strategy for several companies but this strategy will now need to be more holistic. For example, companies will need to re-think where to source their critical and irreplaceable components. Companies are already deliberating to not only near-shore suppliers of their critical components but also expand this supply base. This may also entail carrying more inventory of such components to meet demand variability and hedge against supply chain disruptions. Another development is manufacturers vertically integrating to design and produce critical components in-house.

Even before the pandemic, companies were investing in technology to digitize their supply chains. This long-term imperative will be prioritized even more as companies aspire for more transparency and traceability of products in their supply chains. Moreover, advanced automation in manufacturing plants and warehousing could ease some of the pain of labor shortages.

“Despite the current supply chain issues, we believe that supply chains will remain global and complex, but there will be renewed thinking in companies to recognize that Black Swan events such as the Covid-19 pandemic can create a multitude of interrelated and cascading supply chain issues that have serious financial implications. And companies will need to blend flexibility, adaptability, and efficiency to develop capabilities to mitigate impacts and remain resilient during such supply chain disruptions,” stated Hora.

News Contact

Lorrie Burroughs

Student of Shimeng Yu at a probe station

With holiday shopping deadlines looming, consumers cannot escape the impact of the global microelectronic chip shortage. From daily news reports about manufacturers unable to complete orders due to the lack of chips, to “out of stock” messages across websites on popular electronics items, one of the impacts of COVID was to lay bare the massive importance of the microelectronic chip in daily modern life, and how a single-location centered manufacturing nexus can upend the consumer market on a massive scale. The combination of these real-world impacts on supply chains, as well as the need to localize semiconductor and chip manufacturing gave Congress the impetus to pass the “Creating Helpful Incentives to Produce Semiconductors for America Act (CHIPS)”. CHIPS seeks to increase investments and incentives to support U.S. semiconductor manufacturing, research and development, and supply chain security.

The Georgia Institute of Technology was the first university to offer a comprehensive curriculum on microelectronics and microsystems design and packaging and, currently, numerous faculty at Georgia Tech are widely known for their work in semiconductor and microelectronics technologies. In December of 2021 Georgia Tech researchers will again showcase how their pushes the boundaries of microelectronics technologies at the IEEE International Electron Devices Meeting (IEDM).

The School of Electrical and Computer Engineering research teams of Assistant Professor Asif Khan, partnering with Dan Fielder Professor Muhannad Bakir, and Associate Professor Shimeng Yu, partnering with Professor Sung-Kyu Lim and Assistant Professor Shaolan Li, have dominated the 2021 IEDM presentation line-up with a total of 8 accepted papers. With topics ranging from ferroelectric materials for memory, new advances in ALD process, and in-memory computing and 3D reconfigurable architectures, the research presented by these teams is at the cutting-edge of advancing computing power and consumer electronics. In addition to the research presentations, Electrical and Computing Engineering Faculty & Director of the 3D Systems Packaging Research Center at GT will be presenting a short course session on devoted to “Heterogenous Integration Using Chiplets & Advanced Packaging”

Noting the timely nature of these research advancements, Arijit Raychowdhory; Professor and Steve W. Chaddick School Chair in Electrical and Computer Engineering noted, “IEDM is a premier conference in the area of semiconductor devices. Such a strong performance by GT ECE exemplifies the strength of our program, the ingenuity of our students and the innovation driven by our world-class faculty. Sincere congratulations to Professors Khan, Yu Bakir, Lim and Li for their pioneering research in semiconductor logic and memory technologies, that are critical for our nation and our industries.” 

Asif Khan is an assistant professor in the School of Electrical and Computer Engineering at the Georgia Tech. He received his Ph.D. in electrical engineering and computer sciences from the University of California, Berkeley in 2015. His work led to the first experimental proof-of-concept demonstration of the negative capacitance effect in ferroelectric oxides. His group at Georgia Tech conceptualizes and fabricates electronic devices that leverage interesting physics and novel phenomena in emerging materials (such as ferroelectrics, antiferroelectrics and strongly correlated systems) to overcome the “fundamental” limits in computation and to address the most pressing challenges in electronics and the semiconductor industry.

Shimeng Yu is currently an associate professor in the School of Electrical and Computer Engineering at the Georgia Tech. He received the B.S. degree in microelectronics from Peking University in 2009, and the M.S. degree and Ph.D. degree in electrical engineering from Stanford University in 2011 and 2013, respectively. From 2013 to 2018, he was an assistant professor at Arizona State University. Prof. Yu’s research interests are the semiconductor devices and integrated circuits for energy-efficient computing systems. His research expertise is on the emerging non-volatile memories for applications such as deep learning accelerator, in-memory computing, 3D integration, and hardware security.

Muhannad S. Bakir is the Dan Fielder Professor in the School of Electrical and Computer Engineering at Georgia Tech.  Dr. Bakir and his research group have received more than thirty paper and presentation awards including six from the IEEE Electronic Components and Technology Conference (ECTC), four from the IEEE International Interconnect Technology Conference (IITC), one from the IEEE Custom Integrated Circuits Conference (CICC), and two from the IEEE Transactions on Components Packaging and Manufacturing Technology (TCPMT). Muhannad S. Bakir received the B.E.E. degree from Auburn University, Auburn, AL, in 1999 and the M.S. and Ph.D. degrees in electrical and computer engineering from the Georgia Tech in 2000 and 2003, respectively. His research interests include, heterogeneous microsystem design and integration, including 2.5D and 3D ICs and packaging, electrical and photonic interconnects, and embedded cooling technologies.

Sung Kyu Lim received B.S. (1994), M.S. (1997), and Ph.D. (2000) degrees all from the Computer Science Department at UCLA. During 2000-2001, he was a post-doctoral scholar at UCLA, and a senior engineer at Aplus Design Technologies, Inc. Lim joined the School of Electrical and Computer Engineering at Georgia Institute of Technology an assistant professor. He is currently the director of the GTCAD (Georgia Tech Computer Aided Design) Laboratory and focuses on VLSI and 3D circuit architecture and packaging.

Shaolan Li received his B.Eng. degree with highest honor from the Hong Kong University of Science and Technology (HKUST) in 2012, and his Ph.D. from UT Austin in 2018, all in electrical engineering. Prior joining Georgia Tech as an assistant professor in 2019, he was a post-doctoral fellow in the Department of Electrical and Computer Engineering at UT Austin from 2018-2019. He also held intern positions in Broadcom Ltd. in Sunnyvale, California, and NXP in Tempe, Arizona during 2013-2014. His research interests are broadly in analog, mixed-signal, and RF integrated circuits. His expertise is in high-performance data converters, ultra-low-power low-cost sensor interface, and novel analog mixed-signal architectures for design automation.

The IEEE International Electron Devices Meeting (IEDM) is the world’s preeminent forum for reporting technological breakthroughs in the areas of semiconductor and electronic device technology, design, manufacturing, physics, and modeling. IEDM is the flagship conference for nanometer-scale CMOS transistor technology, advanced memory, displays, sensors, MEMS devices, novel quantum and nano-scale devices and phenomenology, optoelectronics, devices for power and energy harvesting, high-speed devices, as well as process technology and device modeling and simulation. Georgia Tech research teams have a strong track of record in IEDM publications in the recent years, including 8, 4, 9 and 7 papers presented in IEDM 2018, 2019, 2020 and 2021, respectively.

 

- Christa M. Ernst

News Contact

Christa M. Ernst - Interdisciplinary Research Communications Program Manager
Topics:  Materials | Nanotechnology | Robotics
Georgia Institute of Technology| christa.ernst@research.gatech.edu

Lance Johnson, advanced manufacturing engineering manager at Moog
Andrew Dugenske, director of the Factory Information Systems Center and principal research engineer at GTMI

There’s a lot more to running a factory than manufacturing. Companies must also maximize the materials they use, minimize a wide range of costs, and reduce or eliminate factory floor time delays—while running many factories with a just in time inventory approach. So, when Moog, Inc., the well-known maker of motion control components for aircraft, entertainment, industry, defense, and the medical industries, wanted to keep their factories running at peak condition, they knew the engineers at the Georgia Tech Manufacturing Institute (GTMI) were the ones to call on.

“Tech brings a strong expertise in applying their research knowledge to areas that are important to us, like vibration research, telemetry, and they know how to apply that knowledge to manufacturing,” said Lance Johnson, advanced manufacturing engineering manager at Moog. “What’s more, they know how we think, and they know what we need."

Having partnered for nearly a decade, lately, the two institutions have been collaborating in the arena of the Internet of Things for Manufacturing to help Moog keep abreast of the health, performance, and utilization of its assembly lines.

“GTMI’s work allows us to really understand the health and productivity of our machines, and more fundamentally, it allows us to optimize our processes, no matter what component we’re assembling at the time,” said Johnson.

For example, a company may want to run its machines at a high pace, but if they don’t understand how that would wear on the parts, they may cycle through them too quickly, or even worse, must shut the line down for maintenance at an inopportune time. If they go the opposite route and play it safe, they can minimize parts fatigue but not produce enough. They lose money in either scenario.

“You don’t want to have to shut down the line for repairs while you’re in the middle of creating parts that are critical to the consumer, nor do you want to push too hard and make bad parts,” explained Johnson.

Using its expertise and software to analyze the machines' vibrations and physical stress, GTMI helps Moog operate its lines at peak efficiency. This helps Moog keep its assembly lines healthy and maintains the quality of their wares.

The project involves using GTMI’s architecture as a universal translator to convert all of the assembly lines’ various protocols to a standard one. This ensures that all areas of the factory can talk to each other, which helps them cut costs.

“Integration costs to implement factory information systems are often underestimated, yet unexpected costs are a real pain point for companies,” said Andrew Dugenske, director of the Factory Information Systems Center and principal research engineer at GTMI. “Our decoupled digital architecture provides a clear advantage by reducing integration costs.”

When it comes to understanding the most complex issues in today’s manufacturing world, GTMI is on top.

“We’re an advanced company in terms of our manufacturing capabilities,” said Johnson. “Their work is invaluable in helping us bridge the divide between the classical core research and the new research being done on vibration. They can contextualize it to the areas that are important to us.”

One thing that distinguishes GTMI from other centers, said Johnson, is that they’re approachable. “They're easy to talk to and understand how to contextualize the research into solutions that work on the issues that we face,” said Johnson.

Another distinction is the insightful interns GTMI provides. "It's really amazing. The interns who come out of Georgia Tech already understand the problems we’re working on because they already understand manufacturing. So, when they arrive, they're able to hit the ground running,” he explained.

Nathan Devol was working at Hubble Lighting when he decided he was missing the research aspect of his career, so he decided to go back to school to get his Ph.D. at Tech. He’s been working with Moog since he arrived on campus two years ago.

"One of the things I've liked about working with Moog is that the problems we’re working on are continually evolving,” said Devol. “Another thing is that we’re not just working on tightly controlled projects, like one often does in a research environment. The solutions we deliver have to be able to scale up to work at the factory level.”

Devol experienced this when he was monitoring the vibrations of manufacturing equipment. The trouble came when they were collecting vibration data and sending it up to the cloud to process and observe it.

“We had this problem where we’re sampling the vibration data at around 10,000 samples per second, and the cloud just couldn’t handle it, so there were huge latencies,” said Devol. “I started looking and found that if we compressed the data before sending it to the cloud, we would be able to work with it without the backlog.”

It worked beautifully.

“They’re doing a great job,” said Johnson. “I really like how they can get up to speed quickly with what we’re doing and apply the research and problems they’re working on at Tech to our problems in manufacturing.”

It’s a win-win relationship that promises to deliver benefits to both institutions for years to come.

 

About Moog Inc.
Moog Inc. is a worldwide designer, manufacturer, and integrator of precision control components and systems. Moog’s high-performance systems control military and commercial aircraft, satellites and space vehicles, launch vehicles, missiles, automated industrial machinery, and marine and medical equipment. Additional information about the company can be found at www.moog.com.

 

Story by David Terraso

News Contact

Walter Rich

In the last few years, mechanically assistive exosuits, long depicted in works of popular science fiction and film, have finally started to see commercial deployment, according to Aaron Young, professor in the George W. Woodruff School of Mechanical Engineering at Georgia Tech. Most of these exosuits have a so-called passive design, assisting the wearer with unpowered elements like springs. 

Active exosuits that incorporate electronics and powered motors are yet to be broadly applied. They tend to be big and heavy, and rely on rigid exoskeletons to transfer weight from body to ground. Exoskeletons add a great deal of stiffness, as well, Young said. Putting on most active exosuits is a little like becoming one with a forklift, restricting a wearer to lifting weights in a vertical plane.

For all these reasons, Young’s Asymmetric Back eXosuit (ABX) described in the October 5 issue of IEEE Transactions on Robotics is highly non-standard. There’s no exoskeleton, no rigid structure, nothing that makes contact with the floor. If the wearer is just standing there, it does nothing except for adding 14 pounds to their legs. But if they raise their body from a leaning over position, it makes a somewhat frantic noise: that is the sound of the ABX helping them rotate their torso, helping them twist. 

Although most active exosuits support vertical lifts, rotating and twisting movements are also ubiquitous, especially in certain fields of manual labor like garbage collection and baggage handling. In many cases, these motions can be awkward and strenuous, leading to work-related injuries as well as back pain, according to Young. Back pain, in turn, is directly correlated with the strength of compressive forces and shear forces that are applied to the spine.

In designing their exosuit, the researchers sought a way to reduce these loads on the spinal joints. Putting it on looks a little like donning a futuristic backpack. Two motors are first strapped onto the back of each upper thigh. These motors are then connected to the back of the opposite shoulders, each with their own cable, making for two cables that diagonally overlap. The exosuit provides assistance by applying tension to the cables when it detects a wearer rise from a bending posture.

“It's definitely a different sensation than a sort of standard exoskeleton. It's not your standard design,” said Young. 

Because the diagonal cables have a component of motion that is horizontal, they exert a pull on the torso that can aid in twisting it from side to side. In tests, the researchers showed that when a wearer of the ABX swung a weight from the ground to one side, the exosuit reduced their back muscle activations by an average of 16%, as measured by electromyography (EMG) sensors. The exosuit also provided a 37% reduction in back muscle exertion when a wearer lifted weights symmetrically, straight off the ground – an assistance level comparable to more rigid designs. 

“People definitely felt like the technology is assisting them, which is great. And we did see the concurrent EMG reduction,” said Young. “I think it’s a great first step.”

In a sense, wearing the exosuit is almost like strapping two additional muscles onto the body – unconventional muscles, which run directly from back to leg. Interestingly, it is the positioning of these muscles rather than their brute strength that makes them functional, said Young.

The motors pull the cables with much less power than the muscles in the body. However, the cables are positioned much further away from the joints. Through this positioning, the cables obtain greater leverage and mechanical advantage, allowing the wearer to reduce their overall muscular output and hence the load that they place on their spine. (Spinal loading was not directly measured in the study.)

Aside from its overall performance, it is the flexible, asymmetric nature of the suit that really makes it unique, Young said. There are currently no other active exosuits that provide assistance for twisting and rotating through a comparable range of motion. While other exosuits also use cables, none have arranged them along diagonal lines.

Young is currently seeking collaborations with industry partners to further develop the exosuit. In future work, he sees its control system as a point to improve. Currently, when a person raises their torso from a lowered position, the cables simply pull with constant tension. But it should be possible to make the system detect different actions of the wearer and adjust its pull in response.

References

J. M. Li, D. D. Molinaro, A. S. King, A. Mazumdar and A. J. Young, "Design and Validation of a Cable-Driven Asymmetric Back Exosuit," in IEEE Transactions on Robotics, doi: 10.1109/TRO.2021.3112280.

About Georgia Tech

The Georgia Institute of Technology, or Georgia Tech, is a top 10 public research university developing leaders who advance technology and improve the human condition. The Institute offers business, computing, design, engineering, liberal arts, and sciences degrees. Its nearly 40,000 students representing 50 states and 149 countries, study at the main campus in Atlanta, at campuses in France and China, and through distance and online learning. As a leading technological university, Georgia Tech is an engine of economic development for Georgia, the Southeast, and the nation, conducting more than $1 billion in research annually for government, industry, and society.

News Contact

Mordechai Rorvig
Senior Science Writer
Georgia Institute of Technology