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Adaptive smart glove from MIT CSAIL researchers can send tactile feedback to teach users new skills, guide robots with more precise manipulation, and help train surgeons and pilots.

You’ve likely met someone who identifies as a visual or auditory learner, but others absorb knowledge through a different modality: touch. Being able to understand tactile interactions is especially important for tasks such as learning delicate surgeries and playing musical instruments, but unlike video and audio, touch is difficult to record and transfer.

To tap into this challenge, researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) and elsewhere developed an embroidered smart glove that can capture, reproduce, and relay touch-based instructions. To complement the wearable device, the team also developed a simple machine-learning agent that adapts to how different users react to tactile feedback, optimizing their experience. The new system could potentially help teach people physical skills, improve responsive robot teleoperation, and assist with training in virtual reality.

Will I be able to play the piano?
To create their smart glove, the researchers used a digital embroidery machine to seamlessly embed tactile sensors and haptic actuators (a device that provides touch-based feedback) into textiles. This technology is present in smartphones, where haptic responses are triggered by tapping on the touch screen. For example, if you press down on an iPhone app, you’ll feel a slight vibration coming from that specific part of your screen. In the same way, the new adaptive wearable sends feedback to different parts of your hand to indicate optimal motions to execute different skills.

The smart glove could teach users how to play the piano, for instance. In a demonstration, an expert was tasked with recording a simple tune over a section of keys, using the smart glove to capture the sequence by which they pressed their fingers to the keyboard. Then, a machine-learning agent converted that sequence into haptic feedback, which was then fed into the students’ gloves to follow as instructions. With their hands hovering over that same section, actuators vibrated on the fingers corresponding to the keys below. The pipeline optimizes these directions for each user, accounting for the subjective nature of touch interactions.

“Humans engage in a wide variety of tasks by constantly interacting with the world around them,” says Yiyue Luo MS ’20, lead author of the paper, PhD student in MIT’s Department of Electrical Engineering and Computer Science (EECS), and CSAIL affiliate. “We don’t usually share these physical interactions with others. Instead, we often learn by observing their movements, like with piano-playing and dance routines.

“The main challenge in relaying tactile interactions is that everyone perceives haptic feedback differently,” adds Luo. “This roadblock inspired us to develop a machine-learning agent that learns to generate adaptive haptics for individuals’ gloves, introducing them to a more hands-on approach to learning optimal motion.”

The wearable system is customized to fit the specifications of a user’s hand via a digital fabrication method. A computer produces a cutout based on individuals’ hand measurements, then an embroidery machine stitches the sensors and haptics in. Within 10 minutes, the soft, fabric-based wearable is ready to wear. Initially trained on 12 users’ haptic responses, its adaptive machine-learning model only needs 15 seconds of new user data to personalize feedback.

In two other experiments, tactile directions with time-sensitive feedback were transferred to users sporting the gloves while playing laptop games. In a rhythm game, the players learned to follow a narrow, winding path to bump into a goal area, and in a racing game, drivers collected coins and maintained the balance of their vehicle on their way to the finish line. Luo’s team found that participants earned the highest game scores through optimized haptics, as opposed to without haptics and with unoptimized haptics.

“This work is the first step to building personalized AI agents that continuously capture data about the user and the environment,” says senior author Wojciech Matusik, MIT professor of electrical engineering and computer science and head of the Computational Design and Fabrication Group within CSAIL. “These agents then assist them in performing complex tasks, learning new skills, and promoting better behaviors.”

Bringing a lifelike experience to electronic settings
In robotic teleoperation, the researchers found that their gloves could transfer force sensations to robotic arms, helping them complete more delicate grasping tasks. “It’s kind of like trying to teach a robot to behave like a human,” says Luo. In one instance, the MIT team used human teleoperators to teach a robot how to secure different types of bread without deforming them. By teaching optimal grasping, humans could precisely control the robotic systems in environments like manufacturing, where these machines could collaborate more safely and effectively with their operators.

“The technology powering the embroidered smart glove is an important innovation for robots,” says Daniela Rus, the Andrew (1956) and Erna Viterbi Professor of Electrical Engineering and Computer Science at MIT, CSAIL director, and author on the paper. “With its ability to capture tactile interactions at high resolution, akin to human skin, this sensor enables robots to perceive the world through touch. The seamless integration of tactile sensors into textiles bridges the divide between physical actions and digital feedback, offering vast potential in responsive robot teleoperation and immersive virtual reality training.”

Likewise, the interface could create more immersive experiences in virtual reality. Wearing smart gloves would add tactile sensations to digital environments in video games, where gamers could feel around their surroundings to avoid obstacles. Additionally, the interface would provide a more personalized and touch-based experience in virtual training courses used by surgeons, firefighters, and pilots, where precision is paramount.

While these wearables could provide a more hands-on experience for users, Luo and her group believe they could extend their wearable technology beyond fingers. With stronger haptic feedback, the interfaces could guide feet, hips, and other body parts less sensitive than hands.

Luo also noted that with a more complex artificial intelligence agent, her team's technology could assist with more involved tasks, like manipulating clay or driving an airplane. Currently, the interface can only assist with simple motions like pressing a key or gripping an object. In the future, the MIT system could incorporate more user data and fabricate more conformal and tight wearables to better account for how hand movements impact haptic perceptions.

Luo, Matusik, and Rus authored the paper with EECS Microsystems Technology Laboratories Director and Professor Tomás Palacios; CSAIL members Chao Liu, Young Joong Lee, Joseph DelPreto, Michael Foshey, and professor and principal investigator Antonio Torralba; Kiu Wu of LightSpeed Studios; and Yunzhu Li of the University of Illinois at Urbana-Champaign.

The work was supported, in part, by an MIT Schwarzman College of Computing Fellowship via Google and a GIST-MIT Research Collaboration grant, with additional help from Wistron, Toyota Research Institute, and Ericsson.

Freezing is one of the most common and debilitating symptoms of Parkinson’s disease, a neurodegenerative disorder that affects more than 9 million people worldwide. When individuals with Parkinson’s disease freeze, they suddenly lose the ability to move their feet, often mid-stride, resulting in a series of staccato stutter steps that get shorter until the person stops altogether. These episodes are one of the biggest contributors to falls among people living with Parkinson’s disease.

Today, freezing is treated with a range of pharmacological, surgical or behavioral therapies, none of which are particularly effective. What if there was a way to stop freezing altogether?

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and the Boston University Sargent College of Health & Rehabilitation Sciences have used a soft, wearable robot to help a person living with Parkinson’s walk without freezing. The robotic garment, worn around the hips and thighs, gives a gentle push to the hips as the leg swings, helping the patient achieve a longer stride.

The device completely eliminated the participant’s freezing while walking indoors, allowing them to walk faster and further than they could without the garment’s help.

“We found that just a small amount of mechanical assistance from our soft robotic apparel delivered instan-taneous effects and consistently improved walking across a range of conditions for the individual in our study,” said Conor Walsh, the Paul A. Maeder Professor of Engineering and Applied Sciences at SEAS and co-corresponding author of the study.

The research demonstrates the potential of soft robotics to treat this frustrating and potentially dangerous symptom of Parkinson’s disease and could allow people living with the disease to regain not only their mobility but their independence.

For over a decade, Walsh’s Biodesign Lab at SEAS has been developing assistive and rehabilitative robotic technologies to improve mobility for individuals’ post-stroke and those living with ALS or other diseases that impact mobility. Some of that technology, specifically an exosuit for post-stroke gait retraining, received support from the Wyss Institute for Biologically Inspired Engineering, and Harvard’s Office of Technology Development coordinated a license agreement with ReWalk Robotics to commercialize the technology.

In 2022, SEAS and Sargent College received a grant from the Massachusetts Technology Collaborative to support the development and translation of next-generation robotics and wearable technologies. The research is centered at the Move Lab, whose mission is to support advances in human performance enhancement with the collaborative space, funding, R&D infrastructure, and experience necessary to turn promising research into mature technologies that can be translated through collaboration with industry partners. This research emerged from that partnership.

“Leveraging soft wearable robots to prevent freezing of gait in patients with Parkinson’s required a collaboration between engineers, rehabilitation scientists, physical therapists, biomechanists and apparel designers,” said Walsh, whose team collaborated closely with that of Terry Ellis,  Professor and Physical Therapy Department Chair and Director of the Center for Neurorehabilitation at Boston University.

Leveraging soft wearable robots to prevent freezing of gait in patients with Parkinson’s required a collaboration between engineers, rehabilitation scientists, physical therapists, biomechanists and apparel designers.

The team spent six months working with a 73-year-old man with Parkinson’s disease, who — despite using both surgical and pharmacologic treatments — endured substantial and incapacitating freezing episodes more than 10 times a day, causing him to fall frequently. These episodes prevented him from walking around his community and forced him to rely on a scooter to get around outside.

In previous research, Walsh and his team leveraged human-in-the-loop optimization to demonstrate that a soft, wearable device could be used to augment hip flexion and assist in swinging the leg forward to provide an efficient approach to reduce energy expenditure during walking in healthy individuals.

Here, the researchers used the same approach but to address freezing. The wearable device uses cable-driven actuators and sensors worn around the waist and thighs. Using motion data collected by the sensors, algorithms estimate the phase of the gait and generate assistive forces in tandem with muscle movement.

The effect was instantaneous. Without any special training, the patient was able to walk without any freezing indoors and with only occasional episodes outdoors. He was also able to walk and talk without freezing, a rarity without the device.

“Our team was really excited to see the impact of the technology on the participant’s walking,” said Jinsoo Kim, former PhD student at SEAS and co-lead author on the study.

During the study visits, the participant told researchers: “The suit helps me take longer steps and when it is not active, I notice I drag my feet much more. It has really helped me, and I feel it is a positive step forward. It could help me to walk longer and maintain the quality of my life.”

“Our study participants who volunteer their time are real partners,” said Walsh. “Because mobility is difficult, it was a real challenge for this individual to even come into the lab, but we benefited so much from his perspective and feedback.”

The device could also be used to better understand the mechanisms of gait freezing, which is poorly understood.

“Because we don’t really understand freezing, we don’t really know why this approach works so well,” said Ellis. “But this work suggests the potential benefits of a ’bottom-up’ rather than ’top-down’ solution to treating gait freezing. We see that restoring almost-normal biomechanics alters the peripheral dynamics of gait and may influence the central processing of gait control.”

The research was co-authored by Jinsoo Kim, Franchino Porciuncula, Hee Doo Yang, Nicholas Wendel, Teresa Baker and Andrew Chin. Asa Eckert-Erdheim and Dorothy Orzel also contributed to the design of the technology, as well as Ada Huang, and Sarah Sullivan managed the clinical research. It was supported by the National Science Foundation under grant CMMI-1925085; the National Institutes of Health under grant NIH U01 TR002775; and the Massachusetts Technology Collaborative, Collaborative Research and Development Matching Grant.

The low-cost FibeRobo, which is compatible with existing textile manufacturing techniques, could be used in adaptive performance wear or compression garments.

Researchers from MIT and Northeastern University developed a liquid crystal elastomer fiber that can change its shape in response to thermal stimuli. The fiber, which is fully compatible with existing textile manufacturing machinery, could be used to make morphing textiles, like a jacket that becomes more insulating to keep the wearer warm when temperatures drop.

Instead of needing a coat for each season, imagine having a jacket that would dynamically change shape so it becomes more insulating to keep you warm as the temperature drops.
A programmable, actuating fiber developed by an interdisciplinary team of MIT researchers could someday make this vision a reality. Known as FibeRobo, the fiber contracts in response to an increase in temperature, then self-reverses when the temperature decreases, without any embedded sensors or other hard components.

The low-cost fiber is fully compatible with textile manufacturing techniques, including weaving looms, embroidery, and industrial knitting machines, and can be produced continuously by the kilometer. This could enable designers to easily incorporate actuation and sensing capabilities into a wide range of fabrics for myriad applications.

The fibers can also be combined with conductive thread, which acts as a heating element when electric current runs through it. In this way, the fibers actuate using electricity, which offers a user digital control over a textile’s form. For instance, a fabric could change shape based on any piece of digital information, such as readings from a heart rate sensor.

“We use textiles for everything. We make planes with fiber-reinforced composites, we cover the International Space Station with a radiation-shielding fabric, we use them for personal expression and performance wear. So much of our environment is adaptive and responsive, but the one thing that needs to be the most adaptive and responsive — textiles — is completely inert,” says Jack Forman, a graduate student in the Tangible Media Group of the MIT Media Lab, with a secondary affiliation at the Center for Bits and Atoms, and lead author of a paper on the actuating fiber.

He is joined on the paper by 11 other researchers at MIT and Northeastern University, including his advisors, Professor Neil Gershenfeld, who leads the Center for Bits and Atoms, and Hiroshi Ishii, the Jerome B. Wiesner Professor of Media Arts and Sciences and director of the Tangible Media Group. The research will be presented at the ACM Symposium on User Interface Software and Technology.

Morphing materials
The MIT researchers wanted a fiber that could actuate silently and change its shape dramatically, while being compatible with common textile manufacturing procedures. To achieve this, they used a material known as liquid crystal elastomer (LCE).

A liquid crystal is a series of molecules that can flow like liquid, but when they’re allowed to settle, they stack into a periodic crystal arrangement. The researchers incorporate these crystal structures into an elastomer network, which is stretchy like a rubber band.

As the LCE material heats up, the crystal molecules fall out of alignment and pull the elastomer network together, causing the fiber to contract. When the heat is removed, the molecules return to their original alignment, and the material to its original length, Forman explains.

By carefully mixing chemicals to synthesize the LCE, the researchers can control the final properties of the fiber, such as its thickness or the temperature at which it actuates.

They perfected a preparation technique that creates LCE fiber which can actuate at skin-safe temperatures, making it suitable for wearable fabrics.

“There are a lot of knobs we can turn. It was a lot of work to come up with this process from scratch, but ultimately it gives us a lot of freedom for the resulting fiber,” he adds.
However, the researchers discovered that making fiber from LCE resin is a finicky process. Existing techniques often result in a fused mass that is impossible to unspool.

Researchers are also exploring other ways to make functional fibers, such as by incorporating hundreds of microscale digital chips into a polymer, utilizing an activated fluidic system, or including piezoelectric material that can convert sound vibrations into electrical signals.

Fiber fabrication
Forman built a machine using 3D-printed and laser-cut parts and basic electronics to overcome the fabrication challenges. He initially built the machine as part of the graduate-level course MAS.865 (Rapid-Prototyping of Rapid-Prototyping Machines: How to Make Something that Makes [almost] Anything).

To begin, the thick and viscous LCE resin is heated, and then slowly squeezed through a nozzle like that of a glue gun. As the resin comes out, it is cured carefully using UV lights that shine on both sides of the slowly extruding fiber.

If the light is too dim, the material will separate and drip out of the machine, but if it is too bright, clumps can form, which yields bumpy fibers.

Then the fiber is dipped in oil to give it a slippery coating and cured again, this time with UV lights turned up to full blast, creating a strong and smooth fiber. Finally, it is collected into a top spool and dipped in powder so it will slide easily into machines for textile manufacturing.
From chemical synthesis to finished spool, the process takes about a day and produces approximately a kilometer of ready-to-use fiber.

“At the end of the day, you don’t want a diva fiber. You want a fiber that, when you are working with it, falls into the ensemble of materials — one that you can work with just like any other fiber material, but then it has a lot of exciting new capabilities,” Forman says.

Creating such a fiber took a great deal of trial and error, as well as the collaboration of researchers with expertise in many disciplines, from chemistry to mechanical engineering to electronics to design.

The resulting fiber, called FibeRobo, can contract up to 40 percent without bending, actuate at skin-safe temperatures (the skin-safe version of the fiber contracts up to about 25 percent), and be produced with a low-cost setup for 20 cents per meter, which is about 60 times cheaper than commercially available shape-changing fibers.

The fiber can be incorporated into industrial sewing and knitting machines, as well as nonindustrial processes like hand looms or manual crocheting, without the need for any process modifications.
The MIT researchers used FibeRobo to demonstrate several applications, including an adaptive sports bra made by embroidery that tightens when the user begins exercising.

They also used an industrial knitting machine to create a compression jacket for Forman’s dog, whose name is Professor. The jacket would actuate and “hug” the dog based on a Bluetooth signal from Forman’s smartphone. Compression jackets are commonly used to alleviate the separation anxiety a dog can feel while its owner is away.

In the future, the researchers want to adjust the fiber’s chemical components so it can be recyclable or biodegradable. They also want to streamline the polymer synthesis process so users without wet lab expertise could make it on their own.

Forman is excited to see the FibeRobo applications other research groups identify as they build on these early results. In the long run, he hopes FibeRobo can become something a maker could buy in a craft store, just like a ball of yarn, and use to easily produce morphing fabrics.

“LCE fibers come to life when integrated into functional textiles. It is particularly fascinating to observe how the authors have explored creative textile designs using a variety of weaving and knitting patterns,” says Lining Yao, the Cooper-Siegel Associate Professor of Human Computer Interaction at Carnegie Mellon University, who was not involved with this work.

This research was supported, in part, by the William Asbjornsen Albert Memorial Fellowship, the Dr. Martin Luther King Jr. Visiting Professor Program, Toppan Printing Co., Honda Research, Chinese Scholarship Council, and Shima Seiki. The team included Ozgun Kilic Afsar, Sarah Nicita, Rosalie (Hsin-Ju) Lin, Liu Yang, Akshay Kothakonda, Zachary Gordon, and Cedric Honnet at MIT; and Megan Hofmann and Kristen Dorsey at Northeastern University.

During pregnancy, regular medical check-ups provide information about the health and development of the pregnant person and the child. However, these examinations only provide snapshots of their state, which can be dangerous, especially in high-risk cases. To enable convenient and continuous monitoring during this sensitive phase, an international research consortium is planning to further develop the technology of smart textiles. A patch equipped with highly sensitive electronics is meant to collect and evaluate vital data. In addition, the sensors will be integrated into baby clothing in order to improve the future of medical monitoring for newborns with the highest level of data security.

The beginning of a pregnancy is accompanied by a period of intensive health monitoring of the baby and the pregnant person. Conventional prenatal examinations with ultrasound devices, however, only capture snapshots of the respective condition and require frequent visits to doctors, especially in high-risk pregnancies. With the help of novel wearables and smart textiles, researchers in the EU-funded project Newlife aim to enable continuous obstetric monitoring in everyday life.

One goal of the consortium, consisting of 25 partners, is the development of a biocompatible, stretchable, and flexible patch to monitor the progress of the pregnancy and the embryo. Similar to a band-aid, the patch will be applied to the pregnant person’s skin, continuously recording vital data using miniaturized sensors (e.g., ultrasound) and transmitting it via Bluetooth.

For some time now, modern medical technology has been relying on smart textiles and intelligent wearables to offer patients convenient, continuous monitoring at home instead of stationary surveillance. At the Fraunhofer Institute for Reliability and Microelectronics IZM, a team led by Christine Kallmayer is bringing this technology to application-oriented implementation, benefitting from the Fraunhofer IZM’s years of experience with integrating technologies into flexible materials. For the integrated patch, the researchers are using thermoplastic polyurethane as base materials, in which electronics and sensors are embedded. This ensures that the wearing experience is similar to that of a regular band-aid instead of a rigid film.

To ensure that the obstetric monitoring is imperceptible and comfortable for both pregnant individuals and the unborn child, the project consortium plans to integrate innovative MEMS-based ultrasound sensors directly into the PU material. The miniaturized sensors are meant to record data through direct skin contact. Stretchable conductors made of TPU material tracks will then transmit the information to the electronic evaluation unit and finally to a wireless interface, allowing doctors and midwives to view all relevant data in an app. In addition to ultrasound, the researchers are planning to integrate additional sensors such as microphones, temperature sensors, and electrodes.

Even after birth, the new integration technology can be of great benefit to medical technology: With further demonstrators, the Newlife team plans to enable the monitoring of newborns. Sensors for continuous ECG, respiration monitoring, and infrared spectroscopy to observe brain activity will be integrated into the soft textile of a baby bodysuit and a cap. "Especially for premature infants and newborns with health risks, remote monitoring is a useful alternative to hospitalization and wired monitoring. For this purpose, we must guarantee an unprecedented level of comfort provided by the ultra-thin smart textiles: no electronics should be noticeable. Additionally, the entire module has to be extremely reliable, as the smart textiles should easily withstand washing cycles," explains Christine Kallmayer, project manager at Fraunhofer IZM.

For external monitoring of the baby's well-being, the project is also researching ways to use camera data and sensor technology in the baby's bed. Once the hardware basis of the patch, the textile electronics, and the sensor bed is built and tested, the project partners will take another step forward. Through cloud-based solutions, AI and machine learning will be used to simplify the implementation for medical staff and ensure the highest level of data security.

The Newlife project is coordinated by Philips Electronics Nederland B.V. and will run until the end of 2025. It is funded by the European Union under the Horizon Europe program as part of Key Digital Technologies Joint Undertaking under grant number 101095792 with a total of 18.7 million euros.

Scientists at the Fraunhofer Institute for Biomedical Engineering IBMT have been working with international partners to develop a technology platform to help relieve the symptoms of muscle tremors. Tiny biocompatible electrodes in the muscles, combined with external electrodes and controllers, form an intelligent network of sensors and actuators to detect muscle signals and provide electrical stimuli as needed. Together with exoskeletons, the technology could also help people with spinal cord injuries.

A compact controller on a belt or under a jacket, a couple of discreet textile electrodes on the arms and legs, and electrodes three centimeters long and barely a millimeter thin in the muscle are all it will take to help people with tremor disorders in the future. Whenever muscle tremors start, the system sends electrical stimuli to the muscles; these stimuli are registered by the nervous system. The nervous system then stops sending interfering signals to the muscles, which settle down again. That is the basic idea behind the technology that scientists from Fraunhofer IBMT have been working on together with project partners by developing, manufacturing, integrating and experimentally testing a set of intramuscular and external electrodes and associated controllers.

The scientists have already made some concrete achievements. “We have managed to reduce muscle tremors significantly in trials with patients,” explains Andreas Schneider-Ickert, project manager for active implants and innovation manager.

The system is part of the EU-funded joint project “EXTEND.” A total of nine project partners from five different countries are working together to develop a versatile platform of distributed neural interfaces. The technology will be able to help people with neuromuscular disorders, such as tremors, or symptoms of paralysis. Even people with spinal cord injuries could benefit from this. The technology uses external controllers to link the implanted electrodes into an intelligent network. The components communicate with each other wirelessly, exchange data, detect muscle signals and send targeted stimuli into the muscles. Implanted systems are already being used medically to provide stimulation, but the current methods require complex surgical operations that are considerably stressful for patients.

Implants for the human-machine interface
A key element of EXTEND is the implants, which are made from biocompatible platinum-iridium and silicone and are injected into the muscle through a catheter. Just three centimeters long and barely a millimeter in diameter, the tiny implant has an electrode at each end that functions as either a sensor or an actuator. External electrodes sewn into a textile ribbon supply the module with energy. This sends pulsed alternating current through the muscle tissue to the implant. “What’s innovative about this is not only the intelligent interplay between control electronics, sensors and actuators, but also the principle of modulating the alternating current to transmit data,” explains Schneider-Ickert.

Once it has been implanted and started, the sensors register the first signs of muscle tremors and pass the information on to the external components. The controller evaluates the data and sends signals through the textile electrodes to stimulate the muscle. This closes a control circuit of intelligently networked sensor and actuator components that counteracts the tremor.

The stimulus signal is not strong enough to trigger a muscle contraction directly. It is the nervous system that plays the decisive role here. This registers the stimulation in the muscle tissue and responds by stopping the commands that trigger the muscle tremor. At least that is the theory — the finer details of the relationship between tremors and signals from the nervous system are yet to be researched. “In clinical trials, however, our method is working astonishingly well. Initial trials have shown that providing the patient with stimuli for one or two hours is enough to reduce tremor symptoms for a longer period of time,” says Schneider-Ickert.

Since tremors often occur in both arms and both legs, implants can be injected and external textile electrodes placed in all the affected muscle groups. This creates a distributed sensor network. The controllers can keep track of all the implanted and external electrodes at the same time and control them in coordination with each other. All this happens in real time, with the person experiencing no delay at all.

The technology being developed in the EXTEND joint project is just as functional as conventional implant systems, but minimally invasive and therefore easier to accept and better for everyday use. The basic concept originates from a Spanish project partner. Based in this concept, the researchers at Fraunhofer IBMT designed the electrodes and implantable components and produced and integrated them in the in-house cleanroom. The scientists have 25 years of expertise in neuroprosthetics and active implants.

Exoskeletons to prevent paraplegia
For tremor patients, EXTEND brings them the hope that their symptoms can be alleviated considerably. However, the technology platform could also help people with spinal cord injuries thanks to motorized exoskeletons. This is a possible because, in cases of paralysis, the nerve fibers are often not completely cut off. They can still transmit stimuli from the brain, albeit very weakly. The sensors register the activity and transmit it to the controller, which analyzes all the signals, works out what movement the person wants to perform and activates exactly the right prostheses to support the muscles in executing the movement.

Following initial successful tests, the concepts and technologies used in EXTEND have been steadily developed, miniaturized, optimized and subjected to further implementation studies. As a result, the project has now been completed with a successful proof of concept of the miniaturized full system in humans. Fraunhofer IBMT will use the knowledge gained from EXTEND to further develop its expertise in the field of neuromuscular and neural interfaces.

Embroidering power-generating yarns onto fabric allowed researchers to embed a self-powered, numerical touch-pad and movement sensors into clothing. The technique offers a low-cost, scalable potential method for making wearable devices.

“Our technique uses embroidery, which is pretty simple – you can stitch our yarns directly on the fabric,” said the study’s lead author Rong Yin, assistant professor of textile engineering, chemistry and science at North Carolina State University. “During fabric production, you don’t need to consider anything about the wearable devices. You can integrate the power-generating yarns after the clothing item has been made.”

In the study published in Nano Energy, researchers tested multiple designs for power-generating yarns. To make them durable enough to withstand the tension and bending of the embroidery stitching process, they ultimately used five commercially available copper wires, which had a thin polyurethane coating, together. Then, they stitched them onto cotton fabric with another material called PTFE.

“This is a low-cost method for making wearable electronics using commercially available products,” Yin said. “The electrical properties of our prototypes were comparable to other designs that relied on the same power generation mechanism.”

The researchers relied on a method of generating electricity called the “triboelectric effect,” which involves harnessing electrons exchanged by two different materials, like static electricity. They found the PTFE fabric had the best performance in terms of voltage and current when in contact with the polyurethane-coated copper wires, as compared to other types of fabric that they tested, including cotton and silk. They also tested coating the embroidery samples in plasma to increase the effect.

“In our design, you have two layers – one is your conductive, polyurethane-coated copper wires, and the other is PTFE, and they have a gap between them,” Yin said. “When the two non-conductive materials come into contact with each other, one material will lose some electrons, and some will get some electrons. When you link them together, there will be a current.”
Researchers tested their yarns as motion sensors by embroidering them with the PTFE fabric on denim. They placed the embroidery patches on the palm, under the arm, at the elbow and at the knee to track electrical signals generated as a person moves. They also attached fabric with their embroidery on the insole of a shoe to test its use as a pedometer, finding their electrical signals varied depending on whether the person was walking, running or jumping.

Lastly, they tested their yarns in a textile-based numeric keypad on the arm, which they made by embroidering numbers on a piece of cotton fabric, and attaching them to a piece of PTFE fabric. Depending on the number that the person pushed on the keypad, they saw different electrical signals generated for each number.

“You can embroider our yarns onto clothes, and when you move, it generates an electrical signal, and those signals can be used as a sensor,” Yin said. “When we put the embroidery in a shoe, if you are running, it generates a higher voltage than if you were just walking. When we stitched numbers onto fabric, and press them, it generates a different voltage for each number. It could be used as an interface.”

Since textile products will inevitably be washed, they tested the durability of their embroidery design in a series of washing and rubbing tests. After hand washing and rinsing the embroidery with detergent, and drying it in an oven, they found no difference or a slight increase in voltage. For the prototype coated in plasma, they found weakened but still superior performance compared with the original sample. After an abrasion test, they found that there was no significant change in electrical output performance of their designs after 10,000 rubbing cycles.

In future work, they plan to integrate their sensors with other devices to add more functions.
“The next step is to integrate these sensors into a wearable system,” Yin said.

The study, “Flexible, durable and washable triboelectric yarn and embroidery for self-powered sensing and human-machine interaction,” was published online in Nano Energy. Co-authors included Yu Chen, Erdong Chen, Zihao Wang, Yali Ling, Rosie Fisher, Mengjiao Li, Jacob Hart, Weilei Mu, Wei Gao, Xiaoming Tao and Bao Yang. Funding was provided by North Carolina State University through the NC State Faculty Research & Professional Development Fund and the NC State Summer REU program.

 

Flexible electronics have enabled the design of sensors, actuators, microfluidics and electronics on flexible, conformal and/or stretchable sublayers for wearable, implantable or ingestible applications. However, these devices have very different mechanical and biological properties when compared to human tissue and thus cannot be integrated with the human body.

A team of researchers at Texas A&M University has developed a new class of biomaterial inks that mimic native characteristics of highly conductive human tissue, much like skin, which are essential for the ink to be used in 3D printing.

This biomaterial ink leverages a new class of 2D nanomaterials known as molybdenum disulfide (MoS2). The thin-layered structure of MoS2 contains defect centers to make it chemically active and, combined with modified gelatin to obtain a flexible hydrogel, comparable to the structure of Jell-O.

“The impact of this work is far-reaching in 3D printing,” said Dr. Akhilesh Gaharwar, associate professor in the Department of Biomedical Engineering and Presidential Impact Fellow. “This newly designed hydrogel ink is highly biocompatible and electrically conductive, paving the way for the next generation of wearable and implantable bioelectronics.”¹ 

The ink has shear-thinning properties that decrease in viscosity as force increases, so it is solid inside the tube but flows more like a liquid when squeezed, similar to ketchup or toothpaste. The team incorporated these electrically conductive nanomaterials within a modified gelatin to make a hydrogel ink with characteristics that are essential for designing ink conducive to 3D printing.

“These 3D-printed devices are extremely elastomeric and can be compressed, bent or twisted without breaking,” said Kaivalya Deo, graduate student in the biomedical engineering department and lead author of the paper. “In addition, these devices are electronically active, enabling them to monitor dynamic human motion and paving the way for continuous motion monitoring.”

In order to 3D print the ink, researchers in the Gaharwar Laboratory designed a cost-effective, open-source, multi-head 3D bioprinter that is fully functional and customizable, running on open-source tools and freeware. This also allows any researcher to build 3D bioprinters tailored to fit their own research needs.

The electrically conductive 3D-printed hydrogel ink can create complex 3D circuits and is not limited to planar designs, allowing researchers to make customizable bioelectronics tailored to patient-specific requirements.

In utilizing these 3D printers, Deo was able to print electrically active and stretchable electronic devices. These devices demonstrate extraordinary strain-sensing capabilities and can be used for engineering customizable monitoring systems. This also opens up new possibilities for designing stretchable sensors with integrated microelectronic components.

One of the potential applications of the new ink is in 3D printing electronic tattoos for patients with Parkinson’s disease. Researchers envision that this printed e-tattoo can monitor a patient’s movement, including tremors.

This project is in collaboration with Dr. Anthony Guiseppi-Elie, vice president of academic affairs and workforce development at Tri-County Technical College in South Carolina, and Dr. Limei Tian, assistant professor of biomedical engineering at Texas A&M.
This study was funded by the National Institute of Biomedical Imaging and Bioengineering, the National Institute of Neurological Disorders and Stroke and the Texas A&M University President’s Excellence Fund. A provisional patent on this technology has been filed in association with the Texas A&M Engineering Experiment Station.

¹ This study was published in ACS Nano.

Giant arsenals of unexploded ordinance are sitting on the ocean floor, lost in battle or dumped as waste. The risky job of detecting these underwater hazards is currently given to submarines specially fitted for the purpose. But even they cannot get to some of the tighter or harder to reach spots, forcing expert divers to go down and take over the often life-threatening work.

A German research consortium including Fraunhofer IZM is now using a submarine robot that is as nimble and mobile as a manta ray and equipped with innovative connected sensors on its fins to gather more information about its surroundings. It can measure water pressure so precisely that metal objects can be detected on the ocean floor, even if they are covered by sediment.

Unmanned underwater vehicles or UUVs have been in use for several years, but high-tech pioneers for reliable underwater communication and innovative bionics like EvoLogics GmbH have let themselves be inspired by marine life like manta rays and adapted their look and technical anatomy to the submarine world.

With the enormous “wingspan” of their fins, manta rays are known to cover vast distances, while their extremely flexible vertebrae means that they can make surprisingly sharp turns on their seemingly weightless journey through the sea. Their robotic cousins can be very agile as well, but they were not smart enough yet to replace the professional divers who had to scour the sea floor for hours, looking for lost ordinance from the First or Second World War or other hazardous metal waste before offshore wind farms could be built or intercontinental cables could be put down. Now, the new robo ray will make it possible to detect submarine hazards with a whole battery of sensors.

The “Bionic RoboSkin” project, supported by Germany’s Ministry of Education and Research, is working to give the manta-shaped UUVs a flexible bionic sensor skin to help them navigate their underwater world. The skin is made from a compound fabric that is fitted with sensor elements and water-resistant connectors to supply the sensors with power and transmit their data. Researchers from Fraunhofer IZM have taken on the challenge of developing these integrated sensor modules with which the UUVs can detect touch or the proximity of objects and virtually see and analyze their surroundings. The project consortium is headed by EvoLogics GmbH and includes other experts in the field from TITV Greiz, Sensorik Bayern GmbH, the diving specialists of BALTIC Taucherei- und Bergungsbetrieb Rostock GmbH, and GEO-DV GmbH, all with one mission: To create a new generation of robots that can support their human partners with a range of semi or fully automated services and functions.

Their capabilities will not be limited to the sea: The researchers are looking at a second use case for a land-based robot sensor platform, fittingly called “Badger” or “Dachs” in German. It will navigate by GPS and be fitted with ground penetrating radar to detect metal objects below ground or conduct other ground survey work in harder to reach places (including tunneling work).

Under the robotic manta ray’s deceptively lifelike shell lies intricate technology: A permeable and therefore pressure-neutral fabric skin is created and fitted with integrated microelectronics for touch, flow, motion, and position sensors. This textile skin is then pulled tight over the robotic fins, creating a soft robotics machine that can sense its surroundings. The team at Fraunhofer IZM is responsible for the electronics that make this possible: They developed sensor nodes suitable for submersible use that can collect and pre-process the sensor data. These nodes do not only have to be fit for purpose, they also need to be extremely miniaturized to fit underneath the thin fabric skin and integrate the necessary connectors. In active operations below the waterline, these sensors can track parameters like acceleration, pressure, or absorbency. The researchers also included LEDs in the circuit board design that let the robotic manta rays communicate with human divers, for instance to signal a turn.

All of these components and sensor packages are integrated by means of a highly miniaturized embedding method and protected from the cold and wet environment by a robust case. Despite this, the footprint of the embedded modules is amazingly small at 23 x 10.5 x 1.6 mm³, fitting a complete sensor package and microcontroller in something the size of a common door key. The case itself works as a conductor by creating the mechanical and electrical contact with the sensor skin itself. The researchers chose a modular two-part design from their original vision of the product: The embedding module combines the individual electronic components on a millimeter scale for exceptional integration; the module case acts as the mechanical interface with the skin and makes the system as robust as it has to be for its destined purpose. The coupling between module and case relies on a seemingly simple clipping action: Small pins on the connector surface on the skin and tiny hooks on the sensor module itself snap together to form an easily de- and attachable interface. The resulting system is modular to allow easy reconfiguration.

The researchers at Fraunhofer IZM will now subject their robotic manta ray to a series of tests with their project partners. The results and findings from the “Bionic RoboSkin” project will likely be of use for many other projects and contribute to more pressure-neutral and reliable packaging solutions for flexible, mobile, and smarter service robots.

The “Bionic RoboSkin” project is supported through the VDI/VDE-IT by the Ministry of Education and Research (funding code 16ES0914) as part of the federal government’s research and innovation campaign 2016 to 2020 “Microelectronics from Germany – Driver of Innovation for the Digital Economy”.

Most people want to live as independently as possible in old age. Exhibitors at the industry's leading trade fair ALTENPFLEGE from April 26 to 28 in Essen, Germany will be showing how senior facilities with modern interior design and smart equipment meet this need.

Demand for forms of housing such as service living is on the rise. Studies predict a need for around 540,000 new service living units in the coming years. One of the major trends at this year's 32nd edition of the Altenpflege trade fair is how senior facilities are meeting the rapidly growing demand with flexible room design and digital support. They can be seen in the Aveneo special show, including intelligent systems for stove shut-off, lighting control and room temperature, as well as for fall sensors and emergency calls.

Future tenants or buyers of serviced apartments are prepared to invest specifically in their own living environment (source: Terragon study 2021). The focus is on a feel-good atmosphere, a high level of security and the option of using care services if required. "This can be facilitated by a cleverly thought-out arrangement of the rooms within a serviced apartment, for example by arranging the bathroom and bedroom right next to each other and making the wall with the washbasin rotatable," explains Carolin Pauly, managing director of Universal Rooms, which considers itself to be the interface between the wishes of the operators and the products in the serviced apartment market. "The furniture and furnishings industry is called upon to design modern collections with hidden product features that make life easier in old age," Pauly demands. This could be, for example, a grab handle built into the washbasin or a dining table that can be accessed by a wheelchair.

Lighting management also plays an important role. It should convey a sense of well-being and security as well as provide orientation and safety. Age-related clinical pictures in particular place high demands on lighting. Here, lighting systems that simulate the natural day and night rhythm can provide help.

Living, care and digitalization combined
The Chief Executive Officer of the Evangelische Heimstiftung (EHS - Evangelical Home Foundation), Bernhard Schneider, sees "an individually and comfortably furnished apartment that uses intelligent technology to provide a great deal of security and self-determination" as the senior living of the future. "I am certain: In the future, in a sector-free setting, we will have to understand housing, nursing and care, and digitalization even more strongly as building blocks that can be combined as needed."

According to Schneider, this starts with housing: In a nursing apartment or an assisted living apartment, in a shared apartment or other form of communal living, in a residence or an intergenerational project. All forms of housing should be well integrated into the neighborhood - this requires reliable, financed advisory structures, for example through neighborhood managers. In addition, there is care, support and assistance, in the form of day or night care, a mobile service or volunteers. "And technology, for example through our Aladien system, i.e. with intelligent home emergency call, fall sensors, stove shut-off, roller shutters and light control, video door telephony, etc. In the future, Aladien will evolve into a service robot," predicts Schneider.

This makes it possible for people to live a self-determined life and participate in society, even in old age. That's what people want, he says: a pleasant living environment, social contacts, cultural offerings and the certainty that someone will take care of them if necessary. "What we need for this is political commitment in the form of an ambitious funding program for modern forms of housing in old age," demands the EHS CEO. This would not only help the older generation, but young families could also benefit because this would free up the far too spacious apartments and terraced houses of the older generation for them.

ALTENPFLEGE – Trade fair and congress for the care industry since 1990
The traditional leading trade show for the care industry has so far been held alternately in Hanover and Nuremberg. From this year it alternates between Essen and Nuremberg. It covers all segments of professional geriatric care: services and products for care and therapy, occupation and education, IT and management, nutrition and home economics, textiles and hygiene as well as space and technology. In more than 30 lecture blocks, the accompanying trade congress covers the current topics of the industry, such as digitalization, the future of professional nursing care, hospice and palliative care, training or the new collectively agreed payment under the Healthcare Development Act (Gesundheitsversorgungsweiterentwicklungsgesetz - GVWG).

Alzheimer's and other dementias are among the most widespread diseases today. Diagnosis is complex and can often only be established with certainty late in the course of the disease. A team of Empa researchers, together with clinical partners, is now developing a new diagnostic tool that can detect the first signs of neurodegenerative changes using a sensor belt.

Forgetfulness and confusion can be signs of a currently incurable ailment: Alzheimer's disease. It is the most common form of dementia that currently affect around 50 million people worldwide. It mainly afflicts older people. The fact that this number will increase sharply in the future is therefore also related to the general increase in life expectancy.

If dementia is suspected, neuropsychological examinations, laboratory tests and demanding procedures in the hospital are required. However, the first neurodegenerative changes in the brain occur decades before a reduced cognitive ability becomes apparent. Currently, these can only be detected by expensive or invasive procedures. These methods are thus not suitable for extensive early screenings on a larger scale. Empa researchers are working with partners from the Cantonal Hospital and the Geriatric Clinic in St. Gallen on a non-invasive diagnostic method that detects the early processes of dementia.

Signs in the unconscious
For the new method, the researchers Patrick Eggenberger and Simon Annaheim from Empa's Biomimetic Membranes and Textiles lab in St. Gallen relied on a sensor belt that has already been used successfully for ECG measurements and has now been equipped with sensors for other relevant parameters such as body temperature and gait pattern. This is because long before memory starts to deteriorate in dementia, subtle changes appear in the brain, which are expressed through unconscious bodily reactions.

These changes can only be recorded precisely when measurements are taken over a longer period of time, though. "It should be possible to integrate the long-term measurements into everyday life," explains Simon Annaheim. Skin-friendly and comfortable monitoring systems are essential for measurements that are suitable for everyday use. The diagnostic belt is therefore based on flexible sensors with electrically conductive or light-conducting fibers as well as sensors for motion and temperature measurement.

To enable such long-term measurements to be used for monitoring neurocognitive health, the researchers are integrating the collected data into in-house developed mathematical models. The goal: an early warning system that can estimate the progression of cognitive impairment. Another advantage is that the data measurements can be integrated into telemonitoring solutions and can thus improve patient care in their familiar environment.

Suspicious monotony
The human body is able to keep its temperature constant in a range of 1 degree Celsius. The values naturally oscillate in the course of the day. This daily rhythm changes with age and is conspicuous in neurodegenerative diseases such as dementia or Parkinson's disease. In Alzheimer's patients, for example, the core body temperature is elevated by up to 0.2 degrees Celsius. At the same time, the spikes in daily temperature fluctuations are dampened.

In a study, the researchers have now been able to show that altered skin temperature readings measured with the sensor belt actually provide an indication of the cognitive performance of test subjects – and can do so well before dementia develops. The test subjects in the study included healthy people with or without mild brain impairment. This mild cognitive impairment (MCI) does not represent a disability in everyday life, but it is considered a possible precursor to Alzheimer's disease. The subjects took part in long-term measurements and neuropsychological tests. It was found that a lower body temperature, which fluctuated more throughout the day, was linked to a better cognitive performance. In individuals with MCI, body temperature varied less and was slightly elevated overall.

The heartbeat is also subject to natural variations that show how our nervous system adapts to sudden challenges. The small silence between two heartbeats, about one second in duration, has great significance for our health: If this pause always remains the same, our nervous system is not at its best.

A study by researchers from ETH Zurich determined that poorer measurements in older, healthy people can be improved within six months through cognitive-motor dance training. In these "exergames," the test subjects imitated sequences of steps from a video. In contrast, participants who instead only trained in straight lines on a treadmill, but also trained their memory, benefited less.

"The point is to intervene early with appropriate training as soon as the first negative signs can be measured," says Patrick Eggenberger. "With our sensor system, any improvements in cognitive performance can be tracked through movement-based forms of therapy." Studies with long-term monitoring will now be used to clarify how the sensor measurements can be used to predict the progression of mild brain disorders.

Further information
Dr. Simon Annaheim
Biomimetic Membranes and Textiles   
Phone +41 58 765 77 68
Simon.Annaheim@empa.ch