From the Sector

Smart textiles have the potential to revolutionise healthcare. In his doctoral thesis in textile technology at the University of Borås, Emanuel Gunnarsson presents unique solutions to the bottleneck that has long inhibited the market.

With an ageing population, increasing demands are being placed on healthcare and smart textiles can offer a solution where only imagination sets limits. “The long-term goal of most smart textiles is for them to be so easy to use that the user doesn't think of them as anything more than regular garments. No special procedure should be needed to use them. If we succeed in that, we won't burden healthcare by having healthcare personnel administer vital parameter monitoring such as blood pressure and pulse, as the user can handle it themselves,” said Emanuel Gunnarsson.

In his work, he has investigated how a t-shirt for measuring heart rhythm and movement patterns, and garments for electrostimulation, can be produced in a single step. This involves the connection between the contact surfaces (electrodes), the insulated conductive paths between the electrode and the contact point, and the electrical measuring equipment required.

“This, as far as we know, has never been described before. We are completely convinced that this is the solution to a significant bottleneck when it comes to getting the smart textile market going in earnest,” said Emanuel Gunnarsson.

His work has resulted in two different simple ways to produce smart textiles. He demonstrates that sensors can be integrated using standard textile manufacturing methods. The research also includes criticism of some of the methods used to measure the functionality of smart textiles, and advice on how to do it better instead.

“The next natural step will be to see how these garments cope with one of the toughest challenges a garment faces, namely washing. Especially as these garments must be worn closest to the skin, they will need to be washed relatively often,” said Emanuel Gunnarsson.

Studies from other universities indicate that the yarns used to measure signals from the body do not withstand many washes, but after a small pilot study, Emanuel Gunnarsson is hopeful of the opposite.

It looks like a normal shirt, but it has it all: The new SmartTex shirt uses integrated sensors to transfer physiological data from astronauts to Earth via a wireless communication network. In this way, the effects of the space environment on the human cardiovascular system will be evaluated and documented, especially with regard to long-term manned space missions. Developed by the German Aerospace Center (DLR) in cooperation with DSI Aerospace Technology, the Medical Faculty of Bielefeld University and textile research partner Hohenstein, SmartTex will be tested for the first time as part of the Wireless Compose-2 (WICO2) project by German ESA astronaut Dr. Matthias Maurer, who will leave for his ‘Cosmic Kiss’ mission on the International Space Station (ISS) for six months on October 30, 2021.

"We were already able to gain valuable insights into the interaction of the body, clothing and climate under microgravity conditions during the previous projects Spacetex (2014) and Spacetex2 (2018)," explains Hohenstein Senior Scientific Expert Dr. Jan Beringer. The insights provided at the time by the mission of ESA astronaut Dr. Alexander Gerst have now been directly incorporated into the development of the new SmartTex shirt at Hohenstein. "Matthias Maurer can wear his tailor-made shirt comfortably on his body during his everyday work on the International Space Station. For this, we used his body measurements as the basis for our cut development and the production of the shirt. We integrated the necessary sensors as well as data processing and communication modules into the shirt's cut in such a way that they interfere as little as possible and are always positioned in the right place, regardless of the wearing situation. This is the prerequisite for reliably measuring the relevant physiological data." The SmartTex shirt is intended to provide a continuous picture of the vital functions of astronauts. This will be particularly relevant for future long-term manned space missions to the Moon and Mars.

For example, during the BEAT experiment (Ballistocardiography for Extraterrestrial Applications and long-Term missions), Matthias Maurer will be the first astronaut to wear a T-shirt equipped with sensors that measure his ballistocardiographic data such as pulse and relative blood pressure. For this purpose, the sensors were calibrated in the :envihab research facility at the DLR Institute of Aerospace Medicine in Cologne. Details on the contraction rate and opening and closing times of the heart valves, which are normally only accessible via sonography or computer tomography, can also be read from the data material. The goal is to study the effects of the space environment on the human cardiovascular system. To be able to analyse these effects realistically, Matthias Maurer's ballistocardiographic data will be recorded before, during and after his stay on the ISS. For the future, a technology transfer of the SmartTex shirt for application in the field of fitness or even in telemedicine is conceivable.

Wireless Compose-2 (WICO2)
The project was planned and prepared by the German Aerospace Center (DLR) and its cooperation partners DSI Aerospace Technology, Hohenstein and the University of Bielefeld. The wireless communication network reads sensor data and can determine the position of people and objects in space by propagation times of radio pulses. It is also available as a platform for several experiments on the ISS. The determined data is temporarily stored within the network and read out at regular intervals by the astronauts. These data packets are then transferred to Earth via the ISS link and analysed by the research teams. It can generate its own energy from artificial light sources via solar cells.

ESA astronaut Dr. Matthias Maurer in summer 2021 during preliminary talks on the Cosmic Kiss mission in DLR's :envihab in Cologne. © DLR

Sensors measure physiological data during a test run on Earth. © DLR

With the "SmartTex" shirt, astronauts can wear the necessary sensors comfortably on their bodies. © DLR

Dr. Jan Beringer, Hohenstein Senior Scientific Expert. © Hohenstein