Thread who feels how and when you move? New technology makes it possible

Engineers at Tufts University have created and tested flexible fiber-based sensors that will be able to measure neck movement, providing data on direction, angle of rotation and rate of head movement. The discovery raises the possibility for thin, fuzzy tattoo-like pieces that could, according to Tufts’ team, measure athletic performance, monitor employee or driver fat, help with healing develop physical, virtual reality games and systems, and advance computer-generated images in cinematography. The technology, described today in Scientific Reports, contributing to a growing number of fiber – based sensors developed by Tufts engineers that can be woven into fabric, measuring gases and chemicals in the environment or metabolites in sweat.

In their experiments, the researchers placed two threads in an “X” pattern on the back of a subject’s neck. Covered with carbon-based ink, the sensors detect movement as the fibers bend, creating a snort that changes the way they conduct electricity. When the subject made a series of head movements, the wires sent signals to a small Bluetooth module, which then sent wireless data to a computer or smartphone for analysis.

The data analysis included solemn machine learning techniques to interpret the signals and translate them to measure head movements in real time, with 93% accuracy. In this way, the sensors and processor monitor movement without interference from wires, bulky devices, or restrict conditions such as the use of cameras, or restriction to a room or lab space.

Although algorithms need to be specialized for each location on the body, principle validation shows that fiber sensors could be used to measure movement in other organs, according to the researchers. The appropriate pieces of skin or even clothing in a form containing the fibers can be used to monitor movement in situations where the measurements are most appropriate, such as in the field, workplace or classroom. school. The fact that no camera is required provides for additional privacy.

“This is a promising testament to how we can create sensors that monitor our health, performance, and the environment in an unobtrusive way,” said Yiwen Jiang, an undergraduate student at the University’s School of Engineering. Tufts and the first author of the study: “More work needs to be done to improve the breadth and accuracy of the sensors, which in this case may involve collecting data from a larger range of sensors. threads are constantly rotated or arranged in a pattern, and develop algorithms that improve the measurement of arctic motion. “

Other types of accessible motion sensor designs have included 3-axis gyroscopes, accelerometers and magnetometers to detect the subject’s motion relative to their surroundings. These sensors are based on inertial measurements – measuring how the body accelerates, rotates, or moves up and down – and tend to be larger and more inconvenient. For example, with other systems, to measure head movement, one sensor must be placed on the face and another on the neck above the vertebrae. Improper equipment placement can impede the free movement of subjects or just convenience without realizing it will be measured.

For situations like on the athletic field, the novel thread-based sensor paradigm could be a game changer. By placing tattoo-thin pieces on different joints, an athlete was able to carry motion sensors to detect their physical movement and shape, while fiber-based sweat sensors could, described in earlier work by the Tufts team, monitoring their electrolytes, lactate and other biological indicators of performance in sweat.

Along the way, a threaded sensor patch could warn of truck driver obesity or other situations where it is essential to monitor operator awareness, monitoring the movements of someone who is about to go off.

“If we can advance this technology, there could be a wide range of applications in healthcare as well,” Jiang said. “For example, those studying Parkinson’s disease and other neuromuscular diseases could monitor subjects’ movements in their normal circumstances and daily life to collect data about their condition and the effectiveness of treatments.”

“The goal in creating fiber-based sensors is to make them ‘disappear’ from the wearer,” said Sameer Sonkusale, professor of electrical and computer engineering at Tufts School of Engineering, director Tufts Nanolab, and the corresponding author of the study. ”The creation of a coated fiber capable of measuring movement is an amazing achievement, made even more remarkable by the fact that Yiwen developed this invention as an undergraduate. We look forward to updating the technology and exploring its many capabilities. ”

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