Researchers at the Singapore University of Technology and Design have created a flexible knee wearable that contains integrated circuitry within its knitted structure. The wearable can track joint movement in real time, assisting clinicians in spotting the early signs of movement disorders or allowing them to track the progress of patients undergoing physical therapy to improve their movement.
The new device was designed to be as comfortable as possible, and functions as a single knitted garment, with sensors and other functional components such as resistors forming flexible circuits within the fabric.
Wearables are well suited for monitoring our ability to move. This is particularly important for patients with mobility disorders. Such patients can experience functional decline, and may struggle to keep their balance, and experience symptoms such as muscle weakness, unsteady gait, and joint pain. Spotting these signs early and then keeping track of a patient’s progress is important, but many patients may not be fully aware of the extent of the problem until it has progressed to a more advanced stage.
Some previous iterations of wearables to track movement have been bulky and uncomfortable to wear. It can be difficult to integrate electrical components into an unobtrusive and comfortable device. To achieve this, these researchers have used conductive fabrics to integrate electrical systems into a knitted fabric wearable that can track movements of the knee joint.
The goal with the technology was to ensure that the sensors were as accurate as possible and that they did not rely on many external components (which has been a limitation with other wearables made using conductive fabrics), but rather were largely fully integrated into the knitted fabric. They combined highly elastic dielectric yarn with electrically conductive yarn in various stitching patterns to achieve an integrated fabric wearable that is comfortable to wear for long periods, but which can provide accurate readings.
So far, the researchers have tested the wearable with human volunteers. They have found that it can detect a range of movements, and the integrated sensors can recognize a step within 90 milliseconds and can indicate a 0.12 degree change in joint angle, suggesting that the technology is suitable for monitoring human movements in real time.
Here’s a video from Singapore University of Technology and Design about the technology:
Study in journal Advanced Healthcare Materials: All Knitted and Integrated Soft Wearable of High Stretchability and Sensitivity for Continuous Monitoring of Human Joint Motion