Smart Fabric Can Sense Motion to Help Physical Therapy Patients to Optimize Recovery

Researchers at Dartmouth College have developed a low-cost motion-sensing fabric that physical therapy patients can wear on their arm. The fabric can provide patients with feedback about the most appropriate arm angles to take in order to help accelerate recovery. It also allows clinicians to test an injured patient’s recovery and the effectiveness of physical therapies.

Monitoring the movement of an injured joint can help patients to improve healing and avoid further injury. It can also tell clinicians if physical therapy treatments are working. Existing technology to monitor joint movement can be bulky, rigid, and expensive, and sometimes suffers from poor sensitivity.

With the aim to develop a better solution, a group of Dartmouth researchers created an inexpensive motion-sensing smart fabric that is portable, comfortable, and sensitive. “We wear fabrics all the time, so they provide the perfect medium for continuous sensing,” said Xia Zhou, a researcher involved in the study. “This study demonstrates the high level of performance and precision that can be acquired through basic, off-the-shelf fabrics.”

The researchers focused on washable and inexpensive fabrics as the base material for the wearable monitor, with a cost of $50 per monitor. “For less than the price of some sweatshirts, doctors and coaches can have access to a smart-fabric sensing system that could help them improve athletic performance or quality of life,” said Qijia Shao, another researcher involved in the study.

The fabric contains a thin silver layer for electrical conductivity, and the monitor includes a micro-controller that receives and processes the data generated. As the fabric stretches during joint movement, it generates data on skin deformation and pressure, and the micro-controller interprets these data to calculate the joint rotational angle.

So far, the researchers have tested the device on the elbow joint in ten volunteers, who reported that it was comfortable, easy to use, and flexible. The monitor demonstrated sensitive measurements of joint motion and a very low error rate.

“Testers even saw this for use in activities with high ranges of movement, like yoga or gymnastics,” said Zhou. “All participants said they’d be willing to purchase such a system for the relatively inexpensive price tag.”