Footfalls and Hearbeats

If you’ve ever had an injury where you needed to have a leg or an arm wrapped with an elastic compression bandage, you have probably experienced firsthand the biggest problem with this treatment. “Is that too tight? Is it too loose?” The person applying the wrap has to guess about the correct tension; too much and you can restrict blood flow, but too loose and the bandage does no good and is prone to slipping off. This problem is much bigger with patients who have skin ulcers as a result of diabetes or other diseases. In many cases, the patient is not able to provide much feedback about the pressure, and so the healthcare worker has to guess.

A New Zealand company called Footfalls & Hearbeats hopes to eliminate this problem. Their researchers have developed a proprietary conductive yarn that can be woven into knitted fabrics to create a flexible, stretchable material suitable for use in everything from clothing to compression bandages. One big difference between their material and other conductive fabrics is that the yarn is also sensitive to pressure. Its resistance changes in predictable ways in response to pressure (as you can see demonstrated in the video above). Rather than have to figure out how to embed sensors and then connect them to some controller to collect the readings, in this case the fabric is the sensor which greatly simplifies the application. This could lead to wraps that report the precise amount of pressure being applied to the patient’s body, eliminating guesswork and possible complications.

The company hopes to license its technology to partners who would produce the product. The compression bandage market alone is $2 billion worldwide, and the technology has a wide range of other potential applications from medical uses to sports. Earlier this spring, the company signed an agreement with the German medical company Medi to use the fabric technology in their medical compression therapy products.