Embedded sensors turn wearables into washables

September 20, 2000

Embedded sensors turn wearables into washablesSmart fabric improves patient monitoringDid you ever think you'd see Star Trek technology in real-world use? Advances in processing capability and wireless networking are taking mobile

Embedded sensors turn wearables into washables

Smart fabric improves patient monitoring

Did you ever think you'd see Star Trek technology in real-world use? Advances in processing capability and wireless networking are taking mobile computing to new heights—the applications are limited only by developers' and designers' imaginations. In healthcare, these advances are moving traditionally hospital- and facility-bound procedures out into everyday use and allowing patients to get on with the business of living.

Two companies, Sensatex/Lifelink and Lifeshirt.com, have found unique ways to integrate wearable computers with wireless patient monitoring products—and create a fashion statement in the process (HNN 9/6/00). The theory is that many chronically ill and recovering patients need monitoring on a more consistent basis, especially those in an ambulatory care or home environment and not directly under a physician's care 24 hours a day. While mobile vital-signs monitoring devices are not new, comfortable and unobtrusive lightweight, form-fitting monitors offer some obvious advantages. Thus, intelligent clothing is born.

Sensatex/Lifelink of Dallas is taking the OEM route with its wearable technology. The firm is developing a wireless platform designed to facilitate moving information from the wearer's body to any point on a network. Sensatex/Lifelink licensed the technology from the Georgia Institute of Technology, which received original funding for the project from DARPA, a division of the U.S. Department of Defense.

The company's first product to incorporate this technology is the Smart Shirt. It is made from a textile, developed by the Georgia Tech School of Textile and Fiber Engineering, that uses conductive fibers to enable data collection from the wearer's body to an outside network or wireless device and data transmission from networks or devices to the wearer's body. The company plans to put existing FDA-approved sensors on the shirt to further facilitate data collection.

"The shirt is just a naked motherboard," said Jeff Wolf, CEO of Sensatex/Lifelink and founder of Seed One Ventures, the venture capital firm that funded Sensatex. "There is a proprietary network of fibers inside the garment, and with plug-and-play technology you can plug anything into it."

Sensatex is also developing an applications programming interface (API) intended as an open standard to facilitate the development of other applications using the Smart Shirt platform. According to Wolf, the API will support standards-based wireless networking protocols such as Bluetooth and IEEE 802.11 and will allow for easy adaptation of existing applications.

"There are really no practical limits to the capacity of the shirt," he said. "We can run live video and live audio through it. It's only constrained by the bandwidth capacities of the networks used."

The Smart Shirt and the API are in beta testing and should be commercially available in 12 to 18 months. Sensatex is in talks with several potential partners to develop the monitoring applications, according to Wolf. Although prices for the products have not yet been set, the company's goal is to price the Smart Shirt products in line with competing monitors. The deciding cost factor will be application, he said.

"There are monitors out there from a couple of hundred dollars to tens of thousands of dollars," he said. "We want to make (our technology) less expensive and more affordable than the competition."

While Sensatex/Lifelink is focused on providing the infrastructure behind portable monitoring, LifeShirt.com is focusing on the application itself by defining the universe of vital signs that its product, the LifeShirt, can track. The system consists of a tanktop-style shirt with embedded sensors, a personal digital assistant (PDA) module, and related monitoring software called RespiEvents that received FDA 510(k) clearance at the end of August. The software was developed by Non-Invasive Monitoring Systems, LifeShirt.com's research and development partner. NIMS also owns stock in the Ojai, CA-based company.

"The RespiEvents software takes raw data and turns it into waveforms so that a researcher or physician can read it," said Andrew Behar, COO of LifeShirt.com. "The FDA approved the ambulatory use of the software, which was previously approved for in-hospital use only. We have added software coding to filter out extraneous information so that we get clean data."

The shirt's embedded sensors gather data continuously on more than 40 vital signs, and this information is loaded into the PDA module connected to the LifeShirt. The PDA module encrypts the data and provides the conduit to send the information to the LifeShirt.com data center for processing and analysis. The data are sent via modem or by hotsyncing—that is, setting the PDA into the cradle connected to a PC and using the hotsync function to replicate data from the module to the PC or the Internet. Clinicians can choose how they wish to receive the patient information, from faxes to Web-based viewing.

"The Internet is a useful data transport mechanism but not a necessary one," he said. "We will be able to go over regular phone lines and are looking at all the different transport options right now."

The current system is a prototype in alpha testing, but LifeShirt expects to begin conducting beta tests on the hardware in the next few weeks. A commercial version should be available in the first quarter of 2001 at a cost of $100 for the shirt, $150 for the Palm OS-based PDA module, and $30 a day for the monitoring service. The firm anticipates the first market for its system will be in clinical drug trials and plans to conduct pilot studies with pharmaceutical companies with which it already has relationships.

LifeShirt also sees potential partnerships with some of its competitors, including Cyber-Care and Kodak. Because of the depth and breadth of the vital-signs information that it tracks and the mobile nature of the LifeShirt, the company sees it as the point-of-care data-gathering device that can complement home-based systems developed by these and other firms, Behar said. LifeShirt has also been approached by some nonhealthcare entities, including professional sports teams, regarding other development opportunities.