Tag Archives: ETTLIN Spinnerei und Weberei Produktions GmbH

Anti-theft with smart fabrics

When you cut or tear the new smart fabric developed at the Fraunhofer Institute, an alarm is triggered. Here’s a little more about the fabric from the Sept. 6, 2012 news item on physorg.com,

Thieves are unlikely to appreciate this fabric, which looks innocuous but in fact incorporates a fine web of conductive threads connected to a microcontroller that detects warning signals emitted when the fabric is cut and triggers an alarm. This system can be used to protect buildings, bank vaults, and trucks against even the most wily of intruders. Vehicles parked overnight at truck stops are particularly vulnerable to attacks by thieves who slit open the canvas tarp covering the trailer while the driver is asleep and make off with the cargo. If the tarp were made from the smart fabric, the driver in the bunk would be immediately alerted.

The smart fabric was developed by researchers at the Fraunhofer Institute for Reliability and Microintegration IZM in Berlin in collaboration with the Technische Universität Berlin and ETTLIN Spinnerei und Weberei Produktions GmbH. The company in Ettlingen [Germany] manufactures technical textiles, among other things, and has filed a patent for the innovative fabric.

The Sept.5, 2012 Fraunhofer Institute press release (which originated the news item) provides detail about the technology and its advantages,

What makes this solution unique is the fact that it not only signals the presence of intruders but also indicates the precise point of forced entry. The fine lattice of conductive threads woven into the fabric enables the place where it was cut to be identified to the nearest centimeter. Other solutions currently on the market require a complex system of optical fibers, which naturally makes them more expensive.

There are also other reasons why this fabric is cheap to produce. The process makes exclusive use of standard materials and components such as silver-coated conductive threads and a simple but robust signal evaluation system. A further advantage is that “the conductive thread can be incorporated in the polyester substrate using an industry-standard textile-weaving process,” explains Simon [IZM project manager Erik Simon]. The result is reams of fabric that can be trimmed to any length and customized to provide the desired functionality for surfaces of any size, from one square meter upward.

The conductive lattice and the data-processing module that triggers the alarm in the monitoring center are incorporated in a low-temperature process using joining techniques borrowed from the semiconductor industry such as adhesive pressure bonding and non-destructive welding. “This method has never been used before in this kind of application,” says Simon, who describes the process as “simple and reliable”. And this is precisely the selling point of the solution: the ability to create an entirely new product with immediately appreciable benefits using existing materials and joining techniques.

Part of what makes this an ‘exciting’ development is the fabric’s durability (from the Fraunhofer Institute press release),

The all-important question was to determine the fabric’s reliability and durability, especially with respect to the electrical contacts. To verify this, the textile alarm system was put through a grueling series of tests in the IZM laboratories. It was beaten and tumbled in a washing machine at 40 degrees Celsius, and exposed to the elements for 1,000 hours at a relative humidity of 85 percent and a temperature of 85 degrees Celsius. It was then placed in a furnace in which it was subjected to 1,000 temperature cycles ranging from minus 40 to plus 85 degrees Celsius. The smart textile stood up to this torture without flinching. Simon: “It didn’t fail once.”

Of course, at some point, technically astute and determined thieves will find a way to hack the fabric alarm but in the meantime, some of us can rest more easily.