RFID Motion Sensor for Security

By Andrew Price

Axcess has unveiled a new RFID tag that can detect the unauthorized movement of anything from PCs to missiles.


July 18, 2002 ? Companies have always suffered losses from theft. Since Sept. 11, however, businesspeople worry not just about the loss of a laptop or a case of detergent. The fear is that radio-active material from a hospital could be used to make a dirty bomb, or that a dangerous chemical or biological agent could be stolen and used against innocent people.

To address the problem, Axcess Inc. (Nasdaq: AXSI), a Dallas-based provider of security and asset management products, has unveiled a new radio frequency identification tag that can automatically detect the unauthorized movement of assets, from PCs to missiles, and can transmit an alarm.

The tamper-proof RFID tag uses a tiny ball and cylinder mechanism that is built right onto the tag’s printed circuit board. When the tag is moved, the ball rolls and makes a connection. That triggers the battery-powered RFID tag to broadcast a UHF signal to a reader, which can be up to 100 feet away.

The sensor can be tuned, using firmware and software, to adjust the sensitivity of the tag, depending on the application. “Our industry already suffers from the false alarm syndrome,” says Axcess president and CEO Allan Griebenow. “The move towards making security networks more productive cannot be done at expense of accuracy.”

Axcess’s system is designed to work in conjunction with RFID tags in employee badges. The system can be set up so that when movement is detected, a signal is sent, but no alarm is sounded if an authorized staff member is also detected near the asset. Security is alerted when an asset is moved by unauthorized personnel.

The motion sensor complements other RFID tags in the Axcess ActiveTag line. The company offers battery-powered RFID tags that are used to identify, locate, and track assets. In addition to the new motion sensor, it also offers tags that sense shock, tampering and temperature.

“We have created an RFID platform and continue to add sensor capabilities with the belief that it becomes a way to make the security network more pervasive,” says Griebenow. “Companies can add intelligence and extend the effectiveness of the security network beyond ordinary capabilities.”

There are a couple of promising markets for RFID sensors. Many third parties are looking to develop sensors that will detect radiation, biological agents and hazardous chemicals. If these can be integrated with a low-cost RFID tag, they could help in homeland defense.

Another area is manufacturing. Axcess sees great potential in offering industrial companies a system that can detect tiny changes in the vibrations and temperature of machines on an assembly line. These would provide an early warning of a potential breakdown, so the machine could be fixed before a malfunction shuts down the entire assembly line.

“The problem with condition sensors has been that you had to develop a costly infrastructure to link the sensors on the machines to a backbone,” says Griebenow. “We can now provide that in a wireless fashion, and we see that as a growth market.”

The motion detection RFID sensors cost about $25 each when purchased in bulk. They operate using a proprietary protocol, but Axcess’s readers offer standard Wiegand output, so they can be connected to most corporate security systems.