Industrial-strength RFID penetrates metals

April 29, 2009
Contributing Editor Sheila Kennedy demonstrates how signals from industrial-strength units can even penetrate metals.

Radio-frequency identification (RFID) devices are popular in the industrial sector for their ability to streamline asset identification, cargo tracking, inventory management and maintenance. Recent advances allow RFID to play a role in ways not previously possible.

Read and write through metal: RFID technology hasn’t traditionally been well-suited to harsh environments because conventional surface-mounted tags can be damaged. RFID tags and readers that allow information to pass through metal alleviate this difficulty. Switzerland-based MBBS SA has patented its METALuCID tag and reader technology that reads and writes through as much as 1 mm of metal. The hermetically sealed, 125 kHz tags withstand temperatures to 464 ºF, pressures to 2,000 bar (29,000 psi), sterilization, acids, aggressive chemicals, sandblasting and shocks.

The standard or customized METALuCID RFID tags are completely housed and packaged, and can be integrated during manufacturing or retrofitted to existing equipment to improve maintenance and traceability in rugged conditions. When hermetically sealed within a metal tool or component, the tags become a permanent and durable part of an RFID system. Metal-encased adhesive or tie-wrapped tags are suitable for mounting on assets such as pressurized containers. MBBS also has designed fully sealed tags that deter counterfeiting by self-destructing if the factory-sealed container has been opened.

MBBS tag technology operates at frequencies below 135 kHz, which allows the electromagnetic fields to penetrate the metal layer. The passive tags don’t require an internal power supply because they’re energized by the read/write module, and they use a flat, miniature air coil as an antenna. The portable readers are designed with standards-based emitter and receiver technology that operates with the through-metal tags and most other low-frequency tags.

Monitor hazardous materials: The U.S. DOE monitors tens of thousands of nuclear material packages to ensure accountability, safety, security and the health of workers, the public and the environment. What the DOE lacked was real-time visibility into the status and condition of the material containers during storage and transportation. A new RFID system is capable of simultaneously monitoring these drums around the clock and triggering an alarm when a loss of seal, sudden shock, rise in temperature or humidity, or other abnormal situation occurs that affects drum integrity.

Although designed for nuclear materials, the technology developed by scientists at Argonne National Laboratory is applicable to other hazardous or valuable materials. It tracks information about the materials in real time, monitors the environmental and physical conditions of containers, and decreases the need for manned surveillance. Integration with GIS, GPS and general packet radio service technologies enhances the tracking of package location and movement.

The system’s active transponder RFID tags feature on-board memory and long-life batteries that last more than 10 years. Its readers collect information from the tags and the encrypted data are sent to a control computer where software transforms them into actionable information. The current status and history of each container is constantly communicated through a Web-based, secure network accessible only to authorized users. Argonne’s technology, which is expected to be patented, is demonstrated in a video:

Track items globally: Tracking assets outside a typical RFID infrastructure or around the world might soon be easier because of a new tag that combines active RFID, GPS and satellite communications. Numerex Corp. and Savi, a Lockheed Martin subsidiary, partnered to develop the intelligent hybrid ST-694 GlobalTag. It’s designed to enable spot-level and in-transit tracking for transport vehicles, container shipments and other large and valuable equipment throughout the global supply chain.

The ST-694 GlobalTag tracks assets and containers beyond the reach of RFID readers by switching automatically to satellite communications when the reader loses contact. The developers intend the tag to provide real-time visibility on a near-global basis, even in harsh conditions. It’s currently being tested for government use, but the public sector and commercial industries also will benefit from the technology.

Ensure data security: To help mitigate the risk of unauthorized or inadvertent RFID data access, a new tag data security technical report is available from the International Organization of Standards (ISO). ISO/IEC TR24729-4:2009 was developed based on guidance from AIM Global’s RFID Expert Group to help RFID systems designers determine potential threats to tag data security and tag-to-reader communication, and the countermeasures available to provide RFID data security.

E-mail Contributing Editor Sheila Kennedy, managing director of Additive Communications, at [email protected].

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