RFID on the Production Line

Engineers are using radio-frequency identification (RFID) to enable plant-floor applications, often with help from databases and software. Here's how RFID works and gives users real-world advantages and savings, such as better visibility控制工程网版权所有, tracking, and quality control.

Control Engineering Staff

AT A GLANCE

• Evolving RFID technologies
• Tags shrink over time
• Databases allow RFID to aid control

Talk is cheap, but radio frequency identification (RFID) syst

One of these top 100 suppliers is Wells' Dairywww.cechina.cn, which provides Wal-Mart with Blue Bunny ice cream and novelties. Wells' reports that it's the largest U.S. family-owned Dairywww.cechina.cn, and that it operates the world's largest ice cream manufacturing facility, located in LeMars, IA, which can run up to 160 hours per week.

While many suppliers try to comply with new RFID rules by adding tags just before shipping, Wells' decided to seek benefits and savings by implementing its RFID system early in its manufacturing process. Brad GallesCONTROL ENGINEERING China版权所有, Wells' process controls manager, began working with the dairy's automation supplier, Rockwell AutomationCONTROL ENGINEERING China版权所有, on a pilot project in mid-2004. Their in-house-developed solution uses Allen-Bradley 1756 EWEB modules for ControlLogix to process data from Alien Technology's RFID readers and 915-Mhz, 96-bit Squiggly tags (see illustration, at left).

These RFID tags are written onto by the antenna-reader, and then applied to each two-bucket case as it's wrapped, at 30 cases per minute. The tags are read again up to four times as the cases are quick-frozen and