The miniaturization of consumer products presents a double challenge to machine builders. Not only must their machines produce smaller products quicker and at lower cost. They also need to provide complete traceability of end-users' products.
Increasingly, machine builders are using radio frequency identification (RFID) technology to meet both challenges. RFID information helps manufacturers enhance product quality while achieving lean manufacturing, just-in-time delivery and regulatory compliance.
One such company is Calmation Inc., based in Simi Valley, CA. Calmation designs, builds and integrates custom machines for manufacturers in a wide range of industries.
Several of the company's customers run manufacturing lines that produce a high volume of consumer goods and require 100 percent paperless traceability. Recently, Calmation developed an automated assembly workcell with these capabilities.
The workcell is based on Rockwell Automation's Ethernet Industrial Protocol network, which Calmation has integrated with Balluff Inc.'s IO-Link for greater functionality. It also features a Staubli robot that performs pick and place.
The IO-Link provides open, point-to-point communication between the control unit and sensors or actuators. It works with an unshielded industrial cable, enabling manufacturers to easily integrate RFID, input-output nodes, pneumatic valve banks and stack lights.
Calmation used the link to integrate three Balluff RFID readers on the cell's build pallet. The readers transmit product serial numbers to a PLC, which then tracks each product (via serial number and additional process data) throughout each step of production. This information is written back to RFID tags attached to an offload carrier at delivery.
Calmation likes that the IO-Link enables manufacturers to track RFID data in two ways. The first is centralized tracking, where all data is stored in a central computer, and the RFID system is used only for part identification. This read-only system is very similar to barcoding, but 100 percent reliable.
With decentralized tracking, data per part is stored on the RFID tag and written to the tag at each workstation. This read-and-write system ensures that the data always stays with the part throughout production.
Calmation also integrated Balluff add-on instructions into the workcell's operating software. These instructions enable end-users to quickly connect their cells with other Rockwell Automation platforms. They also minimized the need for Calmation to outsource engineering work when developing the workcell.