Mastering traceability with barcode and 2-D matrix code readers
John Stamos, 01-24-2012
Part tracking or traceability is vital because the data is used for production metrics, inventory control, revenue forecasting and process management.
In the automotive industry, for example, traceability is used to help track any defective parts that enter the supply chain back to a precise lot and manufacturer.
To track a part through its full lifecycle, automotive manufacturers mark it with a permanent two-dimensional (2-D) code known as a Direct Part Mark (DPM). 2-D codes are used due to their small size, error correction and the amount of data that can be stored compared to traditional 1-D barcodes. However, due to different marking techniques, the surfaces on which the codes are marked, and real-world environment challenges, DPMs are inherently difficult to read.
One international automotive supplier with whom I work uses barcoded and or 2-D matrix coded transport trays to move the majority of its components. Being able to read these codes reliably is extremely important because these trays sometimes cover enormously long distances in their productive life and form an important basis of internal logistics.
Historically, the company had employees laboriously reading the codes with handheld scanners, which updated the location of the transport tray, and this is how the parts required in the production process are updated in the logistics system. Today, the process has been automated using In-Sight® 5605 high-resolution intelligent vision systems from Cognex. The vision system recognizes and reads the codes on tall stacks with different numbers of trays within a few milliseconds – making the process significantly faster and eliminating the potential for errors in manual work.