For decades, barcodes have been a key technology linking physical objects with automation systems.
Now, however, the growing complexity in manufacturing operations and supply chains, as well as the acceleration in time-to-market requirements, is putting pressure on barcode technologies to do more, to do it faster, and to do it better. Manufacturers need systems that can give them near-real-time visibility into the location and status of parts, assemblies, and finished products. And that visibility must increasingly be extended across the supply chain and product lifecycle -- however complex those might be.
One of the important trends in barcode technologies is the shift from 1D (one-dimensional) printed codes to 2D codes (such as data-matrix and QR codes), which allow for more complex images and thus more embedded data. This is accompanied by a complementary shift from laser-scanning technology to camera-based imagers capable of capturing 2D codes. In turn, the increased volume and complexity of barcode data is requiring more powerful software applications for processing all that data, along with the networking, communications and back-end processing power to handle it. This key technological advancement is extending barcode capability far beyond the traditional track-and-trace functionality.
According to a report by Natick, Mass.-based VDC Research, the line between industrial barcode scanners and machine vision (MV) solutions is starting to blur. Camera-based scanners and area imagers are able to support a broader range of applications beyond simple barcode data capture, including such areas as "image capture and analysis, quality assurance and control, and providing real-time operational visibility," according to one recent report by the firm.
As costs for camera-based imagers are dropping, the capabilities of the technology are continuously improving. For that reason, starting in 2013, said VDC, global revenues from industrial laser scanners in the fixed-position market space began trailing revenues for camera-based solutions. "This is indicative," the report noted, "of the value that imaging solutions offer in fixed-position scanning environments, as well as how rapidly users are gravitating toward these camera-based devices."
Cognex Corp., a manufacturer of barcode readers based in Natick, Mass., said German brake disk manufacturer Alber Gussbearbeitungs-GmbH needed to improve its track-and-trace capabilities during a crucial process for finishing and testing its systems. In the beginning, line workers had to lift the heavy brake assemblies and read and record various embossed part numbers manually. The company was able to automate this process by integrating camera-based readers into the robotic manufacturing systems so that the characters are read simultaneously as the disks are being finished and inspected. This system has increased the speed and reliability of the process and eliminated a strenuous and risky physical task for employees.
Manufacturers in such industries as food-and-beverage and pharmaceuticals have been early adopters of the advanced camera-based systems, given the regulatory and product-liability risks they face.
For example, Cognex said that food manufacturer HJ Heinz was having trouble improving performance and increasing line production at its facility for producing infant milk powder. The company's label verification system could only read 1D codes and was subject to read errors that sometimes resulted in dating errors or incorrect tins being packed. "No read" errors cause costly, time-consuming line stoppages. These problems were eliminated by migrating to an image-based system that can handle 2D codes and that works faster and with 100-percent claimed read accuracy.
Richa Gupta, senior analyst in the auto-ID and data capture practice at VDC Research, told ThomasNet News that manufacturing environments tend to be rough on barcode technologies. For that reason, scanner form factors for factory floors favor rugged stationary scanners.
Print quality is a critical issue in barcode systems, as a poorly printed label can result in a misread or other type of error. "Thermal transfer printers are preferred for manufacturing," Gupta said, "as they can give you a more durable label. In retail stores, codes tend to fade over time, but you can't afford that in an industrial setting." Gupta said he believes that the emerging camera-based systems offer more tolerance for the reading of damaged barcodes.
However, barcode-quality specialist John Nachtrieb of Barcode-Test, a consultancy based in Aurora, Ill., cautioned that "barcode quality is not just limited to the quality of the printed image." Barcode verifier devices are already used in production environments to assure that printed codes are readable. Such verifier devices have to be installed independently of barcode readers, as the two technologies are very different and have never been integrated.
However, according to Nachtrieb, the increasing complexity of 2D barcodes, the data generated by them, and the camera-based imagers needed to read them almost guarantee that quality issues will arise as these advanced scanner technologies roll out in the marketplace. As a result, he asserted, "Verifiers will have to mature as the barcodes they test are maturing."
Photo credit: Cognex Corp.