This four-camera, machine vision setup uses specialized software to develop a digital 3-D image so that the entire label of each is checked at high speeds. Photo courtesy of Cognex Corp.

People and packaging production lines are not always perfect. When a mistake inevitably occurs, the best kind of problem is one that is detected, identified and corrected. Helping operations check, detect and respond quickly, effectively and continuously can be done by a range of inspection methods, including those that take a literal look at-and inside-packaging: machine vision and X-ray systems.


For Carl Bonnan, general manager at Heuft USA Inc., automated inspection is all about protection: “More companies are starting to invest in technologies to better protect the consumer in addition to providing increased protection to their brands.”

 

He points to the effects of recent food safety legislation. “Inspection technology will play a key role in food safety, especially now that the Food Safety Modernization Act was recently signed into law [by President Obama in early January 2011],” he says. “We anticipate more demand for machine vision applications, including label verification, code scanning, contamination inspection and data collection systems, to support quality assurance record compliance. We also anticipate more demand for automated sampling systems.”

 

“Food safety and general product quality have become increasingly important to our customers,” says John Duffin, vice-president at Acquire Automation, an independent automation solutions provider that integrates vision technology from Matrox Imaging. “More stringent requirements with quality and accurate labeling have made it not only economical, but nearly essential in guaranteeing 100% accuracy. Many customers are also looking for that competitive edge-taking quality to the next level for the brand.”

 

That can mean a wider breadth of protective measures. Duffin notes that vision inspection has made considerable inroads within the food and beverage packaging market in the past few years, and is deployed throughout customers’ entire packaging processes. Inspections may now include material and component check-in, product fill level, label verification, lot and expiration date verification, label quality and  position, cap and closure inspection, allergen and label mix-up prevention, product counting, product gauging, 1-D and 2-D bar code verification, color verification, and case count and orientation.


 

John Petry, Cognex’s vision software marketing manager, cites a trio of trends in inspection: product quality, traceability, and correctness. As the fastest growing driver among the three, correctness is closely associated with product recalls and lawsuits related to improperly labeled products including for allergens.


 

“Another big driver within correctness is the increasing use of bar codes, and especially 2-D codes, on food labels,” Petry says. “Companies need to ensure that the code matches the product label, since the code is what’s used for tracking, stocking and pricing the product.” OmniView uses four cameras and software to produce full-surround, 3-D rendering and subsequent analyses. Notably, it was developed for food and beverage markets about three years ago in response to customer requests surrounding liability issues.




Jam and fruit spread maker Zentis in Germany has had three production lines of its jarred products examined by X-ray inspection systems since mid-2008. Zentis reports that the systems have detected faulty jars during use. Photo courtesy of Heuft.

The keen interest in label inspection is not coincidental. Product labeling mishaps account for 40% of recalls, according to Food and Drug Administration figures, notes Brian Mack, CI-VisionOEM sales manager.Mack points to a triumvirate of technology improvements associated with vision systems in the past few years: greater reliability, improved robustness, and higher rates. He points to the standardization on low-maintenance LED lighting as a boon for reliability and robustness. Computer processing power has also raised capabilities.

“Systems must be able to keep pace with ultra-fast production lines,” he explains. “Five years ago, the high end was 500 parts per minute. Now systems can handle rates above 1,000 parts per minute to 4,000 per minute.” He also points out that even as camera resolution is increasing, the size is shrinking so they can be installed into tighter spaces. Through the Gigabit Ethernet (GigE) networking standard, cameras can be connected across longer distances to provide additional flexibility and reach. GigE also permits easier, cost-effective expandability.

Acquire’s Duffin concurs on the need for speed: “Increased processing power is allowing for more inspections at higher rates and with a smaller footprint.” Yet, along with that compact sophistication, systems are becoming easier to use, he adds.

Mark Langridge,SICK’s food and beverage national sales and market manager, sees an increase in inspections related to a Six Sigma approach. Implementation is done using equipment that provides real-time information on product size, weight and dimensions.

“This information initiates a process improvement plan to minimize defects during production to reduce waste and improve quality,” he says. “In packaging, there is a greater need for inspection systems, ranging from identifying product defects to ensuring that the packaged product’s history and future is known. This could be as simple as reading a lot code to identifying a 2-D Data Matrix code and decoding it at various points in the process.”

Food processors are increasingly using X-ray inspection for quality control, reports Kevin Jesch, manager of inspection systems forHeat and Control. Packaging applications include finding under-filled packages and damaged product to help reduce customer complaints. 

X-ray inspection is based on evaluating density throughout the product and package, including through thick foil pouches and cans.

“Ishida X-ray systems can inspect virtually any packaged product,” Jesch points out. Contaminants embedded within the product can be easily detected, down to 0.3 millimeters in size using new technology, he adds.From small problems to big ones, inspection systems provide a viable solution to imperfection. F&BP

For More Information

Acquire Automation
317-849-3350;www.acquire-automation.com

Cognex
508-650-3000;www.cognex.com

Heat and Control
800-227-5980;www.heatandcontrol.com

Heuft USA, Inc.
630-968-9011;www.heuft.com

Matrox Imaging
800-804-6243;www.matroximaging.com

Mettler Toledo CI-Vision630-446-7700;www.mt.com/ci-vision

SICK Inc.800-325-7425; www.sickusa.com