see, but the unique ID on the bottom of the container is visible through the transparent shrinkwrap film.

Omega Design implements this track-and-trace approach with a single unscrambler that can maintain full control over each container—its speed, height and orientation—while passing under the print head and over the verification and rejection stations. The unscrambler accepts bulk bottles and orients them sequentially on the production line. It prints and verifies a unique ID on the bottom of every empty container. This unique ID contains enough information to keep track of the container temporarily on the packaging line.

Once a larger, permanent and fully serialized label is applied to the container, a camera and serialized software management system put the label code and bottom code in sync. When it’s time for final packaging, the shrink bundler groups and wraps the specified number of containers into a bundle. A robot lifts each bundle and passes it over another ID reader that identifies the containers in the bundle. A new label is then placed on the bundle that is linked to each package in the bundle. A parent-child relationship is developed.

Demanding application

The ID reader used on the unscrambler must accurately read Data Matrix codes while keeping up with a line that runs at 50 to 300 bottles per minute. The bundler provides an even more challenging application because the ID reader must read all of the bottles in the bundle with one image. “We picked Cognex 5000 Series vision systems for this application because our experience shows that they provide the required accuracy for reading 2D Data Matrix codes,” said Scholes.

In-Sight vision systems incorporate Cognex IDMax Data Matrix code reading software, based on PatMax technology, to handle a range of degradations to the appearance of the code and provide robust and reliable decoding under all conditions. Omega Design uses the In-Sight 5410 ID reader on the unscrambler and the higher performance In-Sight 5603 on the bundler application. Cognex also provides a full line of fixed and handheld ID readers that can be used to verify the origin of the bottle at any point in the supply chain.

Shaun Keperling, of Omega Design, used Cognex’s spreadsheet-based programming interface to overlay images of the 12 inspected codes, provide pass/fail indications for each code, and also provide a pass/fail for the entire bundle on the user interface. “The spreadsheet interface is flexible,” Keperling said.

The program kicks off when the vision system receives a digital signal from the programmable logic controller (PLC) that a bundle is in position for inspection. The program first captures the image of the bottom of the bundle containing a dozen 2D codes. Then, 12 different inspection tools are run to read the codes. If all of the codes are read, then a digital output is sent back to the PLC. The PLC instructs the robot to place the bundle on the pass conveyor. The vision system uploads the container IDs to a computer where they are managed by track-and-trace software. If the inspection fails, the controlling PLC instructs the robot to reposition the bundle two more times and re-triggers the inspection. If these inspections also fail, then the bundle is channeled to a reject chute.

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