Packaging inspection and text detection
Vision Verifies Packaging at Tip Top Ice Cream
How do you guarantee the correct packaging is being used for the ice cream being produced?
Tip Top is New Zealand's leading ice cream company and produces around 50 million litres of ice cream per year out of facilities in Auckland and Christchurch. For their popular 2L ice cream tubs Tip Top use state-of-the-art packaging design, with colourful graphics - all designed to make the product look as good as it tastes. A recent decision to remove the barcode from the lid of the container introduced a challenging food safety concern: How to guarantee the correct packaging is being used for the ice cream currently in production? A packaging mix-up, if undetected, could lead to a costly product re-call. This, combined with food allergy risks, makes for a potentially serious food-safety situation.
Cognex vision meets the challenge
The solution provided needed to be flexible and scalable in order to allow for future changes of graphics, colours and products. In addition to all of this environmental conditions were prone to change in terms of lighting and temperature factors.
The system also needed to be simple insofar as personnel with limited vision experience could be trained easily to work independently with the programme and have the possibility to make simple changes without compromising the reliability and success of the system.
Machine vision was the only possibility for such high speed production. Cognex partner, ControlVision, supplied a solution to both the Auckland and Christchuch production sites based on Cognex In-Sight® vision systems with PatMax® pattern matching technology. An advantage of the Cognex In-Sight vision systems and lighting is the fact that they are designed to cope with a harsh caustic wash-down environment.
Machine vision with an eye for detail
The nature of the application was perfect for the robust pattern matching features of Cognex In-Sight and PatMax. Pattern matching on unique features in artwork provides a fail-safe method of verifying the correct packaging for the appropriate product. PatMax is tolerant of variations in product presentation angles, and can even cope with perspective distortion. The capacity of PatMax to acquire a sufficient amount of detailed information ensures not only zero defects but also a negligable rate of false rejects.
Verifying correct packaging on 2L ice cream at up to 180 packs per minute
The top and side of the container are searched for a taught unique feature, e.g. the product name graphic. Using PatMax, the programme memorises and recognises an area of text and certain aspects of the label as well as its positioning on the lid.
If a positive match can't be found, then the container is automatically rejected at a down stream reject station. The capacity of PatMax to acquire a sufficient amount of detailed information ensures not only zero defects but also a negligable rate of false rejects.
There is no need for any complex parameter configuration which ensures ease of use and long term flexibility. New products are quickly set-up with a wizard that takes maintenance staff through the steps required to teach a new pattern template. Operators select the product at the beginning of a production run using a simple software interface provided by ControlVision's Recipe Manager software.
The simplicity and reliability of the solution permits Tip Top to maintain a high level of production without compromising quality.