Retrofitting an apple packing line
A new vision sorter helps Apple King put up a more consistent pack.
These images are from one apple. The white apples are infrared images.
A Yakima, Washington, grower-packer operation wanted to upgrade its optical sorting capability but didn't want to make expensive changes to the entire line. By retrofitting the outdated optics with a new system, color and size grade adjustments can now be made quickly with a few computer keystrokes.
Mike Saunders, Apple King LLC partner, is more than pleased with the new vision optics they had installed last December. "The differences between the new vision technology and our old system are exponential," he said. "Before, if we wanted to change color parameters on smaller fruit, our system would change color on the larger fruit differently, and we couldn't control the whole line the same. Now, I can stand over the lanes and if I don't like the color I'm seeing go by, we can control one lane at a time if we wish."
Saunders said that no significant upgrades had been made to their Aweta line since its installation in 1992. The cameras used for sorting were obsolete and could no longer be replaced.
"We didn't need a whole new packing line, but we wanted to upgrade our sorting capability. So we did a retrofit," he said, adding that the cost of the new optical system was about equivalent to what it would cost to upgrade one lane.
The main reasons for upgrading the optical sorters were to be more efficient, eliminate downtime when making line changes, do a better grading job, and provide a consistent product, said Apple King partner Ray Keller.
Saunders emphasized the importance of consistency. "It's about having a consistent product," he said. "Our customers noticed a difference right away in our grading. The pack is so consistent, especially the bicolored varieties. And, there's also less stress on us."
Apples move underneath a bank of cameras that capture six images
of each apple to determine color and size.
The new optical system installed at Apple King was developed by Ellips, a company from the Netherlands that specializes in vision technology. The Good Fruit Grower interviewed Erwin Bakker, one of the founders of the company, during a recent visit to Apple King to discuss Ellips's new external defect sorter.
Ellips began to mesh together computer and camera technology some 20 years ago when the company was asked to develop sorting capability for pears. Other commodities soon followed, including peppers, potatoes, tomatoes, rootstock, flowers, asparagus, apples, and other fruits and vegetables. "In regards to packing lines, we don't try to do it all, but only specialize in the vision technology," Bakker said. "We specialize in taking pictures of the fruitnot in the steel railing, electrical systems, and the belts, conveyors, and such, of a packing line."
Bakker noted that Ellips provides vision sorting technology to 15 packing line manufacturers. The retrofit at Apple King was the first made by Ellips in the United States, although several optic retrofits have been made in Europe.
Apple King production line manager German Lopez said the Ellips system is easy to use and required three to four hours of training to learn how to set the size and color parameters. As an apple passes underneath one of ten cameras set up over the nine lanes, infrared and color cameras take high resolution imagessix for each piece of fruit. Software algorithms are used to determine weight, diameter, and color properties for fruits or vegetables.
Lopez said that he has preset programs for color and background color of each variety, but that he can fine-tune a setting if need be. For sizes, a range in grams is selected for each grade. For example, he could select 123 to 130 grams for a certain size.
A laptop computer stationed out by the packing lanes can be used to make any changes, saving supervisors time from having to run back to the main computer control room to make a grade adjustment.
Ellips recently expanded its vision technology to offer external defect sorting. The partners at Apple King are considering adding the external defect sorting to their line. An external defect sorter would significantly reduce labor costs at Apple King by replacing many of the human eyes and hands that are currently used for defect sorting. The Ellips defect sorter is based on the same concept as its vision sorting technology, but requires more cameras to make sure the cameras see all of the fruit.
Bakker noted that with the current technology at Apple King, the cameras see about 80 percent of each piece of fruit. "But for effective defect sorting, you need to see about 99 percent of the fruit," he said, adding that the cameras must be able to see all angles. The technology would be able to sort for quality defects like blemishes, mold, punctures, and scratches.
For defect sorting, the Ellips camera system takes 40 images of each piece of fruit. To implement such a change, Apple King would need to add about 26 cameras to their current setup, representing a sizable investment to their nine-lane packing line. Saunders estimated that each lane would cost about $17,000. The advantage to the investment would be improved labor efficiencies.