Teaching robots to cut and sort meat, which involves soft material and variability, he said, "it's the most challenging operational environment you can find." The low temperatures at meat plants, kept cool for food-safety reasons, pose more hurdles for robotics, as does blood splatter, industry officials said.

Inside Tyson's Arkansas robotics lab earlier this year, one room included a robot with a mechanical arm mounted inside a glass box, resembling an arcade crane game. With the push of a button, the robot's arm dumped three cups of multicolored beads onto a tray, then rapidly grabbed each one and sorted them by color in less than 30 seconds.

Tyson's technicians are trying to teach machines to recognize and quickly adjust to differences in meat coloration and shape, part of what executives say makes meat processing harder for machines than, say, assembling cars from uniform, manufactured components.

In meat plants, "our parts are infinitely variable," said Marty Linn, previously the principle engineer of robotics for General Motors, who joined Tyson last year to help direct its automation efforts.

European meat plants have incorporated more automation than their U.S. counterparts, using lasers and optical eyes to read cuts of meat on a conveyor belt and send them to different departments to be packed, weighed and shipped. The technology means a single worker in plants in Sweden, Denmark and France does the work of eight or nine workers in U.S. plants, though the operations run at a slower pace, said Mr. Lauritsen, the union official.

Mr. Lauritsen said boosting automation at U.S. meatpacking plants needs to be done thoughtfully so job losses don't devastate the communities they sustain.

"If you take half the jobs out of Worthington, Minn., and Denison, Iowa, you take away 2,000 jobs and the payrolls that come with them," he said, referring to two towns with meatpacking plants. "You've crippled those communities."

Tyson's Mr. Banks said that workers are in no danger of being replaced broadly by robots soon. Workers whose jobs are automated can be moved into other, open positions, so layoffs aren't needed, he said. Robots can improve employee retention, he said, by making jobs more skilled and less strenuous.

Mr. Banks said that the technology is needed to relieve bottlenecks in Tyson's plants, where lack of skilled workers in critical jobs can slow overall production. To solve one such problem, he said, Tyson designed a water-jet cutting system capable of carving up chicken breasts more precisely than humans can. Many Tyson chicken plants now are using the system to develop new products that they couldn't make using human labor, he said.

Automation "is something we think is going to be revolutionary for our business," said Doug Foreman, Tyson's director of manufacturing technology, who has designed meat-cutting equipment for decades. "We are on the cusp of a significant rollout."

Write to Jacob Bunge at jacob.bunge@wsj.com and Jesse Newman at jesse.newman@wsj.com