Meet the robot that could one day harvest Michigan’s apple orchards

SPARTA, MI — The tubular robotic arm reaches through the leaves with its target in sight. With a sound like a vacuum cleaner sucking up a stray pant leg, a dark red Gala apple finds itself in the machine’s clutches.

There is a sudden movement, a snap of fingers. The arm retracts, depositing the fruit into a padded bin, where it is carefully transported through the bowels of the machine. Within seconds, the harvester is already on its way to its next succulent prey.

At Schwallier’s Country Basket orchard in western Michigan near Sparta, researchers and growers hope they are on the verge of a mechanized revolution in the apple industry, driven by rising production costs.

“They’re really suffering from labor shortages and labor costs,” said Zhaojian Li, an engineering professor at Michigan State University who helped lead the development of the automated harvester that sucks apples off Schwallier’s trees during a demonstration in early September.

“There is huge demand, not only in Michigan but also in Washington state,” Li added, referring to some of the country’s top apple-producing states.

Learn more: Michigan’s apple season is coming early this year. Find out when to find your favorite variety

Unlike wheat and corn, automation of harvesting specialty crops, such as fruit trees, strawberries and asparagus, is less developed, leaving little product commercially available to farmers, he said.

Apples are picked mainly by hand, as they are easily damaged, especially if they are to be sold in fresh markets.

That’s the case for much of Phil Schwallier’s crop. The fourth-generation fruit grower’s produce ends up in grocery stores like Walmart and Meijer through middlemen who pack and market the apples, he said.

Schwallier, who worked as a horticultural agent at MSU for 42 years, welcomes the university’s research team, led by Li and Renfu Lu, a researcher with the U.S. Department of Agriculture’s Agricultural Research Service and an agricultural engineer, to his orchard.

The orchard relies on seasonal workers, many of whom come from Mexico, he said. But more apple growers are sounding the alarm as wages for foreign workers on temporary government visas rise to levels they say threaten their livelihoods.

Learn more: Michigan orchards rely on migrants to pick apples. But wages continue to rise.

This year, Schwallier and other apple growers signed a letter to bring the problem to the attention of federal leaders. “Our industry is in crisis,” it reads.

Labor costs account for 56 percent of per-acre expenses for Michigan apple growers, compared with 12 percent for all farms, according to figures from the Michigan Apple Committee, an industry group. Average labor rates can be as high as $37 or $38 an hour, when transportation and lodging costs for migrant workers are factored in, Li said.

“I don’t want to replace my workers, but it’s getting harder and more expensive,” Schwallier said, adding that he envisions a future where robots could harvest the tops of trees, saving lower branches that are easier for human workers to reach and avoiding the use of ladders.

“The robot does not get tired and works 24 hours a day, 7 days a week,” he said.

For Schwallier, the technology can’t come soon enough, because labor costs could force his farm to abandon the orchards if they’re not profitable. Visitors get angry when they see apples left on the tree, but he can’t afford to pick them if the price is higher than the sale price, he said.

However, Schwallier does not expect automated orchards in the near future.

Research into robotic apple harvesting actually goes back decades, starting with concepts that involved shaking trees and grabbing the fruit, a risky proposition because of the damage the technique can cause to apples, Li said.

Li has been working on the MSU-USDA robotic harvester since 2019 and says his team has funding for four more years of research.

The machine’s goal is to work in “above average” orchards, structured and pruned in a way that is more suitable for robots. It may not work in older orchards. The machines are not intended to strip a tree, but to harvest about 70 to 80 percent of the fruit.

One of the main challenges, Li said, is the perception system, the robot’s eyes, which identify the fruits and their location in space. In orchard environments, there are leaves and branches that get in the way, as well as challenges due to outdoor light conditions.

The machine’s dual suction arms do have advantages, however, because they allow the picker to tolerate some inaccuracies in locating targeted fruit in 3D space. The team is making good progress, Li said, but the robot still struggles to handle clusters of fruit that are close together and large blockages caused by foliage and branches.

The Michigan research team is not alone in trying to solve the puzzle.

A California startup, advanced.farm, is working on automating apple harvesting with a machine that also uses suction cups. Israeli robotics company Tevel Aerobotics has developed a fruit picker that uses autonomous flying drones to pick apples from trees.

The goal of the MSU and USDA team is to create a platform that can implement sorting in the field, where fruit is separated based on size, color and damage, Li said. Currently, farmers pay packing and storage fees to third parties who do this work, so doing this task at the orchard could be another cost savings.

“The least expensive way to sort apples is to sort them on the tree,” Schwallier said.

Other farmers — at least those who could spare the time during the busy six- to eight-week harvest period — were on hand at Schwallier’s Country Basket as MSU graduate students helped demonstrate the local robot, towed on a Kubota tractor.

Some producers say the technology still needs to get faster and more efficient, but Schwallier said his peers are very interested in the technology.

“I’m really happy they’re working on it, and I’m really happy they’re working on it here in Michigan where we can see it,” he said.