Octopus-inspired robot ‘hands’ delicate enough to grasp a tomato

Soft Robotics' grippers can pick up a variety of shapes.
Soft Robotics' grippers can pick up a variety of shapes.

This is a robot that loves its veggies.

In one corner of a noisy lab in Cambridge, a goofy-looking robotic arm has been moving vegetables back and forth on a party tray for days. Bright-blue fingers curl like tentacles around a piece of broccoli and carry it over to an adjoining compartment. The tentacles flex in midair, then move a piece of ginger one spot over. Then a quince, then a small pepper — and repeat.

This is ground zero at Soft Robotics, a company that wants to get its specialty robot hands all over your food.


Soft Robotics founder and director Joshua Lessing (left) and Matthew Driscoll demonstrated tentacles the company designed to handle delicate objects. (Photo: Justin Saglio for the Globe)

Last week, the year-old startup announced a partnership with Heinzen Manufacturing International, a California company that makes sorters, washers, and chopping equipment for produce manufacturers that ship cut fruit and bagged and washed greens to stores like Costco.

Along with an assortment of conveyer belts and slicers, Heinzen intends to offer clients a robotic arm equipped with the speciality gripper made by Soft Robotics.

“They’re basically going to be like the grasp of the human hand,” said Joshua Lessing, the founder and director of R&D at Soft Robotics, who hand-crafted some early prototypes.

Even the best robots today tend to be a little klutzy, and most metal robot hands will crush a cherry tomato like a potato chip. Also, metal fingers require a huge amount of code to merely get near an object, then must adjust their grip so that it’s not too hard, and not too soft. Instead, Soft Robotics uses a combination of unique design — tentacles, not fingers — and a careful choice of materials, opting for elastic polymers over metal.

And while other robots must know the exact size, shape, and weight of an object to move it, Soft Robotics’ robotic hands can use the same programming to grab anything in their path, whether that’s a 10-pound kettle bell or a golf ball. The grippers simply inflate and deflate. This has allowed the company to forgo fancy cameras and sensing technology for cheaper gear.


But Soft Robotics didn’t start out trying to change the future of food.

The technology has roots in the Harvard lab of George Whitesides, a chemist whose vast array of inventions includes tiny, inexpensive paper-based blood tests and new manufacturing techniques for electronics.

Whitesides was inspired to build a new kind of robot after watching a YouTube video of an octopus squeezing through a tiny hole. He encouraged his team to build a bot that mimicked that flexibility, and the team in 2011 showed its first prototypes: flat, elastic quadrupeds that crawled along the floor, powered by air.


A version of the arms are tough enough to hold a kettlebell. (Justin Saglio for the Globe)

In 2013, Soft Robotics was born, receiving funding from the Defense Advanced Research Projects Agency to make soft surgical tools. The goal was to develop items a surgeon could use to maneuver delicate tissue and organs, in lieu of steel tools.

“DARPA wanted us to work on combat trauma,” Lessing said. So he built tools for surgery, and ran experiments with cadavers, proving his soft tools would work.

But the way Lessing remembers it, some months into that pursuit, chief executive Carl Vause wandered into the lab with a question: Could the robotic grippers pick a piece of produce, like a strawberry or a tomato? That was a pivot point. Vause made the case that the produce industry was a vast market that robotics didn’t yet serve.

While industrial robots have long been fixtures in factories, toiling solo on assembly lines, a swath of industries are looking for robotic collaborators that can work safely alongside humans. They also want robots that are versatile. Last month, Amazon hosted a “picking challenge,” offering $26,000 in prize money to researchers who could build robot grippers that could grab many different things, one after the other — as would need to be done in a warehouse.

Soft Robotics has since shifted its focus from surgery to sorting veggies. Lessing told Vause: “If you can move a spleen, you can pick a tomato.”

And tomato growers are taking note. Among the companies that have expressed an interest in Soft Robotics is greenhouse grower Nature Fresh Farms, of Toronto. It’s looking for a robot hand that can sort, size, and pack beefsteaks without bruising.


Eat your veggies. Or this robot will. (Photo: Justin Saglio for the Globe)

The fact that the robot’s fingers can be snapped off and sterilized adds to the appeal, said Curtis Anderson, a technologist for Nature Fresh. Contamination is the major factor that is driving produce manufacturers to automate. The Food Safety and Modernization Act put a focus on preventing illness, and for many companies, this means finding ways to clean up the factory floor.

Assembly lines for produce are typically staffed by humans doing repetitive work in rooms chilled to 34 degrees to keep the food fresh. For example, as fruit is cleaned and cut, it falls to a person to pack each piece. “If you look at a party tray with five components, it’s going down the assembly line touched by 20 people,” Heinzen chief executive Rudi Groppe said.

Nimble robots could work faster, and cleaner. He said that solves a longstanding question: “Where were the workers’ hands before?”

Nidhi Subbaraman writes about science and research. Email her at [email protected]
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