Watch a robot peel a squash with human-like dexterity

A robot that peels vegetables in the same way that people do demonstrates a level of dexterity that could help move delicate objects along a manufacturing line.

Prototype robots are often tasked with peeling vegetables to test their ability to carefully handle awkward objects. But these challenges are usually simplified, such as the vegetable being fixed in place, or only testing single fruits or vegetables, like peeling a banana.

Now, Pulkit Agrawal at the Massachusetts Institute of Technology and his colleagues have developed a robotic system that can rotate different types of fruit and vegetable using its fingers on one hand, while the other arm is made to peel.

“These additional steps of doing rotation are something which is very straightforward to humans, we don’t even think about it,” says Agrawal. “But for a robot, this becomes challenging.”

First, the robot was taught in a simulated environment, receiving an algorithmic reward for a proper rotation and a punishment if it rotated the wrong way or not at all.

Next, the robot was tested under real-world conditions by tasking it with peeling fruits and vegetables such as a pumpkin, radish and papaya. It used one hand to rotate the produce, using feedback from touch sensors, while a human-controlled robot arm did the peeling.

The algorithm struggles with smaller, more awkwardly shaped vegetables, such as ginger, says Agrawal, but the team hopes to expand its capabilities.

Grasping and reorienting objects are challenging tasks for any robot, and the speed and firm grip of this one is impressive, says Jonathan Aitken at the University of Sheffield in the UK. It could be useful in factories where objects have to be moved from one machine to another with the correct orientation, he says.

However, it is unlikely to be used in an industrial setting for peeling vegetables because other approaches already exist, such as automatic potato peelers, says Aitken.