Robotic hand with soft touch able to select ripe tomatoes

ITHACA, New York: Researchers at Cornell University have developed a soft robotic hand with a touch delicate enough to sort tomatoes and find the ripest one.

Most robots achieve grasping and tactile sensing through motorised means, which can be excessively bulky and rigid. The researchers have devised a way for a soft robot to feel its surroundings internally, in a similar way as humans do.

The group led by Robert Shepherd, assistant professor of mechanical and aerospace engineering and principal investigator of Organic Robotics Lab, has published a paper describing how stretchable optical waveguides act as curvature, elongation and force sensors in a soft robotic hand.

Doctoral student Zhao Huichan is the lead author of the study.

Explained Zhao: “Most robots today have sensors on the outside of the body that detect things from the surface. Our sensors are integrated within the body, so they can actually detect forces being transmitted through the thickness of the robot, a lot like we and all organisms do when we feel pain, for example.”

The soft robot hand is a step forward for the growing field of soft robotics — the kind of technology that’s already used in warehouses to handle food or other products. But it also holds promise for better prosthetics, robots to interact directly with people or with fragile objects, or robots to squeeze into tight spaces.

Added Zhao: “Our human hand is not functioning using motors to drive each of the joints; our human hand is soft with a lot of sensors ... on the surface and inside the hand. Soft robotics provides a chance to make a soft hand that is more close to a human hand.”

“There’s a tremendous unmet need here,” says Joshua Lessing, director of research and development at the company Soft Robotics that is already making products using soft robotics. The company’s soft robot grippers are used in factories to sort and pack food like tomatoes or baked goods and to pick up things that people order online.

Zhao estimates her soft robotic hand could be made for under US$50. — Cornell News

Most robots today have sensors on the outside of the body that detect things from the surface. Our sensors are integrated within the body, so they can actually detect forces being transmitted through the thickness of the robot, a lot like we and all organisms do when we feel pain, for example. — Zhao Huichan, Doctoral student