Robotic gripper made from coffee-filled balloon

But to do just just that, researchers from Cornell University, University of Chicago and iRobot bypassed traditional designs based around the human hand and fingers, and created a versatile gripper using ground coffee and a latex balloon.

Hod Lipson, Cornell associate professor of mechanical engineering and computer science, said that the device has been named a ’universal gripper’, as it conforms to the object it’s grabbing rather than being designed for particular objects.

In use, a balloon filled with ground coffee is attached to a robotic arm. The coffee-filled balloon presses down and deforms around the desired object, and then a vacuum sucks the air out of the balloon, solidifying its grip. When the vacuum is released, the balloon becomes soft again and the gripper lets go.

Heinrich Jaeger, a physicist at the University of Chicago, said that coffee is an example of a particulate material, which is characterised by large aggregates of individually solid particles. Particulate materials have a so-called jamming transition, which turns their behaviour from fluid-like to solid-like when the particles can no longer slide past each other.