- A new stress-ball-like gripper delicately grasps a wide range of objects.
- A current model of the gripper uses coffee grounds and glass beads, wrapped in a rubber membrane.
- Scaled up, a one-meter-wide gripper should be strong enough to lift steel beams.
The sand-filled rubber stress ball sitting on your desk could be the key to a new generation of robotic grippers, according to a new study. The new gripper, which uses a rubber membrane filled with everyday materials, could help robots grasp objects as delicate as raw eggs or as heavy as steel girders.
"This smart material is one of the most innocent materials, a bunch of grains of sand, glass beads, or ground coffee beans," said Heinrich Jaeger, a scientist at the University of Chicago and a co-author, along with scientists from Cornell University and iRobot, of a new paper that appears today in in Proceedings of the National Academies of Sciences.
The new gripper holds objects through a combination of suction, friction and geometric interlocking. Say a robot wants wants to grab an egg. The gripper ball will extend, touch and wrap around a small part of the egg. Once the air is sucked out of the rubber ball the coffee grounds, sand, glass beads, or other granular material lock into each other and solidify around the object.