This Method of Robotic Pickup Could Stick

The sticky effect seen when you rub a balloon on your hair could be used to help robots pick things up, greatly expanding what machines can do in factories.

Grabit, a spinoff of SRI International, has developed a simple and cheap robotic hand that makes use of electrostatic attraction. Grabit’s robot hand, which was demonstrated at the RoboBusiness conference in Boston last week, is a little more complex than the balloon trick: for example, it uses powered electrodes to sustain the electrostatic attraction, and alternating polarities to avoid charge buildup and keep the device from collecting dust.

The new hand is part of a broader trend toward cheap, versatile robotic grippers (see “A Blob for a Robot Hand”). This new generation of graspers could expand the use of robots and let them collaborate more closely with humans (see “How Human-Robot Teamwork Will Upend Manufacturing”).

Electrostatic attraction is already used in some areas of manufacturing—for example, to hold microchip wafers in place. But the trick works best with clean, flat, smooth surfaces because the strength of the static cling depends on the size of the contact area. Electrostatic attraction is not suited to manipulating ultrathin sheets of semiconductor material, for example, because these sheets are often curved. And it’s not ideal for picking up irregularly shaped items.

Grabit’s gripper, however, uses flexible materials that have the same electrostatic properties. Part of the company’s innovation was developing materials that can conform to an object but still stand up to the wear and tear of factory use, says company CTO Harsha Prahlad.

The flexible surface of the grabber lets it support more weight and distribute the gripping force more evenly than conventional robots that use suction to pick things up. This improvement could allow robots to take on new manufacturing tasks, including jobs that involve handling delicate materials such as thin semiconductors for new, advanced solar cells. But the technology also offers a cheap way to pick up just about anything—fabric, bags of chips, 50-pound boxes of paper, single pieces of paper, mobile phones.

Grabit, which was founded in 2011, counts Nike and Samsung among its strategic investors.