Configurable Grippers Have a Soft Touch
Think about Peeps, the marshmallow chicks found in Easter baskets. Did you know that they’re robotically handled? Clearly, the gripper on the robot has to be sufficiently capable of a light touch lest one of those chick’s heads get crushed.
Which brings us to the mGrip gripping system from Soft Robotics Inc. (softroboticsinc.com).
The gripping system uses a novel approach to solve the challenge of picking and placing relatively fragile items at speed without damaging them. How fragile? Soft Robotics cites a customer that makes plastic clips used in car seat assembly that are still hot and slightly soft from the injection mold.
The Soft Robotics system grippers are hollow, rubber-like fingers filled with compressed air. They contract around an object securely but gently, with give, less like a pair of pliers and more like a mother’s hand. The force calculations needed to pick and place without damaging a part are much less complex than with conventional hard tools. And the soft grippers can cycle at 3 – 4 times a second: The seat clip-maker uses the system with an ABB robot to maintain a production rate of a hundred parts per minute.
The customizable mGrip kit is available in two configurations. The circular version has the components needed to build a circular tool with either four or five fingers. It can be configured for geometries with a spacing range of 2.5 to 6.1 inches. The parallel kit enables building a parallel tool with either two, four or six fingers and can handle geometries with a spacing range of 1.5 to 4.7 inches.
While mGrip was designed particularly with collaborative robots in mind, it can work with—and keep up with the speed of—any industrial robot.