New adaptive gripper from Festo can pick up any shape
Gripping workpieces just as a chameleon's tongue grips insects is the operating principle of the new DHEF adaptive shape gripper from Festo. This unusual gripper can pick up, gather and set back down differently shaped objects without the need for manual adjustment, opening up new possibilities in automated handling, medical prosthetics and human-robot collaboration.
The DHEF gripper has an elastic silicone membrane that is flexible and pliable. It simply requires a standardised robot interface with integrated air connections and a supply of compressed air to be ready for use as a practical automation component. The standard sensor slot for position sensing and a bayonet lock for easy replacement of the cap are additional useful features.
The silicone cap of the DHEF adaptive shape gripper can fold itself over and grip objects of virtually any shape. This creates a firm, form-fitting hold. The elastic silicone enables the gripper to precisely adapt to a wide range of geometries. When combined with a pneumatic drive, the DHEF requires little energy for a secure grip.
Unlike mechanical grippers that can only grip specific components, the DHEF is extremely flexible. It can even manage components with freely formed shapes and round geometries. The absence of sharp edges makes it ideal for gripping sensitive objects such as air nozzles or trim strips. In principle, the gripper can pick up several parts in one movement: for example nuts from a bowl.
In combination, these features mean that the DHEF gripper can be used to handle small parts in classic machine building, in the electronic or automotive industry, in supply units for packaging installations, for human-robot interaction during assembly tasks or for prosthetic extensions in medical technology.
Getting to grips with nature
The DHEF’s innovative design was originally inspired by observing the natural world: in this case, a chameleon. The unique combination of force and changeable form of a chameleon's tongue can be observed when it is on the hunt for insects. Once the chameleon has its prey in its sights, its tongue shoots out like a rubber band. Just before the tip of the tongue reaches the insect, it retracts in the middle whilst the edges continue to move forwards. This allows the tongue to adapt to the shape and size of the prey and firmly enclose it. The prey sticks to the tongue and is pulled in as though caught on a fishing line.
The Festo Bionic Learning Network and researchers from the University of Oslo used these observations when developing a prototype with the name "FlexShapeGripper". The original concept has moved from a bionic prototype to a commercially available Festo product thanks largely to development work by two female engineers: Stefanie Seiler and Nenja Rieskamp.