A Spherical Self-Adaptive Gripper with shrinking of an elastic membrane

The traditional grippers with multiple fingers are able to grip a variety of objects. But the structure is complex, the control is complicated and the cost is high. A novel gripper, Spherical Self-Adaptive (SSA) Gripper was developed. The SSA Gripper is capable of gripping multiple objects self-adaptively. The SSA Gripper consists of a bowl part, an elastic membrane, water, a tendon and a two-segment aisle. In SSA Gripper, the motor pulls the tendon, and on the other end of the tendon, the elastic membrane which contains water is tightened and shrinks. In cooperation with the bowl part, some water enters aisles and the elastic membrane wraps the object self-adaptively. The water presses the object and there is a vacuum region between the elastic membrane and the object. Through the water pressure, atmospheric pressure and the friction between the elastic membrane and the object, the gripping process is achieved. The experiments show that the SSA Gripper can adapt to grip different shapes and sizes of objects in different directions automatically; the SSA Gripper can grip multiple objects simultaneously; simple structure, easy control and low cost lead to the potential for bulk productions and large-scale applications.