A soft adaptive gripper for extremely small or flexible objects

Recent developments in soft grippers have shown promise in manipulating a wide variety of objects through utilization of various gripping mechanisms, such as granular jamming and multi-fingered grippers. However, manipulation of small bodies or extremely flexible sheets, such as pins, porous fabrics, and biological membranes, remains difficult. Here we present a soft, pneumatically-actuated gripper that exploits the buckling effect of an elastic membrane to either engulf sub-millimetric objects or pinch and separate flexible sheets from a stack. Our gripper is also able to lift thin sheets, whether artificial or biological, using their edges without causing folds or creases. We further show that important information for dexterous manipulation, such as success or failure of grasping and the dimensions and the material properties of the target object, can be detected by embedded soft capacitive sensors. Models for the gripping and the sensing principles are suggested and potential applications in manufacturing and medicine are explored.