General Purpose Hands for Bin-Picking Robots

Abstract

Bin-picking robots acquire a workpiece from a bin, reorient it, and place it into a machine. However, to achieve adaptability the system must incorporate general purpose hands capable of working with a wide variety of workpieces. To this end, eight guidelines for the design of general purpose hands for bin-picking robots have been identified on the basis of functional requirements. Using the eight guidelines as a framework, three hands were designed. The first design utilized a single vacuum cup which can sense contact, adapt to unknown surface angles, sense grip, and maintain a fixed hand-to-workpiece relationship. The second is a contour adapting vacuum gripper comprised of an array of 20 vacuum-gripping units which are capable of sensing discrete surface contour points while grasping. The third is a parallel jaw arrangement similar to those commonly found in industry, except that it has the capability of sensing overload and the presence of a workpiece within the hand. Each of the hands is described in terms of design features, control systems, and mode of operation. Advantages and disadvantages are indicated.