A New Zero-Dimension Robot Wrist: Design and Accessibility Analysis

This paper presents the design of a robot wrist with zero hand length and unlimited mutually orthogonal joints. This design is an improvement over existing ones. When equipped with this type of wrist, a robot's entire reachable workspace becomes the dexterous workspace. Because some wrist joint limitations may need to be imposed under practical consideration, to better assess this new wrist design, kinematics on robot point accessibility is derived. An algorithm and a software package are developed that enable the plotting of the point accessibility throughout the robot's entire workspace. Examples for demonstration are also included.