Analysis and design of robotic manipulators with multiple interchangeable wrists

The concept of multiple interchangeable wrist mechanisms is introduced as a cost-effective, practical method to improve the flexibility of a robot system without increasing the complexity of the wrist design. The interchangeable wrist concept is a natural extension of interchangeable tooling. The feasibility of the proposed concept for real-time applications is demonstrated by an analytical framework that incorporates the wrist-exchange procedure in the robot control hierarchy for the case of manipulators with interchangeable spherical and nonspherical wrists. An algorithmic approach that utilizes the individual kinematic properties of the arm and the wrists is then developed to generate an efficient solution to the kinematic control problem of the coupled system. The accuracy and computational efficiency of the proposed algorithm are shown through a numerical example for the PUMA 560 robot