On the design of a seven-axis modular robot

This paper reviews the development of a modular robot architecture, and based on this architecture, it expands on the design of a seven-axis modular robot being developed at the University of Texas for prototype construction. Modularity is presented in terms of five granularity levels and the level which contains multi-axis-joints with removable actuators is selected as most suitable for the prototype. The manipulator contains three modules: a three-axis shoulder, a one-axis elbow and a three-axis wrist. Modular manipulator specifications that are derived from medium-scale, general-purpose maintenance tasks found, for example, in nuclear reactor maintenance or manufacturing applications are listed as design goals. These specifications are then used to define the arm kinematics, selection of the major components and structural design of the links and joints. Since the modular robot design tightly integrates mechanical elements with electronic components, it forms a good example to mechatronic system design