ABSTRACT
Configuration is a fundamental classification for industrial robots. Configuration refers to the geometry of the
robot manipulator, i.e., the manner in which the links of the manipulator are connected at each joint. The
Robotic Industries Association (RIA, see https://www.roboticsonline.com/) defines a robot as ‘‘a manipulator
designed to move material, parts, tools, or specialized devices, through variable programmed motions for the
performance of a variety of tasks.’’ With this definition, attention here is focused on industrial manipulator
arms, typically mounted on a fixed pedestal or base. Mobile robots and hard automation (e.g., computer
numerical control [CNC] machines) are excluded. The emphasis here is on serial-chain manipulator arms,
which consist of a serial chain of linkages, where each link is connected to exactly two other links, with the
exception of the first and last, which are connected to only one other link. Additionally, the focus is on the first
three links, called the major linkages, with only a brief mention of the last three links, or wrist joints, also
called the minor linkages.