Design of a transverse flux machine as joint drive for an articulated six-axis robot arm

This paper presents requirements on a articulated robot arm in service robotics and the derivation of requirements on a single joint of this arm. A modular concept with joint modules, each one realizing one axis of the robot arm connected by intermediate elements is proposed. Furthermore, the integration of a permanent magnet excited transverse flux machine as joint drive in this application is discussed. Transverse flux machines typically offer a high torque density at low speed. As torque demand increases from wrist to shoulder joint and speed demand decreases at the same time, this paper concentrates on the design of a shoulder joint module, where the integration of a transverse flux machine seems to be most promising. A design of a transverse flux machine as drive of an exemplary shoulder joint is proposed and results from a three dimensional finite element simulation are presented.