Design, modeling and first experimentation of a two-degree-of-freedom spherical actuator

This paper deals with the design of a two-actuated-degree-of-freedom (DOF) spherical electrical actuator for mobile robotic applications. It presents the different steps involved in this design, namely the choice of the actuation principle (induction), its application to the case of a spherical geometry and two DOFs, the analytical and numerical modeling of the motor, and the sizing and the manufacture of a first one-actuated-DOF spherical prototype. The first experimental results, obtained thanks to our test bench and presenting the torque vs rotor angular speed characteristic of the actuator, are likewise compared with the model predictions. (c) 2004 Elsevier Ltd. All rights reserved.