In this work we investigate the influence of motor axes orientation on the workspace volume of 3-DOF manipulators, showing that the Delta configuration is not optimal. The configuration characterized by $α=ArcTan1/2≈35.26°$—the inclination of each motor axis to the horizontal plane (for the Delta robot α=0°), and $β=60°$—the rotation of each motor with respect to the vertical axis (for the Delta robot β=0°), known as the New University of Western Australia Robot (NUWAR) is shown to be advantageous over the Delta configuration in terms of workspace volume and shape. These results led to the construction of a prototype and an Australian Patent application.

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