Integrated design of a 4-DOF high-speed pick-and-place parallel robot

This paper draws on robotic mechanisms theory and elastic dynamics to propose a new methodology for the integrated design of a 4-DOF SCARA pick-and-place parallel robot. The design process, which is readily applied to other designs, is implemented by four interactive steps: (1) conceptual design and mechanical realization of the light-weight yet rigid articulated travelling plate; (2) dimensional synthesis by minimizing the maximum driving toque of a single actuated joint; (3) structural parameter design for achieving good elastic dynamic behaviours; and (4) motor sizing necessary to generate the specified cycle time. Based upon the proposed process a virtual prototype is designed for achieving a cycle time for up to 150 picks/min.