Energy Saving in Redundant Robotic Cells: Optimal Trajectory Planning

This work proposes a method to increase the energy efficiency of robotic cells by exploiting redundancy. The test case proposed for validation is a system typically used for fast pick and placements operations: a three degrees of freedom SCARA robot integrated with a separate linear unit moving the workpiece that provides an additional redundant degree of freedom. The design of the motion profile of the SCARA robot is based on splines interpolants defined by a sequence of via-points, while the motion of the auxiliary linear axis is described by a piecewise trajectory, so that both motions achieve acceleration continuity. The results show that a careful concurrent design of the trajectories of the robot and of the auxiliary axis can provide a significant reduction of the required energy.