Increasing position accuracy and energy efficiency of servo-actuated mechanisms

This paper quantitatively reports about a practical method to improve both position accuracy and energy efficiency of Servo-Actuated Mechanisms (SAMs) for automated machinery. The method, which is readily applicable on existing systems, is based on the 'smart programming' of the actuator trajectory, which is optimized in order to lower the electric energy consumption, whenever possible, and to improve position accuracy along those portions of the motion law which are process relevant. Both energy demand and tracking precision are computed by means of a virtual prototype of the system. The optimization problem is tackled via a traditional Sequential-Quadratic-Programming algorithm, that varies the position of a series of virtual points subsequently interpolated by means of cubic splines. The optimal trajectory is then implemented on a physical prototype for validation purposes. Experimental data confirm the practical viability of the proposed methodology.