Energy Efficient Control of an Overhead Crane by Optimizing a Smooth Waveform Command Shaper

Enhancing the energy efficiency in controlling an overhead crane during repeated rest-to-rest movements can result in significant energy savings. Moreover, it influences both maintenance expenditures and safety. This study focuses on optimizing a smooth wave command shaping profile to reduce energy usage and enhance the motion efficiency of an overhead crane. A smooth single-mode command shaper is modified to reduce the energy required during the trolley maneuver. The nonlinear equation of motion for a simple crane is derived, linearized, and then solved to determine the optimal controller performance. An extra constant is added to a smooth waveform command shaper and then optimized to enhance the required energy. Furthermore, the selectable maneuvering time feature of the smooth command shaper is utilized to further enhance the maneuver's efficiency. The results obtained are compared with several well-known input/command shapers. The optimized command shaper profile can eliminate all residual vibrations induced and reduce energy consumption by 30% compared to the most effective unoptimized input shaper and 45% compared to the classical smooth command shaper. The performance of all shapers is numerically and experimentally validated on an experimental overhead crane.