A Unified PSO-based method for scheduling of multi-hoists in advanced Galvanic plants

In this work, we propose a method based onthe unified particle swarm optimization (UPSO) for no-waitmulti-hoist scheduling, including a collision avoidance heuristic.Conflicts due to track sharing between hoists and no-wait con-straints represent major issues to be addressed. Consequently,a complex optimization problem has to be solved dynamically,to identify the best operating strategy to be executed dependingon the characteristics of the current job list. A decompositionprocedure has been developed to speed up the solution ofthe large-scale optimization problem at hand. The proposedapproach is demonstrated on a real galvanic process layout,showing the improved performances achieved by the proposedheuristic compared to the monolithic approach.