Scheduling heuristic resourced-based on task time windows for APS (Advanced planning and scheduling) Systems

Abstract

APS Systems (Advanced planning and scheduling) can provide production plans that enable a detailed analysis on the impact and possibility of analyzing different scenarios for a plant. The present work proposes an allocation heuristics of the type used in resource-based (bottleneck) APS Systems and uses task time windows in situations where product delivery time is important. The heuristics uses loading information from the equipment to dynamically assign (at each step) the equipment and the bottleneck time interval. Based on this information, it allocates the lots assigned to this equipment in the manner with the lowest influence on the bottleneck, so as to reduce its importance in the bottleneck problem without increasing its gravity. This heuristics enables successive and correct handling of all existing bottlenecks by updating the information at each step via constrained propagation mechanisms. The problem addressed is the scheduling of production in lot plants. Short-term problems with constraints on shared intermediate product storage resources (equipment) and plant operation in on-demand mode are considered.