Time windows and constraint programming to deal with strong restriction in the due date of productive systems

The APS (Advanced Planning and Scheduling) systems are widely used by companies; however, the traditional APS systems cannot deal with problems whose the due date is a strong restriction. The problem derives from the way companies use their scheduling heuristics. This paper addresses this problem by using the concept of time windows with the constraint programming mechanism. A procedure is shown to generate the time windows and how they can be used for the APS systems. The APS heuristic approach that uses the concepts of time windows with constraint programming is introduced to solve problems for which the due date is a strong restriction. These heuristics, with tasks allocation either at the beginning or at the end of the task time window, eliminate the need for a priority scheme. To illustrate the advantage of the proposal, some examples are presented.