The role of the production scheduling system in rescheduling

The paper presents the rescheduling problem in the context of cooperation between production scheduling system (PSS) and other units in an integrated manufacturing environment - decision makers and software systems. The main aim is to discuss the PSS functionality for maximizing automation of the rescheduling process, reducing the response time and improving the quality of generated solutions. PSSs operate in the meeting of tactical and operational level of planning and control, and play an important role in the production preparation and control. On the basis of information about orders, technology and production system state (e.g. resources availability) they prepare and/or update a detailed plan of production flow - a schedule. All necessary data for scheduling and rescheduling are usually collected in other systems both from organizational and technical production preparation, e.g. ERP, PLM, MES, CAPP or others, as well as they are entered directly by the decision- makers/operators. Data acquired in this way are often incomplete and inconsistent. Therefore the existing rescheduling software works according to interactive method - rather support but does not replace the human decision maker in tasks planning. When rescheduling, due to the limited amount of time to make a decision this interaction is particularly important. An additional problem arises in data acquisition, in the process of data exchanging between systems or in the identification of new data sources and their processing. Different approaches to rescheduling were characterized, including those solutions, where all these operations are carried out by an autonomous system and those in which scheduling is performed only upon request from the outside, for the newly created scheduling data representing the current state of the production system.