Research On Integrated Scheduling Algorithm Based On Equipment Compact Operations

As traditional job shop scheduling algorithm uses workpiece as unit and the problem resolved is pure processing and pure assembling, these methods adapts to resolve product scheduling problem of single type and big batch. Along with the advancement and development of society, people pursuit advancement diversity, what is to say is to produce product of multi-type and small batch. At this time if traditional scheduling algorithm is still used, it will cause the hardness for assigning human resources and machine resources, further total working hours will be increased, and the production efficiency will be reduced, the traditional algorithm will lose its advantage. So researching multi-type and small batch product, namely integrated scheduling problem of complex product will has more theoretical value and practical meaning.Integrated scheduling of complex mult-product uses product as unit, and processing and assembling are processed simultaneously to increase the production efficiency. The existing integrated scheduling algorithm of complex product schedule product by procedures sequence strictly, namely schedule child nodes firstly, then schedule father nodes, it is the relationship of many-to-one. If schedule father nodes firstly and then schedule its child nodes, the relationship is one-to-many. So this paper proposes reversal sequence dynamic critical path integrated scheduling algorithm based on procedures and machine compacting. This algorithm combines integrated scheduling with reversal sequence, takes advantage of procedure compacting method to shorten idle time of machine when it takes fully account of the effect on total working hours by long path.As existing integrated scheduling algorithm of complex product just consider the product which needs to schedule currently and new products which arrive when scheduling, but ignore the situation that the start time of each product and deadline are all known. Aiming at this problem, this paper presents integrated scheduling algorithm based on delivery-criticality. This algorithm determines scheduling sequence of product by the time urgent degree and uses long path and short-time strategy to increase the parallel process degree among procedures. Theoretical analysis and examples show that this algorithm can give more reasonable integrated scheduling plan of multi-type and small batch complex product with different start time and deadline.At last, aiming at the situation that different product will scramble for resources in parallel period, this paper propose integrated scheduling algorithm which determines product scheduling sequence according to deadline from early to late. This algorithm combines layer priority, long path, short-time strategy and the advantage of procedures compacting method, and example validate the advantage of this algorithm.