Production orders planning using additional backward pass scheduling approach

The paper focuses on the scheduling problem of minimizing flow time of production orders in job shop class systems. The proposed method supports both forward and backward scheduling and use additional backward pass for calculating the latest possible release date of a given production order. Depending on the adopted strategy, two or three stages are implemented in which the new due date and new release date is searched successively for each production order. Application of this approach causes that the scheduling of any order can be realized according to one of five ways. Four decision steps associated with the choice of the right method of order scheduling were distinguished. Examples illustrating the application of the proposed approach for the case of the forward and backward base strategy were also presented.