Computer aided production planning - SWZ system of order verification

Abstract

SWZ (System of order verification) is a computer implementation of the methodology that support fast decision making on the acceptability of a production order, which allows to determine not the best possible solution, but admissible solution that is possible to find in an acceptable time (feasible solution) and acceptable due to the existing constraints. The methodology uses the propagation of constraints techniques and reduced to test a sequence of arbitrarily selected conditions. Fulfilment of all the conditions (the conjunction) provides the ability to perform production orders. In the paper examples of the application of SWZ system comprising the steps of planning and control is presented. The obtained results allowing the determination of acceptable production flow in the system - determination of the manufacturing system parameters those that ensure execution of orders in time under the resource constraints. SWZ also allows to generate the dispatching rules as a sequence of processing operations for each production resource, performed periodically during the production flow in the system. Furthermore the example of SWZ and simulation system integration is shown. SWZ has been enhanced with a module generating files containing the script code of the system model using the internal language of simulation and visualization system.