Manufacturing

Project for industry partner: Ramstar



A decision support system for production scheduling


A customized decision support system (DSS) has been developed for a small and medium-sized
enterprise (SME) manufacturer and vendor of inserts located in the southwest of Canada. The DSS is
capable of scheduling the jobs inputted while minimizing an objective.


The DSS has been implemented with Visual Basic for Applications (VBA) on the top of MS Excel. It
provides a user-friendly interface through Excel spreadsheets. The system guides the user to input job
orders information. The DSS has two solving methods: Classical dispatching rules and Hybrid Bacterial
Foraging Optimization Algorithm (HBFOA). Classical dispatching rules are comprised as follows: first-
come-first-serve, smallest processing time, earliest due date and minimum number of operations. The
HBFOA is a metaheuristic that is inspired in the behaviour of the E. Coli bacteria to seek for food. The
HBFOA has been improved by the hybridization of the simulated annealing metaheuristic. The user has
the choice to select any of these approaches to solve the scheduling problem. Similarly, the DSS is able
to handle two objectives separately. It can minimize makespan or weighted tardiness. Makespan is
defined as the maximum completion time of all the operations of all the jobs. Weighted tardiness is
described as the sum of the tardiness of each job multiply by its respective weight. This objective is
useful to take into account priorities or penalties of each job. In the same manner, the user chooses the
objective to be minimized.


After inputting all the required information, the DSS shows a set of schedules with detailed information
such as start date, shipping date, tardiness and due date. Finally, the user can plot a Gantt chart of the
solution required. In the same manner, the DSS can export the schedule to a new Excel workbook.

File Attachments: