A two-step dynamic scheduling and assignment method for tooling original design manufacturers

Tooling original design manufacturers have to meet highly customised product design requirements and provide a reliable delivery time for their buyers. For such mass customised tooling, high uncertainties and complexity are inevitable in the manufacturing process, especially in the labour-intensive final assembly department. We propose a two-step dynamic method that helps the tooling manufacturer in scheduling and assigning jobs at its assembling department. First, the algorithm creates a queue for incoming orders based on the bottleneck sector with a modified critical ratio (mCR). Second, the orders are assigned to assembling teams by the Hungarian method based on the availability and competitive advantage of each team. This method allows managers to update each operations team on-site, reduce the statistical dependency, and avoid work-in-process inventory build-up in the production system. In a numerical study, we illustrate the effectiveness and cost reduction potential of our method.