A Batch Scheduling Model for a Three-Stage Flowshop with Batch Processor and Heterogeneous Job Processor to Minimize Total Actual Flowtime

This research deals with a three-stage flowshop, processing two types of products. In the first stage, two heterogeneous machines assemble electronic components, and in the second stage, two dedicated parallel machines assemble the assembled electronic components with other components to produce respective types of products, where both the stages constitute job processor machines. The third stage is a common machine of a batch processor to conduct a functional test. The objective is to minimize total actual flowtime, where the actual flowtime of a part is defined as the time interval between its starting time of processing and a common due date. The problem is formulated as a mathematical model, and a heuristic procedure consists of two algorithms to solve this problem is proposed. The first algorithm is used to determine production batch sizes and the batch production sequence, whereas the second algorithm is used to select the machine in the first stage. The proposed models and algorithms are built by integrating all processes that occur at each stage. An illustrative example is intended to show that the proposed algorithms could perform well.