Simulation and Analysis of Production Scheduling in Eyeglasses Industry for Productivity Improvement

Abstract

Manufacturing systems have become progressively complex and costly. Competition and the drive for profits are forcing companies to improve productivity in their production lines through effective and proper methods of evaluating production schedules. Computer simulation is one of the reliable and well-established methods that enables companies to evaluate their line scheduling. It helps manufacturers detect and rectify the line problems and move forward with productivity improvements. The main contribution of this paper is threefold. First, it defines a computer-based framework for modeling and simulation of production schedule using real-world data collected in an eyeglasses production factory. Second, it investigates an experimental conformance verification, i.e., confirming whether the simulation carried out in the production line conforms to its intended specification or not. Therefore, the simulation results are verified by the experimental results obtained from the line. Based on the confirmed simulation study, the Generating station and Washing station are considered the line’s bottlenecks. Third, it proposes some suggestions by introducing and using “what-if” analysis. Creating “What-If” scenarios is extremely beneficial for manufacturers as it allows them to conduct simulation runs based on demand forecasts and constraint modeling for generating various iterations of the production schedule. Here, different scenarios are compared and the most advantageous one is chosen. In this study, increasing 4 machines in the Generating station and 6 workers in the washing station propels the company to achieve higher system utilization and increased throughput rates by 25% and 46%, respectively.