Adopting a circular open-field layout in designing flexible manufacturing systems

Abstract

A new circular open field layout composed of a vehicle-based material handling system and multiple circular loops is proposed. The suggested layout offers more flexibility for high-mix low-volume production systems compared to other layouts as it maximizes the number of equidistant machines. A novel approach that integrates experimental design with computational modelling and statistical analysis was followed to study the proposed system. Forty experimental scenarios were generated using Face Centred Composite Design (FCCD) to numerically investigate the effect of layout, production quantity, variety and complexity on minimum production cost. To determine the minimum production cost in each experiment, a linear programming (LP) optimization model was formulated with layout dependent machine distance algorithm. The model solves for the optimum location of the machines and machine cell formations that minimizes the production cost. It considers material handling costs, alternative process routing, operations sequence, lot splitting, and machine costs. Furthermore, the cost was modeled using regression analysis to provide a quick estimate without the need to run computational intensive numerical models. Results reveal the effectiveness of the proposed layout with cost savings reaching 35% compared to traditional open field layout when product variety and complexity are increased.