Evaluation of the impact of information delays on flexible manufacturing systems performance in dynamic scheduling environments

The significance of the adverse effects of information delays (IDs) on flexible manufacturing system (FMS) performance is getting increasing attention from manufacturing systems managers, planners, schedulers, Enterprise Resource Planning software developers, and researchers because of their potential to disrupt production schedules. In this paper, we examine the extent of the adverse impact that IDs have on FMS performance. The FMSs are assumed to operate in a "review period" mode; i.e., the control decisions (e.g., sequencing and dispatching) are taken based on information monitored at predetermined intervals of time called "review periods". The performance deterioration occurs due to the obsolescence of system status information. Key empirical findings based on extensive simulation experiments are: (1) IDs significantly degrade FMS performance for due date-based measures (mean tardiness and percent of jobs tardy); (2) IDs also degrade FMS performance for non-due date-based measures (mean flowtime and average machine utilization), albeit to a less severe degree; (3) routing flexibility, often regarded as a significant factor to influence FMS performance, is superseded by status review information delay.