System reliability and congestion in a material handling system

Congestion in a transportation system prevents vehicles from traveling freely. Therefore, congestion in a material handling system can reduce the systemʹs performance. This paper: (1) develops an analytical methodology for measuring congestion in a material handling system, (2) develops a congestion measure that is measurable in real-time and readily incorporated into existing analytical models for material handling system design and (3) develops quantitative relationships between critical material handling system variables and system congestion.