Performance of coupled closed-loop workstation capacity controls in a multi-workstation production system

In this paper, a dynamic model is developed for multi-workstation production systems in which closed-loop capacity controls for regulating WIP in individual workstations are coupled by adding predictive control, making capacity adjustments a combination of compensation for local disturbances and anticipation of downstream effects of capacity adjustments made upstream in the system. The added coupling at the control level combined with intrinsic coupling at the order-flow level effectively integrates planning and control, but increases system complexity. Control-theoretic methods are used to make dynamic analysis tractable and improve understanding of dynamic behaviour, which is illustrated using data from an industrial production system.