Discrete inventory control in systems with perishable goods - a time-delay system perspective

This study considers the problem of providing efficient control of periodic-review production-inventory systems with perishable goods. The stock storage and replenishment is modelled as a first-order process with delay subject to external perturbations. The study investigates formally the classical delay compensation mechanisms used in inventory control and shows deficiencies of inventory position and Smith predictor-based concepts in the context of systems with deteriorating stock. Then, a new dead-time compensation mechanism is developed and non-linear control law synthesised. The proposed control scheme is proved robust with respect to arbitrary demand and delay variations.