Optimal manufacturing flow controllers: zero-inventory policies and control switching sets

A continuous-flow control model of a single workstation with multiple failure modes and part types is considered. Although the general model is intractable, properties of the optimal control policy are identified that can be used to help formulate heuristic policies. Control switching sets are described and shown to have a threshold form. For a single machine with two part-types, conditions are found under which no inventory is held, analogous to the single-part-type result of Bielecki and Kumar (1988)