Scheduling manufacturing systems

Three industrial scheduling problems arising in manufacturing systems are discussed. The first problem is the single machine scheduling problem with sequence-dependent setup times and precedence constraints. The mixed-integer formulation proposed is simple and easy to implement. The problem is solved with an efficient heuristic algorithm. The second problem is a machine cell scheduling problem. A new dispatching rule is developed to minimize the total tool setup time. The performance of the proposed rule was tested against three priority rules: first-in-first-out, shortest processing time, and longest processing time. The results of the simulation experiment showed that the dispatching rule performs better than the rules tested. The third problem is concerned with scheduling laser cutting operations. The overall objective is to minimize the number of overproduced parts and randomly nested parts. An integer programming formulation is proposed.