A loop material flow system design for automated guided vehicles

We develop an exact integer programming formulation to design a loop materi al flow system for unit-load automated guided vehicles. The model simultane ously determines both the design of the unidirectional loop flow pattern an d the location of the pickup and delivery stations. The objective is to min imize the total loaded-vehicle trip distances. To solve the problem, we con centrate on developing a better formulation for the LP subproblem, preproce ssing the problem, identifying the appropriate set of LP/IP routines, analy zing the mathematical properties of the problem, and developing an intellig ent branch and bound solution procedure.