a Example 2.7 Analyzing the assignment of operators to multiple machines For the situation illustrated in Figure 2.18, it takes 0.5 minute to travel between machines, 1 minute to load a machine, 1 minute to unload a machine, 6 minutes of automatic machine time, and 0.5 minute to inspect and pack a finished part. As shown, the analysis begins with each machine empty and the operator standing in front of Machine 1 (M-1). The oper- ator loads M-1, walks to M-2, loads M-2, walks to M-3, loads M-3, walks to M-1, unloads M-1, loads M-1, inspects and packs the part removed from M-1, travels to M-2, and so forth. As shown in Figure 2.18, it takes 12 minutes for the operator and three machines to achieve a steady-state condition; thereafter, a repeating cycle of 9 minutes in duration occurs. (In other words, if nothing interrupts the activities of the operator and the three machines, the 9-minute cycle will repeat indefinitely.)