Synchronizing Schedules for Transportation

3. Single Machine Assembly Scheduling Problem

For the assembly scheduling problem, the assembly flow shop is first assumed to be a single machine. A release time is determined for each order to minimize the average waiting time (AWT) before transportation. AWT is defined as the mean of sum of the waiting times for all orders. Transportation allocation results provide the inputs for the assembly problem which includes the orders, quantity, and transportation departure times. Orders may be split and allocated to different flights. The split orders will be treated as separate orders in assembly.

The transportation departure time is taken as the due date of assembly for each order. The assembly schedules adhere to the following conditions: (i) each machine processes only one job at a time (ii) pre-emption is not allowed, which means once a job’s processing is started, it can not interrupted by another job and (iii) processing time of each order is known. Two methodologies for assembly scheduling problem are presented in this section.