An efficient framework for job input sequencing and vehicle dispatching in a flexible manufacturing system based on AGV transport

This paper addresses the scheduling problem in automated job shop environments. We focus on the job input sequencing and vehicle dispatching problems in a flexible manufacturing systems using a single vehicle automated guided vehicle systems. A solution approach for a n/m/G/C_max problem is proposed. An iterative procedure is developed where, at the first stage a stochastic algorithm determines a job input sequence. At the second stage a discrete event simulation experiment is performed to investigate the system performance and the makespan depending on the job input sequencing and the vehicle and machine dispatching. The estimated makespan is then used by the stochastic algorithm to improve the initial job input sequence. The originality of our approach is to determine simultaneously the job input sequencing and vehicle dispatching taking into consideration the dynamic behaviour of the system as well as the finite input and output buffer capacities