An Approximate Dynamic Programming Approach for Job Releasing and Sequencing in a Reentrant Manufacturing Line

This paper presents the application of an approximate dynamic programming (ADP) algorithm to the problem of job releasing and sequencing of a benchmark reentrant manufacturing line (RML). The ADP approach is based on the SARSA(lambda) algorithm with linear approximation structures that are tuned through a gradient-descent approach. The optimization is performed according to a discounted cost criterion that seeks both the minimization of inventory costs and the maximization of throughput. Simulation experiments are performed by using different approximation architectures to compare the performance of optimal strategies against policies obtained with ADP. Results from these experiments showed a statistical match in performance between the optimal and the approximated policies obtained through ADP. Such results also suggest that the applicability of the ADP algorithm presented in this paper may be a promising approach for larger RML systems