Conflict‐free tow train routing in just‐in‐time assembly lines

Abstract Conflicts among tow trains pose a significant challenge in just‐in‐time manufacturing systems, impacting both safety and efficiency. This paper proposes an innovative solution to achieve conflict‐free tow train routing. In our approach, the production layout is partitioned into “pixels.” The A‐star (A*) algorithm is then employed on this pixel‐based layout to create a distance matrix between workstations. Subsequently, a simulated annealing heuristic optimizes tow train routes to deliver parts demanded at the workstations. Additionally, a conflict detection algorithm identifies collisions among tow trains on the pixel layout, which are then resolved through two distinct conflict avoidance strategies. The algorithms are implemented and tested on a set of benchmark instances, demonstrating their effectiveness.