Heuristic algorithm for tool requirements planning in flexible manufacturing system

Based on a tool movement flexible manufacturing system (FMS), the tool requirements planning problem was investigated, which determines the number of each tool type for a limited tool budget with the objective of minimizing makespan. The makespan and the tool wait delay were calculated through a recursive algorithm based on the insensitive effect of the tool transfer time on the makespan. Then the number of tool copies for critical tool types in the center tool storage, which has the maximal ratio of the effective wait delay to their total purchase costs in the critical machine, was increased. The above two steps were repeated until the tool budget was reached. Experiments were conducted based on the random data. The numerical results show that the heuristic algorithm proposed here has the better overall performance than others.