Scheduling operations on parallel machine tools

We introduce unique scheduling problems that arise for multiple spindle machine tools. The ability of these machines to perform simultaneous operations on more than one part creates constraints that are not found in the traditional scheduling literature. Two types of solution procedures are introduced for these problems. The first uses priority dispatching rules and a delay factor concept, while the second uses a genetic algorithm with a random keys encoding. The effectiveness of these methods is demonstrated on test problems with comparisons to lower bounds.