Application of tabu search to process plan optimization for four-axis CNC turning centres

This paper describes our adaptation of the tabu search methodology to solve the process plan optimization problem for four-axis CNC turning centres. O ptimization of a process plan (specifically, the allocation of operations t o spindles and turrets) to minimize the cycle time for machining a workpiec e is not a trivial problem. This is due to the highly combinatorial nature of the problem that arises from the presence of dual spindles and dual turr ets and the machine's ability to perform operations in parallel machining a nd simultaneous machining modes. Our experiments to date have shown that th e tabu search based approach can be very effective in process plan optimiza tion, and is well suited for incorporation in CAD/CAM systems for four-axis CNC turning centres.