SEQUENCE OF OPERATIONS OPTIMIZATION IN SINGLE-STAGE MULTIFUNCTIONAL SYSTEMS

The problem of optimizing a traditional or high-speed single-stage multifunctional numerically-controlled machine is investigated. In current practice, the parameters of the sequence for part machining processing, cutting conditions, and tool magazine organization are defined manually by a machine programmer or operator. These parameters are usually conservative and away from their optimal values. The machine should, however, maximize the throughput without cost penalty. In this paper, mathematical machining models combined with heuristic optimization algorithms (which determine the optimum values of the aforementioned parameters) are proposed to solve this problem. The optimum tool magazine organization for large batch or mass production systems minimizes the tool change time and maximizes the time between tool magazine reloadings. The optimization scheme can be utilized for modeling and simulation purposes in metal cutting environments where numerical control (NC) equipment or flexible manufacturing systems (FMSs) are used. This work is therefore directed toward the development of an expert-system-based automated part machining process planner and tool magazine organizer. Its goal is to reduce the use of skilled human interaction. The proposed approach and its advantages are finally illustrated through an application example.