Study on Development of an Operation Planning System Based on Case-Based Reasoning Using Machining Features

High-speed and high-precision machine tools developed recently have contributed to shorten machining time in parts machining. However, it consumes long time to determine operation parameters such as machining area, machining method, cutting tool and cutting conditions, and they deeply depend on operators' knowledge and experience. Thus, the preparation time before parts machining remains as a critical issue to be solved to achieve high-mix low-volume production. Therefore, in order to improve the efficiency of process planning, this study proposes an operation planning system to derive operation parameters based on case-based reasoning using recognized machining features. By using information of machining features, it becomes possible to widely deal with operation parameters such as not only cutting tool and cutting conditions, but also tool approaching and retracting patterns that are required to be input in CAM system. Additionally, since machining cases are added to a case database sequentially, the rules for case retrieval are automatically adjusted to utilize the past machining cases effectively in this system. From the result of a case study, it is confirmed that the developed system has a possibility to derive proper operation parameters in parts machining.