本论文在实验的基础上对立式加工中心铣削、钻削功率信号的特征进行了研究，提出了铣刀、钻头磨损、破损在线功率监控方法，研制了立式加工中心刀具状态在线监控仪。 该监控系统采用了“基于机床速度向量的加工状态识别技术”并针对立式加工中心的工作特点对其做了改进和扩充。在不与数控机床直接通讯的条件下能正确地识别机床加工状态的变化及典型刀具类型。在刀具监控技术上采用了多模型结构：针对铣削加工其切削参数变化复杂而又不易检测的特点采用了基于过程记忆的自学习方法进行监控；对于切削参数变化比较简单且易于检测的钻削过程，采用了基于过程辨识的刀具监控方法，对其中的GMDH算法做了改进，并将其运用于监控门限的生成。开发了通讯模块和工作站监控仪管理进程，使该系统能和上级工作站进行双向数据通讯，实现了监控仪在CIMS环境中的集成。 采用上述技术的监控仪经过了实验的验证，能够准确地识别铣刀、钻头的磨、破损。该监控仪做为CIMS实验工程配套技术的一部分通过了清华大学CIMS-ERC的课题验收与成果鉴定。

In this paper, research on the characteristics of spindle power in mill{rig and drillingprocess was carded out based on the experiments on a vertical machining center.Methods of monitoring tool wear and breakage in milling and drilling are presented. Anon-line tool failure monitoring system was developed for a vertical machining center. i he method of' working status recognition based on the machine speed vectors wasadopted and immproved in the momtorintg system according to the characterize of themachining center. The monitoring system can correctly recognize various machiningstatus and tool types without communication with the machine center. A multi-modelarchitecture was used in the tool failure monitoring: For the milling process in which thevariation of the cutting parameters were difficult to get, a machining process self-learning method was used. For the drilling process in which the variation of the cuttingparameters were easy to get, a method based on machining process recognition wasused. The Group Method of Data Handling (GMDH) was improved and was also usedin the generation of the monitoring thresholds. A commmcation software and a toolmonitor management sub-process on a workstafion were developed to send [hemonitoring data to and from the upgrade workstation so that the monitoring system wasintegrated in the CIMS enviroment. The monitoring system which use the techniques above was verified in theexperiments. It can successfully recognize the failure of the milling cutter and drill. Themonitoring system pass the final check by CIMS-ERC as a part of CIMS experimentengineering auxiliary, technique.