Current of the linear motor-based condition monitoring in milling

In recent years, a number of machine tools have been built using linear motors. These machine tools have great potential for precision and high speed machining. Nevertheless, a number of problems remain unsolved, such as monitoring and control. This paper presents a new tool breakage monitoring method for this type of machine tool by using the current of the linear motor. From a mathematical point of view, the new method uses a nonlinear energy operator to capture the abrupt changes of the motor current signal, which is directly related to the tool breakage. Experimental validation is included.