Condition Monitoring And Fault Warning For Disc-type Tool Changer In The Reliability Bench Test Based On LabVIEW

As one of the key parts of a CNC machine tools,the disc-type tool change affects the reliability level of the whole machine directly.The research on the condition monitoring and fault warning of the disc-type tool change in the reliability bench test is an important research topic of the reliability of CNC machine tools,which is beneficial to grasp the trend of the state,formulate a reasonable maintenance policy,and improve its reliability.Therefore,this paper takes a domestic disc-type tool change as the research object.Combined with the reliability test system of the disc-type tool changer in the laboratory,the analysis of the main fault-pattern of a disc-type tool change,the design scheme of condition monitoring system,features of virtual instrument and Lab VIEW,a condition monitoring system for the disc-type tool changer is developed with the related hardware.In this paper,the method of signal denoising and the alarm for the fault of the locked rotor is developed.Meanwhile,the fault of the manipulator transposition is taken as the typical research object,and the method of SVR and GA is used to realize the fault warning.Three sets of experiments are carried out in this paper,which shows the feasibility of the methods.The main content of this paper are as follows.1.Condition monitoring system of disc-type tool change based on NI Compact RIO.The main fault-pattern of disc-type tool change is determined with the method of FTA and the statistical analysis of the field reliability test data for the CNC machine tools,which is the basis of the framework of condition monitoring system.In this paper,the principles and methods for the installation position of the sensors is presented,and then,these sensors are arranged on the reliability test system of the disc-type tool change.The hardware system for condition monitoring of the disc-type tool change is developed with NI c RIO-9035,C Series modules and the sensors,the parameters and functions of the sensors and the hardware of the system selected in this paper are given in detail.2.Design and implementation of the software system.With the introduce of the basic concept and main features of virtual instrument and Lab VIEW,this paper selects the Lab VIEW software for developing the software platform of condition monitoring system of disc-type tool change,realizes the data transfer among the FPGA,RT and Windows,the display,storage and fault alarm.And its structures,functions,and operations are given in detail in this paper.3.Research on the methods for fault warning of disc-type tool change.Due to the actual time domain signals is inevitably interfered by disc-type tool change itself and outside environment,which caused noise signals and the singular points,therefor,a new signal processing method based on improved Neighbor Block is proposed to improve the accuracy of the fault warning.Based on the analysis of the stator current and the fault of the motor,the starting current and the locked rotor current can be effectively distinguished by establishing the change trend of the current energy,which can realize the fault alarm for the locked rotor.In the methods of fault warning for the deviation of the manipulator,vibration mechanism is studied,for the shock vibration is mainly existed among the tool changing process,the time domain feature of the signal can response the state in the process of the tool changing obviously,therefore the time domain feature is taken as the analysis object.In this paper,the fault of the manipulator transposition is taken as the typical research object,the model of the manipulator's deviation is established based on the SVR,and then GA is used to optimize the regression error penalty factor and kernel width parameter.4.Experiments and data analysis.Based on the condition monitoring system of disc-type tool change,three sets of experiments are carried out in this paper,which showed the feasibility of the methods proposed or applied in the signal denoising,the fault alarm of the motor block and the fault warning for the deviation of the manipulator.