Research On Electro-hydraulic Eervo Loading Control System Of Electric Spindle Based On LabVIEW

As the key feature, the reliability level of Motorized spindle becomes the keyfactor in promoting the reliability level of CNC machine center. Improving thereliability of the key features is the key to promote the whole machine’s reliabilitylevel, and carrying out the functional unit reliability test is the important technicalways to improve the CNC machine tools’ reliability. Developing the motorizedspindle load test, simulating the actual stress state of motorized spindle, stimulatingthe potential failure of motorized spindle and obtaining the reliability data provide thebasis for reliability design and reliability growth of motorized spindle. Theelectro-hydraulic servo loading system can effectively simulate the actual stresscondition of motorized spindle based on the advantages of high control precision, fastresponse speed, big output power, easy to implement. Therefore, developing themotorized spindle electro-hydraulic servo loading control system has greatsignificance in engineering practices.In combination with science and technology department of Jilin provinceproject-“special industry base construction project”, this paper researches motorizedspindle reliability test bed. Through analyzing the stress of motorized spindle and theconstruction of motorized spindle reliability test bed, establish mathematical modelsof motorized spindle electro-hydraulic servo loading control system, put forward anew-style sliding mode variable structure controller, improve loading performance ofelectro-hydraulic servo loading system, exploit motorized spindle electro-hydraulicservo loading control system based on LabVIEW, and conduct loading test onmotorized spindle, result of the test indicates that the control system improves thestability and tracking of the loading force effectively. The main contents of this paperare as follows:1. Overall scheme of electro-hydraulic servo loading control system. Get overallscheme of electro-hydraulic servo loading control system, explain the hardwaremodels and enabled functions of the control system by analyzing the mechanicalstructure of motorized spindle reliability test bed and the soft hardware requirementsof control system.2. Electro-hydraulic servo loading system modeling. Through establishing the mathematical models of electro-hydraulic servo valve and flow continuity equationsof hydraulic cylinder, get the relationship between output force and control signal ofelectro-hydraulic servo loading system, then describe the system by using state-spacemethod, and discretize the system state-space equations.3. Sliding mode variable structure controller design. Confirm sliding modevariable structure control as control algorithm of electro-hydraulic servo loadingsystem, design sliding mode variable structure controller by using constant switchingcontrol strategy, and the switching function is state error vector quantity. Thensuppress the vibration and analyze stability of controller, optimize controllerparameters by using improved local optimum particle swarm optimization algorithm.4. Development and test analysis of electro-hydraulic servo loading controlsystem. Develop an electro-hydraulic servo loading control system based onLabVIEW, provide the construction, function and procedure code of system. Conductreliability loading test on motorized spindle, and verify the excellent controlperformance of the control system.The electro-hydraulic servo loading system based on LabVIEW researched inthis paper can carry on the stable load of motorized spindle and provide the vitaltechnical support to simulate the actual load condition for motorized spindle reliabilitytest.