The Design And Test Of Computer Aided Tribology Measurement Method

Friction and wear testing machine is the most important test tool in tribologicalresearch. With the rapid development of modern automatic control and testingtechnology, the tribological test machine has put forward higher requirements in terms ofaccuracy control, real-time signal acquisition and processing system, need to exploitpowerful test system. At present, the domestic universal testing technology is by foreignmonopoly, develop quite slowly and the lack of research on technology and method oftesting and controlling, so there is much room for improvement. Supported by theNational Natural Science Foundation and the national973Plan, computer aided frictionapparatus based on graphic programming language LabVIEW to achieve the signalacquisition, synchronous display, background real-time data compression, solve the massdata storage problem; Research on control method of test automation testing machine; Atthe same time by redesign lubricant friction test device that can expel of friction heateffect, to explore the influence of oil temperature on the lubrication properties. The mainresults and conclusions of this paper are as follows:(1) Designed of a real time data acquisition testing system of pin-disc frictiontesting machine based on LabVIEW, successfully implementation of the user interfacecontrol, signal acquisition of pressure, torque and others, display real-time datacompression, friction coefficient calculation, and data storage function and so on.Through test and verification measurement system can effectively solve the mass datastorage problem of tribological test, improves the efficiency of the computer, and hasextensive adaptability on the tribological test data acquisition.(2) In order to improve the test ability of SKODA-SAVIN wear testing machine,designed the experimental process automatic control and data acquisition system basedon the LabVIEW, realized friction force and the temperature signal data acquisition,serial communication, the frequency converter, automatic speed control, the frictioncoefficient calculation, data storage and other functions to meet the special needs of testprocess.(3) To accurate evaluate the effects of temperature on the tribological properties oflubricating oil, redesigned the four ball test machine and its signal detection and dataacquisition system, experiments prove that the test machine can exclude the influence of environment temperature on the friction heat, and ensure measurement accuracy offriction and lubrication oil temperature of the test machine, meet the test needs.(4) Analyzed the relationship between the parameters and the test data collectionbased on the process of LabVIEW data acquisition, focus on the anal ysis of samplingrate and the number of mean value of data loss. The results show that: When thesampling rate is low, the time of data processing and data display is too slow, leading toeach cycle of read data is interrupted, so in the specified period, the output data isreduced; when the sampling rate is high, under the same conditions of the mean value,using very high sampling rate for long time will lead to not enough memory or diskstorage data is too slow, and this situation will cause a massive data loss.(5) By the experimental study of high temperature tribological performance of threekinds of ester lubricants by experiment, we discussed the influence of temperature on thecharacteristics of the boundary film lubricating oil, and try to use the friction coefficientmutation time to judge the desorption process of lubricating oil film, the results show:the friction coefficient increases sharply during the test process reflect the actual processof the removal of the lubrication oil film, and the temperature does not risecorresponding to the temperature of oil film completely desorption.