Research On System Testing And Application Of Micro Nano CMM

With the development of modern manufacturing,the emergency of many micro-devices require the higher accuracy on the measuring machines.Therefore,it has become a research hotspot to study the coordinate measuring machine with nanometer measurement accuracy.The main research of this paper focus on the system testing and application research for the three-dimensional coordinate measuring instrument.Some issues still exist,like the poor stability of the coordinate measuring machine,the output signal coupling of the probe,the limitation of the measuring object and some uncorrected errors,etc.The research content is demonstrated as follows:1.In order to improve the frequency stability of the laser interferometer,eliminate the measurement error count and reduce the measurement interruption frequency,the laser device temperature is controlled by the PID module.The measurement system drift test and noise test,mechanical zero test,thermostat temperature control test,positioning error test,repeatability test of three-axis fixed point were completed.The result shows the repeatability of three-axis fixed point triggering is less than 20 nm,the temperature of the incubator was controlled within ±0.04 ?,and the positioning error of the worktable is less than 1 ?m with the movement stroke of 50 mm.2.According to the mechanical structure error of the three dimensional probe,the causes of the coupling between the output signals of the probes are analyzed.A probe calibration system is established,and the five directions of the probe are calibrated by the high-precision positioning worktable of the three-dimensional coordinate measuring machine.Finally,a four-order polynomial model was established based on different triggering directions to achieve the conversion between the table displacement and the probe output signals.The calculation results showed that the model error was within ±30 nm,and the probe calibration model was built based on Labview software.3.Through measuring gauge blocks,flat crystals,ring gauges and other standard workpieces,the testing function of three-dimensional coordinate measuring instrument is realized.And the coupling of XY laser interferometer and the separation of vertical error of the XY table are realized with the help of the standard parts.The measurement results show that the length measurement error of the gauge block is around 30 nm,and the roundness error of the ring gauge is diminished to 0.5 ?m after compensation.In addition,the geometric profile of the k9 plano-convex lens was also tested to achieve the goal of the three-dimensional profile measurement.