Design Of An Optoelectronic Level And Its Application For Flatness Error Measurement

The level is a kind of precision instrument for measuring micro-angle,which is widely used in the measurement of horizontal angle,straightness and parallelism measurement of guide,flatness measurement of parts,and installation and adjustment of equipment such as precision machine tools,and coordinate measuring machines.With the development of automation and electronic measurement technology,the level has evolved from the traditional low-precision bubble method to the electronic method with high-precision and high-resolution,and can provide more reliable measurement for high-precision angular measurement in the mechanical manufacturing field.However,most of the level currently used can only measure one-dimensional angles,and it is difficult to measure the yaw angle and roll angle in the plane at the same time.Based on the principle of collimation,light refraction and reflection,a two-dimensional optoelectronic level with simple optical path structure was designed,which has characteristics of high-precision,low-cost and small-size.By using a polarization beam splitter and a right-angle mirror,the laser beam deflects 90° and the light intensity loss is minimized.Reliable fixtures were designed for optical components,and a two-dimensional angle adjustment module in flexible hinge type was designed to adjust the optical path with characteristics of high angle locking performance and high adjustment resolution.In order to reduce the structural deformation,the frame-type integrated shell structure was selected.In addition,based on LabVIEW graphical programming software,the Butterworth filter algorithm was used to remove the interference noise signal and promote the signal-to-noise ratio of the system,which greatly improved the level's measurement stability.Relevant performance tests of the two-dimensional angle measuring optoelectronic level were carried out such as accuracy calibration stability experiment and measurement repeatability experiment.The experimental results showed that the calibration error were ±0.6 ?? and ±0.5 ?? of X and Y directions respectively within the calibration range of ±100 ??.The drifts were 0.5 ??/h and 0.3 ??/h of X and Y directions separately.The measuring repeatability error was less than 0.4 ??.Finally,the two-dimensional angle measuring optoelectronic level was applied in flatness error measurement.Compared with one-dimensional angle measuring method in the national standard,the new two-dimensional angle measuring optoelectronic level method can greatly reduce the measurements time,and improve the measurement efficiency,especially in the planeness error measurement of medium and large planes.