Research On Self-calibration In Precision Measurement

With the increasing demands of precision measure technology in allfields，there has been growing attention on the development of precision positioningtechnology. The advance of precision positioning technology needs a standard withhigher precision used for calibration. But a standard with high-precision is tooexpensive or can not be manufactured in the level of current technology. Accordingto this situation, the technology of error separation has widely concerned. As a kindof error separation technique, self-calibration technique was studied in this paper,which separates systematical error in the measurement results by mathematicalalgorithm. Therefore, the precision accuracy of stage and measuring results can beimproved. The study of self-calibration includes theory model, software stimulation,experiment and application in this paper.Firstly, the source of error in measuring results has been analyzed andone-dimensional self-calibration technology model was established. Least squaremethod was used to obtain the optimum solution. In order to prove the validity andaccuracy of the algorithm, software stimulation was studied. The experiments havebeen carried out by image measuring instrument and second-class scale respectively.Secondly, two-dimensional self-calibration algorithm was put forward based onone-dimensional self-calibration technology. Combined with the noise, the influenceof noise on the results was studied. Grid plate was used to calibrate the positioningaccuracy of2-D stage for image measuring instrument.Then the limits of the parameters in the model were studied. In addition,different schemes have been proposed to test the influence on calibration technology,which laid a foundation for the problem of position numbers in the experiment.Finally, flatness evaluation based on self-calibration technology was developed,in which, the effect of random noise was studied.Researches in this paper are innovative compared with traditional calibrationmethod. These researches improve the positioning accuracy of stage provide acertain reference for precision measurement field.