Method To Improve The Laser Tracking Measuring Accuracy For Large-scale Parts

The in-site measuring system with laser tracker for mega gear is aiming fordesigning a more capable measuring system by method the laser tracker and thecoordinate measuring machine. In the measuring system, the laser tracker is aimingfor establishing the position relationship between CMM and the measured piece.Measuring accuracy of the laser tracker system is very important to establish theposition relationship in the measuring system. In this thesis, first we study themulti-position of laser tracker and establish the corresponding mathematical model.Then we design a location method based on mega gear by multi-position model oflaser tracker. Finally, we design some experiments for measurement method ofmulti-position of laser tracker by different laser tracker equipment.Mega-gear positioning method based on Laser tracker Multi-station wasdeveloped to improve the accuracy of Mega-gear Measuring System composited ofLaser Tracker, and can ensure accurately the positional and attitude relation betweenmeasuring instrument and gear. The Redundant Data provided by Laser trackerMulti-station Measurement can be used to solve optimally equation of between twopoints. Multi-station measurements based on In-sit Mega-gear Measuring Systemwas carried out, and method of using Singular value Decomposition to correctconditional number of Multi-station measurement model analytical matrix wasanalyzed. Results of experiment showed that standard deviation of usingMulti-station measurement mode is much less than standard deviation of directlymeasurement at different stations. If directly measurement at different stations,standard deviations mean is0.024mm. By contrast, standard deviations mean is0.008mm using Multi-station measurement model. Therefore Multi-stationmeasurement model can have well high control precision. These research findingsprovide reliable data for the in-site measuring system with laser tracker for megagear. This measurement method not only can apply to in-site measuring system withlaser tracker for mega gear, but can apply to others laser tracker equipment.