Research On Calibration Method Of Angle Error And Size Error Of Industrial CT System

As a new nondestructive testing instrument, Industrial CT system can beused for detecting internal dimensions and features which can not be achieved byconventional instruments. However, due to its special imaging principle and complexerror sources, research on its calibration is still at the exploratory stage all over theworld, and there are still many problems to solve.In this dissertation, the traceability of Industrial CT system is studied deeply.And a new approach of CMM calibration during the traceability chain has been putforward. In addition, error sources including angle parameter, repeatability error,probe error and length measurement error have been discussed in detail. The majorcontent of this dissertation include:The importance of analysis and calibration of error source of Industrial CTsystem is discussed. After a review over the current method of calibration, researchcontents are determined and innovation points are introduced.Calibration of CMM in traceability steps of Industrial CT system has beenstudied. A measuring method of CMM coordinate measurement error based onself-calibration algorithm is proposed because it is difficult to achieve high precisioncalibration.The simulation and experiment results show that the precision can reachup to the order of submicron.A geometry model of mechanical structure of Industrial CT system has beenestablished. And angle parameters because of non-ideal geometry position betweendetector, rotary table and source have been studied. A method based on spatialanalytic on solving the angle parameters is proposed. Simulation and experimentresults show that the precision can be less than30degree seconds.The accuracy evaluation indicators of industrial CT system, includingrepeatability error, probe error and length measurement error have been studied.Combined with specifications and guidances, experiments on the Industrial CTsystem have been carried out. In addition, influences of parameters selecting on error measurement have been discussed.Summary of this dissertation has been demonstrated and some suggestions onthe further study are given at the end.Researches in this dissertation are innovative in the traceability chains,breakthrough in measurement of angle parameters, and exploratory in the calibrationof size error. And information in this dissertation will play a positive role on thespecifications establishment for the calibration of Industrial CT system.