Study On The Method Of Regenerating NC Codes From Industrial CT Images

Industrial CT machine can get the entire data of one part without damaging it and save the data in bit images .It is the focus point of current Reverse Engineering that how to re-manufacture the part from the industrial CT slice images. However, the industrial CT images can't be directly recognized by NC machine not even manufacturing it.To the question, the methods of getting contour data from images and then turning it into NC codes are researched in this paper. At the same time, responding software is developed.Such is the main content:First, the method of extracting contour data from industrial CT slice images is researched. The contour data is extracted by filtering noise of images, threshold segmentation and contour extracting. During the image processing, the noise is filtered by using median value filtering mean. The threshold of image segmentation is confirmed by using iterative calculating method or experience by the statistic information of image histogram. The contour data is output by using multi-contour tracing method. Most of all, the multi-contour tracing method is researched as an emphasis of this paper. The experience shows that the contour data can be entirely output by using this method.Second, it is researched how to reduce and intercept the contour data. The contour data, which is in the same slice , is reduced by using the angle and chord method. The linear interception method is used between slices.Then, the processed data is directly turned into 2.5-axis contour milling NC codes after analyzing the format of ISO NC code and choosing some important parameters. The 2.5-axis contour milling tool path is simulated in the MasterCAM software.Last, the Z-Map mass point model is researched. According to the theory of Z-Map model, the contour data is re-constructed in new sequence forming 3-axis parallel milling tool path. The analysis shows that the parallel milling method can move more material from stock, and it is also simulated and verified in the MasterCAM software.