The Research On The 3D Reconstruction Of Tool Wear Area

The 3D reconstruction of tool wear area is very important for the observation and the study of wear mechanism. For a long time, because of the limited method and its capability, as well as large cost of the 3D imaging machine, tool wear analysis has been largely limited to 2D parameters. Based on the study of the theories and key points of the Depth from Focus (DFF), a 3D reconstruction method of tool wear area has been designed. And a 3D visualization software of tool wear area was developed. The major research works are listed as follows:1. A 3D reconstruction method of tool wear area based on DFF was developed. Different focused pictures of tool wear area were taken from microscope. By using digital image processing, the depth information of the tool wear was taken and the tool wear's 3D topography was reconstructed.2. Double-threshold method has been introduced into the focus evaluate function. It is largely improved the correct rate of deleting noise points and background points, and improved the adaptation of operator.3. The 3D reconstruction's process has been analyzed, and a faster 3D reconstruction method was designed. Finally the 3D reconstruct test using this method proved it is faster than the previous method.4. In order to reach the automatic calibration, and to reduce the artificial error, a model of grating calibration was given. Calibration test result showed that the precision of the system was high enough. On this basis, some practicable 3D evaluation indexes of tool wear based on pixel was also given. After that, a tool wear measuring experiment was made.5. By using VC++ 6.0 and OpenGL, a tool wear area's 3D visualization software was developed. 3D data can be read into this software and then a 3D image of the tool wear data can be shown in the software's system.