Three-dimensional Stress Wave Imaging Method Of Wood Internal Defects

With the development of domestic and foreign scientific technology, more and more attention have been paid on stress wave NDT(Non-Destructive Testing) technology from both forestry industry and research fields. In this paper, three-dimensional stress wave based on timber and wood interior Tkriging and TIDW defect imaging algorithm for a more in-depth study. The main research results are given as follows:1. TIDW interpolation theory the concept of introducing non-destructive testing of timber dimensional visualization. TIDW optimized structural relationship between interpolation point and reference point in space, increased the search radius. Top-k query method was introduced to find the k value with relevant points and calculated value of the estimated point and three-dimensional imaging.2. TKriging spatial interpolation theory the concept of introducing timber destructive testing three-dimensional visualization. Kriging spatial interpolation method is to obtain the weighting factor sets according to the set of estimates points and the set of reference points in mathematical models. Top-k query method was introduced to find the k value with relevant points and calculated value of the estimated point and three-dimensional imaging.3. The original data were collected by woodworking portable of independent research from laboratory, and the tomography reconstruction algorithm was implemented on MATLAB platform to verify the feasibility of the presented algorithms. The experimental samples included six different types sample of defects and several experiments were test. Comparing and comprehensive analysis algorithm imaging and sample data, the results show that compared with the IDW and Kriging algorithm, the TIDW algorithm and TKriging algorithm have higher imaging precision, and can accurately reflect the characteristics of wood internal defects with a strong sense of realism.