Design and realization of algorithms of quick searching boundary based on 3D cloud data

It is an important part to find boundary points and to fit the boundary edge quickly in surface reconstruction,when surface are reconstructed by using the cloud data for the original model.An algorithm of fast search boundary was proposed in the paper.Firstly,to find Kneighbors of all spatial data points,and divided area measured into eight parts,and to judge whether there are data points in two adjacent parts,to improve search accuracy.The calculation method of a cavity radius was introduced based on the experimental data,and design steps are described,the running results of the algorithm are also given,the results were compared and analyzed ones.The search algorithm for boundary points were improved by eight parts method combined with K nearest neighbor,making its accuracy better and computing time shorter than the original four parts.The experimental results demonstrate that the algorithm of boundary extraction has high precision,fast running speed,especially in the concave area,the original model profile can be described more accurately,and provided high quality data for the boundary fitting.