Abstract: Aiming at scattered data， a set of equally spaced cutting face in vertical direction of maximum bounding box was used to segment scattered point cloud， and the method of cavity three-dimensional model was proposed by taking cavity three-dimensional laser scanning system to obtain original data as the basis. The direction and pitch of parallel cutting surface was determined firstly to divide and cut scattered point cloud. Then the location of scattered point cloud which is in cutting surface was determined by the minimum distance method. Finally， scattered points were sorted through convex hull the minimum distance method， and it was modeled after becoming ordered points. Applications show scattered points modeling algorithm of complex cavity is accurate， which can be realized in complicated scattered point cloud modeling.

Key words: complex cavity, scattered points, hatch, triangulation, convex hull algorithm