中文摘要：

针对当前点云Snake模型研究中存在的问题，提出点云的气球力Snake模型．该模型将二维图像Snake中的气球力推广到三维点云中，用于设计点云Snake模型的外部能；按曲率将点云分为特征点和非特征点，特征点除包含目标轮廓线外，还包含噪声点．外部能根据轮廓点的类型采用不同的移动方式：当轮廓点为非特征点时，外部能会迫使该点向目标轮廓线移动，则即使初始轮廓线远离目标轮廓线，Snake模型也能正确收敛；当轮廓点为特征点时，外部能会使该点固定或在附近振荡，可利用该方式分离噪声点与非噪声点，达到剔除噪声的目的．实验结果表明，文中模型能有效地解决Snake模型对初始轮廓线位置敏感以及易受噪声影响的问题．

英文摘要：

In order to solve the existing problems in current researches on the Snake models of point cloud, a Snake model of point cloud using balloon force is put forward. In this model, the balloon force is extended from 2D image to 3D point cloud to design external energy. The model classifies point cloud into feature points and non-feature points according to curvature. Besides target contour, noises are contained in feature points. The external energy has different motion patterns to different point patterns： On one hand, the external force energy will force the contour point to move to the target contour if it is not a feature point. Snake can converge correctly even if the initial contour is far away from the target contour. On the other hand, the external force energy will make the contour point fixed or oscillate if it is a feature point. When the contour point is a noise, the motion of neighbor non- feature points will force it move off the noise region, this means noises can be removed in the model. Experiments show that the proposed model is insensitive to the position of initial contour and can be less affected by noise points.