Time：9:30AM, December 30th  
    Place：F310, School of Mechanical Engineering
    Speaker：Professor Tang kai
    Host：Pro.Zhu Limin

    Abstract
    Five-axis sweep scanning is an emerging technology for fast data point acquisition for freeform surfaces. However, currently sweep scanning paths still mostly reply on manual determination. This paper presents a novel strategy to automatically plan a sweep scan path for an arbitrary free-form surface, which takes full consideration of the characteristics of the 5-axis inspection machine. Our approach is inspired by observations on determining the sweep paths of the tip and probe head according to the unique requirement of a sweep scan. The strategy is to first partition the free-form surface into simple elementary patches, such as cylinders, cones, or planar patches, and then plan an optimal sweep scan path for each patch. In terms of methodology, we first adopt a modified variational shape approximation method to partition the given surface into elementary patches and, based on a quality metric, a graph cut based algorithm is applied to refine the partition result. Next, rules for planning optimal sweep scan paths for a cylindrical patch, a conical patch, and a planar patch are proposed, respectively, which ensure efficient sweep scanning of these elementary type patches. Finally, we present an algorithm for automatically planning a sweep scanning path for an arbitrary pipe-like freeform surface, which strives to fully utilize the unique kinematic characteristics of the 5-axis inspection machine. Comparison experiments are performed between the proposed method and the popular isoparametric line scan method, and the results have verified the proposed methods and illustrated their advantages.