Rolling-ball method and contour marching approach to identifying critical regions for complex surface machining

Abstract This paper presents a surface analysis method that includes a rolling-ball algorithm and a contour marching algorithm for identifying the critical regions that are unfeasible for machining. For a given cutter size, the algorithms automatically identify the regions that are unfeasible for machining and dichotomize the surface into the critical region and the machinable region. A rolling-ball method is used to find the starting points of the critical region boundary. A contour marching method is then used to construct the actual boundary of the critical regions by using the starting points found in the rolling-ball method. Different sets of tool paths can be generated for both the machinable region and the critical region. The proposed method allows manufacturing engineers to use different sizes of cutters to machine complex surface parts. Computer implementation and illustrative examples are presented in this paper.

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