Efficient five-axis scanning-inspection path planning for complex freeform surfaces

Freeform surface inspection is vital in manufacturing-related processes, and the newly emerged five-axis continuous sweep scanning technology offers to be a powerful means for accurate inspection of freeform surfaces. However, at present, for an arbitrary freeform surface, it still heavily depends on human intervention in planning an interference-free sweep scanning path, wherein typically the surface is simply partitioned into several subregions and sweep scanning paths are then individually planned for each subregion. In this paper, we present a novel and practical algorithm for automatically planning an efficient five-axis inspection path for an arbitrary freeform surface. The strategy is based on the idea of converting the inspection path planning problem into a set-covering problem, whose solution then gives out a near-minimum set of inspection paths for the freeform surface while subject to necessary constraints such as sampling resolution, collision-free, and others. Both computer simulation and physical inspection experiments of the proposed method have been conducted, and the results give a preliminary confirmation on the effectiveness and advantages of the proposed method.