A finishing cutter selection algorithm for additive/subtractive rapid pattern manufacturing

The additive/subtractive rapid pattern manufacturing (RPM) process sequentially deposits thick material slabs and then machines them into desired geometries in a layer-by-layer manner. Although most rapid manufacturing systems mainly intend to increase flexibility in manufacturing rather than to reduce processing speed, it is still practical to choose the optimized sets of cutters and machining parameters specifically for each layer to improve both the machining quality and efficiency. This paper presents an algorithm to automatically select finishing cutter geometry, diameter, and calculate machining parameters for the RPM process. Inputs to this algorithm are StereoLithography file from a computer-aided design model and a cutter library. Finishing cutter selection is based on geometry accessibility and machining process efficiency analysis. The algorithm has been implemented in RPM automatic process planning software and the experimental result on a sample part is presented to show the efficacy of this algorithm.