Tool radius compensation algorithm for three-axis NC peripheral milling

By thoroughly analyzing the characteristic of three-axis NC peripheral milling, based on geometry planar projection, a tool radius compensation algorithm for three-axis NC peripheral milling is established by using the similar method to that for planar contours NC milling. The space tool radius compensation for three-axis NC peripheral milling is reduced to three types of transitions processing. The first work is to calculate the coordinates (x and y) dimension of the transitions between neighbor linear segments in space by the projections intersection on the work plane, and the next work is to obtain the third coordinate(z) dimension of the transitions by reverse projection, consequently the formulas to calculate all sorts of transitions coordinates are derived. Based on UG platform, the simulation software of tool compensation for three-axis NC peripheral milling is programmed, the results of the simulation and NC milling examples show that the proposed space tool radius compensation algorithm for three-axis NC peripheral milling is highly effective and correct. The space tool radius offset G instructions with the developed approach will avoid NC codes regeneration due to tool wear or tool change during the three-axis NC flank milling process.