System and method for computer numerical control (CNC) tool without undercut features operations planning with the aid of a digital computer

A method for computer numerical control (CNC) tool without undercut features operations planning with the aid of a digital computer, comprising the steps of:

• obtaining by a computer comprising a processor, memory and storage, a geometric model of a part to be machined, the geometric model defining surfaces of the part to be machined;
• obtaining by the computer parameters for a plurality of CNC machining tools that do not possess undercut features when viewed along those CNC machining tools' spin axes, the parameters of each of the CNC machining tools comprising a plurality of orientations at which that CNC machining tool is able to longitudinally traverse a rotating cutting edge and cut material from a raw stock of the part, wherein the plurality of CNC machining tools are holdable by a CNC machine;
• obtaining by the computer a maximal set of translations for each of the CNC machining tools, each translation comprising one of the orientations of that CNC machining tool where that CNC machining tool's orientation will avoid collisions between a rotating cutting edge and the surfaces of the part and a maximal sub-volume of material removable from the part by that CNC machining tool when held by the CNC machine in that CNC machining tool's orientation for the translation;
• using by the computer the maximal set of translations to navigate through a hierarchically-structured search space that starts at an initial state and repetitively transitions to successive states until a goal condition is met by choosing one of a plurality of actions guided by a heuristic, wherein each of the initial state and successive states describe a negative volume of the part and one of the CNC machining tools held in that state by the CNC machine, each of the actions is associated with one of the orientations of the one of the CNC machining tools and the maximal machinable sub-volume removable in the one of the orientations, and wherein the heuristic is based on an aggregate cost associated with a group of the chosen actions and the negative volume that remains after subtracting the maximal sub-volume for each of the actions chosen, the aggregate cost associated with the chosen actions comprising a cost associated with switching between at least two of the CNC machining tools in the CNC machine for at least two of the chosen actions;
• and
• creating by the computer a plan for creating the part via actions of at least two of the CNC machining tools using a result of the navigation,
• performing by at least two of the CNC machining tools machining operations in the plan by machining off the part the maximal sub-volumes through traversals of the rotating cutting edge over the surfaces of the part.