Study On The Position Algorithms Of Complex Cutter Multi-point Contact Machining The Surface

Tool positioning algorithms is the core of the numerical control (NC) programmingtechnology which affects directly to the machining precision and efficiency, and chosen areasonable tool position can improve the surface quality and efficiency. But for it has five degreesof freedom, the posture of the tool is became more flexible which make the tool positioncalculation more difficult. The existing tool position algorithm is mainly about multi-point contactprocessing which aim at gaining wide strip, but most of the multi-point tool position algorithm isresearch on the contact point and bases on the partial differential geometry which is contradicted tothe wide line. For this reason, based on the macro space positional, the research mainly on multi-point contact machining tool position algorithm was deeply implemented.In this paper, through analysis the character of self-adaptive tool system and the geometryproperty of torus, it concludes that the process of the self-adaptive toroidal tool to meet the work-piece surface is the motion process which from single-point contact to multi-point contact. Thenaccording to single-point contact force, establish the rotation axis of self-adaptive tool. Meanwhile,combining the analysis of space surface coordinates transformation and constraint conditions ofsurface-to-surface contact, indicate that dynamic equilibrium process of self–adaptive tool systemis the process that the distance between cutter and work piece invariant but the z-coordinatedecreasing. Then regards the actual process as an virtual process which think the distanceincreasing but z-coordinate invariant, and taking the virtual process as the model, establish anew tool position algorithm from macro space positional prospective which base on the dynamicequilibrium. The algorithm program is compiled using Matlab software, and it is used to calculatethe multi-point contact position data of Sine surface, non rotating ellipsoid surface and free-formopen mould surface. Design a self-adaptive toroidal tool system, simulate the dynamics process inAdams, using the contact simulation solver in Adams to calculate the position data, then throughcomparing the result between Adams and Matlab to verify the algorithm program correctness andeffectiveness. Finally, inversing the position date of the algorithms program calculating into robotjoint turn momentum, then verify it’s correctness and effectiveness further by driving the robotwhich with a toroidal tool system to contact the work-piece surface.