To improve the polishing path and obtain better machining accuracy
the removal area generated by path on aspheric surface is analyzed
and a novel spiral tool path planning with uniform-overlap-rate is proposed. The removal area analysis following Hertz contact theory shows that the generally used Archimedes spiral fails to ensure the uniform and consistent machining accuracy due to varying contact of the removal area brought from changed elastic contact and projection path interval. Thus the concept of overlap rate is introduced to quantitatively describe the varying contact. The characteristics of varying overlap rate are revealed in the proposed path planning
and the changing relation between spiral and aspheric surface is established to guarantee the stable contact of the removal area between adjacent tool paths. The simulation shows that the range of overlap rate decreases from 56.1%-26.2% for Archimedes spiral path to 56.1%-55.3% for the proposed uniform-overlap-rate spiral path in aspheric surface polishing.
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references
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