Pattern Optimization for Phyllotactic Fixed Abrasive Pads Based on the Trajectory Method

Fixed abrasive pads patterned with phyllotaxis theory of biology have been developed to be novel lapping and polishing pads. However, the influences of phyllotactic parameters on pad patterns were not deeply indicated. To design optimal pad patterns with fixed abrasives, the trajectory analysis method is adopted. As the uniformity of the abrasive trajectory has a significant influence on workpiece surface quality, the coefficient of trajectory distribution (CTD) is put forward in order to quantitatively evaluate the uniformity of trajectory distribution, and has been validated by simulation with three different pad patterns. Based on the method, the influences of phyllotactic parameters on the uniformity of trajectory distributions under different pad patterns are further studied. It is found that the phyllotactic angle parameter, which determines the pad pattern types, has a heavy influence on the trajectory distribution, but the phyllotactic density parameter has a little influence on trajectory distribution. Through analyzing the influences of phyllotacitc parameters on the values of CTD under a wide range, the periodic effects caused by the phyllotactic angle parameter are pointed out. Through appropriate combination of phyllotactic parameters, more optimal pad patterns can be obtained besides optimal machining parameters based on the proposed method.