针对机车自动化打磨系统对位不精准、打磨厚度不均匀的问题,提出了一种基于激光扫描技术的打磨工具中轴线对位打磨点法线方向的算法。首先,计算线激光传感器扫描获取的待打磨件三维模型法向量,并将6种获取法线的算法进行对比,用效果最优的算法计算模型上各点的法线坐标;然后,通过手眼标定使法线坐标与打磨工具中轴线坐标可相互转换,并利用离线编程使两者实现精准对位;最后,建立打磨模型,计算理想的打磨厚度,测量精准对位和未精准对位的打磨厚度。实验结果表明,与未精准对位的算法相比,本算法能很好地解决打磨厚度不均匀的问题,且打磨结果与理想效果接近。

In order to solve the problem imprecise alignment and uneven grinding thickness in the automatic grinding system of the locomotive, a algorithm based on the laser scanning technology for the center axis of the grinding tool in the normal direction of the grinding point is proposed in this paper. First, the normal vector of the three-dimensional model of the workpiece to be polished obtained by scanning by the line laser sensor is calculated, and the 6 methods of obtaining normal is compared to obtain the optimal algorithm to calculate the normal coordinates of each point on the model. Then, through hand-eye calibration, the normal coordinates and the center axis coordinates of the grinding tool can be converted to each other, and the two can achieve precise alignment by using offline programming. Finally, a grinding model is established to obtain the ideal grinding thickness by calculation, and the grinding thickness values of the precise and imprecise alignment are measured. Experimental results show that, compared with imprecise alignment algorithm, the algorithm can well solve the problem of uneven grinding thickness and achieve the grinding effect consistent with the ideal grinding.