自由曲面激光强化的轨迹优化研究

Trace Generation and Optimization of Free-form Surface in Laser Hardening

根据激光强化的工艺特性,从优化的角度出发,提出了一种基于平行截面法的改进算法。首先通过分析光斑的平均离焦量与光斑覆盖域曲率的关系,得到用自由曲面最大主曲率表示的工艺所允许的最大光斑尺寸公式;进而通过轨迹样本点分析的方式,得到统计平均的相邻平行截面间距。该方法综合考虑光斑大小、光斑间距、轨迹排距等多种因素,相较于一般的轨迹规划算法,能在保证加工效果的基础上有效提高加工效率。最后给出了一个算例,这一方法被用于汽车门板局部的激光强化加工轨迹规划,取得了良好的效果。

A modified parallel section method was introduced according to the characteristics of laser hardening. In order to obtain an optimized manufacturing path, the factors like spot size, spot distance and trace distance were taken into account. Firstly, the formula of maximum allowable spot size expressed by maximum main curvature of free-form surface was gotten via the analysis of the relation between average defocusing and curvature of the spot area. Then the statistical average distance between neighboring parallel sections was acquired using the analysis of sample trace points. Finally, the algorithm was used in laser manufacturing path planning for a door covering of a car. The efficiency was improved while a good effect acquired compared with normal parallel section method and some other algorithms.