A comparative study on the laser performance between bonding and non-bonding Er,Pr:GYSGG rods side-pumped by 970-nm laser diodes(LDs) is conducted for the thermal lensing compensation. The analyses of the thermal dist...A comparative study on the laser performance between bonding and non-bonding Er,Pr:GYSGG rods side-pumped by 970-nm laser diodes(LDs) is conducted for the thermal lensing compensation. The analyses of the thermal distribution and thermal focal length show that the bonding rod possesses a high cooling efficiency and weak thermal lensing effect compared with the conventional Er,Pr:GYSGG rod. Moreover, the laser characteristics of maximum output power, slope efficiency, and laser beam quality of the bonding rod with concave end-faces operated at 2.79 μm are improved under the high-repetition-rate operation. A maximum output power of 13.96 W is achieved at 150-Hz and 200-μs pulse width,corresponding to a slope efficiency of 17.7% and an electrical-to-optical efficiency of 12.9%. All results suggest that the combination of thermal bonding and concave end-face is a suitable structure for thermal lensing compensation.展开更多
针对工业管道与容器在自动化装配、焊接及在线检测过程中,环状端面基准拟合易受边界噪声、局部形变与采样不均影响而导致精度不足的问题,提出一种曲率-拓扑双驱动的端面基准平面拟合方法。该方法基于局部协方差张量的谱分解提取主曲率,...针对工业管道与容器在自动化装配、焊接及在线检测过程中,环状端面基准拟合易受边界噪声、局部形变与采样不均影响而导致精度不足的问题,提出一种曲率-拓扑双驱动的端面基准平面拟合方法。该方法基于局部协方差张量的谱分解提取主曲率,构建平整度与退化度指标,实现点云的非均匀稀疏化;进一步引入拓扑数据分析(Topological Data Analysis,TDA),通过构建Vietoris-Rips复形与持久同调分析提取具有闭合拓扑特征的骨架点集,从而嵌入环形端面的结构先验。基于骨架点集协方差矩阵的最小特征向量确定平面法向,实现高鲁棒性的姿态估计。实验表明,该方法平均绝对角度误差小于0.03°,单次拟合耗时低于0.03 s,相较于最小中值平方法提速约300倍,在主元分析、随机采样一致性等传统方法基础上精度提升约10倍。该方法精度高、鲁棒性强、实时处理速度快,无需人工干预,适用于复杂工业环境下的管道端面自动化定位与基准构建,可为智能制造中的焊接路径规划与在线检测提供可靠技术支撑。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51872290,51702322,and 51802307)the National Key Research and Development Program of China(Grant No.2016YFB1102301)
文摘A comparative study on the laser performance between bonding and non-bonding Er,Pr:GYSGG rods side-pumped by 970-nm laser diodes(LDs) is conducted for the thermal lensing compensation. The analyses of the thermal distribution and thermal focal length show that the bonding rod possesses a high cooling efficiency and weak thermal lensing effect compared with the conventional Er,Pr:GYSGG rod. Moreover, the laser characteristics of maximum output power, slope efficiency, and laser beam quality of the bonding rod with concave end-faces operated at 2.79 μm are improved under the high-repetition-rate operation. A maximum output power of 13.96 W is achieved at 150-Hz and 200-μs pulse width,corresponding to a slope efficiency of 17.7% and an electrical-to-optical efficiency of 12.9%. All results suggest that the combination of thermal bonding and concave end-face is a suitable structure for thermal lensing compensation.
文摘针对工业管道与容器在自动化装配、焊接及在线检测过程中,环状端面基准拟合易受边界噪声、局部形变与采样不均影响而导致精度不足的问题,提出一种曲率-拓扑双驱动的端面基准平面拟合方法。该方法基于局部协方差张量的谱分解提取主曲率,构建平整度与退化度指标,实现点云的非均匀稀疏化;进一步引入拓扑数据分析(Topological Data Analysis,TDA),通过构建Vietoris-Rips复形与持久同调分析提取具有闭合拓扑特征的骨架点集,从而嵌入环形端面的结构先验。基于骨架点集协方差矩阵的最小特征向量确定平面法向,实现高鲁棒性的姿态估计。实验表明,该方法平均绝对角度误差小于0.03°,单次拟合耗时低于0.03 s,相较于最小中值平方法提速约300倍,在主元分析、随机采样一致性等传统方法基础上精度提升约10倍。该方法精度高、鲁棒性强、实时处理速度快,无需人工干预,适用于复杂工业环境下的管道端面自动化定位与基准构建,可为智能制造中的焊接路径规划与在线检测提供可靠技术支撑。
