1 天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室，天津 300072
2 天津高速公路集团有限公司科技与信息中心，天津 300384
3 中交远洲工程咨询有限公司养护部，河北 石家庄 050030
在公路的使用过程中，其表面会产生危害结构健康的裂缝，研究高效精确裂缝分割算法已成为交通运输领域的一个重要课题。在现有的基于图像的裂缝分割方法中，由数据驱动的深度学习技术展现出了强大的适用性。但基于神经网络的裂缝分割模型普遍缺乏对模型实时性的关注，为平衡模型精度和速度，选择合适的架构超参数，设计了一套架构超参数挑选框架，提出了实时路面裂缝分割模型（FastCrack-SPOS）。首先，设置不同的待选宽度（16，32，48，64，80）、深度（D1，D2，D3）、下采样倍率（1/4，1/8，1/32），构建出45组不同结构模型，分析每种参数对模型性能的影响；然后，使用神经架构搜索技术为模型每层自动搜索合适类型的卷积块，进而构建出最终模型。实验结果表明：所提架构超参数挑选框架在轻量级裂缝分割模型的设计上十分有效；构建出的FastCrack-SPOS在路面裂缝数据集上的交并比达62.88%；参数量仅0.29×106，相比现有模型，减少95%；处理1024×1024的图像的速度达147 frame/s，在速度和精度间取得了平衡，具有较高的实际应用价值。
图像处理 路面裂缝分割 轻量级网络 超参数选择 神经架构搜索 激光与光电子学进展
2023, 60(6): 0615006
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
We set up a pulsed beam steering system with a simple feedback control method. The system applies an integration circuit to process a 2 μs short pulsed beam with a repetition rate of 25 Hz, and employs an iteration method to correct the beam with a reasonable feedback gain factor. The beam steering system achieves a performance of 30 μm position accuracy and 30 μrad pointing accuracy, and it can not only compensate the drift of the laser source but also correct the external disturbance. The design can be directly applied as a lithography tool.
Chinese Optics Letters
2015, 13(Suppl): S21401
Author Affiliations
Abstract
We develope a simple method to stabilize the beam during propagation. Combination of the self-developed control module and the large diameter mirrors reconstruct the beam stabilization system, and some important procedures are presented, such as calibration and average filter. The results show that the horizontal pointing and vertical pointing are stabilized to within 8.43 and 7.59 μrad, and the beam horizontal position and vertical position are stabilized to within 2.16 and 2.11 μm respectively. The regulating time is within 84 ms. Thus the method presented is effective for the current stabilization system applied in lithography tools.
140.0140 Lasers and laser optics 140.3425 Laser stabilization Chinese Optics Letters
2014, 12(8): 081405
