Advances in Manufacturing ›› 2022, Vol. 10 ›› Issue (4): 556-570.doi: 10.1007/s40436-022-00392-3

• ARTICLES • 上一篇    

High-accuracy calibration for multi-laser powder bed fusion via in situ detection and parameter identification

Qi Zhong, Xiao-Yong Tian, Xiao-Kang Huang, Zhi-Qiang Tong, Yi Cao, Di-Chen Li   

  1. State Key Laboratory of Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
  • 收稿日期:2021-04-22 修回日期:2021-07-24 发布日期:2022-11-05
  • 通讯作者: Xiao-Yong Tian E-mail:leoxyt@mail.xjtu.edu.cn
  • 基金资助:
    This study was supported by the National High Technology Research and Development Program of China (863 Program) (Grant No. 2015AA042503), and the K. C. Wong Education Foundation.

High-accuracy calibration for multi-laser powder bed fusion via in situ detection and parameter identification

Qi Zhong, Xiao-Yong Tian, Xiao-Kang Huang, Zhi-Qiang Tong, Yi Cao, Di-Chen Li   

  1. State Key Laboratory of Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
  • Received:2021-04-22 Revised:2021-07-24 Published:2022-11-05
  • Contact: Xiao-Yong Tian E-mail:leoxyt@mail.xjtu.edu.cn
  • Supported by:
    This study was supported by the National High Technology Research and Development Program of China (863 Program) (Grant No. 2015AA042503), and the K. C. Wong Education Foundation.

摘要: Multi-laser powder bed fusion (ML-PBF) adopts multiple laser-scanner systems to increase the build envelope and build speed, but its calibration is an iterative and time-consuming process. In particular, multiple large-scale scan fields have a complex distortion in the overlap area, challenging the calibration process. In this study, owing to the enormous workload and alignment problems in the calibration of multiple scan fields, a novel calibration system is designed in this study to realize in situ auto-detection of numerous laser spots in the build chamber to ensure high efficiency and accuracy. Moreover, because the detectable area could not cover the entire build area and the detection data still contained errors, a virtual laser-scanner system was established by identifying the assembly defects and galvo nonlinearities of the ML-PBF system from the detection data, which served as the system's controller to improve calibration accuracy. The multi-field alignment error was less than 0.012%, which could avoid the intersection and separation of scan paths in multi-laser scanning and therefore meet the requirements for high-precision ML-PBF. Finally, the reliability of the method was verified theoretically using principal component analysis.

The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-022-00392-3

关键词: Powder bed fusion, Multi-laser technology, Galvo calibration, Assembly defects, System identification

Abstract: Multi-laser powder bed fusion (ML-PBF) adopts multiple laser-scanner systems to increase the build envelope and build speed, but its calibration is an iterative and time-consuming process. In particular, multiple large-scale scan fields have a complex distortion in the overlap area, challenging the calibration process. In this study, owing to the enormous workload and alignment problems in the calibration of multiple scan fields, a novel calibration system is designed in this study to realize in situ auto-detection of numerous laser spots in the build chamber to ensure high efficiency and accuracy. Moreover, because the detectable area could not cover the entire build area and the detection data still contained errors, a virtual laser-scanner system was established by identifying the assembly defects and galvo nonlinearities of the ML-PBF system from the detection data, which served as the system's controller to improve calibration accuracy. The multi-field alignment error was less than 0.012%, which could avoid the intersection and separation of scan paths in multi-laser scanning and therefore meet the requirements for high-precision ML-PBF. Finally, the reliability of the method was verified theoretically using principal component analysis.

The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-022-00392-3

Key words: Powder bed fusion, Multi-laser technology, Galvo calibration, Assembly defects, System identification