Hunan Luojia is dedicated to the research and integration of online monitoring modules for metal additive manufacturing. Our goal is to achieve real-time monitoring of parameters such as melt pool temperature and morphology, powder quality, planar defects and contour accuracy, internal defects, chamber atmosphere and element content, as well as stress and strain. We have established a full lifecycle digital twin model for equipment development and process development. By applying advanced information processing techniques (including signals, images, and vision) and machine learning methods in the "measure-diagnose-control" process of selective laser melting (SLM), we enable rapid processing, analysis, and process feedback of monitoring data. We aim to enhance the mechanical performance, particularly fatigue properties, of printed components, ultimately achieving high-quality printing that meets aerospace requirements.