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

Three-Dimensional Scanning Applied for Flexible and In Situ Calibration of Galvanometric Scanner Systems

“…With either scanning system, the relationship between the mirror positions (joint space) and the Cartesian position in the workspace (task space) must be established. However, accurately mapping the joint and task space through the calibration is challenging due to the unknown geometrical, dynamical, optical, and thermal defects of the GLS system [ 5 , 6 ]. The influence of the individual defects varies; however, the thermal effects and the defects from mirrors and their rotary axes are commonly identified as the most significant contributors to laser beam drift [ 4 , 5 ].…”

“…Another approach is constructing a physical model of the GLS system [ 5 , 6 , 11 , 12 ]. These methods are categorised as model-driven approaches and generally rely on parameter optimisation based on accurate experimental data acquired either manually or through vision systems.…”

Applied Machine Vision: Advancing Quality Assurance and Quality Control in Industrial Manufacturing

“…This data may be evaluated and processed in real-time to raise operational efficiency, maintain quality standards, and reduce waste, allowing firms to improve productivity, maintain quality standards, and reduce waste in a continuous development cycle. In fact, after investing in smart factory projects, organisations report increases of up to 12% in areas like manufacturing production, factory utilisation, and labour productivity [37,38].…”

“…1.2. Industrial Cases However, GLS systems must be carefully calibrated to achieve the desired precision due to unknown thermal, mechanical, or optical defects [37,38]. Mounting the GLS system on an industrial manipulator adds flexibility and extends the workspace of the scanner but complicates calibration as the relative positioning to the work plane is no longer constant [2].…”

“…Other authors have proposed comprehensive physical models that describe the joint and task space relationship. These models rely on exhaustive parameter fitting using optimisation based on accurate experimental data and extensive prior knowledge of the optical and mechanical design of the GLS system [37,66,67,38]. As a result, model-based methods are computationally heavy, known to suffer from non-convex optimisation problems, and sensitive to slight changes in the hardware design, limiting their industrial application.…”