Development of trinocular CCD-based optical detector for real-time monitoring of laser cladding

Monitoring of laser metal deposition height by means of coaxial laser triangulation

“…The deposition height can be also extracted from the 3D reconstruction of the deposited object, e.g., obtained by means correlation analysis algorithms for images taken with off-axis cameras from one or more points of view as reported by several studies [21][22][23][24][25]. These approaches give rich information and seem to be suitable for research purposes, while their usage for production applications might be limited by the complexity of the monitoring setups, whose size might also obstruct the movements of the deposition equipment.…”

Online Calculation of Melt Pool Cooling Rate with Automatic Background Correction

“…The controlled parameter is melt pool width, obtained after binarization with a constant threshold. The implementation of a closed-loop control system for cladding is presented in [10]. A dynamic threshold is used to reduce the fuzziness level of the image, erasing parts of the image (such as flashes) not to be considered as part of the melt pool.…”

“…It can be noticed that none of the aforementioned works implements background correction, and a dynamic threshold is only used in [10], but for a different purpose from the one in this paper.…”

Improved Melt Pool Monitoring Systems for Direct energy Deposition Processes

“…Asselin et al produced a trinocular camera system that used three cameras equally spaced around the laser cladding head [34]. This system captured images from two out of three cameras depending on the angle of the melt pool.…”

“…Kruth et al published multiple papers using a system that combined a CMOS camera with a Figure 5: A schematic representation of the trinocular set-up used to perform melt pool measurements in experiments carried out by Asselin et al [34].…”