OpenLMD, an open source middleware and toolkit for laser-based additive manufacturing of large metal parts

We describe OpenLMD, a novel open-source toolkit for on-line multimodal monitoring and process control of Laser Metal Deposition (LMD). Building on existing open-source libraries (e.g. ROS, OpenCV, PCL), it enables the orchestration and virtualization of a robot cell for LMD and laser materials processing in general. It allows fast and intuitive process programming and planning, easy integration of multiple sensors and equipment, real-time process control, process virtualization and advanced visualization, and web-based interoperability. The approach adopted presents clear advantages in terms of scalability, and multimodal monitoring and data sharing capabilities. OpenLMD speeds up the deployment of laser metal deposition cells that feature CAD-based programming, advanced monitoring and control functionalities, and high interoperability. Its adoption allows focusing on a specific problem, without giving away functionalities that are important for performance demonstration. It facilitates collaborative research and the creation of datasets and benchmarks, in close-to-industrial settings. The ultimate goal is to enable working solutions for fully automated 3D printing of large metal parts, the challenging objective of many recent efforts on process modelling, monitoring, and control.