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Purpose This study aims to report the development of a provisional robotic cell for additive manufacturing (AM) of metallic parts. To this end, the paper discusses cross-disciplinary concepts related to the development of the robotic cell and the associated command and control system such as the Computer-Aided Design (CAD) interface, the slicing software and the path planning for the robot manipulator toward printing the selected workpiece. This study also reports the development of a virtual production cell that simulates the AM toolpath generated for the desired workpiece, the adaptation of the simulation environments to enable AM and the development of a user application to setup, command and control the AM processes. If a digital twin setup is efficiently built, with a good correlation between the simulation environment and the real systems, developers may explore this functionality to significantly reduce the development cycle, which can be very long in AM applications where metallurgic properties, part distortion and other properties need to be monitored and controlled. Design/methodology/approach To generate the robot manipulator path, several simulation programs were considered, resulting in different solutions to program and control the robot of choice [in this study, Kuka and Asea Brown Boveri (ABB) robots were considered]. By integrating the solutions from Slic3r, Inventor, Kuka.Sim, Kuka.Officelite, RobotStudio and Visual Studio software packages, this study aims to develop a functional simulation system capable of producing a given workpiece. For this purpose, a graphical user interface (GUI) was designed to provide the user with a higher level of control over the entire process toward simplifying the programming and implementation events. Findings The presented solutions are compatible with the simulation environments of specific robot manufacturers, namely, ABB and Kuka, meaning that the authors aim to align the developments with most of the currently realized AM processing cells. In the long-term, the authors aim to build an AM system that implements a produce-from-CAD strategy i.e. that can be commanded directly from the CAD package used to design the part the authors are interested in. Research limitations/implications This study attempts to shed light on the industrial AM, a field that is being constantly evolved. Arguably, one of the most important aspects of an AM system is path planning for the AM operation, which must be independent of the robotic system used. This study depicts a generic implementation that can be used with several robot control systems. The paper demonstrates the principle with ABB and Kuka robots, exploiting in detail simulation environments that can be used to create digital twins of the real AM systems. This is very important in actual industrial setups, as a good correlation between the digital twins (simulation environment and real system) will enable developers to explore the AM system in not only a more efficient manner, greatly reducing the development cycle but also as a way to fully develop new solutions without stopping the real setup. In this research, a systematic review of robot systems through simulation environments was presented, aiming to emulate the logic that is, used in the production cell development, disregarding the system brand. The adopted digital twin strategy enables the authors to fully simulate, both operationally and functionality, the real AM system. For this purpose, different solutions were explored using robots from two different manufacturers and related simulation environments, illustrating a generic solution that is not bound to a certain brand. Practical implications Using specific programming tools, fully functional virtual production cells were conceived that can receive the instructions for the movements of the robot, using a transmission control protocol/internet protocol. Conversion of the CAD information into the robot path instructions for the robot was the main research question in this study. With the different simulation systems, a program that translates the CAD data into an acceptable format brings the robot closer to the automatic path planning based on CAD data. Both ABB and Kuka systems can access the CAD data, converting it to the correct robot instructions that are executed. Eventually, a functional and intuitive GUI application capable of commanding the simulation for the execution of the AM was implemented. The user can set the desired object and run a completely automatic AM process through the designated GUI. Comparing ABB simulation with the Kuka system, an important distinction can be found, namely, in the exportation of the programs. As the Kuka program runs with add-ons, the solution will not be exported while maintaining its functionality, whereas the ABB program can be integrated with a real controller because it is completely integrated with modules of the virtual controller. Originality/value To conclude, with the solutions exploited, this study reports a step forward into the development of a fully functional generic AM cell. The final objective is to implement an AM system that is, independent of any robot manufacturer brand and uses a produce-from-CAD strategy (c.f. digital manufacturing). In other words, the authors presented a system that is fully automatic, can be explored from a CAD package and, consequently, can be used by any CAD designer, without specific knowledge of robotics, materials and AM systems.

Purpose Additive manufacturing (AM) is a rapidly evolving manufacturing process, which refers to a set of technologies that add materials layer-by-layer to create functional components. AM technologies have received an enormous attention from both academia and industry, and they are being successfully used in various applications, such as rapid prototyping, tooling, direct manufacturing and repair, among others. AM does not necessarily imply building parts, as it also refers to innovation in materials, system and part designs, novel combination of properties and interplay between systems and materials. The most exciting features of AM are related to the development of radically new systems and materials that can be used in advanced products with the aim of reducing costs, manufacturing difficulties, weight, waste and energy consumption. It is essential to develop an advanced production system that assists the user through the process, from the computer-aided design model to functional components. The challenges faced in the research and development and operational phase of producing those parts include requiring the capacity to simulate and observe the building process and, more importantly, being able to introduce the production changes in a real-time fashion. This paper aims to review the role of robotics in various AM technologies to underline its importance, followed by an introduction of a novel and intelligent system for directed energy deposition (DED) technology. Design/methodology/approach AM presents intrinsic advantages when compared to the conventional processes. Nevertheless, its industrial integration remains as a challenge due to equipment and process complexities. DED technologies are among the most sophisticated concepts that have the potential of transforming the current material processing practices. Findings The objective of this paper is identifying the fundamental features of an intelligent DED platform, capable of handling the science and operational aspects of the advanced AM applications. Consequently, we introduce and discuss a novel robotic AM system, designed for processing metals and alloys such as aluminium alloys, high-strength steels, stainless steels, titanium alloys, magnesium alloys, nickel-based superalloys and other metallic alloys for various applications. A few demonstrators are presented and briefly discussed, to present the usefulness of the introduced system and underlying concept. The main design objective of the presented intelligent robotic AM system is to implement a design-and-produce strategy. This means that the system should allow the user to focus on the knowledge-based tasks, e.g. the tasks of designing the part, material selection, simulating the deposition process and anticipating the metallurgical properties of the final part, as the rest would be handled automatically. Research limitations/implications This paper reviews a few AM technologies, where robotics is a central part of the process, such as vat photopolymerization, material jetting, binder jetting, material extrusion, powder bed fusion, DED and sheet lamination. This paper aims to influence the development of robot-based AM systems for industrial applications such as part production, automotive, medical, aerospace and defence sectors. Originality/value The presented intelligent system is an original development that is designed and built by the co-authors J. Norberto Pires, Amin S. Azar and Trayana Tankova.

Purpose This paper aims to introduce, in a tutorial form, a collection of procedures, tools and applications that can be used to explore robotics fundamentals and automatically generate kinematic and dynamic models from computer-aided design (CAD) packages, to create representations of the robot manipulator understudy so that a user can generate trajectories and to simulate and visualize the robot motion using several programming, simulation and developing tools. In this paper, the authors are particularly interested in advanced three-dimensional design packages such as Inventor and SolidWorks, interactive mathematical and simulation environments such as Matlab, Simulink, Simscape Multibody and Robot Operating System, and several application development languages such as C# and Python. A few of them will be used throughout the paper in a collection of examples that use the new Kassow 810 collaborative robot as a test-case demonstration. In the process, the authors expect readers to fully understand how to use all these tools to other machines and to their own designs. Design/methodology/approach Consequently, the paper follows a step-by-step practical procedure, fully tested and explained using the already mentioned state-of-the-art collaborative robot, guiding the reader from the design, modeling, simulation and application development phases, which may be applied to other machines and robotic designs. Findings The results clearly show that the procedure of starting from a CAD design to generate the kinematic and dynamic models of a robot manipulator create representations of the robot, generate trajectories and simulate/visualize the robot motion is feasible and accessible to a general user (using standard tools). Research limitations/implications Although the paper uses a few particular software packages, the concepts and kept general, which means that they can be used with other equivalent tools. With that objective in mind, the paper introduces the basic robotics concepts involved, further increasing in this way its tutorial structure. Originality/value Consequently, the presented procedure has the inherent value of introducing robotics fundamentals in a practical way, but also of demonstrating how readers can build and explore advanced robotic designs using common design, simulation and programming tools.

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