The presented work here is devoted to the definition of innovative methodologies to speed up the programming time of a robotized deburring task. The proposed solutions are defined in a standard cast ...iron foundry scenario, where the deburring workstations are equipped with flexible but inaccurate fixturing system, the working environment is dirty, and the production is characterized by small batches. The developed system exploits a 3D vision sensor, namely a single-point laser displacement sensor (SP-LS), in combination to a handshaking communication process for the robot-sensor information synchronization. Such approach enables the robot to be used as a measuring instrument allowing a fast reconstruction of 3D images extremely robust in hard working conditions. Adopting a two-stage methodology, the comparison of the reconstructed 3D point cloud with the nominal 3D point cloud allows the automatic adjustment of the robot deburring trajectories. An experimental campaign demonstrates the feasibility and the effectiveness of the proposed solutions.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
For the automatic laser deburring of ceramic cores, this study proposed a method for generating deburring tool paths by combining the computer-aided design/computer-aided manufacturing (CAD/CAM) ...approach with two-step coarse and fine point cloud registrations method. Specifically, the CAD/CAM approach was employed to generate the ideal tool paths based on the CAD model, and the coarse registration ensured the global optimal solution of the subsequent fine registration. Considering the complex structure and the uneven shrinkage deformation of ceramic cores, the hybrid and local fine registration method was proposed to optimize the ideal tool paths in order to generate deburring tool paths. Moreover, the fine registration also eliminated the influence of inconsistent clamping errors of ceramic cores on the final accuracy of deburring tool paths. In order to select the optimal local fine registration methods, focusing on the accuracy of deburring tool paths, four rigid and non-rigid point cloud registration methods based on the iterative closest point algorithm were compared. Furthermore, a method for evaluating the accuracy of deburring tool paths was proposed. Finally, a repeatability experiment was performed to verify the accuracy and robustness of the proposed method. The generated deburring tool paths were verified and its effectiveness was proven on a five-axis laser processing equipment.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Details of coaxial radio components are small-sized, having high accuracy requirements of up to 7 qualifications, and construction with hard-to-reach surfaces. Burrs on these parts are not allowed by ...the technical requirements. It is not possible to exclude the appearance of burrs at the stage of blade machining. For deburring, mechanical and electro physicochemical methods are possible. The article provides an overview of electro physicochemical methods for deburring small-sized high-precision parts of coaxial radio components. The features of the application of these methods for these parts, their advantages and disadvantages are given.
Controlling the contact force on workpieces is a challenging task for industrial deburring operations. To solve this issue, a novel constant force mechanism (CFM) based on the combination of positive ...and negative stiffness mechanism is proposed by using folding beam and bi-stable beam mechanisms. Without using any additional sensors and control algorithms, the proposed CFM can produce a travel range in constant force manner. In this paper, the design concepts, analytical model, finite element analysis (FEA) simulation and experimental studies are presented and discussed. Firstly, a novel spatial CFM is proposed and the pseudo rigid body (PRB) method is used to establish the mathematical model of the whole mechanism. Then, the FEA simulation is performed to validate the correctness of theoretical analysis. In addition, to eliminate the force variation, particle swarm optimization (PSO) method is utilized to find optimal architectural parameters solutions of the CFM. Finally, the experimental tests are performed to verify the performance of the designed CFM. The configuration design and parameter optimization proposed in this paper can be further applied to the design of other types of CFM mechanisms for polishing operations as well.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Manual removal of burrs on castings introduces health, safety, and environmental concerns. Automated removal of highly variable casting burrs could improve safety, but requires a solution based on ...robots, smart sensors, and advanced algorithms to tackle the problem in a flexible and cost-effective way. This paper presents a system for automatic tool trajectory generation for robotic deburring of cast parts with a specific focus on the robotic tool trajectory generation algorithm. The system generates a robotic trajectory adapted to the specific workpiece based on CAD model and 3D scans of the workpiece. The registered 3D scans and CAD model is used to generate a 3D model of each individual workpiece. This is fed into the tool trajectory generation algorithm. The algorithm uses the generated 3D model as well as a priori knowledge of the casting process to generate the tool trajectory. The tool trajectory planning algorithm has been tested on a set of various 3D models of cast parts, and the generated robotic tool path has been both simulated and tested on a KUKA KR 60.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The development of modern manufacturing requires key solutions to enhance the intelligence of manufacturing such as digitalization, real-time monitoring, or simulation techniques. For smart robotic ...manufacturing, the modern approach regarding robot programming and process planning aims for both high efficiency and energy-awareness. During the design and manufacturing stages, optimization becomes crucial and can be fulfilled by means of appropriate digital manufacturing tools. This paper presents the development of a Digital Twin for a robotic deburring workcell along with the process planning and robot programming. Considering a large size workpiece, a new robot programming solution was implemented, based on image processing to safely re-machine only areas where burrs could not be completely removed in the main deburring routine. The work also covers the development of a new web platform to remotely monitor the robotic workcell, to trigger alerts for unexpected events and to allow the control to authorized personnel enabled by the employment of robot web services following an architectural RESTful style which establishes a communication link to the robot virtual controller. The aim of this research is to integrate the Digital Twin with the innovative proposals of Industry 4.0, offering a project-based model of smart robotic manufacturing and experience concepts such as Cyber-Physical System, digitalization, data acquisition, continuous monitoring, and intelligent solutions in a novel approach. Furthermore, the work covers energy consumption strategies for energy-aware robotic manufacturing. Finally, the results of an energy-efficient motion planning along with signal-based scheduling optimization of the robotic deburring cell are discussed.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The micro structures milled on Ti6Al4V tubes are so narrow that to be damaged in deburring by conventional methods. In this study, a deburring method for the top burrs on micro slots of Ti6Al4V tubes ...was proposed. The ultra-small-grinding (USG) tool was applied to grind the roots of top burrs for deburring. The method can replace the big milling burrs with the small grinding burrs. A prediction model of the grinding burr size considering workpiece shape and tool deflection was proposed. The ideas of volume balance and energy balance were applied in modeling. Corresponding experiments were conducted with ultra-small-grinding (USG) tools with diameters ~ 100 µm. The effectiveness of the method and the prediction model were proved by the experimental results. The varieties of the grinding burrs in different deburring parameters were studied. The size of grinding burr increase with the increasing of the feeding velocity. The proper deburring parameters are 1–3 mm/min feeding velocity and 10 µm axial cutting depth. The morphologies of the grinding burrs can be divided into four types, which are continuous stacked tiny burr, continuous stacked small burr, discontinuous stacked modern burr, and discontinuous single big burr. The grinding burrs along the side of micro slot can be divided into four kinds of contours, which are smooth contour, rippled contour, wavy contour, and surge contour. The grinding burrs along the sides of micro slots were stacked in the form of laminated tiles, and some strip structures were on the surface of the grinding burrs.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper is aimed at reviewing the fundamental aspects and recent developments in electropolishing process. The fundamental theories in the material removal mechanism of electropolishing process ...are introduced. Since electropolishing is a complicated process including electricity and chemical reaction, it is influenced by many process factors, such as current density, temperature, electrolyte types and workpiece rotation. There is still no available theory which can explain the electropolishing process well, especially when some recent developments were established, the material removal mechanism became more complicated in understanding. However, as the recent developments in the laser machining, additive manufacturing and biomedical device manufacturing, there is a need to use the electropolishing method to post-treat the surface obtained from these methods due to the high industrial requirements. The electropolishing method utilizes the electrochemical reaction between the anodic and cathodic electrodes, when the current is switched on with a DC/AC power supply, to remove the material from the surface of workpiece, hence, the polishing processes of various materials show quite different characteristics on the needed electrolyte types, current densities and so on. Therefore, the electropolishing of various materials is also reviewed in this work. The electropolishing has been not only used for the surface finishing of metal, but also for the passivation, deburring and pattern formation. Finally, a perspective in the development of electropolishing technique is presented to provide a reference for the further research.
•The development of the material removal mechanisms in electropolishing is elaborated.•The influences of the main process factors on the electropolishing process are analysed.•The application and recent development of electropolishing technique are summarized.•Fill the knowledge of understanding the state-of-the-art of the EP fundamentals and technologies.•The outlook of the future research and development in electropolishing is suggested.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A study on the use of deep learning model in the field of neutron image restoration is performed.•A lightweight, convenient and efficient deep learning network is proposed for neutron image ...restoration.•The X-ray dataset solves the problem of lack of real neutron image datasets.•The pre-training model achieves good results in real neutron image restoration.
Traditional neutron image restoration (NIR) methods lack flexibility and generalization in dealing with multiple image restoration tasks, which indirectly limits the practical applications of neutron images. Deep convolutional neural networks (CNNs) have achieved impressive success in image restoration, so this paper preliminarily explores and applies deep CNNs in NIR. Considering the characteristics and applications of neutron images, we propose a fast and lightweight densely connected attention U-Net (DAUNet) for NIR. We strengthen the network’s attention to the image structural information and the processing at different frequencies by adding an attention mechanism to the symmetric skip connection under each scale of U-Net. The proposed DAUNet uses a single model for recovering images with different degradations, such as additive noise and blur. Extensive experiments on synthetic and real neutron-degraded images are conducted, and the results show that DAUNet is effective and efficient in NIR and achieves satisfactory results in terms of both comprehensive performance (PSNR) and intrinsic metrics (parameters, memory cost and running time), which are highly attractive for practical applications. In addition, to address the problem of lacking real NIR datasets, we use X-ray images that the imaging principles are closer to that of neutron imaging as data drivers for the network.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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