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Flowchart illustrating the comparison process of two PPT phase images. This process is characterized by three main steps displayed from left to right: foreground extraction from PPT phase images, detection of adhesive bondings in foregrounds and pairwise comparison of adhesive bondings for difference detection.
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Carbon Fiber Reinforced Polymers (CFRPs) are composites whose interesting properties, like high strength-to-weight ratio and rigidity, are of interest in many industrial fields. Many defects affecting their production process are due to the wrong distribution of the thermosetting polymer in the upper layers. In this work, they are effectively and e...
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... section focuses on the description of the comparison between two PPT phase images. They are gray-scale images, like the one in the top-left corner of Fig. 2, in which darker shades of gray denote the presence of glue. This process is characterized by three main steps displayed from left to right in Fig. 3: 1) foreground extraction from PPT phase images; 2) detection of adhesive bondings in ...
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Citations
... In the context of the EU project FibreMap 4 [11], it allowed to inspect a carbon fiber preform in order to analyze its surface with a high accuracy and map carbon fibres on its model [12]. In ThermoBot 5 , it allowed to subtract the background from thermographic images, thus improving the speed and reducing false positives when detecting defects in carbon fiber parts [13]. Different examples of robot hand-eye configurations are reported in Figure 2. In our real experiments, the configuration in Figure 2(a) has been adopted. ...
Quality control methods and techniques have been investigated in different fields of manufacturing during the last decades. The introduction of robots in manufacturing processes has created a rapid deployment of robotic applications, leading to an increased research interest in the aspect of quality control in such industrial environments. This paper summarizes and presents a review of recent research and progress on quality control technologies, focusing on robot-based production systems. The role of different parameters affecting the control of quality in robotic tasks is also discussed, incorporating the impact of operator support systems in human robot collaborative environments. Research gaps and implications of quality control in robotic applications are also described, and a future outlook of research in the particular field is provided.
This paper addresses the problem of mapping large surfaces with a moving sensor. In particular, it proposes image registration and mapping algorithms that enable to use in continuous motion sensors that need multiple shots to perform a measurement. These methods exploit the knowledge of the shape of the part to inspect in a both efficient and accurate fashion, thus allowing to obtain a measurement quality comparable to that of static measurements, while guaranteeing fast sensor motion and thus short scanning times. This work describes the application of these methods for the mapping of carbon fibre parts with an inspection robot equipped with a sensor estimating 3D carbon fibre orientation from multiple 2D images captured with different illumination. Experiments on carbon fibre preforms of complex 3D shape demonstrates that this system accurately reconstructs in real-time the 3D fibre orientations of the outer layer of carbon fibre parts. Accuracy assessments report small errors within the tolerances allowed by the automotive industry on flat and generic 3D surfaces. The inspection robot system presented in this paper has been demonstrated both as an in-line quality inspection robot for production of carbon fiber preforms and as a measurement device for improving the draping process in the prototyping of carbon fibre parts.
Motion impacts and the long falling period of the mobile crossbeam are the main obstacles to development of a composite hydraulic press capable of achieving stable and rapid operation. Traditional uniform variable trajectory can be employed for mobile crossbeam variable motion to model speed change from fast to slow, but motion impacts, such as flexible impulses, always occur in real systems and are difficult to eliminate. This paper proposes a trajectory optimization method for the mobile crossbeam using Matlab. Three kinds of mathematical models were established describing falling trajectories, and a motion trajectory which is suitable for the falling process of mobile crossbeam was selected. Global optimization of minimum time for the selected trajectory was combined with a modified multi-island genetic algorithm. Simulation and experimental results indicated that motion performance had been improved after the global optimization of falling trajectory.
The strength of carbon fibre parts depends on the fibre arrangements all over them, but only manual and sparse checks are usually executed to assess their quality. Here, we present an automatic method for computing the fibre orientations in each part point and mapping them onto the 3D model of the part. This process is automated by a robot that moves the measurement sensor above the object to be scanned. Since this sensor needs to acquire multiple images of the same point with different illuminations for correctly estimating the fibre orientation, we developed algorithms for online image registration in presence of translational sensor motion. Moreover, we propose real-time methods for projection of the estimated orientation vectors to a 3D model. Experiments show that this software allows the accurate and fast mapping of carbon fibre parts by means of an industrial robot. Accuracy assessments report a measurement accuracy below 5\(^{\circ }\).
The strength of carbon fibre parts depends on the fibre arrangements all over them, but only manual and sparse checks are usually executed to assess their quality. Here, we present an automatic method for computing the fibre orientations in each part point and mapping them onto the 3D model of the part. This process is automated by a robot that moves the measurement sensor above the object to be scanned. Since this sensor needs to acquire multiple images of the same point with different illuminations for correctly estimating the fibre orientation, we developed algorithms for online image registration in presence of translational sensor motion. Moreover, we propose real-time methods for projection of the estimated orientation vectors to a 3D model. Experiments show that this software allows the accurate and fast mapping of carbon fibre parts by means of an industrial robot. Accuracy assessments report a measurement accuracy below 5 degrees.
