•The automated 3D scanning system proposed in this research realizes the automatic calculation of scanning paths and the automatic splicing of scanning data, which greatly improves scanning ...efficiency and greatly reduces the difficulty of scanning complex objects.•This research proposes a virtual scanning principle, which accurately defines the conditions that a point on the surface of an object can be scanned by a binocular scanner, to provide a theory for the calculation of the optimal viewpoint in the scanning path. In addition, the virtual scanning principle has strong expansibility and can be easily adapted to different scanners.•This research proposes an automated 3D scanning path planning algorithm based on virtual scanning, which can realize the calculation of the global viewpoint of the measured object with a 3D digital model and the planning of the execution path, and the effectiveness of the algorithm and the accuracy greatly improves the technical level in the field of automated 3D scanning path planning.•This research proposes two splicing methods of scan data, one is a photogrammetry-based marker point stitching method with high accuracy, and the other is a high-efficiency mechanical stitching method based on system calibration results. The corresponding method can be selected according to different usage requirements.•In addition to the automated 3D scanning of complex parts, the calibration algorithm of the automated system proposed in this study has a good reference for automated applications such as automated welding and automated grabbing using robotic arms.
To achieve high-precision and high-efficiency 3D scanning of industrial parts, this research proposes an automated 3D scanning system based on path planning algorithms, in which the 3D scanning sensor is realized based on the principle of raster projection. The proposed automated scanning system is composed of a robotic arm, a 3D scanner, and a turntable to achieve a complete 3D scanning of the object to be measured. More precisely, this paper proposes a virtual 3D scanning principle, which can accurately determine whether a certain point on the CAD model can be scanned by a viewpoint. Further, this paper proposes a path planning algorithm based on the virtual 3D scanning principle, which can calculate the optimal scanning path required to scan the object according to the CAD model of the scanned object. Furthermore, to ensure the accuracy of the system, a high-precision system calibration method is proposed to establish the accurate positional relationship between various parts of the system. Firstly, this research proposes a camera calibration algorithm based on close-range photogrammetry, which can calculate the high-precision interior and exterior orientation parameters of the camera, and apply the method of calculating camera external parameters to the hand-eye calibration, making the accuracy of hand-eye calibration is also improved accordingly. In addition, this research proposes a photogrammetry-based projector calibration algorithm to determine the positional relationship between the projector and the camera in the 3D scanner, and a turntable calibration method to determine the positional relationship between the rotation center of the turntable and the camera. Eventually, according to different usage requirements, two 3D scanning data splicing methods are proposed. One is a high-efficient automatic splicing method based on the results of system calibration without pasting mark points, and the other is a high-precision data splicing method based on photogrammetry. Experimental results demonstrate that this system has higher accuracy and better performance in system calibration, scanning path calculation, and multi-view scanning data splicing.
3D scanning in the art & design industry Bugeja, Antonella; Bonanno, Martina; Garg, Lalit
Materials today : proceedings,
2022, 2022-00-00, Letnik:
63
Journal Article
Recenzirano
Disruptive technologies are often seen as a significant change or an invasive alternative way of operating. In reality, however, these can enhance processes. An example of such a disruptive ...technology is 3D scanning, which has applications in numerous fields from healthcare to product development and art to simulation. This paper investigates how 3D scanning technologies disrupt the Art & Design field through a literature review. The article also critically analyses the 3D scanning technology features, merits and limitations and explores opportunities and challenges.
Accurate bone registration is critical for computer navigation and robotic surgery. Existing registration systems are expensive, cumbersome, limited in accuracy and/or require intraoperative ...radiation. We recently reported a novel method of registration utilizing an inexpensive, compact, and X‐ray‐free structured‐light 3D scanner. However, this technique is not always practical in a real surgical setting where soft tissue and blood can obstruct the continuous line‐of‐sight required for structured‐light technology. We sought to remedy these limitations using a novel technique using rapid‐setting impression molding to capture bone surface features and scan the undersurface of the mold with a structured‐light scanner. The photonegative of this mold is compared to the preoperative computed tomography (CT)‐scan to register the bone. A registration accuracy study was conducted on 36 CT‐scanned femur sawbones, simulating typical exposure in hip/knee arthroplasty and bone tumor surgery. A cadaver experiment was also conducted to evaluate the feasibility of using the impression molding in a more realistic operating room setting. The registration accuracy of the proposed technique was 0.50 ± 0.19 mm. This was close to the reported accuracy of 0.43 ± 0.18 mm using a structured‐light scanner without impression molding (p = 0.085). In comparison, historical values for “paired‐point” and intraoperative CT image‐based registration methods currently used in modern robotic/computer‐navigation systems were 0.68 ± 0.14 mm (p = 0.004) and 0.86 ± 0.38 mm, respectively. The registration accuracy of the cadaver experiment was consistent with that of sawbone experiments. Although future studies are needed to extend to human subjects, this study shows that the impression molding method can produce comparable or better registration accuracy than the existing techniques.
AbstractObjectiveTo study the current status and applications of additive manufacturing (AM) in dentistry along with various technologies, benefits and future scope.MethodsA significant number of ...relevant research papers on the additive manufacturing application in dentistry are identified through Scopus and studied using bibliometric analysis that shows an increasing trend of research in this field. This paper briefly describes various types of AM technologies with their accuracy, pros and cons along with different dental materials. Paper also discusses various benefits of AM in dentistry and steps used to create 3D printed dental model using this technology. Further, ten major AM applications in dentistry are identified along with primary references and objectives.ResultsAdditive manufacturing is an innovative technique moving towards the customised production of dental implants and other dental tools using computer-aided design (CAD) data. This technology is used to manufacture elaborate dental crowns, bridges, orthodontic braces and can also various other models, devices and instruments with lesser time and cost. With the help of this disruptive innovation, dental implants are fabricated accurately as per patient data captured by the dental 3D scanner. The application of this technology is also being explored for the precise manufacturing of removal prosthetics, aligners, surgical templates for implants and produce models that for the planning of treatment and preoperative positioning of the jaws.
•Affordable 3D scanning and printing enables pinna replication for HRTF measurements.•Two printing materials yield accurate replicas, though harder one deviates at 2 kHz.•Perceptual discrimination ...between standardized and 3D printed pinnae is challenging.•Soft flexible printing material outperforms a harder alternative.
An important application of a head and torso simulator is to obtain head-related transfer functions (HRTFs) because it eliminates the methodological challenges inherent in human-based measurements. However, the use of these non-individual HRTFs to simulate virtual environments can lead to sound source localization errors in the listener. The emerging 3D scanning and printing technology make it possible to fabricate such intricate elements as the outer ear, thus several studies were initiated to explore the fabrication of individual dummy heads for various uses in acoustics. In this study we evaluate the feasibility of using low-cost 3D scanning and printing technology in the replication of human pinnae for use in HRTF measurements. A pair of commercially available standardized pinna simulators (silicone-rubber material) was scanned with a 3D scanner. Then two replicas were printed using two easily accessible materials of different hardnesses: acrylonitrile butadiene styrene (ABS, hard material) and thermoplastic polyurethane (TPU, soft material). A set of HRTFs was measured for each pair of pinnae to perform technical and perceptual evaluations, taking the commercial one as a reference. First, a numerical evaluation and a binaural cues analysis were performed on the HRTFs, followed by a psychophysical experiment of discrimination between auralized stimuli with the different HRTFs. The findings revealed overall similarities between the reference pinna and both replicas, leading to difficulties in their perceptual discrimination. However, the flexible soft material (TPU) demonstrated superior performance in both the technical and psychophysical validations. This discrepancy seems mostly attributable to a superior fit of the pinna with the head simulator. The harder material (ABS) had small irregularities in the fit preventing the formation of a resonance tube of adequate length to effectively reproduce the ear canal. These findings indicate the effectiveness of affordable 3D technology in the construction of pinna simulators for HRTF measurements as an alternative for commercial ones.
Abstract This paper presents a quadrotor drone designed for the 3D reconstruction of indoor environments using a depth camera and a tracking camera. The drone’s hardware and software components are ...described, including the Holybro X500V2 kit, the Intel RealSense T265 tracking camera, and the Intel RealSense D435i depth camera. The paper outlines the process of building a complete TF tree, capturing point clouds with RtabMap, and streaming video. The drone’s pose stabilization and successful test flight in an indoor environment are also discussed, including its ability to navigate through indoor spaces and provide accurate data for 3D reconstruction. The paper concludes with recommendations for future development, such as autonomous navigation and exploration of unknown areas. The results demonstrate the feasibility and potential of this drone for creating detailed and comprehensive maps of indoor environments.
3D scanning is one of the lesser talked about technologies used for designing, inspection, and quality control. This non-contact measuring technology converts a physical model into digital 3D ...Computer-Aided Design (CAD) with the help of various scanning software's. It is becoming an essential tool for producers who need an accurate dimensional inspection, virtual image, analysis, and even physical prototype manufacturing. This paper aims to discuss the potential of 3D scanning for the Industrial Sphere. It will take up 3D Scanners for practical industrial support and develop the Work-Flow Process of 3D Scanners for Industrial requirements. Further, the paper identifies and discusses sixteen major applications of 3D scanning from an Industrial perspective. 3D scanners use sensors to sense the data of any product. This technology can easily capture the virtual image of a physical part, and the same can be analysed, modified, printed, and stored. It allows for careful preparation of production systems involving machinery placement, facilities, repair and human ergonomic interplay. It is a vital performance measure to ensure the initial vision has been realised as intended. The automobile sector ensures that the produced product fits as per the manufacturer's requirement and for quality control. 3D scanning is helpful for reverse engineering, analysis, designing and measuring complex curved surfaces, education, architecture, survey, healthcare, quality monitoring, prototyping, development of industrial tools and many more. This technology uses advanced software for accurate measurement, storage, analysis, which helps increase the process's flexibility and reliability.
•Paper identifies the potential of 3D Scanning for the Industrial Sphere.•3D Scanning is a non-contact measuring technology used to converts a physical model into a digital 3D Computer-Aided Design (CAD) model through software.•A virtual image of a physical part can be analysed, modified, stored and printed.•In automobile sector, it ensures that the product fits as per the requirement of the manufacturer and quality control.•3D Scanning is helpful for reverse engineering, designing and measuring complex curved surfaces, education, architecture, survey, healthcare, quality monitoring, prototyping and development of industrial tools and devices.
Pollution of marine environments with microplastic particles (i.e. plastic fragments <5 mm) has increased rapidly during the last decades. As these particles are mainly of terrestrial origin, coastal ...ecosystems such as coral reefs are particularly threatened. Recent studies revealed that microplastic ingestion can have adverse effects on marine invertebrates. However, little is known about its effects on small-polyp stony corals that are the main framework builders in coral reefs. The goal of this study is to characterise how different coral species I) respond to microplastic particles and whether the exposure might II) lead to health effects. Therefore, six small-polyp stony coral species belonging to the genera Acropora, Pocillopora, and Porites were exposed to microplastics (polyethylene, size 37–163 μm, concentration ca. 4000 particles L−1) over four weeks, and responses and effects on health were documented.
The study showed that the corals responded differentially to microplastics. Cleaning mechanisms (direct interaction, mucus production) but also feeding interactions (i.e. interaction with mesenterial filaments, ingestion, and egestion) were observed. Additionally, passive contact through overgrowth was documented. In five of the six studied species, negative effects on health (i.e. bleaching and tissue necrosis) were reported.
We here provide preliminary knowledge about coral-microplastic-interactions. The results call for further investigations of the effects of realistic microplastic concentrations on growth, reproduction, and survival of stony corals. This might lead to a better understanding of resilience capacities in coral reef ecosystems.
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•Corals express differential responses to microplastics.•Corals show cleaning reactions but also feeding interactions with microplastics.•High microplastic concentrations may harm sensitive coral species.
Microplastic exposure causes differential responses of small-polyp stony corals, including cleaning mechanisms and feeding interactions but may also lead to bleaching and tissue necrosis.
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