Metallic Objects Research Articles

Wireless Remote Controlled Multi-Purpose Robot using Raspberry PI

Over the past five decades, robotics and associated technologies have evolved into indispensable components across numerous industries, particularly in advanced manufacturing. Moreover, their application has extended beyond production-centric domains to encompass pivotal roles in military and law enforcement sectors, owing to advancements in sophistication, reliability, and compactness. This paper proposes the implementation of a real-time object detection system capable of precisely identifying and locating recognized objects, presenting a significant and practical advancement. Integrating various modules such as GSM and GPS with a Raspberry Pi, along with an array of sensors including metal and flame sensors, an L293 Motor driver, HC-SR04 Ultrasonic sensor, and HC-05 Bluetooth, this system facilitates seamless recognition and localization of objects in real-time. The Bluetooth connectivity feature enables remote control of the device, while a built-in camera captures images of unidentified individuals, thereby enhancing its surveillance capabilities. The incorporation of a motor driver ensures secure and controlled movement of the robot, while the ultrasonic sensor detects obstacles within its proximity. Additionally, the metal sensor swiftly identifies metallic objects, relaying their locations to the administrator, whereas the flame sensor promptly detects fires, enabling the system to dispatch location data for immediate response. This holistic approach renders the proposed system a versatile tool applicable across a spectrum of scenarios, ranging from security and surveillance operations to emergency response initiatives.

Update on airway obstruction in children, with a nursing approach airway obstruction in children

Airway obstruction in children is an important cause of infant mortality; The most common origin is with the ingestion of nuts (60 % to 80 %), followed less frequently by others such as food remains, toys, metal objects (coins), balloons. The symptoms will depend on the point in the airway where said object is located: larynx, trachea or bronchi, with the right main bronchus being the most common. Therefore, it is necessary for the population to know how to prevent suffocation, the signs and symptoms derived from aspiration of an object, and the maneuvers that should be performed

An interactive task-based method for the avoidance of metal artifacts in CBCT

PurposeIntraoperative cone-beam CT imaging enables 3D validation of implant positioning and fracture reduction for orthopedic and trauma surgeries. However, the emergence of metal artifacts, especially in the vicinity of metallic objects, severely degrades the clinical value of the imaging modality. In previous works, metal artifact avoidance (MAA) methods have been shown to reduce metal artifacts by adapting the scanning trajectory. Yet, these methods fail to translate to clinical practice due to remaining methodological constraints and missing workflow integration.MethodsIn this work, we propose a method to compute the spatial distribution and calibrated strengths of expected artifacts for a given tilted circular trajectory. By visualizing this as an overlay changing with the C-Arm’s tilt, we enable the clinician to interactively choose an optimal trajectory while factoring in the procedural context and clinical task. We then evaluate this method in a realistic human cadaver study and compare the achieved image quality to acquisitions optimized using global metrics.ResultsWe assess the effectiveness of the compared methods by evaluation of image quality gradings of depicted pedicle screws. We find that both global metrics as well as the proposed visualization of artifact distribution enable a drastic improvement compared to standard non-tilted scans. Furthermore, the novel interactive visualization yields a significant improvement in subjective image quality compared to the state-of-the-art global metrics. Additionally we show that by formulating an imaging task, the proposed method allows to selectively optimize image quality and avoid artifacts in the region of interest.ConclusionWe propose a method to spatially resolve predicted artifacts and provide a calibrated measure for artifact strength grading. This interactive MAA method proved practical and effective in reducing metal artifacts in the conducted cadaver study. We believe this study serves as a crucial step toward clinical application of an MAA system to improve image quality and enhance the clinical validation of implant placement.

Foreign body in a Zenker's diverticulum.

Zenker's diverticulum (ZD) is an uncommon disorder that can cause dysphagia with risk of aspiration. While surgical treatment has been the mainstay for many years, endoscopic diverticulotomy has emerged as a first-line option with favorable outcomes. We present the case of a 93-year-old woman with no significant past medical history who was diagnosed with a 6 cm ZD. Due to dysphagia, she experienced significant weight loss and was at risk of malnutrition. She developed aspiration pneumonia and required admission to our center. Given her condition and inability to swallow, a nasogastric tube was placed under radiological guidance for nutritional support pending definitive treatment. On radiographic localization of the ZD, a radiopaque metallic density image was observed that had not been identified in previous imaging. Suspecting a possible retained foreign body in the large diverticulum, a gastroscopy was performed. During the procedure, the ZD was accessed and a 10 mm metallic object was identified. The object was extracted using a Roth net, confirming the suspicion of a foreign body lodged in the ZD. The metallic piece was later identified as a patient's dental prosthesis. After resolution of the aspiration pneumonia, endoscopic-assisted diverticulotomy was performed. The procedure was carried out under deep sedation with cricopharyngeal myotomy without immediate complications. After 48 hours of hospitalization, the patient was discharged without requiring a nasogastric tube for feeding.

Location-Aware Range-Error Correction for Improved UWB Localization.

In this paper, we present a novel localization scheme, location-aware ranging correction (LARC), to correct ranging estimates from ultra wideband (UWB) signals. Existing solutions to calculate ranging corrections rely solely on channel information features (e.g., signal energy, maximum amplitude, estimated range). We propose to incorporate a preliminary location estimate into a localization chain, such that location-based features can be calculated as inputs to a range-error prediction model. This way, we can add information to range-only measurements without relying on additional hardware such as an inertial measurement unit (IMU). This improves performance and reduces overfitting behavior. We demonstrate our LARC method using an open-access measurement dataset with distances up to 20 m, using a simple regression model that can run purely on the CPU in real-time. The inclusion of the proposed features for range-error mitigation decreases the ranging error 90th percentile (P90) by 58% to 15 cm (compared to the uncorrected range error), for an unseen trajectory. The 2D localization P90 error is improved by 21% to 18 cm. We show the robustness of our approach by comparing results to a changed environment, where metallic objects have been moved around the room. In this modified environment, we obtain a 56% better P90 ranging performance of 16 cm. The 2D localization P90 error improves as much as for the unchanged environment, by 17% to 18 cm, showing the robustness of our method. This method evolved from the first-ranking solution of the 2021 and 2022 International Conference on Indoor Position and Indoor Navigation (IPIN) Competition.

PREHISTORIC KASHMIR: UNRAVELING THE CULTURAL HERITAGE OF NEOLITHIC ARTIFACTS

In the present paper, we have carried out a systematic study of the important archaeological remains recovered from the Neolithic sites in the Kashmir valley that were excavated by the Archaeological Survey of India. It is also evident from the earlier studies carried out by various Scholars that more than fifty-five Neolithic sites were discovered in the Jammu and Kashmir region, and two in the Ladakh region. The Neolithic remains were found at nine sites during the field work but among these only four Neolithic sites were systematically excavated extensively. These are Burzahom, Gufkral, Simthan and Kanispur. The archaeological artifacts reported from these Neolithic sites in the Kashmir valley were mainly pottery, terracotta objects, metal objects, stone objects, paste Objects and semi-precious stones. In the present paper, an analytical estimation of Neolithic culture such as the structural remains, ceramic assemblages, metal objects, terracotta objects, shell objects, bone objects, and stone objects are studied. The information provided in the present paper about the Neolithic culture in Kashmir is based on the excavations of these four Neolithic archaeological sites in Kashmir Valley such as Burzahom, Gufkral, Simthan and Kanispur. Many other Neolithic settlements are reported in the Kashmir valley which are still waiting for the excavation.

Where are the missing boatyards? Steaming pits as boat building sites in the Nordic Bronze Age

Abstract The boat stands out as a prominent symbol of the Nordic Bronze Age, depicted at thousands of rock art sites and on several metal objects throughout Scandinavia. Paradoxically, direct evidence of these boats is scarce, and the locations where boats were constructed remain largely elusive. In this paper, we put forth the proposition that many ostensibly mislabelled cooking pits along the coast might actually be remnants of steaming pits employed in boat building. By drawing on analogous parallels from ethnography and examining three Bronze Age cases from the western coast of Sweden and Eastern Norway, we hypothesize that sizable pits near the sea, characterized by fire-cracked stones and charcoal, are indicative of prehistoric boat building sites. Additionally, these results align with a broader objective of our paper, aiming to challenge the prevailing terrestrial narrative in archaeology, which has impeded the interpretive potential for comprehending maritime societies throughout prehistory.

E-suite for Soldiers based on Photovoltaic Cells

We are urgently attempting to power the technology that surround us with clean energy. However, It never occurs to me to make bulletproof coats intelligent. In addition to a basic Kevlar vest, soldiers who defend our nation should receive an E-Uniform that operates on sustainable energy. This study article suggests such a uniform. The attire improves a soldier's ability to withstand extremes of temperature in adverse weather situations. It has a solar panel installed that charges the battery. The necessary heating and cooling effect is provided by the mounted Peltier plate. Additionally, the soldier's clothing incorporates GPS to track their precise location and GSM to make touch with them. Additionally, it has a metal detector to locate metal objects like bombs and is naturally camouflaged. Keywords—Kevlar, Peltier plate, GPS, GSM, Metal Detector,Camouflage..

Features of the Stress–Strain State of 3D Metal Objects Produced by Additive Microplasma Deposition of the Powder of a Fe–Cr–Ni–B–Si System

Features of the Stress–Strain State of 3D Metal Objects Produced by Additive Microplasma Deposition of the Powder of a Fe–Cr–Ni–B–Si System

Extended-Aperture Shape Measurements Using Spatially Partially Coherent Illumination (ExASPICE).

We have recently demonstrated that the 3D shape of micro-parts can be measured using LED illumination based on speckle contrast evaluation in the recently developed SPICE profilometry (shape measurements based on imaging with spatially partially coherent illumination). The main advantage of SPICE is its improved robustness and measurement speed compared to confocal or white light interferometry. The limited spatial coherence of the LED illumination is used for depth discrimination. An electrically tunable lens in a 4f-configuration is used for fast depth scanning without mechanically moving parts. The approach is efficient, takes less than a second to capture required images, is eye-safe and offers a depth of focus of a few millimeters. However, SPICE's main limitation is its assumption of a small illumination aperture. Such a small illumination aperture affects the axial scan resolution, which dominates the measurement uncertainty. In this paper, we propose a novel method to overcome the aperture angle limitation of SPICE by illuminating the object from different directions with several independent LED sources. This approach reduces the full width at half maximum of the contrast envelope to one-eighth, resulting in a twofold improvement in measurement accuracy. As a proof of concept, shape measurements of various metal objects are presented.

Online elasticity estimation and material sorting using standard robot grippers

Stiffness or elasticity estimation of everyday objects using robot grippers is highly desired for object recognition or classification in application areas like food handling and single-stream object sorting. However, standard robot grippers are not designed for material recognition. We experimentally evaluated the accuracy with which material properties can be estimated through object compression by two standard parallel jaw grippers and a force/torque sensor mounted at the robot wrist, with a professional biaxial compression device used as reference. Gripper effort versus position curves were obtained and transformed into stress/strain curves. The modulus of elasticity was estimated at different strain points and the effect of multiple compression cycles (precycling), compression speed, and the gripper surface area on estimation was studied. Viscoelasticity was estimated using the energy absorbed in a compression/decompression cycle, the Kelvin-Voigt, and Hunt-Crossley models. We found that (1) slower compression speeds improved elasticity estimation, while precycling or surface area did not; (2) the robot grippers, even after calibration, were found to have a limited capability of delivering accurate estimates of absolute values of Young’s modulus and viscoelasticity; (3) relative ordering of material characteristics was largely consistent across different grippers; (4) despite the nonlinear characteristics of deformable objects, fitting linear stress/strain approximations led to more stable results than local estimates of Young’s modulus; and (5) the Hunt-Crossley model worked best to estimate viscoelasticity, from a single object compression. A two-dimensional space formed by elasticity and viscoelasticity estimates obtained from a single grasp is advantageous for the discrimination of the object material properties. We demonstrated the applicability of our findings in a mock single-stream recycling scenario, where plastic, paper, and metal objects were correctly separated from a single grasp, even when compressed at different locations on the object. The data and code are publicly available.

Image quality assessment of fractures of metallic objects

The problem of calculating a quantitative quality assessment of digital images of metal object fractures recorded by a camera or a digital microscope is considered. Quality assessment is performed when the reference images are absent. The paper presents an approach based on calculation of local estimates followed by analysis of their distribution. Several variants for calculation of local estimates have been studied. Those whose distribution is unimodal were selected. It is shown that the average of local estimates is an acceptable general characteristic of image quality if they have a normal (Gaussian) distribution. In this case, the average is one of its parameters. Otherwise, the parameters of the Weibull distribution can serve as more accurate quantitative characteristics of image quality in general. The proposed approach divides more objectively the set of the analyzed images into two groups those with satisfactory or unsatisfactory quality for performing expert studies using images. Examples of the quality assessment of different object images recorded at different resolutions are presented.

The Production of Three-Dimensional Metal Objects Using Oscillatory-Strain-Assisted Fine Wire Shaping and Joining.

Material shaping and joining are the two fundamental processes that lie at the core of many forms of metal manufacturing techniques, including additive manufacturing. Current metal additive manufacturing processes such as laser/e-beam powder bed fusion and Directed Energy Deposition predominantly use heat and subsequent melt-fusion and solidification to achieve shaping and joining. The energy efficiency of these processes is severely limited due to energy conversion losses before energy is delivered at the point of melt-fusion for shaping and joining, and due to losses through heat transfer to the surrounding environment. This manuscript demonstrates that by using the physical phenomenon of lowered yield stress of metals and enhanced diffusion in the presence of low amplitude high frequency oscillatory strain, metal shaping and joining can be performed in an energy-efficient way. The two performed simultaneously enable a metal additive manufacturing process, namely Resonance-Assisted Deposition (RAD), that has several unique capabilities, like the ability to print net-shape components from hard-to-weld alloys like Al6061 and the ability to print components with a very high aspect ratio. In this study, we show this process's capabilities by printing solid components using aluminum-based metal alloys.

3D scanning of daguerreotypes

Daguerreotypes are historical photographic images made on mirror-like metallic plates. These are heritage objects whose shape cannot be measured with invasive techniques, like contact probes, but the high reflectivity of their surfaces makes the use of non-invasive, 3D-measuring optical techniques challenging. Moreover, the dark areas resulting from their degradation produce a very high contrast, which add extra difficulties to their measurement. In the last few years, several strategies have been developed to overcome the limitations of optical techniques when measuring reflective metallic surfaces. Many of these solutions are not applicable to the study of cultural heritage artifacts, as they are invasive. We attempted the use of conoscopic holography in a 3D-scanning system using a double-exposure strategy. This is a promising option for 3D measuring of daguerreotypes, as we experimentally demonstrated in this work. We present the results obtained from the analyses of two 19th-century daguerreotypes with different superficial conditions. The double-exposure allowed us to obtain high-quality data from the entire object surface. This enabled the measurement of micro-scale details related to the manufacturing process and/or to the corrosion deposits. The proposed methodology can be exploited to monitor the overall health of highly reflective metallic objects but also the outcomes of some conservation treatments, such as cleaning.

Feasibility Examination of the Field Multi-focal Metallography Method (FMM) for Characterisation of Metallic Marine Artefacts

Field multi-focal metallography (FMM) is a development of field metallographic replication (FMR). It is an innovative minimally destructive technique that facilitates high-resolution metallographic observations of metallic object surfaces, regardless of their orientation to the optical axis of the microscope. Several artefacts retrieved during underwater excavations (a bronze powder chamber, a stud-link anchor chain, a winch, a heart-shaped shackle, a deadeye strap with a futtock plate, and an iron stud-link chain controller) were examined. The FMM results were compared with conventional metallography, where the sampling process inflicts substantial damage to the item. This FMM trial produced results of comparable quality to conventional metallography for both the bronze and the ferrous objects. It revealed the microstructure of the archaeological objects with minimal damage. The FMM method was shown to be a suitable tool for the study of ancient metal objects retrieved from shipwrecks.

Frequency of oesophageal foreign bodies ingested by children presenting to the ENT department.

Objective: To determine the frequencies of different esophageal foreign bodies ingested by children presenting to Ayub Teaching Hospital Abbottabad. Study Design: Cross-sectional study. Setting: Department of Otorhinolaryngology, Ayub Teaching Hospital Abbottabad. Period: 2nd July 2020 to 31st December 2022. Material & Methods: Following the application of inclusion and exclusion criteria, a total of 168 patients, aged between 6 months and 11 years, presenting with suspected esophageal foreign bodies, were included in the study after obtaining written consent. Socio-demographic information, clinical history, and symptoms were carefully recorded. Diagnostic procedures included neck X-rays, extended to the chest, and abdominal X-rays as necessary. Rigid esophagoscopy, performed under general anesthesia, was utilized to confirm and remove foreign bodies. Subsequently, the nature and type of the extracted foreign bodies were identified and documented using a standardized pro forma. Results: The mean age of the patients was 5.63 ± 3.097, ranging from 1 to 11 years. Regarding the gender distribution, 105 (62.5%) were male, and 63 (37.5%) were female. When considering the types of foreign bodies, 129 (76.8%) presented with coins, 12 (7.1%) with metallic objects, 7 (4.2%) with battery cells, and 9 (5.4%) with fruit seeds. Additionally, there were a few cases of chicken bones, fish bones, and safety pins, accounting for 9 (5.4%) in the category of other foreign bodies. Conclusion: This study underscores the frequent occurrence of esophageal foreign body ingestion in young children, particularly males under the age of 5, with coins identified as the predominant culprits.

Etiology, pathogenesis, and management of angiosarcoma associated with implants and foreign body: Clinical cases and research updates.

Angiosarcomas are rare and highly malignant soft tissue sarcomas originating from endothelial cells lining the lymphatic or vascular system. While they predominantly emerge from (sub)cutaneous regions, occurrences have been reported throughout the body. The etiology of angiosarcoma remains elusive in most clinical cases. Nevertheless, several prognosis risk factors play a pivotal role, including chronic lymphedema, therapeutic irradiation, environmental carcinogens, familial syndromes, and the presence of foreign materials like metallic objects and biomedical implants. Despite evidence implicating retained foreign material in angiosarcoma development, understanding its prognosis and pathogenesis remains limited. The pathogenesis of angiosarcoma appears to involve a complex interplay of chronic inflammation, tissue remodeling, and genetic factors that create a conducive microenvironment for malignant transformation. Management of these sarcomas remains challenging due to their infiltrative nature owing to the high chance of metastasis and local recurrence. The primary treatment modalities currently include surgery, radiotherapy, and chemotherapy, but recent advances in targeted immunotherapy and gene therapy hold promise for more effective approaches. This comprehensive review delves into the potential etiological and pathogenic roles of foreign materials, such as metallic objects, biomedical implants, and biomaterials, in the development of angiosarcoma. Further research into the underlying molecular mechanisms could provide valuable insights for tailored management and developing novel targeted therapeutic strategies.

Metal-for-Amber in the European Bronze Age

Abstract Baltic amber is often considered the principal Scandinavian commodity exchanged for metal from ore-rich regions in Europe. If correct, this may explain the astonishing metal wealth of the Nordic Bronze Age and the modest social consumption of amber locally. The hypothesis of a metal-for-amber principle behind the trade is here for the first time assessed on scales from micro to macro. Amber finds were charted across Europe, and the result was then compared to evidence for regular shifts in copper ore preferences/availability, as found in the systematically changing isotopic/elemental composition of Nordic metal objects in c. 2100–1200 BC. Comparisons indicate that amber and metal followed similar spatiotemporal trajectories with major reorganizations at the turn from the Early to the Middle Bronze Age. Shifts in amber distribution correlate with the geography of metal sources used in both periods and flows of metal to Scandinavia and amber to Europe appear to be contingent even in subperiods. Major European amber tracks – and the crossroads hubs controlling them – were identified for the transfer of goods, yet again revealing major changes at the transition to the Middle Bronze Age. The social roles and meanings of amber among Nordic communities were likewise examined, suggesting that bearers of amber played a role in exercising social control of this resource. It is concluded that amber almost certainly was exchanged for metal.

FABRICATION OF AUTOMATIC MOTORIZED BENCH VICE

A vice is nothing but a holder which has two holding points at each ends and this holding points help the work piece to stay in place so that the work car be done on the work piece. Now here one of the jaws on the vice is fixed and do not move and the other jaw that is placed in opposite moves so that we can adjust the vise according to the work piece design. So basically the first jaw of the vice helps to hold the work piece in the place and the second jaw can be used to tighten or loosen according to the shape of the work piece. So this is how the basic bench vice works. So the vise can be used for doing many works on it such as to shape a metal object, to make keys, also to cut the object etc.. Like this there are many ways for which we can use the bench vise. Now the paper basically relates to the vises and the scope of improving the working of Bench vise with the help of using a DC motor which helps in the movement of the jaws through the dc motor. Now the main objective of this paper is to make a bench vise which can be operated without any man power and use dc Motor to clamp the work piece so that the work can be done on it. The power to the movable jaw is supplied by the dc motor so that the work can be done on the work piece of any size and shape. We have also tested the vise with various work Pieces just to verify so that it can hold properly while the work is done Key Words: Vice, DC Motor, Clamp, Workpiece

High Dynamic Range Image Reconstruction from Saturated Images of Metallic Objects.

This study considers a method for reconstructing a high dynamic range (HDR) original image from a single saturated low dynamic range (LDR) image of metallic objects. A deep neural network approach was adopted for the direct mapping of an 8-bit LDR image to HDR. An HDR image database was first constructed using a large number of various metallic objects with different shapes. Each captured HDR image was clipped to create a set of 8-bit LDR images. All pairs of HDR and LDR images were used to train and test the network. Subsequently, a convolutional neural network (CNN) was designed in the form of a deep U-Net-like architecture. The network consisted of an encoder, a decoder, and a skip connection to maintain high image resolution. The CNN algorithm was constructed using the learning functions in MATLAB. The entire network consisted of 32 layers and 85,900 learnable parameters. The performance of the proposed method was examined in experiments using a test image set. The proposed method was also compared with other methods and confirmed to be significantly superior in terms of reconstruction accuracy, histogram fitting, and psychological evaluation.