Academic literature on the topic 'Multi-Camera Rigs'

In this paper, we present a novel approach to imaging a panoramic (360°) environment and computing its dense depth map. Our approach adopts a multi-baseline stereo strategy using a set of multi-perspective panoramas where large baseline lengths are available. We design two image acquisition rigs for capturing such multi-perspective panoramas. The first one is composed of two parallel stereo cameras. By rotating the rig about a vertical axis, we generate four multi-perspective panoramas by resampling the regular perspective images captured by the stereo cameras. Then a depth map is estimated from the four multi-perspective panoramas and an original perspective image using a multi-baseline matching technique with different types of epipolar constraints. The second one is composed of a single camera and two mirrors. By rotating the rig, we acquire a spatio-temporal volume that is made up of the sequential images captured by the camera. Then we estimate a depth map by extracting trajectories from the spatio-temporal volume by using a multi-baseline stereo technique by considering occlusions. We can consider both rotating rigs as a single rotating camera with a very large field of view (FOV), that offers a large baseline length in depth estimation. In addition, compared with a previous approach using two multi-perspective panoramas from a single rotating camera, our approach can reduce matching errors due to image noise, repeated patterns, and occlusions by multi-baseline stereo techniques. Experimental results using both synthetic and real images show that our approach produces high quality panoramic 3D reconstruction.

The article deals with certain medico-legal aspects of trauma in the salon of bus as one of the types of road traffic accidents with a large number of dead and injured. Are shown the typical causes of such incidents and the nature of the victims injury. Was developed and proposed a modern approach to optimization of expert research in case of appearance a large number of victims in the bus. Circumstances of injury in case of personal injury people in the bus are very diverse:− rollover of the bus when transporting a large number of people while driving;− bus falling from height;− a massive collision with a fixed roadside objects; − collision with other vehicles; among the latter is the most fatal bus collision with a moving train.Naturally, in these cases, the massive injuries have affected depends on the intensity of injury to passengers in the bus, and the mechanism of damage is determined by the specific form of an accident involving a bus. In such cases, the experts faced, usually with mechanical trauma inside the cabin, and mixed types of injuries passengers (e.g. in case of fire). For in-car trauma characterized by formation damage from the following mechanisms:− shock bodies on the inner part of the interior (interior);− injuries from the shards of broken glass.Basically, the nature of injury is determined by the structural features of the bus, the presence of foreign objects, the location of the victims. If the vehicle rolls over, the occupants people are numerous additional impact. Formed characteristic for the driver damage to the hands, fractures of the sternum fractures of the hips, legs and feet. For passengers is characteristic fractures of the lower limbs, bruised head wounds, fractures and dislocations of the cervical spine when using the seat belts − stripe-like bruises and abrasions ofthe chest and abdomen, broken ribs, collarbone, sternum, in the projection of the belts. Shards of broken glass caused by the multiple linear abrasions and (or) surface or deep cut wounds mainly in the face and upper extremities. In the case of deformation of the bus body can be compression of the bodies are formed by damage to several areas, primarily the chest, abdomen, extremities, accompanied by multiple bilateral rib fractures, ruptures of internal organs. If in the future there is a fire or explosion of the vehicle, the nature of thedamage detected on the bodies will correspond to the combined injury.In cases of injuries in the bus to work with the bodies of the victims begins at the scene. Thus, the Protocol of inspection of the scene and of the corpse in the first place should reflect the data about the mutual position of bodies and (or) their fragments relative to the vehicle and other parts, the distance between them; the condition of clothing, odors from it, the presence of different overlays, damage; contamination of the skin; localization and nature of the injuries on the bodies, the presence of deformations of its individualparts; the presence of traces of biological origin on the vehicle in comparison with the nature of the deformation (damage) of the body.Be sure to note the results of the inspection of the road where there was a traffic accident, a bus traces of blood, and fragments of various things, etc. Despite the small percentage of bus injured in world General statistics of fatal injuries, it presents certain difficulties in planning, organization, execution and coordination of forensic work on multi-step liquidation of medical consequences of the accident, usually associated with a large number of victims, gross impact of factors affecting on the bodies of the victims, the need to quickly address some specific issues: establishing at autopsy pathological symptoms that indicate the status of the health of drivers in the period priorto the tragic event; the existence of facts pointing to the use of intoxicating and medicinal substances that depress the nervous system and many others), early identification of all victims. According to the results of the analysis made it impossible to offer modern, optimal, evidence-informed, and until only itremains to be reliable in practice the system approach to the organizational model of forensic activities, while ensuring the interests of the investigation of an accident involving a bus and a large number of victims:1. The preliminary stage of organization expert services. It can conditionally enough be divided into 2 phases:− advance (pre-) phase;− the immediate phase.To the basic questions of the early phases include: early development, coordination and approval of the optimal legislative and other regulatory framework; preliminary methodological, administrative and organizational, theoretical-practical, logistical, software and applied training; exercise reasonable estimates of projected short and long term needs and costs with regard to the peculiarities specified by the tragic events; creation, storage, use and replenishment of the trust reserves, logistical and financial resources areinviolable, is intended solely for use in such emergencies. It also includes the creation, maintenance and continuous improvement of a Single centralized situation center on a temporary or permanent basis, with a good system of departmental and interdepartmental cooperation, primarily containing a - operational information-Supervisory and analytical center for the collection, processing, storage, information exchange and joint action with the threat, occurrence and prevention of emergencies with a large number of victims.Immediately with the receipt of the news of the accident involving a bus and a large number of victims for forensic services begin immediate phase, the main elements of which include:− prompt notification and collection of employees and expert institutions;− an emergency conference call to discuss the organizational, theoretical and practical questions and short specialized trainingon occupational safety, including use of personal protective equipment depending on the nature of the accident and actions are potentially dangerous to health and life of employees and expert institutions factors.All plans of measures are necessarily coordinated and agreed with appropriate representatives of structures of fast reaction, especially when conducting urgent investigative actions in the emergency areas, primarily the inspection of the scene. 2. The inspection of the crime scene it is advisable to start with a preliminary review («intelligence»), which finally determined the necessity of application of those or other technical means, and the number of specialists who will participate in the inspection.The static phase of scene examination with the participation of forensic doctors is accompanied by clear mapping; mapping, photo - and video fixing of vehicle, various objects; it is noted the exact relative positions of the bus (its parts) and discovered the corpses, fragments of human remains and other biological material. During dynamic examination of the scene produce a detailed external examination of the human remains, their fragments, biological material, perform primary medical sorting, their careful packaging,clear detailed marking. Then performed the proper loading, transportation and unloading. In case of need in a temporary Deposit of biological material, can be used in railway wagons refrigerators, refrigerated trailers, mobile camera with a refrigeration unit, and in the absence or lack of volume for the total number of remains and the biomaterial deploys heat-resistant boxes, fit the space with the use of outdoor mobile air conditioning systems, large amounts of ice obtained from specialized industrial ice makers, etc., which is especially important for braking processes of rotting corpses, their fragments and biomaterial in the warm season.3. After the initial registration and a secondary sort examine corpses, their fragments and biological material collection for postmortem identification of significant information, determine the cause of death, nature, mechanism and prescription of formation damage and address other special issues. At this stage also produce the identification of fragmented body parts and (or) tissues that or another body. In expert identification work on the fragments of human remains or biological material, preference is given to genetic research providing highly accurate results. Depending on the extent of influence of damaging factors on the bodies of the victims and their degree of preservation, only after the completion of the necessary is judicial-medical research with a full range of fence material for additional research, producing restoration of the exterior, embalming, sanitary and cosmetic processing of human remains and give them to relatives (relatives, authorized representatives, etc.) for burial. 4. Issued the final results of examinations; establishes data that may be useful for later investigative and judicial actions aimed at gathering and verification of evidence in a criminal case.5. The penultimate stage consists of conducting sanitary-and-hygienic, treatment-and-prophylactic, rehabilitation (including a full psychological) of interventions for physical and mental health of employees and expert institutions involved in this work.6. After the conclusion of the criminal proceedings in general, with the official opening of data access, it is advisable to analyze the material, and publish the relevant data in the scientific literature, with the goal of widespread study and use of gained experience.CONCLUSIONS.1. Research platform forensic activities in cases of accidents involving buses and a large number of victims to date have not been developed.2. The effectiveness of forensic medical groups in this situation is in direct proportion to the degree of readiness for quick response and timely quality completion of tasks.3. Based on this, very urgent is the development of modern optimal evidence-based systemic approach to the organizational model of forensic activities in the presence of a large number of injured persons in the bus; the solution to this problem and sent the above recommendations.4. The recommendations, in principle, can be applied not only in cases of injuries in the bus, but also to similar situations in which there is a massive injury and loss of life.5. It is necessary to continue scientific and practical research aimed at improving this algorithm works experts.

Abstract: The global turn is central to the study of Europe’s many migration histories—outwards, inwards, and internal—and encompasses transatlantic, imperial and post-imperial, and other global arenas. Benefitting from a wealth of pathbreaking scholarship that often focuses on macro-level histories, this article advocates zooming in on individual interpretations and experiences. By doing so, it argues, historians can open up nuanced perspectives that risk becoming submerged in studies where, rather paradoxically, actual migrants are displaced by an emphasis on overarching migration phenomena. Taking the late-modern era as its focus, it traces the global dimensions of two lives spanning almost two centuries to open out broader questions, not least about race and ethnicity. Jacob Riis (1849-1914) and Gérald Bloncourt (1926-2018) were both leading documentary photographers who shared a deep commitment to social reform and the amelioration of working-class conditions. Each recorded migration histories on camera and in writing, thereby enabling an analysis of multi-media representations emanating from the same source. That both were of migration backgrounds themselves—Riis having moved from Denmark to the United States and Bloncourt from Haiti to France—renders the images and texts they created particularly resonant. Their own origins and mobile lives proved crucial to their interpretations of the wider flows of people that have connected Europe with different global settings—and continue to do so today.

The estimation of motion of multi-camera systems is one of the most important tasks in computer vision research. Recently, some issues have been raised about general camera models and multi-camera systems. Using many cameras as a single camera is studied [60], and the epipolar geometry constraints of general camera models is theoretically derived. Methods for calibration, including a self-calibration method for general camera models, are studied [78, 62]. Multi-camera systems are an example of practically implementable general camera models and they are widely used in many applications nowadays because of both the low cost of digital charge-coupled device (CCD) cameras and the high resolution of multiple images from the wide field of views. To our knowledge, no research has been conducted on the relative motion of multi-camera systems with non-overlapping views to obtain a geometrically optimal solution. ¶ In this thesis, we solve the camera motion problem for multi-camera systems by using linear methods and convex optimization techniques, and we make five substantial and original contributions to the field of computer vision. First, we focus on the problem of translational motion of omnidirectional cameras, which are multi-camera systems, and present a constrained minimization method to obtain robust estimation results. Given known rotation, we show that bilinear and trilinear relations can be used to build a system of linear equations, and singular value decomposition (SVD) is used to solve the equations. Second, we present a linear method that estimates the relative motion of generalized cameras, in particular, in the case of non-overlapping views. We also present four types of generalized cameras, which can be solvable using our proposed, modified SVD method. This is the first study finding linear relations for certain types of generalized cameras and performing experiments using our proposed linear method. Third, we present a linear 6-point method (5 points from the same camera and 1 point from another camera) that estimates the relative motion of multi-camera systems, where cameras have no overlapping views. In addition, we discuss the theoretical and geometric analyses of multi-camera systems as well as certain critical configurations where the scale of translation cannot be determined. Fourth, we develop a global solution under an L∞ norm error for the relative motion problem of multi-camera systems using second-order cone programming. Finally, we present a fast searching method to obtain a global solution under an L∞ norm error for the relative motion problem of multi-camera systems, with non-overlapping views, using a branch-and-bound algorithm and linear programming (LP). By testing the feasibility of LP at the earlier stage, we reduced the time of computation of solving LP.¶ We tested our proposed methods by performing experiments with synthetic and real data. The Ladybug2 camera, for example, was used in the experiment on estimation of the translation of omnidirectional cameras and in the estimation of the relative motion of non-overlapping multi-camera systems. These experiments showed that a global solution using L∞ to estimate the relative motion of multi-camera systems could be achieved.

The estimation of motion of multi-camera systems is one of the most important tasks in computer vision research. Recently, some issues have been raised about general camera models and multi-camera systems. Using many cameras as a single camera is studied [60], and the epipolar geometry constraints of general camera models is theoretically derived. Methods for calibration, including a self-calibration method for general camera models, are studied [78, 62]. Multi-camera systems are an example of practically implementable general camera models and they are widely used in many applications nowadays because of both the low cost of digital charge-coupled device (CCD) cameras and the high resolution of multiple images from the wide field of views. To our knowledge, no research has been conducted on the relative motion of multi-camera systems with non-overlapping views to obtain a geometrically optimal solution. ¶ In this thesis, we solve the camera motion problem for multi-camera systems by using linear methods and convex optimization techniques, and we make five substantial and original contributions to the field of computer vision. ...

Abstract Surface data measurement and analysis are an established mean of detecting drillstring low-frequency torsional vibration or stick-slip. The industry has also developed models that link surface torque and downhole drill bit rotational speed. Cameras provide an alternative noninvasive approach to existing wired/wireless sensors used to gather such surface data. The results of a preliminary field assessment of drilling dynamics utilizing camera-based drillstring monitoring are presented in this work. Detection and timing of events from the video are performed using computer vision techniques and object detection algorithms. A real-time interest point tracker utilizing homography estimation and sparse optical flow point tracking is deployed. We use a fully convolutional deep neural network trained to detect interest points and compute their accompanying descriptors. The detected points and descriptors are matched across video sequences and used for drillstring rotation detection and speed estimation. When the drillstring's vibration is invisible to the naked eye, the point tracking algorithm is preceded with a motion amplification function based on another deep convolutional neural network. We have clearly demonstrated the potential of camera-based noninvasive approaches to surface drillstring dynamics data acquisition and analysis. Through the application of real-time object detection algorithms on rig video feed, surface events were detected and timed. We were also able to estimate drillstring rotary speed and motion profile. Torsional drillstring modes can be identified and correlated with drilling parameters and bottomhole assembly design. A novel vibration array sensing approach based on a multi-point tracking algorithm is also proposed. A vibration threshold setting was utilized to enable an additional motion amplification function providing seamless assessment for multi-scale vibration measurement. Cameras were typically devices to acquire images/videos for offline automated assessment (recently) or online manual monitoring (mainly), this work has shown how fog/edge computing makes it possible for these cameras to be "conscious" and "intelligent," hence play a critical role in automation/digitalization of drilling rigs. We showcase their preliminary application as drilling dynamics and rig operations sensors in this work. Cameras are an ideal sensor for a drilling environment since they can be installed anywhere on a rig to perform large-scale live video analytics on drilling processes.

Abstract The COVID-19 pandemic posed a real challenge to business continuity of our safety assurance programs, incident investigations and training of young engineers which are traditionally conducted through physical rig site visits. The measures taken to control the spread of the COVID-19 virus meant that physical visits to the rig sites were restricted and during certain times completely stopped. The consequence of such measure meant that the safety assurance program was heavily impacted as the weekly leadership site visits were suspended. This posed a risk of a potential increase in safety incidents. Moreover, only safety critical personnel were allowed at the rig sites meaning that all trainee drilling supervisors and engineers were not allowed to visit the rig sites as part of the COVID-19 control measures. This in turn directly impacted the training program of our young engineers and trainee drilling supervisors for the entire COVID-19 pandemic period – Not Good! The potential risk of an increase in safety incidents due to lack of safety assurance was too great a cost to accept. Therefore, the drilling team started to think differently. A multi-disciplinary brainstorming workshop involving technology providers in the digital space was conducted to discuss possible ways of conducting rig site visit virtually. During this workshop, augmented reality via use of the wearable camera was flagged as a technology ready solution for our challenge. Several subsequent sessions were conducted with ADNOC Onshore IT team to build a business case for the wearable camera. The wearable camera is an intrinsically safe Zone 1 certified fully rugged head-mounted device made for harsh environments. The high-resolution micro display fits just below the user's line of sight and views like a 7" tablet. A business case was put forward and approved to conduct a proof of concept (PoC) to specifically test the ability to conduct remote rig visits, investigations and training programs. The PoC was successfully completed and allowed the team to conduct remote rig visits, audits, investigations and training programs with the "touch and feel" of being at the rig site – a paradigm shift in the way we run our business.

The powered flight of bats is unique in nature because of the agility that it allows them to achieve in comparison to other flying animals of equivalent size. One example of this is a bat’s ability to take off with no initial freestream velocity and transition to cruising flight over the duration of relatively few wing beat cycles. Bat’s wings are highly complex and have 20+ degrees of freedom (DOFS) per wing. Adjustments to several of these DOFS occur to allow for quick transition to cruising flight. In order to capture this transition in wing motion, video of Great Himalayan Leaf-Nosed Bats (Hipposideros Armiger) was captured over a period that included both take off and cruising flight. Images captured using a multi-camera setup, containing three rings of 10 RGB cameras each, were used in conjunction with triangulation techniques to capture the 3D coordinates of marker points on the wing. This setup eliminated the point dropout that can occur due to occlusion in traditional 2 camera systems due to its 360 degree coverage. Furthermore, the redundancy caused by collecting 3 or more 2D marker point projections from some of the 10 cameras per ring improved accuracy of the 3D coordinates. In order to capture the transition in wing kinematics, changes in flap amplitude, velocity, and frequency, were recorded. The data suggests that this species of bat utilize a change in flap amplitude as the primary means to transition from takeoff to cruising flight while keeping other parameters such as angle of attack and flap frequency constant.

Abstract A prolific gas producer in Sarawak waters was shut-in and idle due to a tubing leak resulting in a significant decline in the total hub production. The well remained idle and required immediate remedial action to meet the contractual sales target. Hence, an expandable tubing patch was proposed to isolate the leak and reactivate the well faster. This paper presents data gathered to identify leak location, tubing patch design, and installation using real-time coil tubing. Several logging surveys were performed to detect leak depth including caliper log, leak detection log (LDL), and downhole camera run; since no pressure build-up was observed post bleed-off tubing and casing, while SCSSV was in closed-state. Running caliper log could not indicate severe metal loss of 7-inch tubing, hypothesizing that the leak could be of a smaller dimension. Therefore, LDL was conducted, indicating temperature gradient and acoustic energy changes at a single depth location of 247 ft.THF, above SCSSV. Utilizing the leak depth marker from acoustic log, a downhole camera was staged to verify geometry of tubing leak. Root cause failure analysis (RCFA) was carried out for this tubing anomaly using diagnostics data to determine the possibility of UHP-17Cr-110 tubing failure. The likelihood of tubing failure is attributed to two main causes namely oxygen corrosion cracking and stress corrosion cracking. Based on RCFA outcome, Hastelloy C276, a nickel-molybdenum-chromium superalloy with the addition of tungsten was selected for the patch material, which is V0 rated, internal gas-tight qualification for temperatures up to 150 degrees Celsius and 5,000 psi. Moreover, this patch material satisfies the well conditions at approximately 20% CO2, 200 ppm H2S, 1000 mg/L salinity, and varying Hg concentrations from 800-2,000 ug/Nm3. The design of patch has been improved by adding AFLAS elastomer for the whole exterior of patch to eliminate contacts between the two metals: reducing the risk of galvanic corrosion. Real-time coiled tubing application was selected for setting the patch to ensure accurate depth-sensing control. Additionally, patch is a rig less intervention technique that will not disrupt the production from the existing wells sharing the same drilling platform. Generally, for high-rate gas wells, economic indicators seem lucrative with tubing patch application, where the payout can be achieved within a month of continuous production. The first step in ensuring the success of tubing patch is by running right diagnostics tools such as leak detection logging and downhole camera run, since multi-finger caliper analysis alone would not locate the leak depth and the leak geometry precisely. Valid design inputs are quintessential for the fitting recommendation of tubing patch design which includes accurate reservoir and fluid properties to ensure sustainability of the expandable tubing patch application.