Browse Topic: Visibility
ABSTRACT What does “exposure to risk” mean? How can acquisition programs get early warning of risk exposure? How is risk exposure related to the root causes and causal mechanisms of adverse program outcomes? How does risk early warning inform risk management? How is risk exposure related to the tradeoffs made between risk versus potential rewards? What technical and management contract data reporting requirements provide evidence of risk exposure, and how can risk leading indicators be computed? How can standard technical and management contract data reporting requirements be used to improve visibility into risk exposure? How can the magnitude of risk exposure be estimated? How does risk early warning complement traditional technical, cost and schedule risk assessment? How do risk early warning methods relate to typical proposal requirements and evaluation criteria? How are risk leading indicators related to system development leading indicators? How can risk early warning methods be
Most humans rely heavily on our visual abilities to function in the world—we are optically oriented. In the broadest sense, “optics” refers to the study of sight and light. At its foundation, Radiant’s business is all about optics: measuring light and the properties of light in relation to the human eye. Photometry is the science of light according to our visual perception. Colorimetry is the science of color: how our eyes interpret different wavelengths of light
Ergonomics plays an important role in automobile design to achieve optimal compatibility between occupants and vehicle components. The overall goal is to ensure that the vehicle design accommodates the target customer group, who come in varied sizes, preferences and tastes. Headroom is one such metric that not only influences accommodation rate but also conveys a visual perception on how spacious the vehicle is. An adequate headroom is necessary for a good seating comfort and a relaxed driving experience. Headroom is intensely discussed in magazine tests and one of the key deciding factors in purchasing a car. SAE J1100 defines a set of measurements and standard procedures for motor vehicle dimensions. H61, W27, W35, H35 and W38 are some of the standard dimensions that relate to headroom and head clearances. While developing the vehicle architecture in the early design phase, it is customary to specify targets for various ergonomic attributes and arrive at the above-mentioned
This SAE Recommended Practice defines key terms used in the description and analysis of video based driver eye glance behavior, as well as guidance in the analysis of that data. The information provided in this practiced is intended to provide consistency for terms, definitions, and analysis techniques. This practice is to be used in laboratory, driving simulator, and on-road evaluations of how people drive, with particular emphasis on evaluating Driver Vehicle Interfaces (DVIs; e.g., in-vehicle multimedia systems, controls and displays). In terms of how such data are reduced, this version only concerns manual video-based techniques. However, even in its current form, the practice should be useful for describing the performance of automated sensors (eye trackers) and automated reduction (computer vision
A new spatial calibration procedure has been introduced for infrared optical systems developed for cases where camera systems are required to be focused at distances beyond 100 meters. Army Combat Capabilities Development Command Armaments Center, Picatinny Arsenal, NJ All commercially available camera systems have lenses (and internal geometries) that cannot perfectly refract light waves and refocus them onto a two-dimensional (2D) image sensor. This means that all digital images contain elements of distortion and thus are not a true representation of the real world. Expensive high-fidelity lenses may have little measurable distortion, but if sufficient distortion is present, it will adversely affect photogrammetric measurements made from the images produced by these systems. This is true regardless of the type of camera system, whether it be a daylight camera, infrared (IR) camera, or camera sensitive to another part of the electromagnetic spectrum. The most common examples of large
Blind spots created by the driver-side B-pillar impair the ability of the driver to assess their surroundings accurately, significantly contributing to the frequency and severity of vehicular accidents. Vehicle manufacturers cannot readily eliminate the B-pillar due to regulatory guidelines intended to protect vehicular occupants in the event of side collisions and rollover incidents. Furthermore, assistance implements utilized to counteract the adverse effects of blind spots remain ineffective due to technological limitations and optical impediments. This paper introduces mechanisms to quantify the obstruction caused by the B-pillar when the head of the driver is facing forward and turning 90°, typical of an over-the-shoulder blind spot check. It uses the metrics developed to demonstrate the relationship between B-pillar width and the obstruction angle. The paper then creates a methodology to determine the movement required of the driver to eliminate blind spots. Ultimately, this
Thermal control coatings, i.e. coatings with different visible versus infrared emission, have been used by NASA on the Orbiter and Hubble Telescope to reflect sunlight, while allowing heat rejection via infrared emission. However, these coatings absorb at least 6 percent of the Sun’s irradiant power, limiting the minimum temperature that can be reached to about 200 K. NASA needs better solar reflectors to keep cryogenic fuel and oxidizers cold enough to be maintained passively in deep space for future missions
Advanced driver assistance systems rely on external sensors that encompass the vehicle. The reliability of such systems can be compromised by adverse weather, with performance hindered by both direct impingement on sensors and spray suspended between the vehicle and potential obstacles. The transportation of road spray is known to be an unsteady phenomenon, driven by the turbulent structures that characterise automotive flow fields. Further understanding of this unsteadiness is a key aspect in the development of robust sensor implementations. This paper outlines an experimental method used to analyse the spray ejected by an automotive body, presented through a study of a simplified vehicle model with interchangeable rear-end geometries. Particles are illuminated by laser light sheets as they pass through measurement planes downstream of the vehicle, facilitating imaging of the instantaneous structure of the spray. The tested configurations produce minor changes to the flow field, the
Digital shearography has many advantages, such as full-field, non-contact, high sensitivity, and good robustness. It was widely used to measure the deformation and strain of materials, also to the application of nondestructive testing (NDT). However, most digital sherography applications can only work in one field of view per measurement, and some small defects may not be detected as a result. Multiple measurements of different fields of view are needed to solve this issue, which will increase the measurement time and cost. The difficulty in performing multiple measurements may also increase for cases where the loading is not repeatable. Therefore, a system capable of measuring dual fields of view at the same time is necessary. The carrier frequency spatial phase shift method may be a good candidate to reach this goal because it can simultaneously record phase information of multiple images, e.g. two speckle interferograms with different fields of view. It then obtains the phase
As new headlight technologies begin to take hold in vehicular forward lighting systems and they become more commonplace on vehicles, new frameworks for evaluating the performance of these systems are being developed and promulgated. The objective of each of these systems is the same, namely, improving safety by ensuring that vehicle lighting provides sufficient visibility for drivers without negative impacts such as glare. Recent research has shown the direct link between improved driver visibility and reduced nighttime crashes. To the extent that headlight evaluation systems can be compared using visual performance modeling approaches, it should be possible to relate improved visibility from high-performing headlight systems to the potential for reduced nighttime crashes. In the present paper we demonstrate how visual performance modeling in conjunction with vehicle headlight evaluations can lead to predictions of improved safety and ultimately, beneficial economic impacts to society
Preclinical laboratories at academic facilities and contract research organizations (CROs) have traditionally relied on five main imaging modalities: optical, acoustic, x-ray, MRI, and nuclear. Now, photoacoustic imaging, which combines optical and acoustic modalities, is enabling some of the most promising medical research, including providing images of biological structures for increased visibility during surgery and facilitating the analysis of plaque composition to better diagnose and treat coronary artery disease (CAD
Self-driving cars, like the human drivers that preceded them, need to see what’s around them to avoid obstacles and drive safely
Visual sensors are widely used in autonomous vehicles (AVs) for object detection due to the advantages of abundant information and low-cost. But the performance of visual sensors is highly affected by low light conditions when AVs driving at nighttime and in the tunnel. The low light conditions decrease the image quality and the performance of object detection, and may cause safety of the intended functionality (SOTIF) problems. Therefore, to analyze the performance limitations of visual sensors in low light conditions, a controlled light experiment on a proving ground is designed. The influences of low light conditions on the two-stage algorithm and the single-stage algorithm are compared and analyzed quantificationally by constructing an evaluation index set from three aspects of missing detection, classification, and positioning accuracy. Five main environmental influencing factors are tested and analyzed in typical nighttime urban driving scenarios: illuminance, the lateral
This document describes a practical system for a user to determine observer-to-aircraft distances. These observer-to-aircraft distances can be either closest point of approach (CPA) distances during field measurements or overhead distances during acoustic certification tests. The system uses a digital camera to record an image of the subject aircraft. A method of using commercial software to obtain the distance from such an image is presented. Potential issues which may affect accuracy are discussed
Conventional dental photography technology has had a limitation in using inconvenient tools such as mirrors and cheek retractors. Dentists require basic teeth images from various angles, such as right/left buccal and maxillary/mandibular occlusal, for dental health inspection. To acquire these images, patients feel discomfort because dentists must put a mirror into the mouth to capture the reflected teeth image through a handheld camera. Information such as tooth arrangement and the location of tooth decay can be obtained through this process. A compact intraoral dental camera can overcome the discomfort and scan the condition of teeth. However, due to the restricted depth of field and field of view, the conventional device has limitations in close-up imaging for observing tooth decay in detail and wide-angle imaging for capturing the entire arrangement of teeth
This SAE Recommended Practice describes the test procedures for conducting rear impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mount testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included
This SAE Recommended Practice describes the test procedures for conducting frontal impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mounting testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included
This SAE Recommended Practice describes the test procedures for conducting side impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mounting testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included
This document provides information regarding ice detector technology and design. The SAE document AS5498 provides detailed information regarding the requirements, specifications, qualification, and certification of icing detection systems. This document is not meant to replace AS5498, but to enhance it by considering unique aspects of sensing technology and, in particular, those that may not be certificated at the time of this revision. To that end, an effort has been made not to duplicate information contained in AS5498. Icing rate information is included where applicable. The primary application is associated with ice forming on the leading edges of airfoils and inlets while the aircraft is in flight. Information related to detection of ice over cold fuel tanks and icing at low-velocity operation is included. The material is primarily applicable to fixed-wing aircraft. Unique requirements for engine inlets and rotorcraft are also provided
This SAE standard applies to self-propelled driver operated sweepers and scrubbers as defined in SAE J2130-1
Dynamic simulation sled testing can represent various automotive collision conditions. Acceleration conditions during sled testing are readily reproducible and can be tuned to simulate collision events that occur during vehicle impacts with a fixed barrier or vehicle. Sled tests are conducted on automotive vehicle bodies or other structures to obtain valuable information. This information can be used to evaluate the dynamic performance of, but not limited to, vehicle restraint systems, vehicle seating systems, and body closure systems
Increasing financial commitment to accelerating and expanding electrified autonomous vehicle deployment promises vast societal and environmental benefits. The positive effects of these technological breakthroughs will be attained and maximized not only because of the improved energy conversion and optimized driving strategies of autonomous vehicles, but also through manufacturers’ intentional selection of energy efficient componentry. After reviewing the energy conversion advantages of electrified vehicles and the potential to optimize autonomous vehicle operation by optimizing their driving strategies in accordance with advanced driver assistance system performance, this paper highlights the broad implications of selecting energy efficient lidar sensors as the central components in autonomous vehicle perception stacks. Energy efficient components have significant impact on electrified autonomous vehicles’ overall range, energy consumption, and required service and maintenance
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