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Using dashcam video footage to extract reliable vehicle speed data can be challenging when the only available image stream comes from a camera whose optical parameters are unknown. One means of overcoming such difficulties uses visible landmarks and features within the video frame whose dimensions can be independently measured. While good results have been obtained by others using a Total Station or LiDAR to physically measure locations for such purposes, this approach could prove difficult if a site of interest is inaccessible (e.g. on a busy highway that cannot be shut down) or if relevent features of the target location have changed (e.g. due to construction or even restriping of lanes lines). As an alternative to direct scene measurement, it is proposed that measurement of features visible in overhead satellite images be used to dimension relevant features visible in the video.

This paper outlines the characteristics of rollover accidents based on a representative sample of British cars and light vans. The data come from on-the-spot and follow up investigations of accidents conducted by Birmingham University and the Ford Motor Company in which damaged vehicles were examined and information from them correlated with injury data obtained from hospitals. Rollovers are either initiated by impact with another vehicle or are simple rolls, the incidence of other types of roll being low. Door opening rates are shown to be high, and the character of roof collapse, in terms of position and amount, is described. The sources of injury to occupants is discussed. Injury to the head or face occurred in 96% of injured occupants. Seat belts, when worn, prevent ejection but cannot offer complete immunity from injury in this type of accident. Some improvements in crash performance are outlined and a tentative testing procedure is mentioned.

In recent investigations of airbag deployments, drivers h v c reported abrasions to the face, neck, and forearms due to deploying airbags, A study of the airbag design and deployments parameters affecting the incidence and severity of abrasions caused by driver-side airbags has led to the development of a laboratory test procedure to evaluate the potential of an airbag design m cause skin injury This report describes the procedure, which is based an static deployments of airbags into a cylindrical lest fixture. The target area is covered with a material that responds to abrasion-producing events in a manner related to human skin tolerance. Test results show excellent correlation with abrasion injuries produced by airbag deployments into the skin of human volunteers.

When developing an airbag system with mechanical sensors, one of the important stages is to get satisfactory correlation between the sensor characteristics and the specific vehicle. This development stage requires control of both vehicle crashworthiness (including selection of sensor mount location) and airbag sensor characteristics. This stage is ordinarily performed through many iterations of a computer simulation which involves the dynamic structure of the sensor mechanism. A new graphic method is proposed in this paper to help in this simulation stage. This method can estimate the proper threshold level of the crash sensor. The airbag sensor mount location in the vehicle can be selected and the airbag sensor can be developed. The validity of the method has been verified by computer simulation as well as actual test results.

Engine operation produces particles that contaminate the lubricating oil and can damage the engine's internal components. This paper presents a model for a three-coil inductive metal particle sensor and verifies the rationality and accuracy of the model by simulating the motion of a single spherical iron particle passing through the sensor. On this basis, the simulation of coupling double particles with different sizes, distances, and shapes is carried out. The study explores the influence of particle motion on the sensor-induced signal under various conditions. The research shows that when two particles pass through the sensor, the induced voltage signal will produce superposition when the distance between the two particles is small. The peak value of the induced voltage is 1-2 times the peak value of the induced voltage of a single particle. As the distance increases, the peak value of the induced voltage initially decreases, then slowly increases, and finally stabilizes.

Scientific methodology and engineering techniques were applied to a series of three automobile rear-end collision experiments to provide data relating to seat, seat backrest, and head-restraint design. Five seat back heights and four seat back strength values were studied in connection with their practicality and relative protective features, when subjected to a 55 mph rear-end collision exposure. These research data provide a basic reference system of high-speed collision performance for seat designs with respect to occupant size and proximity to injury producing structures. Additionally, methodology, instrumentation, and related equipment required for post-crash fire studies were included in experiment 106, providing what is believed to be the first published data on the precise time-related events associated with collision-induced passenger car fires. Design revisions suggested by these findings are discussed.

The recent demand for power generation capability has raised the operating temperature of the power plants in the range of 600°C. High operating temperature leads to material degradation or reduced lifespan of boilers, which necessitates the analysis of the high-temperature behavior of welded joints of power plant boilers for a long lifespan and improved efficiency. Gr91 martensitic and SS304 austenitic stainless steel are identified as the primary piping material for these boilers. The boiler piping involves similar weld joints (Gr91/Gr91 and SS304/SS304) and dissimilar weld joints (SS304/Gr91) known as transition joints. These joints are exposed to high temperatures for a long duration during their service and it is therefore necessary to evaluate the high-temperature behavior of these weld joints. The hot tensile test is a short-term high-temperature test that serves as a valuable tool for analyzing the high-temperature behavior of the welds.

In this paper, a control strategy for state of charge (SOC) allocation using navigation data for Hybrid Electric Vehicle (HEV) propulsion systems is proposed. This algorithm dynamically defines and adjusts a SOC target as a function of distance travelled on-line, thereby enabling proactive management of the energy store in the battery. The proposed approach incorporates variances in road resistance and adheres to geolocation constraints, including ultra-low emission zones (uLEZ). The anticipated advantages are particularly pronounced during scenarios involving extensive medium-to-long journeys characterized by abrupt topological changes or the necessity for exclusive electric vehicle (EV) mode operation. This novel solution stands to significantly enhance both drivability and fuel economy outcomes.

This paper focuses on an inherent problems of active damping control prevalent in contemporary hybrid torque controls. Oftentimes, a supervisory torque controller utilizes simplified system models with minimal system states representation within the optimization problem, often not accounting for nonlinearities and stiffness. This is motivated by enabling the generation of the optimum torque commands with minimum computational burden. When inherent lash and stiffness of the driveline are not considered, the resulting command can lead to vibrations and oscillations in the powertrain, reducing performance and comfort. The paper proposes a Linear Quadratic Integral (LQI)-based compensator to be integrated downstream the torque supervisory algorithm, which role is to shape transient electric machine torques, compensating for the stiffness and backlash present in the vehicle while delivering the driver-requested wheel torque.

The goal of this study was to use naturalistic driving data to characterize the motion of vehicles making right turns at signalized intersections. Right-turn maneuvers from 13 intersections were extracted from the Second Strategic Highway Research Program (SHRP2) database and categorized based on whether or not the vehicle came to a stop prior to making its turn. Out of the vehicles that did stop, those that were the first and second in line at the intersection were isolated. This resulted in 186 stopped first-in-line turns, 91 stopped second-in-line turns, and 353 no stop turns. Independent variables regarding the maneuver, including driver’s sex and age, vehicle type, speed, and longitudinal and lateral acceleration were extracted. The on-board video was reviewed to categorize the road as dry/wet and if it was day/night. Aerial photographs of the intersections were obtained, and the inner radius of the curve was measured using the curb as a reference.

A considerable amount of research has been conducted to evaluate the effects of road surface discontinuities and disturbances on vehicle dynamics and accident causation. This paper addresses the real world effects of these conditions by reviewing the analyses of actual physical evidence of accidents involving alleged road defects. Analysis and testing techniques are described and alternative causative elements are presented.