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The objectives of this study were to provide insights on how injury risk is influenced by occupant demographics such as sex, age, and size; and to quantify differences within the context of commonly-occurring real-world crashes. The analyses were confined to either single-event collisions or collisions that were judged to be well-defined based on the absence of any significant secondary impacts. These analyses, including both logistic regression and descriptive statistics, were conducted using the Crash Investigation Sampling System for calendar years 2017 to 2021. In the case of occupant sex, the findings agree with those of many recent investigations that have attempted to quantify the circumstances in which females show elevated rates of injury relative to their male counterparts given the same level bodily insult. This study, like others, provides evidence of certain female-specific injuries. The most problematic of these are AIS 2+ and AIS 3+ upper-extremity and lower-extremity injuries. These are among the most frequently observed injuries for females, and their incidence is consistently greater than for males. Overall, the odds of females sustaining MAIS 3+ (or fatality) are 4.5% higher than the odds for males, while the odds of females sustaining MAIS 2+ (or fatality) are 33.9% higher than those for males. The analyses highlight the need to carefully control for both the vehicle occupied, and the other involved vehicle, when calculating risk ratios by occupant sex. Female driver preferences in terms of vehicle class/size differ significantly from those of males, with females favoring smaller, lighter vehicles.

Abstract: Historically, data related to motor vehicle safety generated by Canadian government regulators has been shared extensively with the equivalent authorities in the United States. This has provided opportunities for Canadian research findings to be integrated into regulations affecting the entire North American vehicle fleet as well as addressing this country's specific interests. While Transport Canada continues to have the possibility of improving the technical basis of the US-led programmes through its research, this can only be accomplished through the adoption of an open and transparent policy towards the dissemination of its crash test and collision investigation data. Unfortunately, although the department professes to provide "responsible" disclosure, in actual practice, there continues to be a degradation of transparency and public scrutiny of the data being generated in Canada. Conversely, the openness practised in the US benefits all stakeholders. Data from motor-vehicle crash tests conducted for the purposes of both regulatory compliance and safety research, and those from real-world collision investigations, need to be widely shared. By implementing an approach similar to the US, which provides full disclosure of such data, Transport Canada could provide a platform allowing external stakeholders to build on the findings of its work, increasing the potential for further enhancement of the safety of motor vehicle occupants.

Résumé : De tous temps, les organismes de réglementation du gouvernement canadien ont largement partagé leurs données en matière de sécurité des véhicules automobiles avec leurs homonymes des États-Unis. C'est ainsi que les résultats des recherches canadienne ont pu être intégrés à la réglementation touchant l'ensemble du parc automobile nord-américain et abordant les questions d'intérêt propres à ce pays. Certes, Transport Canada profite toujours de la possibilité d'améliorer par ses recherches les fondements techniques des programmes menés par les États-Unis, mais cette possibilité repose sur une politique d'ouverture et de transparence en matière de diffusion de ses résultats de tests de collision et d'enquêtes sur les collisions. Malheureusement, bien que le Ministère affirme exercer une communication " responsable ", en pratique, la transparence et l'examen public des données générées au Canada ne cessent de se détériorer. À l'inverse, l'ouverture pratiquée par les États-Unis profitent à tous les partenaires. Il est essentiel de partager largement, d'une part, les résultats des essais de collision de la route réalisés tant à des fins de conformité à la réglementation que de recherche sur la sécurité, et, d'autre part, ceux des enquêtes sur les collisions réelles. En instaurant une approche similaire à celle des États-Unis, avec communication complète des résultats, Transport Canada pourrait fournir une plateforme où les partenaires externes pourraient tirer parti des conclusions de ses travaux, ce qui permettrait d'optimiser la sécurité des occupants des véhicules.

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There has been much discussion in recent years on the topic of autonomous vehicles; however, while these are under active development and even, in some cases, are on the road as limited test fleets, their full potential has yet to be exploited. Nevertheless, a number of the underlying technologies and sub-systems are making their way into the current vehicle fleet. Marketed as Advanced Driver Assistance Systems (ADAS), many current production vehicles are equipped with a variety of such high-tech systems.

Il y a eu beaucoup de discussions, ces dernières années, autour des véhicules autonomes. Toutefois, bien qu'ils sont actuellement en développement et, dans certains cas, soient soumis à des tests routiers, le potentiel des véhicules autonomes reste à exploiter. Il faut également reconnaître qu'un certain nombre de technologies a déjà fait son apparition dans le parc de véhicules. Commercialisés sous l'appellation ADAS (Advanced Driver Assistance Systems), les systèmes avancés d'aide à la conduite font partie intégrante de plusieurs véhicules de série.

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The potential introduction of fully-autonomous vehicles into the vehicle fleet means that, in future, many vehicle manoeuvres will be governed by automatic systems rather than by vehicle drivers. In fact, this is often the case today due to the increasing implementation of Advanced Driver Assistance Systems (ADAS) in production vehicles. These trends make it imperative that the sensing and control systems associated with on-board automated systems are carefully monitored, and their actions fully recorded, so that their performance can be evaluated following any unexpected event such as a collision. In this article we look at some of the latest features of Event Data Recorders (EDR) that facilitate this process.

L'introduction de véhicules entièrement autonomes dans le parc de véhicules signifiera qu'à l'avenir, les manoeuvres de véhicules seront régies par des systèmes de prise de décision automatisés, plutôt que par des conducteurs. En fait, c'est déjà le cas bien souvent aujourd'hui, en raison de la présence de plus en plus importante des systèmes avancés d'aide à la conduite. Compte tenu de cette tendance, il est impératif que les systèmes de détection et de contrôle associés aux systèmes automatisés soient surveillés de près et que leurs actions soient enregistrées, afin de pouvoir évaluer leur performance à la suite d'événements imprévus, telles que les collisions. Dans cet article, nous examinons certaines des dernières fonctionnalités propres aux enregistreurs d'événement qui facilitent ce processus.

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Vulnerable road users, notably pedestrians and cyclists, are at particular risk of death and serious injury when subject to adverse interactions with heavy commercial vehicles. Such situations are primarily a problem in urban environments, and at intersections, where heavy vehicles undertake turning manoeuvres. A study of real-world collisions involving heavy vehicles and vulnerable road users was conducted to identify the major causal factors related to the occurrence of fatalities in such crashes and to determine a range of appropriate countermeasures. The results demonstrate that the problem is largely due to an inability of the drivers of heavy vehicles to note the presence of adjacent vulnerable road users, and pedestrians and cyclists not being fully aware of the intentions and trajectories of the heavy trucks. The study strongly suggests that, for heavy trucks and buses, two very effective measures would be improvements to on-board driver-assistance safety systems, and greater public awareness of the dangers posed by heavy vehicles operating in urban environments.

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Passive systems in vehicles that are designed to detect driver alcohol impairment have been under development for a number of years. One such research programme in the United States brings together government and industry to explore the feasibility, benefits, and the challenges associated with the use of such in-vehicle technologies.

Les systèmes passifs embarqués dans les véhicules pour détecter l'alcool au volant sont en cours de développement depuis de nombreuses années. Entres autres, un programme de recherche aux États-Unis rassemble le gouvernement et l'industrie pour explorer la faisabilité, les avantages et les défis associés à l'utilisation de telles technologies embarquées.

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For many years racing car drivers have appreciated the benefits of slipstreaming, or drafting, behind an opponent's vehicle in order to reduce aerodynamic drag on their own race car and provide a potential speed advantage in a subsequent overtaking manoeuvre. In the field of commercial transportation, recent advances in electronic sensors and vehicle control systems, seem poised to provide further aerodynamic efficiencies for heavy trucks. However, the goal here is not to have trucks travel faster, rather it is to reduce their fuel consumption.

Des recherches menées au Canada et aux États-Unis ont pour but d'identifier des économies potentielles de carburant découlant de l'utilisation de " pelotons " de semi-remorques. Le véhicule principal est conduit normalement, alors que chaque véhicule suivant utilise un régulateur de vitesse adaptatif coopératif pour maintenir un intervalle de temps spécifique entre lui-même et le camion devant lui. En limitant les distances inter-véhicules on réduit la traînée aérodynamique sur les véhicules qui se trouvent dans le peloton, ce qui se traduit par des économies de carburant pour l'ensemble du peloton.

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Most people will be familiar with the fact that technology companies such as Google and Uber are in the process of developing autonomous (self-driving) cars, and that many mainstream automobile manufacturers have plans to bring such vehicles to market at some point in the future. But what about heavy trucks? Do self-driving technologies have a role to play in "big rigs"?

La plupart des gens sont au courant que les entreprises technologiques telles que Google et Uber sont en train de développer des véhicules autonomes (conduite automatisée, "self-driving") et que de nombreux constructeurs automobiles ont l'intention de les commercialiser dans un avenir proche. Mais que passera-t-il avec les véhicules lourds ? Est-ce que les technologies autonomes joueront un rôle chez les grands camions ?

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Event Data Recorders (EDR's) have been installed in many motor vehicles since the 1990's. With the advent of sophisticated occupant restraint systems, including belt pretensioners and smart airbags, EDR's have recorded an increasing number of crash-related parameters. Similarly, advanced collision avoidance systems have become prevalent in the vehicle fleet and EDR's are now used to capture a wide range of pre-crash data elements relating to this technology and the resulting status of the vehicle and its control systems. Such data provide a wealth of information related to driver actions, and on the functionality and effectiveness of vehicle safety systems. The current paper will provide an overview of the scope of data elements captured by modern EDR's and will demonstrate the utility of these data through case studies of real-world events.

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The Insurance Institute for Highway Safety has recently introduced a small overlap frontal crash test in its frontal rating scheme. Another small overlap frontal crash test is under development by the National Highway Traffic Safety Administration (NHTSA). Whereas the IIHS test is conducted against a fixed rigid barrier, the NHTSA test is conducted with a moving deformable barrier that overlaps 35% of the vehicle being tested and the angle between the longitudinal axis of the barrier and the longitudinal axis of the test vehicle is 15 degrees. The field relevance of the IIHS test and the NHTSA test has been the subject of previous papers by Prasad et al. The current study is aimed at examining the combined relevance of the two tests as representing frontal corner impacts involving small overlap. The field relevance is indicated by the frequency of occurrence of real world crashes that are simulated by the test conditions, the proportion of serious-to-fatal real world injuries explained by the test conditions, and rates of serious injury to the head, chest and other body regions in the real world crashes resembling the test condition. The database examined for real world crashes is NASS-CDS. The frontal corner impacts as represented by the 25% Small overlap frontal and the NHTSA tests together address slightly less than 9% of all frontal crashes and 6% to 12% of all MAIS3+F injuries to the drivers in these crashes. The IIHS test has a somewhat higher contribution in both the incidence and severity. The two crash modes together address 4.6% to 8.2% of all MAIS3+F head injuries. Similarly, the proportion of all frontal MAIS3+F chest injuries addressed by the two crash modes or corner tests is estimated to be 6% to 10.6%. The available data for the passenger involved in driver-side frontal corner crashes indicate that elderly female occupants predominantly experience serious head and chest injuries. All, except one, injured passengers were females. The average age of injured females who had chest injuries was slightly over 65 years. Injury rates of the head and the chest are substantially lowered in far-side than in near-side frontal impacts. Crash test ATD rotational responses of the head in the tests substantially over predict the real world risk of serious-to-fatal brain injuries.

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In recent years, due to initiatives such as Road Safety Vision 2010, and the National Occupant Restraint Program, Canada has seen reductions in casualties resulting from motor vehicle collisions. Indeed, the most recent collision statistics, published in 2012, show the lowest death toll on the nation's roads in almost sixty years. Furthermore, the most recent seat belt surveys, conducted in 2009-10, indicate that Canadians are buckling up in motor vehicles more than ever, with an overall usage rate in excess of 95%. Despite these very encouraging signs, the percentage of motor vehicle occupants who are fatally injured while not using seat belts remains unacceptably high at more than 35%. This problem is particularly well exemplified by fatalities resulting from single-vehicle rollover crashes. Such collisions frequently occur as a result of loss of directional control on the part of the driver, and involve vehicle yaw and a lateral rollover, a crash mode that is often benign. Belted occupants are generally retained inside the vehicle and come to little harm. However, such may well not be the case for the unbelted who are in considerable danger of being ejected from the vehicle, with the consequent potential for serious or fatal injury. The present study looks at this latter issue, both from the perspective of the national collision picture, and from a series of in-depth investigations of fatal crashes.

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A small overlap frontal crash test has been recently introduced by the Insurance Institute for Highway Safety in its frontal rating scheme. Another small overlap frontal crash test is under development by the National Highway Traffic Safety Administration (NHTSA). Whereas the IIHS test is conducted against a fixed rigid barrier, the NHTSA test is conducted with a moving deformable barrier that overlaps 35% of the vehicle being tested and the angle between the longitudinal axis of the barrier and the longitudinal axis of the test vehicle is 15 degrees. The field relevance of the IIHS test has been the subject of a paper by Prasad et al. (2014). The current study is aimed at examining the field relevance of the NHTSA test. The field relevance is indicated by the frequency of occurrence of real world crashes that are simulated by the test conditions, the proportion of serious-to-fatal real world injuries explained by the test condition, and rates of serious injury to the head, chest and other body regions in the real world crashes resembling the test condition. The database examined for real world crashes is NASS. Results of the study indicate that 1.4% of all frontal 11-to-1 o'clock crashes are simulated by the test conditions that account for 2.4% to 4.5% of all frontal serious-to-fatal (MAIS3+F) injuries. Injury rates of the head and the chest are substantially lower in far-side than in near-side frontal impacts. Crash test ATD rotational responses of the head in the tests over-predict the real world risk of serious-to-fatal brain injuries.

Full-text paper available from SAE

Video camera technology is being used to provide blind spot detection for drivers when reversing or turning right. NHTSA has issued a final rule requiring rear visibility technology in all new light-duty vehicles by 2018.

Video cameras have been miniaturized, and their sensor systems refined in terms of their field of view and light-gathering ability. The cost of video cameras has been reduced considerably, and they are now being widely adapted for in-vehicle applications.

Rear-view cameras and in-dash display screens are being installed in many new vehicle models. These provide a broad view to the rear of the vehicle, with software often being used to overlay a grid on the image, indicating distances to objects to the rear of the vehicle.

Similar camera systems may be embedded in a vehicle's side mirrors. These systems provide additional coverage of blind spots and may be activated automatically, by use of the turn signals, or under the manual control of the driver.

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Current event data recorders provide data on an expanded range of occupant protection systems, in addition to a wide variety of data elements relating to pre-crash driver actions and the performance of collision avoidance systems.

Les enregistreurs actuels de données d'événements fournissent des données sur une grande gamme de systèmes de protection des occupants, en plus d'une grande variété d'éléments de données relatives aux actions des conducteurs avant la collision et à la performance des systèmes anti-collision.

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In North America, frontal crash tests in both the regulatory environment and consumer-based safety rating schemes have historically been based on full-width and moderate-overlap (40%) vehicle to barrier impacts. The combination of improved seat-belt technologies, notably belt tensioning and load limiting systems, together with advanced airbags, has proven very effective in providing occupant protection in these crash modes. Recently, however, concern has been raised over the contribution of narrower frontal impacts, involving primarily the vehicle corners, to the incidence of fatality and serious injury as a result of the potential for increased occupant compartment intrusion and performance limitations of current restraint systems.

Drawing on data documented in the National Automotive Sampling System (NASS)/ Crashworthiness Data System (CDS) for calendar years 1999 to 2012, the present study examines the characteristics of existing and proposed corner crash test configurations, and the nature of real-world collisions that approximate the test environments. In this analysis, particular emphasis is placed on crash pulse information extracted from vehicle-based event data recorders (EDR's).

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This paper presents the analysis of a series of frontal crash tests conducted by the Insurance Institute of Highway Safety that are commonly referred to as Small Overlap Impacts (SOI). The occurrence and severity of such frontal impacts in the real world were estimated using two different methods. Both methods used the National Automotive Sampling Scheme (NASS), which is a stratified sample of crashes in the US.

The first method utilized an algorithm commonly known as Frontal Impact Taxonomy (FIT). The second method was based on comparison of deformation patterns of vehicles involved in frontal crashes in the NASS data files with those produced in tests conducted by the IIHS.

FIT analysis of the data indicate that approximately 7.5% of all 11-1 o'clock frontal crashes in NASS are represented by the IIHS SOI test condition and they account for 6.1% of all serious-to-fatal injuries to front seat occupants restrained by seat belts and airbags. Based on the analysis of test and crash front end damage data, it is estimated that the IIHS SOI test mode represents 3% to 8% of all fatal crashes and 4.6 to 9% of all MAIS3+F injury producing frontal crashes.

Full-text paper available from SAE

Public complaints of unintended acceleration in motor vehicles are regularly received by Transport Canada's Defect Investigations and Recalls group. Some years ago, a major study of such cases was conducted using conventional investigative techniques, including physical inspections of subject vehicles and in-depth interviews with their operators. The results of this study demonstrated that the phenomenon was essentially due to operator error and not related to malfunction of any vehicle control system. In particular, the incidents resulted from so-called “pedal error” where drivers were pressing down hard on the accelerator pedal while believing themselves to be fully applying the vehicle's brakes. The advent of vehicles equipped with event data recorders (EDR's) capable of storing a range of pre-collision information, including the status of the brake-light switching circuit, and the disposition of both the accelerator pedal and vehicle throttle, has provided investigators with an objective dataset with which to evaluate unintended acceleration complaints. The present work uses recent public complaints of such incidents that have been received by Transport Canada, where the case vehicles were equipped with EDR's, and pre-crash data stored on these devices were downloaded following the alleged incidents. The analysis of these data clearly demonstrates the potential for EDR's to assist in determining the precise operator actions leading up to unintended acceleration incidents.

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Recently, media attention has been focussed on a recommendation from the Office of the Chief Coroner of Ontario that side guards should be installed on heavy trucks in order to protect pedestrians; however, other research suggests that this safety issue may be somewhat more complex.

"Transport Canada should make side-guards mandatory on heavy trucks in Canada. In addition, consideration should be given to requiring additional equipment (such as blind spot mirrors and blind spot warning signs) to make pedestrians more visible to trucks and decrease the chance of a collision, especially during right-hand turns."

However, while the authors of the NRC report do indeed indicate a reduction in pedestrian fatalities following the mandating of truck side guards, they go on to state that: "…it is not clear if this reduction is entirely related to side guards or if side guards are but one of the contributing factors." Furthermore, their report includes the statement that: "It is not clear if side guards will reduce deaths and serious injury or if the guards will simply alter the mode of death and serious injury." There is, therefore, some question over the efficacy of side guards as an appropriate countermeasure.

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Not surprisingly, pedestrians, cyclists, and motorcyclists are especially vulnerable in collisions with much more massive, and much faster moving, motor vehicles. Even at relatively low contact speeds the outcome for such individuals can be serious injuries or even fatalities. In jurisdictions such as Europe, where the involvement of vulnerable road users in serious collisions is greater than in North America, specific consideration has been given to the protection of these individuals through vehicle-based countermeasures.

In the late 90's the European New Car Assessment Programme (EuroNCAP) began incorporating safety ratings for vehicles based on pedestrian-friendly designs. Structural changes to motor vehicles, necessitated by the desire of manufacturers to obtain good pedestrian protection scores in EuroNCAP tests, have included deformable bumpers, softer edges on the hood, and providing clearance between the top surface of the hood and the underlying structures of the engine assembly.

A more recent innovation, developed by Volvo Car Corporation, has been the deployment of an external air bag that both lifts the hood in order to create deflection space, and provides a shield over the bottom of the windshield frame and the lower portions of the front roof pillars to protect against head contact with these stiff structures.

Volvo, a company renowned for its vehicle safety innovations, has also developed a series of countermeasures designed to locate vulnerable road users ahead of the vehicle's path of travel, predict their likely movements, and identify hazardous situations where a collision might occur. In such cases, the driver is alerted, while the vehicle itself is capable of fully applying the brakes in order to prevent a crash or at least reduce the impact speed.

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Following up on the concepts used to determine that "work is mad", we explore the possibilities for vehicles to "stop on a dime" and discover that, sometimes, they actually need a loonie!

The paper provides an example of calculating a vehicle's total stopping distance as the distance travelled during the period of the driver's perception-reaction to a hazard and the distance travelled under subsequent hard braking. Similar calculations for different initial speeds show the potential dangers in increased speed.

We look at a vehicle that can just brake to a halt and avoid a crash and find that a vehicle travelling just 5 km/h faster will undergo a collision with an impact speed of 30 km/h!

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In recent years, major advances in field data collection and analysis have been achieved through the integration of real-world vehicle crash data captured by on-board, electronic, event data recorders (EDR's). For some time, data has been publicly available from EDR's in General Motors, Ford, and Chrysler vehicles. Recently, Toyota has provided a proprietary tool through which researchers can access EDR's installed in their vehicles. The current study looks at the crash data that are available and explores the accuracy of this information. The study uses a series of staged collisions with EDR-equipped vehicles and compares data downloaded from these devices to equivalent information captured by laboratory instrumentation. Full-frontal crash tests, conducted by Transport Canada, at 48 km/h into a rigid barrier are used. The results show generally good agreement between the two datasets, with some limitations in the EDR-reported data being noted. These comparisons of data obtained from on-board vehicle EDR's, with equivalent information collected using sophisticated laboratory instrumentation, provide a valuable measure of confidence in the use of similar data collected from real-world events.

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Increasingly, vehicle manufacturers are developing tools which allow access to data stored on on-board event data recorders (EDR's). The information stored by such devices have the potential for providing levels of insight into crashes well beyond that achievable with conventional collision reconstruction techniques. The current work identifies the nature of the stored data that can be retrieved from the on-board event data recorders in Toyota vehicles, and evaluates the accuracy of the crash pulse data based on information obtained from frontal crash tests. An overview of the pre-crash and crash-pulse data provided by Toyota EDR's is presented. The accuracy of the crash-pulse data is explored from a series of staged collisions with EDR-equipped vehicles. Data downloaded from the EDR's are compared to equivalent information captured by laboratory instrumentation. Full-frontal crash tests, over a range of test speeds, and conducted on a number of different model vehicles, are used in the study.

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In recent years, major advances in field data collection and analysis have been achieved through the integration of real-world vehicle crash data captured by on-board, electronic, event data recorders (EDR's). To date, publicly-available data have been limited to just two manufacturers, namely General Motors and Ford. Recently, Chrysler has provided a tool by which researchers can access EDR's installed in their vehicles. The current study looks at the new crash data that are now available from Chrysler vehicles and explores the accuracy of this information. The study uses data from a series of staged collisions with EDR-equipped vehicles and compares data downloaded from these devices to equivalent information captured by laboratory instrumentation. Full-frontal crash tests, over a range of test speeds, and conducted on a number of different model vehicles, are used in the study.

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Many vehicles equipped with air bags also have on-board crash recording systems that, in the event of a frontal collision, capture information relating to the crash, and the deployment of safety systems such as seat belt pretensioners and air bags. Typically, event data recorders (EDR) store details of the collision itself, such as the crash pulse, seat belt pretensioner and air bag firing times, and also certain pre-crash data elements such as vehicle speed, throttle and brake application, and seat belt use status. For a number of years, collision investigators have been able to download the data stored in many General Motors and Ford vehicles through the use of a crash data retrieval tool. Such records provide an opportunity to gain a better understanding of the parameters related to real-world collisions as they afford access to objective crash data with known levels of uncertainty. The current work uses EDR information from in-depth investigations of real-world collisions in Canada. Frontal impacts are categorized by crash type and severity. The resulting subsets of crash pulses and restraint system activation times are compared to data captured as part of staged crash tests that have been undertaken for both regulatory purposes and research. This provides considerable insight into the utility of regulatory crash tests and the nature of the compliance strategies adopted by vehicle manufacturers.

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