In Finland during the period 1972-1983, there were 3,564 severe traffic accidents involving one or more victims dying within 30 days of the accident. Forty-two of the victims had been wearing a seatbelt and had an abdominal trauma as the main cause of death or as first diagnosis of injury. Small intestine and colon injuries were more common in the severely injured victims than was the case with the fatally injured ones and in these accidents the injury mechanism was always deceleration or contusion, which was in most cases caused by the seatbelt. Liver injuries seem to be the major abdominal cause of fatality, and in the fatally injured group, half of the victims sustained the fatal abdominal injury through gross crushing impact. When the direction of the impact was analyzed, all the victims seated on the receiving side of the vehicle in lateral impact collisions sustained an abdominal injury with fatal outcome. It seems that the seatbelt is less effective in protecting wearers from severe or fatal abdominal injuries in lateral impact collisions.
The aim of this study was to assess the feasibility and quantitative potential benefits of a motorcycle autonomous emergency braking (MAEB) system in fatal rear-end crashes. A further aim was to identify possible criticalities of this safety system in the field of powered 2-wheelers (PTWs; e.g., any additional risk introduced by the system itself).
Seven relevant cases from the Swedish national in-depth fatal crash database were selected. All crashes involved car-following in which a non-anti-lock braking system (ABS)-equipped motorcycle was the bullet vehicle. Those crashes were reconstructed in a virtual environment with Prescan, simulating the road scenario, the vehicles involved, their precrash trajectories, ABS, and, alternatively, MAEB. The MAEB chosen as reference for the investigation was developed within the European Commission-funded Powered Two-Wheeler Integrated Safety (PISa) project and further detailed in later studies, with the addition of the ABS functionality. The boundary conditions of each simulation varied within a range compatible with the uncertainty of the in-depth data and also included a range of possible rider behaviors including the actual one. The benefits of the MAEB were evaluated by comparing the simulated impact speed in each configuration (no ABS/MAEB, ABS only, MAEB).
The MAEB proved to be beneficial in a large number of cases. When applicable, the benefits of the system were in line with the expected values. When not applicable, there was no clear evidence of an increased risk for the rider due to the system.
MAEB represents an innovative safety device in the field of PTWs, and the feasibility of such a system was investigated with promising results. Nevertheless, this technology is not mature yet for PTW application. Research in the field of passenger cars does not directly apply to PTWs because the activation logic of a braking system is more challenging on PTWs. The deployment of an autonomous deceleration would affect the vehicle dynamics, thus requesting an additional control action of the rider to keep the vehicle stable. In addition, the potential effectiveness of the MAEB should be investigated on a wider set of crash scenarios in order also to avoid false triggering of the autonomous braking.
Seatbelts were incorporated as standard equipment for automobiles constructed in North America in 1964. The first seatbelt law was made mandatory in Canada as of 1 January 1971. Between January 1976 and January 1980 38 patients involved in automobile accidents while wearing passive restraints were treated at l'Hôpital du Sacré-Coeur: 32 of these 38 patients had signs and symptoms of abdominal injury. These patients wearing passive restraints had an unusually high incidence of gastrointestinal injury in comparison to previously reported patients not wearing restraints. Twenty-seven of the 32 patients had injury to the bowel or the bowel mesentery. This different spectrum of injuries is most likely related to the altered physics of rapid deceleration caused by restraint with the lap belt and shoulder harness.
BACKGROUND: Decreased vagal activity after myocardial infarction results in reduced heart-rate variability and increased risk of death. To distinguish between vagal and sympathetic factors that affect heart-rate variability, we used a signal-processing algorithm to separately characterise deceleration and acceleration of heart rate. We postulated that diminished deceleration-related modulation of heart rate is an important prognostic marker. Our prospective hypotheses were that deceleration capacity is a better predictor of risk than left-ventricular ejection fraction (LVEF) and standard deviation of normal-to-normal intervals (SDNN). METHODS: We quantified heart rate deceleration capacity by assessing 24-h Holter recordings from a post-infarction cohort in Munich (n=1455). We blindly validated the prognostic power of deceleration capacity in post-infarction populations in London, UK (n=656), and Oulu, Finland (n=600). We tested our hypotheses by assessment of the area under the receiver-operator characteristics curve (AUC). FINDINGS: During a median follow-up of 24 months, 70 people died in the Munich cohort and 66 in the London cohort. The Oulu cohort was followed-up for 38 months and 77 people died. In the London cohort, mean AUC of deceleration capacity was 0.80 (SD 0.03) compared with 0.67 (0.04) for LVEF and 0.69 (0.04) for SDNN. In the Oulu cohort, mean AUC of deceleration capacity was 0.74 (0.03) compared with 0.60 (0.04) for LVEF and 0.64 (0.03) for SDNN (p
Comment In: Lancet. 2006 May 20;367(9523):1639-4116714171
Adaptive Cruise Control (ACC) has been shown to reduce the exposure to critical situations by maintaining a safe speed and headway. It has also been shown that drivers adapt their visual behavior in response to the driving task demand with ACC, anticipating an impending lead vehicle conflict by directing their eyes to the forward path before a situation becomes critical. The purpose of this paper is to identify the causes related to this anticipatory mechanism, by investigating drivers' visual behavior while driving with ACC when a potential critical situation is encountered, identified as a forward collision warning (FCW) onset (including false positive warnings). This paper discusses how sensory cues capture attention to the forward path in anticipation of the FCW onset. The analysis used the naturalistic database EuroFOT to examine visual behavior with respect to two manually-coded metrics, glance location and glance eccentricity, and then related the findings to vehicle data (such as speed, acceleration, and radar information). Three sensory cues (longitudinal deceleration, looming, and brake lights) were found to be relevant for capturing driver attention and increase glances to the forward path in anticipation of the threat; the deceleration cue seems to be dominant. The results also show that the FCW acts as an effective attention-orienting mechanism when no threat anticipation is present. These findings, relevant to the study of automation, provide additional information about drivers' response to potential lead-vehicle conflicts when longitudinal control is automated. Moreover, these results suggest that sensory cues are important for alerting drivers to an impending critical situation, allowing for a prompt reaction.
The aim of the present study was to evaluate the crash mitigation performance of low-speed automated emergency braking collision avoidance technologies by examining crash rates, car damage, and personal injuries.
Insurance claims data were used to identify rear-end frontal collisions, the specific situations where the low-speed automated emergency braking system intervenes. We compared cars of the same model (Volvo V70) with and without the low-speed automated emergency braking system (AEB and no AEB, respectively). Distributions of spare parts required for car repair were analyzed to identify car damage, and crash severity was estimated by comparing the results with laboratory crash tests. Repair costs and occupant injuries were investigated for both the striking and the struck vehicle.
Rear-end frontal collisions were reduced by 27% for cars with low-speed AEB compared to cars without the system. Those of low severity were reduced by 37%, though more severe crashes were not reduced. Accordingly, the number of injured occupants in vehicles struck by low-speed AEB cars was reduced in low-severity crashes. In offset crash configurations, the system was found to be less effective.
This study adds important information about the safety performance of collision avoidance technologies, beyond the number of crashes avoided. By combining insurance claims data and information from spare parts used, the study demonstrates a mitigating effect of low-speed AEB in real-world traffic.
In 2006, Motorcycle Autonomous Emergency Braking (MAEB) was developed by a European Consortium (Powered Two Wheeler Integrated Safety, PISa) as a crash severity countermeasure for riders. This system can detect an obstacle through sensors in the front of the motorcycle and brakes automatically to achieve a 0.3 g deceleration if the collision is inevitable and the rider does not react. However, if the rider does brake, full braking force is applied automatically. Previous research into the potential benefits of MAEB has shown encouraging results. However, this was based on MAEB triggering algorithms designed for motorcycle crashes involving impacts with fixed objects and rear-end crashes. To estimate the full potential benefit of MAEB, there is a need to understand the full spectrum of motorcycle crashes and further develop triggering algorithms that apply to a wider spectrum of crash scenarios.
In-depth crash data from 3 different countries were used: 80 hospital admittance cases collected during 2012-2013 within a 3-h driving range of Sydney, Australia, 40 crashes with Injury Severity Score (ISS)>15 collected in the metropolitan area of Florence, Italy, during 2009-2012, and 92 fatal crashes that occurred in Sweden during 2008-2009. In the first step, the potential applicability of MAEB among the crashes was assessed using a decision tree method. To achieve this, a new triggering algorithm for MAEB was developed to address crossing scenarios as well as crashes involving stationary objects. In the second step, the potential benefit of MAEB across the applicable crashes was examined by using numerical computer simulations. Each crash was reconstructed twice-once with and once without MAEB deployed.
The principal finding is that using the new triggering algorithm, MAEB is seen to apply to a broad range of multivehicle motorcycle crashes. Crash mitigation was achieved through reductions in impact speed of up to approximately 10 percent, depending on the crash scenario and the initial vehicle pre-impact speeds.
This research is the first attempt to evaluate MAEB with simulations on a broad range of crash scenarios using in-depth data. The results give further insights into the feasibility of MAEB in different speed ranges. It is clear then that MAEB is a promising technology that warrants further attention by researchers, manufacturers, and regulators.
The efficacy of seat belts in reducing deaths from motor vehicle crashes is well documented. A unique association of injuries has emerged in adults and children with the use of seat belts. The "seat-belt syndrome" refers to the spectrum of injuries associated with lap-belt restraints, particularly flexion-distraction injuries to the spine (Chance fractures).
We describe the injuries sustained by 8 children, including 2 sets of twins, in 3 different motor vehicle crashes.
All children were rear seat passengers wearing lap or 3-point restraints. All had abdominal lap-belt ecchymosis and multiple abdominal injuries due to the common mechanism of seat-belt compression with hyperflexion and distraction during deceleration. Five of the children had lumbar spine fractures and 4 remained permanently paraplegic.
These incidents illustrate the need for acute awareness of the complete spectrum of intra-abdominal and spinal injuries in restrained pediatric passengers in motor vehicle crashes and for rear seat restraints that include shoulder belts with the ability to adjust them to fit smaller passengers, including older children.
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Current and previous placement of wildlife warning signs by the Finnish Road Administration is based on suggestions from hunting associations and individuals. The problem within this practice is that the placement of warning signs is not a transparent process. Within this paper, we evaluate the current placement of wildlife warning signs for the Uusimaa region in southern Finland and develop a method to optimise warning sign placement using kernel density estimations, which are based on existing wildlife-vehicle accident records. The contour lines of these densities can indicate the road sections to be marked with warning signs. To apply a well-documented computational method, based on these moose and white-tailed deer accident locations, assists the Finnish Road Administration in their task to place, replace and assess wildlife-warning signs for specific road sections.