| 1. |
- Mishra, Ekant, et al.
(författare)
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Effects of Automated Emergency Braking and Seatbelt Pre-Pretensioning on Occupant Injury Risks in High-Severity Frontal Crashes
- 2022
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Ingår i: Frontiers in Future Transportation. - : Frontiers Media SA. - 2673-5210. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- In high-severity crashes, occupant protection is challenging. Automated Emergency Braking (AEB) and seatbelt pre-pretensioning (PPT) are means to improve occupant protection; the purpose of this study was to quantify their effects on occupant injury risks in high-severity full-frontal crashes by Finite Element (FE) simulations. The SAFER Active average male Human Body Model was used as an occupant substitute. The crash pulses used were from separate full-frontal crash simulations using a Honda Accord FE model. The vehicle interior model comprised a seat, an instrument panel, a three-point pretensioned seatbelt system with a load-limiter of 3.1 kN force level, and a frontal passenger airbag. The effects of AEB and PPT were evaluated by simulating a 1 g pre-crash braking scenario for 0.5 s, with and without AEB, for three different PPT force levels: 0, 300, and 600 N. The impact speed of 80 km/h was reduced to 69 km/h by AEB. When neither system was activated, the predicted risk for an occupant to sustain two or more fractured ribs (NFR2+) was 100% for both 45- and 65-year-old male occupants. The risks were reduced when the AEB was activated, particularly for the 45-year-old occupant. When the AEB was activated, the risks of concussion and rib fractures were reduced; upper neck tension forces, pelvis Anterior Superior Iliac Spine (ASIS) forces, and lower extremity forces were also reduced. Increasing the PPT forces reduced the rib fracture risk further (to about 48% for a 45-year-old occupant with 600 N PPT force). The reduced speed due to AEB resulted in a lower concussion risk (from 71.3% to 31%). However, the concussion risk increased slightly with increased PPT forces.
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| 2. |
- Olleja, Pierluigi, 1995, et al.
(författare)
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Can non-crash naturalistic driving data be an alternative to crash data for use in virtual assessment of the safety performance of automated emergency braking systems?
- 2022
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Ingår i: Journal of Safety Research. - : Elsevier BV. - 0022-4375. ; 83, s. 139-151
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Developers of in-vehicle safety systems need to have data allowing them to identify traffic safety issues and to estimate the benefit of the systems in the region where it is to be used, before they are deployed on-road. Developers typically want in-depth crash data. However, such data are often not available. There is a need to identify and validate complementary data sources that can complement in-depth crash data, such as Naturalistic Driving Data (NDD). However, few crashes are found in such data. This paper investigates how rear-end crashes that are artificially generated from two different sources of non-crash NDD (highD and SHRP2) compare to rear-end in-depth crash data (GIDAS). Method: Crash characteristics and the performance of two conceptual automated emergency braking (AEB) systems were obtained through virtual simulations – simulating the time-series crash data from each data source. Results: Results show substantial differences in the estimated impact speeds between the artificially generated crashes based on both sources of NDD, and the in-depth crash data; both with and without AEB systems. Scenario types also differed substantially, where the NDD have many fewer scenarios where the following-vehicle is not following the lead vehicle, but instead catches-up at high speed. However, crashes based on NDD near-crashes show similar pre-crash criticality (time-to-collision) to in-depth crash data. Conclusions: If crashes based on near-crashes are to be used in the design and assessment of preventive safety systems, it has to be done with great care, and crashes created purely from small amounts of everyday driving NDD are not of much use in such assessment. Practical applications: Researchers and developers of in-vehicle safety systems can use the results from this study: (a) when deciding which data to use for virtual safety assessment of such systems, and (b) to understand the limitations of NDD.
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| 3. |
- Puthan Pisharam, Pradeep, 1983, et al.
(författare)
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Characterizing future crashes on Indian roads using counterfactual simulations of pre-crash vehicle safety technologies
- 2022
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Ingår i: IATSS Research. - : Elsevier BV. - 0386-1112. ; 46:4, s. 479-491
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Tidskriftsartikel (refereegranskat)abstract
- India's national road crash statistics indicate a continuing increase in casualties. Pre-crash safety technologies are effective in high-income countries, but it is unclear how these will perform in India and which crash types will remain after their implementation. The study objective was to predict and characterize the crashes resulting in moderate or more-severe injuries (Maximum Abbreviated Injury Scale 2 or above: MAIS2+) that remain on Indian roads after 22 pre-crash safety technologies have been implemented in all cars, heavy vehicles (buses and trucks), and Powered Two-Wheelers (PTW). Two deterministic rulesets (one optimistic and one conservative) were modeled for each of the pre-crash safety technologies. Each rule was designed and tuned to the functionality of one technology. The data were obtained from the Road Accident Sampling System India (RASSI) database. In addition to the effectiveness of each technology alone, the combined effectiveness of all technologies was estimated. Further, the characteristics of those crashes that none of the technologies would have avoided were determined. Rear-end-specific Autonomous Emergency Braking (AEB REAR-END) and Electronic Stability Control (ESC) installed in cars and heavy vehicles reduced MAIS2+ crashes the most. Crashes between PTWs and cars were significantly reduced by a rear-end-specific AEB installed in the cars. A pedestrian-specific AEB (AEB-PED) in cars and heavy vehicles was also shown to be effective. The only pre-crash safety technology in PTWs that was included, Antilock Braking Systems (ABS), reduced overall PTW crash involvement, but only reduced PTW-to-pedestrian crashes marginally. The largest proportion of remaining crashes were those that involved PTWs, indicating that PTW safety will remain a concern in future.
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