An in-depth study of abdominal injuries sustained by car occupants in frontal crashes

Currently, neither abdominal injury risk nor rear seat passenger safety is assessed in European frontal crash testing. The objective of this study was to provide real world in-depth analysis of the factors related to abdominal injury for belted front and rear seat occupants in frontal crashes. Rear occupants were significantly more at risk of AIS 2+ and 3+ abdominal injury, followed by front seat passengers and then drivers. This was still the case even after controlling for occupant age. Increasing age was separately identified as a factor related to increased abdominal injury risk in all seating positions.One exception to this trend concerned rear seated 15 to 19 year olds who sustained moderate to serious abdominal injury at almost the same rate as rear occupants aged 65+.No strong associationwas seenbetween AIS 2+ abdominal injury rates andgender. The majority of occupant body mass indices ranged from underweight to obese. Across that range, the AIS 2+ abdominal injury rates were very similar but a small number of very obese and extremely obese occupants outside of the range did exhibit noticeably higher rates.An analysis of variance in the rate of AIS 2+ abdominal injury with different restraint systems showed that simple belt systems,as used by most rear seat passengers, were the least protective. Increasing sophistication of the restraint system was related to lower rates of injury. The ANOVA also confirmed occupant age and crashseverity as highly associated with abdominal injury risk. The most frequently injured abdominal organs for front seat occupants were the liver and spleen. Abdominal injury patterns for rear seat passengers were very different. While they also sustained significant injuries to solid organs, their rates of injury to the hollow organs (jejunum-ileum, mesentary, colon) were far higher even though the rate of fracture of two or more ribs did not differ significantly between seat positions. These results have implications for the design of restraint systems, particularly in relation to the occurrence of abdominal injury. They also raise issues of crash protection for older occupants as well as the protection afforded in different seating positions. ©Annals of Advances in Automotive Medicine

The design of category N3 vehicles for improved driver direct vision

Previous research has shown that existing Category N3 vehicle designs exhibit considerable direct vision blind spots in front of and to the near (passenger) side of the vehicle. This research explores the potential to reduce these blind spots through changes to vehicle geometry made possible by the proposed increase to vehicle length. Using a concept vehicle designed in a project performed by FKA this research evaluates the direct vision afforded to the driver against a baseline DAF XF 105 and a range of iterations of the FKA concept to explore improvements to vision. The analyses are performed using a 3D projection technique in the SAMMIE digital human modelling system. This allows the vehicle concepts to be populated with representative drivers and visual targets including vulnerable road users in the form of pedestrians and cyclists and a typical Category M1 vehicle (a passenger car). The analysis has shown that these blind spots can be improved for the specific tests that have been performed in this research by the FKA concept and the iterations of the concept that have been produced by the LDS team. When compared to the baseline vehicle the original FKA concept improves direct vision to vulnerable road users located at the centre of the vehicle front as the extended front effectively pushes the visual targets further away from the front of the vehicle allowing them to be seen. The visibility to the two front corners of the FKA concept and the lateral visibility through the driver and passenger doors remain problematic. The first iteration of the FKA concept reduces obscuration through the design of a compact instrument panel similar to those used in bus and coach designs. This iteration also improves direct vision to the near side and front nearside corner of the vehicle through the use of additional glazed areas. The visibility of the offside front corner is still problematic. The second iteration of the FKA concept is a modified version of the first iteration with a reduction in the cab height of the vehicle by 230mm. This results in the most successful concept analysed, with good direct vision of all of the visual targets that have been defined in the research project. This reduction in height is possible with current vehicles but would result in a vehicle with reduced off road capabilities due to a reduction in ground clearance. The third iteration of the FKA concept explored the potential of a central driving position. This provides advantages to direct vision through improved lateral visibility at the original height of the concept vehicle. However, this iteration also introduces new direct vision issues. The project has shown that the potential to extend the front of category N3 vehicles to include aerodynamic features has some benefit in terms of improved direct vision for the design that has been analysed, but that more radical design solutions, such as lowering the vehicle cab, and adding glazed areas to the doors and below the windscreen bottom edge provide more effective solutions to the direct vision problem

Time-to-collision analysis of pedestrian and pedal-cycle accidents for the development of autonomous emergency braking systems

The aim of this study was to describe the position of pedestrians and pedal cyclists relative to the striking vehicle in the three seconds before impact. This information is essential for the development of e ective autonomous emergency braking systems and relevant test conditions for consumer ratings. The UK RAIDS-OTS study provided 175 pedestrian and 127 pedal-cycle cases based on in-depth, at-scene investigations of a representative sample of accidents in 2000–2010. Pedal cyclists were scattered laterally more widely than pedestrians (90% of cyclists within around 80 degrees compared to 20 degrees for pedestrians), however their distance from the striking vehicle in the seconds before impact was no greater (90% of cyclists within 42 metres at three seconds compared to 50 metres for pedestrians). This data is consistent with a greater involvement of slow moving vehicles in cycle accidents. The implication of the results is that AEB systems for cyclists require almost complete 180 degree side-to-side vision but do not need a longer distance range than for pedestrians

FESTA. D2.4 Data analysis and modelling

The chapter of the handbook and the deliverable on data analysis will provide guidance and general principles for - pre-testing to check the usability of the system and the feasibility of the evaluation process, - controlling the consistency of the chain and the precision with different sampling schemes, - modelling the impact for each indicators and for an integrated evaluation including a systemic and multidisciplinary interpretation of the effects, - integrating and controlling the quality of space-time data from various sources (numerical, video, questionnaires), - selecting the appropriate statistical techniques for data processing, PI estimation and hypothesis testing in accordance to the list of indicators and experimental design, - scaling up from experimental data and identified models to population and network level. Experimentalists stress the role and importance of a preliminary field test in FOT. Three main objectives have been defined to make a preliminary diagnosis of usability of the systems and to check the relevance and feasibility of the evaluation process. These preliminary tests are very important for the practical deployment of the FOT as well as for the overall scientific evaluation process. Recommendations about the monitoring of local and global consistency of the chain of operations from the database extraction to the hypothesis testing are given, especially to ensure the validation of the calculation of the Performance indicators. Integration of the outputs of the different analysis and hypothesis testing requires a kind of meta-model and the competences of a multidisciplinary evaluation team, specially for interpretation of the system impact and secondary effects (behavioural adaptation, learning process, long-term retroaction, …). In cooperation with WP2.2, methods for data quality control have been defined. Four types of checks have been defined to complement the information of the data base in order to prepare the data for the analysis. Statistical methods have been described for three steps of the chain: data processing, PI calculation and hypothesis testing. They belong either to exploratory data analysis or to inferential analysis. Special attention has been given to the precision of the estimates of the effects or impacts of the system on the Performance indicators by stressing the importance of controlled randomisation and application of mixed regression models. Scaling-up relies upon the potential to extrapolate from the PIs to estimates of the impact at an aggregated level. Three approaches have been defined to carry out the scaling up process from direct estimations to simulation models with the related assumptions. Models and methodologies for scaling up results on traffic flow, environmental effects (e.g. PM10, CO2, Noise emissions in db) and traffic safety have been collected

Guidelines for data quality assurance

The UDRIVE project aims to colle ct on the region of 100,000 hours of naturalistic driving data in order to support the analysis related to o Crash causation, crash risk and normal driving o Distraction and inattention o Vulnerable road users o Driving styles related to eco-driving This document contains information relevant to data quality assurance for the UDRIVE project. Good quality data is a fundamental requirement for good quality analysis and data quality should be considered at all stages of the data processing chain: o Data Acquisition System Installation o During data collection o Database management • Data preprocessing • Data post-processing In order to deliver high quality data as an outcome from the UDRIVE project actions have been undertaken at each stage of the chain, following generic guidelines for data quality

The definition, production and validation of the direct vision standard (DVS) for HGVS. Final Report for TfL review

This report presents research performed by Loughborough Design School (LDS) on behalf of Transport for London. The research has been conducted against a background of over representation of heavy goods vehicles (HGVs) being involved in road traffic accidents with vulnerable road users (VRUs) where ‘failed to look properly’ and ‘vehicle blind-spot’ are often reported as the main casual factors in the accident data. Previous work by LDS on driver’s vision from HGVs has identified the need to reduce reliance on indirect vision via mirrors through the specification of a direct vision standard (DVS) for HGVs. Recent work commissioned by TfL and performed by the Transport Research Laboratory (TRL) resulted in a draft DVS. This draft DVS has been evaluated and reworked by the LDS team to produce a viable and robust method to quantify direct vision performance of an HGV together with a means to rate that vision performance against a star rating standard. Throughout this process significant stakeholder consultation has been used to support the development of the DVS. A total of 27 vehicles representing the majority of the current Euro 6 N3 HGV fleet have been modelled in CAD. Where data were available these have been mounted at the highest, lowest and most sold heights to produce a sample of 54 test vehicles. A methodology has been developed that utilises volumetric projection of the field of view of the driver via the windows in the cab. This projection is then intersected with an assessment volume. The result is a volumetric representation of the space around a HGV cab that the driver can see to the front, driver and passenger sides. The volume of this space can be calculated to provide a rating of direct vision performance. An iterative design process was followed that explored different specifications of the assessment zone around the cab, factoring in the collision data with VRUs and the use of weightings to prioritise what needs to be seen. Two weighting schemes were evaluated one prioritising the volumes vertically, recognising the importance of being able to see closer to the ground, and a second prioritising the volumes directionally to address the prevalence of accidents being greater to the front and passenger side when compared to the driver’s side. The final specification of the volumetric assessment consists of a single, unweighted zone around the cab, informed by the current coverage of mirrors specified in UNECE regulation 46. This was done to foster direct vision that aims to remove the reliance on mirrors and thus should focus on providing direct vision of the areas currently covered by mirrors. The vehicle sample was then evaluated for its performance using this assessment, providing a volumetric score for each vehicle. These volumetric scores were then quantified by correlating them with a VRU simulation. Thirteen 5th %ile Italian female VRUs were placed around the vehicle and moved laterally to a point at which their head and shoulders could be seen. This served to provide context for the volumetric results such that a particular volume could be equated to an average distance at which the small adult could be seen. Furthermore, the VRU simulations provided a means to translate the volumetric performance into star ratings. Four star rating specifications were produced following an absolute (based on risk/safety) and a relative (based on the performance of the current fleet) approach. For both absolute and relative two iterations were proposed: 1. the VRU simulation distances were used to establish a threshold value, 2. the median volumetric result was used to establish a threshold value. The final option taken forwards used the VRU simulation distances for a 5th %ile Italian female to define the 1 star boundary. Vehicles able to provide direct vision of the VRUs at an average of <2m to the front, <4.5m to the passenger side and <0.6m to the driver’s side achieved a star rating 1 star or above. All others achieved a rating of zero star. Star ratings from 1 to 5 star were sub divided equally. The final result consists of three main outcomes: The definition, production and validation of the direct vision standard (DVS) for HGVs December 2018 Transport for London 4 Loughborough Design School © 1. A robust, repeatable and validated method for the volumetric analysis of direct vision performance using a CAD based process 2. A process to map a volumetric score for a given vehicle onto the 5 star rating scale to produce a DVS rating for any vehicle. 3. Star ratings for the majority of the Euro 6 N3/N3G HGV fleet showing that of the 41 configurations analysed, two vehicles are rated 5 star, no vehicles are rated 4 star, five vehicles are able to achieve 3 star, three vehicles are able to achieve 2 star, and six vehicles are able to achieve 1 star, the remainder 25 vehicles were rated as zero star

Collection, analysis and use of in-depth road accident and exposure data

Collection, analysis and use of in-depth road accident and exposure dat