Predicting occupant head displacements in evasive maneuvers; tuning and comparison of a rotational based and a translational based neck muscle controller.

Real-life car crashes are often preceded by an evasive maneuver, which can alter the occupant posture and muscle state. To simulate the occupant response in such maneuvers, human body models (HBMs) with active muscles have been developed. The aim of this study was to implement an omni-directional rotational head-neck muscle controller in the SAFER HBM and compare the bio-fidelity of the HBM with a rotational controller to the HBM with a translational controller, in simulations of evasive maneuvers.

Comparison of child and ATD belt fit and posture on belt-positioning boosters during self-selected, holding device, and nominal conditions.

Objective: Pediatric anthropomorphic test devices (ATDs) are important tools for the assessment of child occupant protection and should represent realistic child belt fit and posture on belt-positioning boosters. Previous comparisons have been made to children in either self-selected or nominal postural conditions. This study compares belt fit and postural measurements between pediatric ATDs and a single cohort of children assuming different postures on boosters: self-selected, holding a portable electronic device, and nominal.

Personalization of human body models and beyond via image registration.

Finite element human body models (HBMs) are becoming increasingly important numerical tools for traffic safety. Developing a validated and reliable HBM from the start requires integrated efforts and continues to be a challenging task. Mesh morphing is an efficient technique to generate personalized HBMs accounting for individual anatomy once a baseline model has been developed.

Head injury criteria assessment using head kinematics from crash tests and accident reconstructions.

Objective: The aim of this study was to assess head injury criteria based on their correlation to brain strain in a Finite Element (FE) head model (the KTH Royal Institute of Technology model), by simulation of head kinematics data from frontal and side crash tests with Anthropomorphic Test Devices (ATDs), and from Human Body Model (HBM) accident reconstructions.

Methods: Six Degrees of Freedom (DoF) head kinematic data was extracted from 221 crash tests, consisting of frontal impacts with the THOR-50M ATD, near-side and far-side impacts with the WorldSID-50M ATD, and from 19 FE HBM accident reconstructions. The head injury criteria HIC, HIP, BrIC, UBrIC, DAMAGE and CIBIC were calculated, and FE head model simulations were conducted using the six DoF kinematics data.

Description of same-direction car-to-bicycle crash scenarios using real-world data from Sweden, Germany, and a global crash database.

The overall number of traffic crashes is decreasing, but the number of crashes incurring cyclist injuries is not decreasing at the same pace. Of all car-to-bicycle crashes, same-direction crashes are among the ones with the highest risk of a serious-to-fatal injury. In this study, car-to-bicycle crashes occurring when a passenger car and a bicycle are both traveling in the same direction and on the same road (without a physically separated lane) from four different real-world crash databases were investigated.

Computational modeling of driver pre-crash brake response, with and without off-road glances: Parameterization using real-world crashes and near-crashes.

When faced with an imminent collision threat, human vehicle drivers respond with braking in a manner which is stereotypical, yet modulated in complex ways by many factors, including the specific traffic situation and past driver eye movements. A computational model capturing these phenomena would have high applied value, for example in virtual vehicle safety testing methods, but existing models are either simplistic or not sufficiently validated. This paper extends an existing quantitative driver model for initiation and modulation of pre-crash brake response, to handle off-road glance behavior.

Detection and response to critical lead vehicle deceleration events with peripheral vision: Glance response times are independent of visual eccentricity.

Studies show high correlations between drivers' off-road glance duration or pattern and the frequency of crashes. Understanding drivers' use of peripheral vision to detect and react to threats is essential to modelling driver behavior and, eventually, preventing crashes caused by visual distraction. A between-group experiment with 83 participants was conducted in a high-fidelity driving simulator.

Booster cushion design effects on child occupant kinematics and loading assessed using the PIPER 6-year-old HBM and the Q10 ATD in frontal impacts.

Objective: Our objective was to study the effect on child occupant kinematics and loading by differences in booster cushion designs and attachment in a frontal impact.

Methods: Three different booster cushion designs were exposed to a frontal impact in vehicle rear seat interiors. The boosters were selected based on their difference in shape, stiffness, and guiding loop design.

The impact of driver sleepiness on fixation-related brain potentials.

The effects of driver sleepiness are often quantified as deteriorated driving performance, increased blink durations and high levels of subjective sleepiness. Driver sleepiness has also been associated with increasing levels of electroencephalogram (EEG) power, especially in the alpha range. The present exploratory study investigated a new measure of driver sleepiness, the EEG fixation-related lambda response.

A farewell to brake reaction times? Kinematics-dependent brake response in naturalistic rear-end emergencies.

Driver braking behavior was analyzed using time-series recordings from naturalistic rear-end conflicts (116 crashes and 241 near-crashes), including events with and without visual distraction among drivers of cars, heavy trucks, and buses. A simple piecewise linear model could be successfully fitted, per event, to the observed driver decelerations, allowing a detailed elucidation of when drivers initiated braking and how they controlled it. Most notably, it was found that, across vehicle types, driver braking behavior was strongly dependent on the urgency of the given rear-end scenario's kinematics, quantified in terms of visual looming of the lead vehicle on the driver's retina.

Driving context influences drivers' decision to engage in visual-manual phone tasks: Evidence from a naturalistic driving study.

Introduction: Visual-manual (VM) phone tasks (i.e., texting, dialing, reading) are associated with an increased crash/near-crash risk.

Safe mobility for elderly drivers--considerations based on expert and self-assessment.

To further understand the needs of the growing population of elderly drivers and create solutions for safe mobility it is important to understand the driving scenarios and aspects in day to day traffic that may be of challenge for this group. More so, individual differences in how drivers perceive their own driving ability may have an effect on how individuals limit their mobility and/or increase their exposure to risk situations, with a potential negative effect on safety. In this study two sets of assessments have been used in order to identify scenarios and aspects needing consideration in creating safe mobility for elderly drivers; an expert assessment using on-road driving together with assessments through semi structured in-depth interviews.

What can the drivers' own description from combined sources provide in an analysis of driver distraction and low vigilance in accident situations?

Accident data play an important role in vehicle safety development. Accident data sources are generally limited in terms of how much information is provided on driver states and behaviour prior to an accident. However, the precise limitations vary between databases, due to differences in analysis focus and data collection procedures between organisations.

Nonresponse analysis and adjustment in a mail survey on car accidents.

Statistical accident data plays an important role for traffic safety development involving the road system, vehicle design, and driver education. Vehicle manufacturers use data from accident mail surveys as an integral part of the product development process. Low response rates has, however, lead to concerns on whether estimates from a mail survey can be trusted as a source for making strategic decisions.

Real World Data Driven Evolution of Volvo Cars' Side Impact Protection Systems and their Effectiveness.

This study analyses the outcome of the continuous improved occupant protection over the last two decades for front seat near side occupants in side impacts based on a real world driven working process. The effectiveness of four generations of improved side impact protection are calculated based on data from Volvo's statistical accident database of Volvo Cars in Sweden. Generation I includes vehicles with a new structural and interior concept (SIPS).

WHIPS (Volvo cars' Whiplash Protection System)-the development and real-world performance.

Objectives: Present the performance of WHIPS and identify possible next steps of soft tissue neck injury reduction potentials, based on rear-end real-world crash data.

Methods: Front-seat occupants (above 14 years of age) have been analyzed regarding influencing factors on reported incidences of soft tissue neck injuries. The outcome of 1858 occupants in cars equipped with WHIPS and 663 occupants in Volvo cars of model year 1999 without WHIPS are studied with respect to WHIPS injury-reducing effect for different impact severities and injury durations.