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. The focus was on analyzing pre-crash factors such as speed and light conditions, as well as other factors such as impact configurations and cyclist injuries. Three main crash scenarios were identified among the crashes that were studied. The most common one (comprising 65%) was CS1: "continued same-direction" with no intention of turning by either road user. The other two scenarios were CS2: "the bicycle crosses the vehicle's path by turning" (16%) and CS3: "the car crosses the bicycle's path by turning" (19%). The CS1 crashes were divided into three overtaking phases: approaching and steering, passing, and returning, representing 42-44%, 41-44%, and 12-17%, respectively, of the CS1 scenario. The three crash scenarios varied in car and bicycle speeds, road type, and weather and light conditions, as well as in impact points and cyclist injuries. The analysis of different same-direction crash scenarios and overtaking phases in this study offers a novel view of same-direction crashes, providing relevant information for the design of methods for the evaluation of crash avoidance and injury mitigation measures for these scenarios.

How thirty years of focused safety development has influenced injury outcome in volvo cars.

ABSTRACT This study points out how thirty years of focused safety development has produced a steady decrease in injury rates in car crashes, strongly influenced by a well-structured process. An important part of this process is the knowledge gained by accident research based on collection of data from real world crashes, and the feedback of this research into development work. Statistical analysis shows that the MAIS 2+ injury rate for the most recent car models has decreased by two-thirds compared to the rate for the oldest car models. Calculation of the effect of specific development steps will be given as examples.

WHIPS--Volvo's Whiplash Protection Study.

Whiplash associated disorders (WAD) resulting from rear end car impacts are an increasing problem. WAD are usually not life threatening, but are one of the most important injury categories with regard to long-term consequences. This paper is a review of Volvo's Whiplash Protection Study (WHIPS), which is the result of more than ten years of concentrated research efforts in the area of neck injuries in car collisions, with the focus on rear end car impacts. The study follows the whole chain from accident research to the development of a seat for increased protection against WAD. Results from Volvo's accident research are summarized. Existing biomechanical knowledge regarding possible injury mechanisms are presented and discussed. Based on the interpretation of accident research and biomechanical knowledge, guidelines for improved protection against WAD in rear end impacts are presented. Requirements and test methods based on the guidelines are explained. An important part of the study is a new rear end impact dummy, BioRID. Test results using the new dummy are presented. Finally, the paper explains the design of a new seat for increased WAD protection, the WHIPS-seat. Results from the accident research and biomechanical research emphasize the importance of considering the whole spine of the occupant and, accordingly, the whole seat when addressing WAD in rear end impacts, with a particular focus on low and moderate impact severity. Low and moderate impact severity crashes should be focused. Also important to consider are the individual differences between occupants, the seating position and the variety of seating postures. All results, including sub-system testing, mathematical modeling, sled testing, as well as geometrical parameters show that the WHIPS-seat will have considerable potential for offering increased protection against WAD in rear end impacts.