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Objective: The objective of this study was to examine the influence of bicycle design and speed on the head impact when suffering from a single-bicycle crash, and the possibility to study this using crash tests. Methods: Simulations of single-bicycle crashes were performed in the VTI crash safety laboratory. Two bicycle crash scenarios were simulated: “a sudden stop” and “sideways dislocation of the front wheel”; using four different bicycle types: a “lady’s bicycle”, a commuter bicycle, a recumbent bicycle and a pedelec; at two speeds: 15 and 25 km/h. In addition, sideway falls were performed with the bicycles standing still. All tests were done with a Hybrid II 50th percentile crash test dummy placed in the saddle of the bicycles, with acceleration measurements in the head. Results: The crash tests showed that a sudden stop, e.g. a stick or bag in the front wheel, will result in a falling motion over the handle bars causing a forceful head impact while a sideways dislocation of the front wheel will result in a falling motion to the side causing a more moderate head impact. The falling motion varies between the different bicycle types depending on crash test scenario and speed. The pedelec had a clearly different falling motion from the other bicycle types, especially at a sudden stop. Conclusions: The study implies that it is possible to examine single-bicycle crashes using crash tests, even though the setup is sensitive to minor input differences and the random variation in the resulting head impact values can be large. Sideway falls with the bicycles standing still were easier to perform with a good repeatability and indicated an influence of seating height on the head impact.

This paper presents a driving simulator study on driving behavior in a critical head-on collision scenario. The study aims at providing basic understanding of driver responses to headlight and horn warning coming from another vehicle a time critical situation. In total, 48 participants drove 30 km. During the drive participants performed a secondary task, announced by a vibration in the seat. At the time of the secondary task the own vehicle was directed into the opposing lane where oncoming simulated vehicles issued a light and/or sound warnings to get the drivers attention. An additional purpose of the study was to examine if the warning coming from the other vehicle has a different effect on persons with a hearing loss. A possible application for this type of warnings is the implementation of a system for automatic activation. Systems for automatic activation of brakes and steering are currently entering the market. These systems use proximity sensors to monitor the state of surrounding road users. Depending on the specific situation the effort/possibility to avoid or mitigate an accident may differ significantly between the principle road users of a pending collision, e.g. one road user (1) may easily avoid a collision while another (2) may not be able to do so. The only possibility for the second road user (2) to avoid a collision in such a situation is to issue a warning to the first (1), so that he/she may take evasive actions. Connecting the horn and the headlight to already existing sensor system, for automatic warning activation, is a cost effective means to provide such a warning. The warnings, could of course, also be triggered manually by the driver. The results indicate that a driver who receives a warning from the oncoming vehicle responds faster to avoid the pending frontal collision. The most effective warning was the combination of horn and headlight. A majority of the participants where positive to the notion of an automated system to provide this type of warning (n=41). No significant difference in the behavior between the groups with and without hearing loss was found in this study. Principal other vehicle warning

Syftet med denna studie är att komplettera ”Olycksriskmodellen” (inom Tema Vintermodell) med olycksrisk respektive konsekvens för olika olyckstyper, för att kunna beräkna kostnaderna för olyckor på is- och snöväglag. Olycksrisken har vi beräknat genom att dividera antalet olyckor med trafikarbetet, för vintrarna 1993/1994 t.o.m. 1996/1997. Olycksdata har vi hämtat ur Vägverkets informationssystem för trafiksäkerhet, VITS. Där är olyckorna kodade efter olyckstyp, som till viss del beskriver händelseförloppet i respektive olycka. I den här studien har vi grupperat olyckorna i fyra olyckstyper: singelolyckor, mötesolyckor, upphinnandeolyckor och övriga olyckor. För samtliga olyckstyper är olycksrisken högre på is/-snöväglag relativt den på torr barmark. Mötesolyckorna och singelolyckorna har de högsta relativa olyckskvoterna med olycksrisker som är mer än tio gånger högre på is- och snöväglag. För singelolyckorna är det tunn is/rimfrost som är huvudorsaken till denna stora ökning, medan de andra is-/snöväglagen har en minst lika stor betydelse för mötesolyckorna. Konsekvenserna blir generellt sett allvarligare vid mötesolyckor på is-/snöväglag jämfört med på torr barmark. För singelolyckorna blir de tvärtom lindrigare. Konsekvenserna beräknade vi genom att dividera antalet dödade och svårt skadade respektive lindrigt skadade med det totala antalet olyckor. För dessa beräkningar har olycksdata för alla vintrar under hela 1990-talet använts. The aim of this study is to augment the Accident Risk Model (within the Winter Model) with accident risk and the consequences of different types of accident, in order that the costs of accidents in icy and snowy road conditions may be calculated. We have calculated the accident risk by dividing the nutuber of accidents by vehicle mileage for the winters of 1993/1994 through 1996/1997. In this study, we have grouped accidents into four types: single-vehicle accidents, head-on collisions, rear-end collisions and other accidents. For all accident types the accident risk is higher on icy and snowy roads than on dry bare roads. Head-on collisions and single-vehicle accidents have the highest relative accident rates, with accident risks that are more than ten times higher in snowy and icy road conditions. For single-vehicle accidents, it is the thin ice/hoar frost that is the main cause of this great increase. Generally, the consequences of head-on collisions are more serious on roads with snow and ice than on dry bare roads in the wintertime, while for single-vehicle accidents the consequences are less serious. We have calculated the consequences by dividing the nutuber killed, severely injured and slightly injured by the total number of accidents. For these calculations, accident data for all winters during the whole of the 1990s have been used.

When small children travel in minibuses, during for example daycare transports, they seldom have adequate protection in terms of crash safety. To be sufficiently protected the child should travel in a rearward facing child restraint system (CRS). The possibility to use such a seat is unfortunately accompanied by several problems. The main issues are that it can be hard and time consuming to secure a conventional child restraint system and that the available space in a minibus is limited. The task is therefore to develop a new system that makes it possible to easily secure the child restraint system in the bus, without compromising the space and mobility of the other passengers. This is done by using the newly developed anchorage system, Isofix, in combination with a small stand that replaces the bus seat. Testing and evaluation of the developed system shows that it is achievable with a simple design to rapid and effortlessly secure a rearward facing child restraint system in a minibus, and thus giving small children the highest possible level of safety.