The traffic environment can be characterised as a technical system in which users interact with system objectives to quickly and safely move from one point to another. To achieve the system objectives it is necessary for the system to be easy to understand and comply with. The purpose of the present study is to examine professional driver's understanding of the rule governing giving right of way to pedestrians at unguarded pedestrian crossings as well as their compliance with maximum permitted speeds. One hundred and ninety six professionals from different transport companies located in Sweden participated in the study. The main results showed that the professional drivers’ understanding of the rule governing giving right of way to pedestrians was quite insufficient, even though, they had considerable confidence in their understanding of that rule. Furthermore, their general attitude was to comply with the maximum speed permitted, even though, they often exceeded it.

The aim of this paper is to describe an ongoing project with the aim of improving safety in an organization working with maintenance and development of the railway infrastructure in Sweden. The first sub goal was to investigate the Genta method, with 62 employees resulted in a description of these latent errors in the organization.eral Failure Types in the organization. Seminars and interviews, based on the Tripod Del Recommendations for an improvement toward a safety culture was suggested, action plans were formulated and, in some cases, implemented. A follow up study is planned in a two year perspective.

The purpose of this study was to gain a better understanding of driver’s perceptions of Head-Up Displays (HUD). Many HUD studies have been conducted but few have allowed drivers to test a HUD in their own vehicle, allowing them to choose the best HUD location for themselves. Forty participants drove their own vehicles using a portable HUD, testing different HUD locations and then rating it using the Technology Acceptance Model. The results showed that the HUD was rated as easy to use and the drivers intended to use it in continuation. The drivers wanted the HUD to be located outside of the traffic scene, either to the right, left or below their line of sight. These results give support for new HUD locations and for increased HUD implementation.

As more and more technology is added to the automobile interior it needs to be designed in a usable and efficient way: to facilitate safe driving. This paper reviews guidelines and visual design principles for automotive instrumentation. Guidelines were compiled, categorized and analysed in order to determine whether they were valid and usable for today’s design of information presentation in automobiles. By doing this, contradictory guidelines and gaps in knowledge were identified and discussed. However, there appeared a consensus within the different guidelines of best practice, and many are still usable by designers today.

Visual warnings are used to help prevent drivers from making unnecessary mistakes, but if warnings are not noticed in time they are useless. Today warnings are most often placed in front of the driver and behind the steering wheel, but this may not be the most conducive location for all warnings. An unexpected warning can increase the risk for distraction, just as a poorly placed warning can, which, in turn, could decrease the driver's chances to react correctly for what is warned for. A dilemma for traffic safety experts is how to expand the ways warnings can be presented to the driver without negatively affecting driver performance. In this study a questionnaire, 142 respondents, was used to find out driver's perception to in-vehicle warnings and where they preferred those to be found; in a head-up display (HUD), head-down display (HDD), infotainment (IF), or in a center-stack (CS). Twenty respondents in a high fidelity fixed base simulator compared and evaluated how different warnings placements were responded to and how they affected normal driving in two different warning layouts. Ten respondents were simultaneously presented a warning in the HUD and HDD and ten in either the HUD, HDD, IF, or the CS. Response times (via focal vision), driving performance, and subjective responses were measured, which included measuring the cognitive workload with the Driving Activity Load Index (DALI). The results showed that the respondents of the HUD/HDD group almost exclusively used the HUD and all respondents stated that the HUD was best fitted for important warnings. However, more transparent groupings of warnings were requested as a separation of warnings based on their level of importance. Moreover, the drivers performed best when the warnings were presented in the HUD and IF locations

This study was designed to investigate effects of different display configuration designs. Nineteen drivers completed a driving simulator study designed to resemble normal driving. Driving performance, glance behaviour, physiological measures, and task completion times was measured for two display configuration designs both during driving only and during driving with a simple secondary task, which consisted of detection, and off-setting of presented warnings. The display configuration design with more centrally placed information, e. g. the HUD and HDD, had less detrimental effects on driving performance and glance behaviour. The physiological measures showed, however, no significant differences between display configuration designs.

The aim of this study was to investigate the effects of redundant driving information while conducting simple vs complex tasks via instructions presented simultaneously from the Head-Up Display (HUD) and Head Down Display (HDD) placements in normal driving conditions. Twenty respondents drove a fixed based high-fidelity driving simulator through 15km of light to moderate traffic in both rural and urban areas while responding to instructions. Ten respondents received ten warnings to respond to by pressing a button while the other ten respondents received ten instructions to conduct tasks in the center-stack area of the simulator. These tasks varied in difficulty from turn on CD player, to dial a given telephone number. Driving performance was measured via response time, gaze patterns, average speed, and maneuverability. Cognitive workload was assessed with the Driving Activity Load Index (DALI). The results showed that there were no significant differences between the baseline and experimental runs for the warnings due to the simple nature of the tasks while significant differences were found in the average speed and deviation from speed limit. The respondents rated the complex tasks as having a greater visual and temporal demand in relation to the simple tasks. The HUD was almost exclusively used by the respondents for driving information and stated that it was fitting for warnings and primary driver information.

The concern for mental overload from warnings has been considered over a longer period of time, even though; warnings continue to be added in vehicles. Both warnings and icons are being tested for understandability but perceptions of the importance of each specific warning and its placement in the driving compartment seems to have had lesser importance in research. Such as, too much visual information presented to the driver or confusing warnings has showed to cause overload and, hence, reduce the driver’s ability to perform safely. A dilemma the automobile industry is facing today is how to expand the ways visual information via warnings can be presented to the driver without increasing the cognitive workload, which, in turn, increases the risk for distraction. The aim of this study was to investigate the effects of warnings placement on the drivers’ ability to respond to them while maintaining safe driving in normal driving conditions. Twenty respondents drove a fixed based high fidelity driving simulator though 15km of light to moderate traffic in both rural and urban areas while responding to warnings. Ten respondents received warnings in both the head-up display (HUD) and head-down display (HDD) simultaneously while the other respondents received the same ten warnings in one of the four displays: HUD, HDD, infotainment display (IF), and center-stack display (CS) in the same traffic situations but in only one of the four placements at a time. The respondents’ response times to the warnings (via focal vision), their gaze patterns, average speed, maneuverability, and their own subjective responses were measured. The results showed that there were no significant differences between the baseline and experimental runs due to the simple nature of the tasks while significant differences were found in the response times regarding the four placement design. Warnings for serious failures and those pertaining to the vehicles mechanical operation were preferred to be placed in the HUD while warnings for maintenance and service along with reminders were chosen to be placed in the HDD. Response times and driving was perceived to be better when using the HUD while the CS was considered too far away to be looked at for warnings.