<p>Every year many people all over the world are killed and severely injured in road traffic accidents. Even though driving too fast is a behaviour well known to contribute to both the number and the outcome of these accidents, drivers are still speeding. The general aim of this thesis, and its five empirical studies, is therefore to further the knowledge about drivers speeding behaviour by using the theory of planned behaviour and the model underpinning the driver behaviour questionnaire as frames of reference. The behavioural data used is obtained from field trials with intelligent speed adaptation and the speed reducing potential of this system is also examined. The results show that attitude towards exceeding the speed limits, subjective norm, perceived behavioural control and moral norm from the theory of planned behaviour, but also violations and inattention errors from the model underpinning the driver behaviour questionnaire, can be used to predict drivers’ everyday speeding behaviour. These two models can also be combined in order to gain further knowledge about the causes of speeding. Identification of drivers’ beliefs about exceeding the speed limits gives further insight into the underlying cognitive foundation of their attitude, subjective norm and perceived behavioural control. This provides valuable information for future design of speed reducing measures. Regarding intelligent speed adaptation, the results show that the ISA speed-warning device greatly reduces the amount of time drivers spend above the speed limits, and to some extent also reduces their mean speeds, but that this effect decreases with time. Although the drivers are not totally satisfied with the experience of the ISA speed-warning device, they like the idea and can see its usefulness. As the device tested is a first generation ISA speed-warning device, further research has the potential to greatly improve the system.</p>

Every year many people all over the world are killed and severely injured in road traffic accidents. Even though driving too fast is a behaviour well known to contribute to both the number and the outcome of these accidents, drivers are still speeding. The general aim of this thesis, and its five empirical studies, is therefore to further the knowledge about drivers speeding behaviour by using the theory of planned behaviour and the model underpinning the driver behaviour questionnaire as frames of reference. The behavioural data used is obtained from field trials with intelligent speed adaptation and the speed reducing potential of this system is also examined. The results show that attitude towards exceeding the speed limits, subjective norm, perceived behavioural control and moral norm from the theory of planned behaviour, but also violations and inattention errors from the model underpinning the driver behaviour questionnaire, can be used to predict drivers’ everyday speeding behaviour. These two models can also be combined in order to gain further knowledge about the causes of speeding. Identification of drivers’ beliefs about exceeding the speed limits gives further insight into the underlying cognitive foundation of their attitude, subjective norm and perceived behavioural control. This provides valuable information for future design of speed reducing measures. Regarding intelligent speed adaptation, the results show that the ISA speed-warning device greatly reduces the amount of time drivers spend above the speed limits, and to some extent also reduces their mean speeds, but that this effect decreases with time. Although the drivers are not totally satisfied with the experience of the ISA speed-warning device, they like the idea and can see its usefulness. As the device tested is a first generation ISA speed-warning device, further research has the potential to greatly improve the system.

Neste trabalho foram estabelecidos os fundamentos metodológicos baseados na identificação dos fatores de risco, fatores de risco identificados, necessários na elaboração de campanhas de segurança viária, orientados pelas diretrizes estabelecidas no projeto CAST (Campaigns and Awareness-raising Strategies in Traffic Safety), o qual define a identificação do comportamento-problema gerador de acidentes como elemento essencial na definição do objetivo de cada campanha. Não havendo dados estatísticos consistentes e confiáveis dos quais seja possível extrair esta informação, foi necessário identificar os fatores comportamentais que estão na origem de atos inseguros e que devem ser prioritários na elaboração de campanhas de segurança viária. Para o efeito, foi necessário estabelecer uma metodologia que envolveu a utilização de diferentes instrumentos de coleta de dados com o objetivo de identificar os comportamentos-problema, assim como outros fatores relacionados à infraestrutura e ao meio ambiente que poderiam induzir esses comportamentos. Esta metodologia envolveu a aplicação de Grupos Focais que orientaram a elaboração de um questionário voltado para a identificação dos fatores de risco do sistema viário, comportamentos de risco e opiniões relacionados com os tipos de mensagens de campanhas. Este questionário foi posteriormente aplicado a uma amostra de condutores, juntamente com o DBQ &#8211; Driver Behaviour Questionnaire, este orientado para a identificação de comportamentos de risco de cada inquirido. A associação desses dois instrumentos permitiu a identificação de fatores de risco no sistema viário, assim como comportamentais de risco habituais e as preferências dos inquiridos sobre tipos e mensagens de campanhas, bem como meios de mídia. A análise estatística dos dados coletados permitiu identificar os seguintes fatores de risco relacionados à via: (1) más condições da infraestrutura da via, (2) más condições de sinalização, (3) más condições dos veículos que trafegam pelas vias, e (4) interação principalmente com pedestres. Foram ainda identificadas as suas opiniões relativamente a comportamentos-problema dos demais usuários do sistema viário, destacando-se os seguintes fatores: (1) sono, (2) bebidas, (3) drogas e (4) mensagens de texto. Quanto à importância das campanhas, os inquiridos consideram que elas devem: (1) ser dirigidas aos fatores de risco identificados, (2) estar associadas a outras ações como fiscalização e (3) seus resultados devem ser divulgados pelos órgãos de governo. Finalmente, acerca das mensagens das campanhas e tipos de mídia utilizados, os inquiridos consideraram que as mensagens devem: (1) utilizar laços afetivos, (2) ser mais impactantes, (3) conter cenas reais, (4) ter finalidade educativa; e as mídias mais adequadas seriam: (1) televisão, (2) internet (com ênfase às redes sociais) e (3) painéis de mensagens variáveis. Quanto ao questionário DBQ, foram identificados sete fatores comportamentais dos próprios inquiridos com maior peso e relação com atos inseguros: (1) Baixo nível de aptidão, (2) Infração, (3) Distração/Inatenção, (4) Condução agressiva, (5) Baixa consciência da situação, (6) Estresse e (7) Adaptação Comportamental. Esses fatores representam os tópicos prioritários que devem ser trabalhados em futuras campanhas. / This research established the methodological principles based on the identification of risk factors necessary for elaboration road safety campaigns, following the guidelines recommended by the CAST (Campaigns and Awareness-raising Strategies in Traffic Safety) project, which defines the identification of main problem behaviors generating accidents as an essential element in the definition of each campaign goal. Since there is no consistent and reliable statistical data proveding this information, it was necessary to identify the behavioral factors that originate unsafe acts and that should be priority in road safety campaigns. In order to achieve this result, it was necessary to establish a methodology involving the use of different data collection tools with the intention of identifying the problem behaviors, as well as other factors related to the infrastructure and environment capable to induce these behaviors. This methodology involved Focus Groups application that directed the elaboration of a questionnaire aiming at a identifing road system risk factors, risky behaviors and opinions regarding the types of campaigns messages. This questionnaire was further applied to a drivers\' sample, together with the DBQ Driver Behavior Questionnaire, which was directed to the identification of risky behaviors of each respondent. The association between these two instruments enabled the identification of road system risk factors, as well as common risky behaviors and the respondents\' preferences about the types of campaign messages and media means. The statistical analysis of the collected data enabled the identification of the following risk factors related to the road system: (1) poor road infrastructure conditions, (2) poor signing conditions, (3) poor vehicle conditions, and (4) interaction mainly with pedestrians. Opinions about problem-behaviors were also identified, stressing the following factors: (1) drowsiness, (2) drink and drive, (3) drugs and medication effects (4) texting driving. Concerning the campaigns importance, the respondents considered that they should: (1) be directed to identified risk factors, (2) be associated to other actions such as enforcement and (3) have its results published by the government entities. Finally, regarding the campaign messages and the used media types, the respondents considered that the messages should: (1) use affective anchors, (2) be more impactful, (3) contain real scenes, (4) have educative purpose; and the most adequate media would be: (1) television, (2) internet (with emphasis to the social networks) and (3) variable message panels. With respect to the DBQ questionnaire, seven behavioral factors based on the respondents own experience were identified as more important and related to unsafe attitudes: (1) poor fitness to drive, (2) violations, (3) distraction/inattention, (4) aggressive driving, (5) poor situation awareness, (6) stress and (7) behavioural adaptation. These factors represented the priority topics that should be handled in future campaigns.

Neste trabalho foram estabelecidos os fundamentos metodológicos baseados na identificação dos fatores de risco, fatores de risco identificados, necessários na elaboração de campanhas de segurança viária, orientados pelas diretrizes estabelecidas no projeto CAST (Campaigns and Awareness-raising Strategies in Traffic Safety), o qual define a identificação do comportamento-problema gerador de acidentes como elemento essencial na definição do objetivo de cada campanha. Não havendo dados estatísticos consistentes e confiáveis dos quais seja possível extrair esta informação, foi necessário identificar os fatores comportamentais que estão na origem de atos inseguros e que devem ser prioritários na elaboração de campanhas de segurança viária. Para o efeito, foi necessário estabelecer uma metodologia que envolveu a utilização de diferentes instrumentos de coleta de dados com o objetivo de identificar os comportamentos-problema, assim como outros fatores relacionados à infraestrutura e ao meio ambiente que poderiam induzir esses comportamentos. Esta metodologia envolveu a aplicação de Grupos Focais que orientaram a elaboração de um questionário voltado para a identificação dos fatores de risco do sistema viário, comportamentos de risco e opiniões relacionados com os tipos de mensagens de campanhas. Este questionário foi posteriormente aplicado a uma amostra de condutores, juntamente com o DBQ &#8211; Driver Behaviour Questionnaire, este orientado para a identificação de comportamentos de risco de cada inquirido. A associação desses dois instrumentos permitiu a identificação de fatores de risco no sistema viário, assim como comportamentais de risco habituais e as preferências dos inquiridos sobre tipos e mensagens de campanhas, bem como meios de mídia. A análise estatística dos dados coletados permitiu identificar os seguintes fatores de risco relacionados à via: (1) más condições da infraestrutura da via, (2) más condições de sinalização, (3) más condições dos veículos que trafegam pelas vias, e (4) interação principalmente com pedestres. Foram ainda identificadas as suas opiniões relativamente a comportamentos-problema dos demais usuários do sistema viário, destacando-se os seguintes fatores: (1) sono, (2) bebidas, (3) drogas e (4) mensagens de texto. Quanto à importância das campanhas, os inquiridos consideram que elas devem: (1) ser dirigidas aos fatores de risco identificados, (2) estar associadas a outras ações como fiscalização e (3) seus resultados devem ser divulgados pelos órgãos de governo. Finalmente, acerca das mensagens das campanhas e tipos de mídia utilizados, os inquiridos consideraram que as mensagens devem: (1) utilizar laços afetivos, (2) ser mais impactantes, (3) conter cenas reais, (4) ter finalidade educativa; e as mídias mais adequadas seriam: (1) televisão, (2) internet (com ênfase às redes sociais) e (3) painéis de mensagens variáveis. Quanto ao questionário DBQ, foram identificados sete fatores comportamentais dos próprios inquiridos com maior peso e relação com atos inseguros: (1) Baixo nível de aptidão, (2) Infração, (3) Distração/Inatenção, (4) Condução agressiva, (5) Baixa consciência da situação, (6) Estresse e (7) Adaptação Comportamental. Esses fatores representam os tópicos prioritários que devem ser trabalhados em futuras campanhas. / This research established the methodological principles based on the identification of risk factors necessary for elaboration road safety campaigns, following the guidelines recommended by the CAST (Campaigns and Awareness-raising Strategies in Traffic Safety) project, which defines the identification of main problem behaviors generating accidents as an essential element in the definition of each campaign goal. Since there is no consistent and reliable statistical data proveding this information, it was necessary to identify the behavioral factors that originate unsafe acts and that should be priority in road safety campaigns. In order to achieve this result, it was necessary to establish a methodology involving the use of different data collection tools with the intention of identifying the problem behaviors, as well as other factors related to the infrastructure and environment capable to induce these behaviors. This methodology involved Focus Groups application that directed the elaboration of a questionnaire aiming at a identifing road system risk factors, risky behaviors and opinions regarding the types of campaigns messages. This questionnaire was further applied to a drivers\' sample, together with the DBQ Driver Behavior Questionnaire, which was directed to the identification of risky behaviors of each respondent. The association between these two instruments enabled the identification of road system risk factors, as well as common risky behaviors and the respondents\' preferences about the types of campaign messages and media means. The statistical analysis of the collected data enabled the identification of the following risk factors related to the road system: (1) poor road infrastructure conditions, (2) poor signing conditions, (3) poor vehicle conditions, and (4) interaction mainly with pedestrians. Opinions about problem-behaviors were also identified, stressing the following factors: (1) drowsiness, (2) drink and drive, (3) drugs and medication effects (4) texting driving. Concerning the campaigns importance, the respondents considered that they should: (1) be directed to identified risk factors, (2) be associated to other actions such as enforcement and (3) have its results published by the government entities. Finally, regarding the campaign messages and the used media types, the respondents considered that the messages should: (1) use affective anchors, (2) be more impactful, (3) contain real scenes, (4) have educative purpose; and the most adequate media would be: (1) television, (2) internet (with emphasis to the social networks) and (3) variable message panels. With respect to the DBQ questionnaire, seven behavioral factors based on the respondents own experience were identified as more important and related to unsafe attitudes: (1) poor fitness to drive, (2) violations, (3) distraction/inattention, (4) aggressive driving, (5) poor situation awareness, (6) stress and (7) behavioural adaptation. These factors represented the priority topics that should be handled in future campaigns.

Driverless cars are a hot topic in today’s industry where several vehicle manufacturers try to create a reliable system for automated driving. The advantages of highly automated vehicles are many, safer roads and a lower environmental impact are some of the arguments for this technology. However, the notion of highly automated cars give rise to a large number of human factor issues regarding the safety and reliability of the automated system as well as concern about the driver’s role in the system. The purpose of this study was to explore the effects of systematic variations in traffic complexity and external time pressure on decision-making time in a simulated situation using a web-based testing platform. A secondary focus was to examine whether measures of cognitive performance and driver attitudes have an effect on decision-making time.  The results show that systematic variations in both time pressure and traffic complexity have an effect on decision-making time. This indicates that drivers are able to adapt their decision-making to facilitate the requirements of a certain situation. The results also indicate that intelligence; speed of processing and driver attitudes has an effect on decision-making time.