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Britain has some of the lowest road crash casualties globally (by head of population), yet tens of thousands of people are affected each year, and numbers have plateaued. Despite the impact of road trauma, there has been limited evaluation of Britain's policy response. This research is the first to use Kingdon's (1995) multiple streams analysis to evaluate agenda setting, analyse how policies were made or not made, and considers framing, the impact of political and organisational factors, and future policy. Critical discourse analysis evaluates primary data acquired via thirty-five interviews with policy participants, as well as secondary data from Parliamentary debates, and policy documents between 1987 and 2021. Three case studies on macro policy making, rural roads and young drivers are analysed. Two different time periods were identified: prior to 2002, the policy problem was accepted, policy solutions advanced, the policy window opened as political discourse was constructive, the policy streams coupled, and policy change resulted. After about 2003 the policy problem was not accepted as road deaths were framed as accidental and so unavoidable, solutions were contested, the politics stream flowed slowly, and from 2011, the tight fiscal environment, discarded targets, the shift towards localism and significant competition for attention, policy stability resulted. Competing policy images suggested complacency due to inaction, or Britain's position was framed as one of the best in the world. Political and organisational factors impacted on whether there was policy change or stability. The key barrier was the politics stream, where the lack of visible public support, and indifference from the media resulted in limited attention and action from politicians. In conclusion, until the road safety community unites in engaging in how road safety can successfully compete with other policy areas, it is unlikely to persuade politicians it is worth the political capital of introducing unpopular or controversial changes, even if they save lives.

Inconsistencies can be observed in the way vehicles equipped with driving automation features will inform drivers about a particular system's state or capabilities and limitations: different graphical symbols are used across manufacturers to represent the same feature, while other graphical elements presented on the instrument panel can also differ in their designs. This situation could engender confusion among drivers, while some designs may be less informative and/or less usable than others, eventually being detrimental to driver safety. The objective throughout this project, therefore, was to demonstrate whether symbol confusion was an actual risk and whether the different symbol and interface designs could have measurable consequences on a vehicle's usability. Ultimately, the goal was to determine which methodological approach could help design symbols and interface elements that would prevent or mitigate these putative consequences. Firstly, two studies were conducted with a user-centred design (UCD) and participatory design approach to ① investigate drivers' mental models of the adaptive cruise control (ACC) and lane centring control (LCC) systems and design symbols for these two systems, and then, to ② research which symbols would be the most recognised by drivers contextually and alongside other symbols present in vehicles. Secondly, two driving simulator studies were conducted to ③ compare the usability of different graphical elements shown on the instrument panel for ACC, including different designs of the same symbol, and finally, ④ compare two sets of symbols for ACC, LCC, lane departure prevention (LDP), and the automated lane-keeping system (ALKS), in terms of driver preference, but also on how much confusion and how many errors would occur while drivers were using either set. Overall, the results suggest that some existing symbols (notably the standard ones) lack information about which actions are automated by a system, or how the visual representation of the environment relates to the actions performed by the system. In scientific jargon, drivers overall preferred, recognised, and committed fewer errors with symbols that depicted drivers' affordances and the signifiers that the vehicle was using in place of the driver. Through this project, it was observed that: indeed, symbols can confuse drivers and contribute to use errors of the automated driving features; that interface designs could impact the usability of vehicles differently; and finally, that a combination of UCD and participatory design can help design better symbols. In the case of symbols for driving automation systems, designers should consider the context of use of the system and which affordances/signifiers should be represented on the symbol.

Interacting with pedestrians remains challenging for autonomous vehicles (AVs). In most current AVs, for safety and legal reasons, pedestrians are considered as obstacles, such that the AVs always stop for them. But their highly safe nature may lead pedestrians to take advantage over them and slow their progress. When a pedestrian wishes to cross the road in front of the vehicle at an unmarked crossing, the pedestrian and AV must compete for the space, which may be considered as a game-theoretic interaction in which one agent must yield to the other. Game theoretic approaches have been used for decades to model the interactions between rational decision-makers, but have run in parallel streams with psychology research on human proxemics and trust. Results from game theory and psychology studies have yet to be operationalised for autonomous vehicles, this thesis thus aims to bridge the gap between these separate fields. We first contribute with a comprehensive review of the literature in which we propose a new unifying taxonomy of pedestrian models required for autonomous driving, linking the low-level and high-level models of behaviour for the first time. We find that the low-level models are mature enough to be deployed in the real world but the high-level models such as game theory approaches still require more research and development. We therefore proceed with the evaluation of pedestrian interaction preferences with a game theoretic AV in a virtual reality experiment. Knowledge of such preferences could then be used by future AVs to predict and control for pedestrian behaviour. However, game theory approaches require the use of credible threats such as crash probabilities in order to make AVs progress on the roads, but another possible and more friendly solution that is explored in this work is Hall's theory of proxemics. Hence we propose a novel Bayesian method to infer pedestrian proxemic utility functions and the concept of physical trust requirement (PTR) for game theoretic AV interactions. We show how this PTR model can accurately generate Hall's empirical zone sizes, and then extend it to more general human-human and human-robot interactions. Finally, operating and deploying pedestrian behaviour models require the use of a physical AV platform, we hence introduce OpenPodcar, a low-cost, open source hardware and software platform developed for real-world AV research experiments with pedestrians. Thus, the present thesis forms a step towards the first operational game theoretic autonomous vehicles with pedestrian proxemic and trust behaviour.

Using data from the large-scale European Naturalistic Driving project (UDRIVE), this thesis explored the prevalence of engagement in secondary tasks whilst driving through intersections and investigated whether drivers self-regulate such behaviour in response to variations in roadway and environmental conditions. The thesis also examined the possible influence of secondary task engagement on turn signal usage at intersections. To these ends, 1630 intersection cases were randomly sampled from the UDRIVE dataset for coding and in-depth analysis. In-vehicle video recordings and recordings of external scenes in the selected sample were coded for precisely defined categories of secondary tasks and related contextual variables. The findings indicated that nearly one-quarter of the total driving time at intersections was spent on secondary activities and that such engagement decreased with increasing age. The drivers were less likely to occupy themselves with secondary tasks as they passed through an intersection itself, as opposed to the approach (upstream) and exit (downstream) phases. The drivers also tended to perform secondary tasks less frequently when their vehicles were moving than whilst they were stationary, when they did not have priority to pass through intersections compared with when they had priority and in bad weather conditions than in fine weather situations. Lastly, the drivers showed less inclination to use turn signals when they were engaged in secondary tasks than when they were driving under normal baseline conditions. In conclusion, the drivers appeared to self-regulate secondary task engagement according to road and driving situations, specifically when the primary task of driving becomes progressively challenging. This self-regulation behaviour was particularly strong for more complex and, therefore, more demanding secondary activities. The outcomes provide initial evidence that can serve as reference in targeting countermeasures and policies related to safe driving and managing distractions.

Fatigue can result in cognitive impairment and reduced vigilance, and driver fatigue is believed to be a significant contributing factor to road traffic collisions. In addition, fatigue-related road traffic collisions are more likely to result in fatalities. Identification of fatigue-related collisions is not easy; however, these types of incidents more often occur in the very early hours of the morning, or to a lesser degree, in the early afternoon. This is due to the circadian rhythm, influencing the natural sleep and wake periods of humans. Due to the time of day that these incidents are more likely occur, those who work irregular hours, or shift work, are potentially more at risk of driving whilst fatigued, and therefore being involved in a fatigue-related incident. Police officers and civilian police staff are one group who work irregular hours or rotating shifts and are therefore potentially more vulnerable to driver fatigue. The extent to which driver fatigue is an issue amongst this group has not previously been explored in this manner, in the UK. In addition, sleep duration whilst working shifts, and cognitive performance has not previously been tested with this group. This thesis describes two studies conducted with serving police officers and civilian staff. A questionnaire study was utilised in order to explore the experiences of those working in the policing organisation, in relation to commuting habits and road traffic incidents. This was then followed up with an empirical study that investigated a particular shift pattern, common in UK policing, in an attempt to identify sleep duration, and differences in cognitive performance and vigilance during the different shifts worked. Questionnaire responses identified that the particular group of participants in the first study reported a high prevalence of driver fatigue whilst travelling to and from work, which often resulted in road traffic incidents. The second study revealed that sleep duration following night shifts was significantly reduced. In addition, overall, the results indicated that participants coped well with the particular shift pattern studied. This research makes a valuable contribution to the literature around shift work and driver fatigue in UK policing. It provides potential for learning in respect of favourable shift patterns, and opportunities for training and change, where it is imperative in relation to staff wellbeing. Future research needs to consider the influence of alternative shift patterns on fatigue and related road traffic incidents, using a larger number of participants, in differing policing areas. This approach would also be beneficial for other emergency services and large shift working organisations, to reduce the number of fatigue-related driving incidents in all shift-workers.

Aviation authorities suggest that commuting to the airport can impair pilots' flying performance by inducing fatigue. That risk might be particularly high after long drives of high task load because they deplete individuals' attentional resources. Flying may then increase commuting pilots' levels of fatigue further leading to performance decrements while driving after duty. This thesis explored the extent of this issue among professional pilots worldwide and investigated if the type of fatigue induced by driving (i.e. active or passive) subsequently affects the levels of fatigue experienced in flying and driving. The effectiveness of a self-initiated intervention strategy for fatigue experienced in the commuting cycle after a long and demanding drive was explored too. The extent of the issue was investigated with an online survey of 419 professional pilots flying from 52 countries. The pilots were asked about the usual duration and levels of mental demand of their drives to the airport and their usual levels of fatigue during the commuting cycle. Moreover, they answered questions about their difficulty in staying awake and performance in flight and while driving after duty. The survey suggested that many professional pilots worldwide are at an increased risk of fatigue-related aeroplane accidents and car crashes after duty when driving to the airport is long and mentally demanding. Therefore, the role of active fatigue was indicated. Exploring the role of the type of fatigue induced by driving in fatigue experienced in subsequent flying and driving is essential in order to develop effective intervention strategies. This considered, an experiment with 60 non-pilots was conducted. Three groups (i.e. control, manual, and automated) completed for 32 minutes simulated flying tasks that did not require having pilot training. These tasks were followed by a 14-minute, simulated drive (level 0 of automation). The manual and the automated group also completed a 60-minute simulated drive (level 0 of automation for the manual and level 2 for the automated group) before the flying tasks. This study suggested that completing a long drive can increase individuals' levels of fatigue in flying and driving tasks that follow, especially when that long drive induces active fatigue. Active fatigue can reduce with short bursts of physical activity. Hence, the second experiment investigated if such breaks can help individuals to counteract fatigue in flying and driving tasks that are completed after a long and demanding drive. Fifteen individuals with a Private Pilot's Licence completed a 60-minute simulated drive (level 0 of automation) followed by a 52-minute simulated flight of higher fidelity compared to the first experiment and a 20-minute, simulated drive (level 0 of automation). In one of their two sessions, the participants took two 6-minute breaks; one before and one after the flying tasks. It was found that the participants were less fatigued and performed better in flight and during the short drive when they took the breaks. Hence, short bursts of physical activity could be one of the intervention strategies that pilots could use to reduce their levels of fatigue after long and demanding drives to the airport. The outcomes of this thesis could be used by regulators, airlines, pilots, and researchers to work towards understanding in more depth fatigue in pilots who commute to the airport by completing long and demanding drives. Then, appropriate self-initiated intervention strategies, training, policies, work schedules, and fatigue regulations could be developed.

The overall aim of this thesis was to study the effects of a simulator's motion system on vestibular motion cueing fidelity in different contexts, evaluated in terms of drivers' perception and behaviour, in low and high road friction conditions. The effects of manipulating the motion cueing algorithm (MCA), was found to be a function of the vehicle motion in a manoeuvre, and significant effects were observed. The applicability of simulators for the assessment of vehicle driven attribute qualities such as ride, steering and handling were studied by manipulating vehicle ride height (RH). The differences between the RHs were subjectively distinguishable by the drivers in the simulator. Incongruities between the subjective preferences and objective performances were observed in both of the independent comparisons of the MCAs and RHs. The effects of motion platform (MP) workspace size were found to be dependent on the manoeuvres and road friction level. In the low-friction condition, with the increase of MP size, two opposite effects were observed on drivers' preferences and their performances, depending on the manoeuvre. In high-friction, in most of the handling and steering qualities, a direct relation was found between the MP size and appropriate vehicle RH. Furthermore, the optimal tuning of the MCAs and optimisation of the MP workspace size was introduced. A conservative motion cueing fidelity criteria was defined. A multi-layered optimisation method was developed that uses the optimal setting of the MCA, to address the MP translational workspace size, and to meet the fidelity criteria; applicable for different manoeuvres. This method was tested on the drivers' performance data collected from the experiments in the simulator.

Unsafe driver behaviour is regarded as the most significant contributory factor in road traffic crashes in Nigeria, and the prevailing road safety culture in the country is one aspect which sustains the high crash rate. This research used a problem-oriented approach with the intention to recommend research-based solutions to road safety problems in Nigeria while considering cultural and environmental factors that provoke different driving styles and behaviours. It aims to identify which, among culture and road environment, has a stronger influence on drivers' behaviour and how behavioural changes can be achieved. To achieve this, a multi-method approach was adopted in different phases. Phase 1, an exploratory study involved on-road observation of traffic behaviour and conflicts in Nigeria using the Traffic Conflict Technique (TCT). It provided an understanding of the general traffic behaviour of various road users, showed the effect of various factors on conflict severity and helped to identify the most prevalent unsafe behaviours found in this environment. Based on the results of this study, a driving simulator experiment was designed and carried out in Phase 2, comparing the driving style of three groups of drivers in varying road conditions. These were Nigerians with no experience of driving in the United Kingdom (UK), Nigerians with some experience of driving in the UK and UK drivers. The conditions varied depending on how much regulation was provided (low or high infrastructure). A short road safety awareness-raising intervention for Nigerian drivers with no experience of driving in the UK was also evaluated. It was hypothesised that those Nigerian drivers with no experience of driving in a highly regulated UK road system would not be encouraged to adopt a safe driving style. This would have implications for the use of road safety interventions in Nigeria that have been developed outside the Nigerian context. In addition, participants completed the Driving Behaviour Questionnaire (DBQ) to compare reported behaviour and objectively measured driving behaviour in various traffic scenarios (overtaking, lane changing, car following etc.). Since many road safety measures could not evaluated for Nigerian drivers in phase 2, a focus group study was conducted in Phase 3 with the lead road safety agency in Nigeria-the Federal Road Safety Corps (FRSC). The study investigated the perceived effectiveness and ease of implementation of a wide range of road safety measures on drivers' behaviour including those that were evaluated in Phase 2 (simple engineering measures and awareness-raising campaigns). Results provided a greater understanding of the road safety situation in Nigeria. Some of the unsafe behaviours identified in Phase 1 are distinct and can only be found in a particular cultural environment like Nigeria because of the traffic conditions and vehicle fleet. Investigating some of these behaviours in Phase 2 and comparing them with the behaviour of drivers from other cultures showed that there were distinct differences in behaviour between all the groups in most of the traffic scenarios. Nigerian drivers with no experience of driving in the UK were more likely to engage in unsafe driving behaviours compared to other groups. Improvements in the road environment did not bring about any significant changes in the behaviour of this group of drivers. However, small changes were observed after the awareness-raising intervention. The results indicate that the behaviour of drivers are interpretable in relation to their traffic safety culture, and are only partly influenced by their driving environment. Specifically, drivers' traffic safety culture has a greater influence on their behaviour compared to changes in the road environment. Findings from the focus group study in phase 3 revealed that road safety measures such as education and information campaigns are perceived to have the potential to be very effective and easy to implement in Nigeria compared to other measures. The research findings provide an innovative approach to defining the key safety-critical behaviours which are prevalent in Nigeria as well as starting to understand how features of the road environment and/or training could be used to improve the road safety record in Nigeria. It also has implications for the design of road safety interventions in developing countries, particularly with respect to the non-portability of infrastructure measures from developing countries.

Emotions and moods are an inevitable part of human life. Previous research suggests that positive and negative moods affect human performance in many aspects: decision making, perception, reasoning and memory. The influence of mood on drivers’ behaviour has been studied to a less extent and mainly with respect to negative emotions. The studies reported in this thesis are based on psychological theories regarding the differences in the effects of positive and negative moods on information processing and mind wandering. The thesis describes two studies: a desktop study and a driving simulator study, which measure drivers’ responses to the actions of other traffic, their observational patterns and driving behaviours in a variety of scenarios. The effects of neutral, happy, sad and angry moods were studied. The simulator study also investigated possible ways to disconnect drivers’ minds from mood induced mind wandering by using different types of cognitive load. The results suggest that mood valence and arousal have different effects on driving safety, with negative moods resulting in the most dangerous driving. In order to draw conclusions about the effect of mood, a combination of multiple measures (e.g. glance patterns, driving performance and drivers’ physiological measures) should be analysed. The results also suggest that some amount of cognitive load, applied while driving, can have a positive effect on drivers’ attention. Further research is needed to establish the amount and type of the cognitive load necessary to improve drivers’ ability to maintain their attention on the driving task. Studies with a larger number of participants and field studies are needed to validate the findings. It is suggested that the findings are used to improve in-car assistance systems able to both detect the harmful effects of a driver’s emotional state and re-direct their attention to the primary task of driving.

Limited research has been applied to testing intervention effects on travel behaviour of attendees at major sport events. As travel to sport events accounts for a large percentage of carbon emissions there is a need to alter travel behaviour. The underlying premise is that it may be possible to influence intentions and promote change using marketing interventions mapped to the Transtheoretical Model of Change (TTM). A quasi experimental design was adopted using a case study approach in the execution of the experiment. 4 studies were employed in this research. Study 1 articulated how the TTM was incorporated into the design of the social marketing interventions. Participants (N = 14) helped to identify the most influential marketing interventions. Using an adapted questionnaire based on the Theory of Planned Behaviour (TPB), it was concluded that sports fans were not intending to change and their use of the car was supported by peers. In determining the relationship between TPB scores and level of influence of each marketing intervention, the indication was that Subjective Norm (SN) had a mediating impact. In study 2, participants (n =192) were categorised into Stages of Change (SoC) using an adapted TTM questionnaire. The remaining TTM constructs were also assessed. In study 3, a post-intervention questionnaire was distributed to a Control (N=22) and Experimental group (N = 20). The collective results revealed that the interventions did not work. Participants did not recognise travel by car as a problem behaviour despite an awareness of the environmental and health implications. Contextual determinants dominated decisions. It was challenging to determine the theorised relationship between SoC and other TTM constructs as the majority of participants were categorised as Precontemplators or Contemplators. Findings indicated difficulty in aligning Process of Change (PoC) items with the SoC characteristics in this context. Yet the relationships between SoC and decisional balance and self-efficacy suggested alignment to the prescribed theory. In study 4 interviewees evaluated the interventions and gave their reaction. In spite of a sense of engagement, there was no change in travel behaviour. The car was seen as the solution to a problem – getting to the match on time. The findings formed the basis of recommendations which furthered the application of the TTM and its applicability within a specific leisure context.

Obstructive Sleep Apnoea Syndrome (OSAS) is the most common form of sleep disordered breathing characterised by snoring, apnoeic episodes, sleep fragmentation at night and excessive daytime sleepiness. Some patients with OSAS are at increased risk of being involved in road traffic accidents (RTA). Compared to other individuals, some OSAS patients are at 2-6 times at risk of having a RTA. Clinicians are not only involved in screening, diagnosing, managing patients with OSAS but are often asked to make recommendations about fitness to drive and this is likely to be inconsistent in the absence of objective criteria. Some clinicians advise against driving in high-risk patients and in certain situations inform the licensing authorities. Driving simulators have been used in the research setting to predict fitness to drive in various situations. Many studies have used simple simulators that were unrealistic. The Institute for Transport Studies at the University of Leeds has developed a sophisticated driving simulator (UoLDS). Alongside this, a PC-based simulator (Mini University of Leeds Driving Simulator, MUoLDS) has been developed using the same software. Using continuously measured variables it has been possible to identify, with a high degree of accuracy, a subset of patients with OSAS who fail a simulated driving test. This has the potential to identify at-risk drivers and improve the reliability of a clinician’s decision-making. Before the MUoLDS can become useful as a clinical tool there are a number of further questions to be answered and the thesis will address some of these.

Eco-driving has the potential to reduce fuel consumption and therefore emissions considerably. Previous research suggests that drivers already possess a certain level of eco-driving capability, which they do not practise in their everyday lives. The studies reported in this thesis are based on a mental models approach, which enabled an in-depth exploration of eco-driving knowledge and skills and broadened the understanding of the underlying cognitive mechanisms. This thesis describes two driving simulator experiments aiming to measure, activate and ultimately interrupt eco-driving mental models in a variety of scenarios, relevant for safe and eco-driving. The studies used simple driving task instructions, text message interventions as well as a workload task. Changes in the participants’ behaviour and thoughts were analysed with a combination of quantitative and qualitative methods. The results suggest that drivers have mental models of eco-driving on several levels, ranging from knowledge and strategies to tactics in specific situations to automated behaviour. However, in the first experiment they did not use them when they were instructed to ‘Drive normally’. In the second study text message primes and advice provided over two weeks were not able to replicate the effect of experimental instructions given directly before driving. Behavioural changes following these instructions were abandoned when performing a workload task, and not resumed afterwards. Future research needs to consider alternative methods to prompt drivers to use their existing eco-driving knowledge and skills. Studies with a larger number of participants, and in real-world settings can then validate findings. It is suggested to expand the mental models approach into other fields such as sustainable transport in general.