This thesis begins with a brief overview of vehicle control. The thesis places powertrain control, which is discussed in more detail, within the wider context of vehicle control. Traction control is one aspect of powertrain control. The available methods of traction control are reviewed together with a discussion on the systems in current production. The traditional method adopted by the automotive industry for traction control is analysed. The powertrain system is analysed from a control stand-point and a control oriented approach to traction control design identified. The emphasis in this thesis is on the analysis of traction control systems. The analysis is performed on simulation models and is supported by implementations on the real vehicle. The level of modelling appropriate for the analysis is justified and models developed in a modular manner. The individual modules are developed on the basis of published material and previous work within Ford Motor Company. Based on the analysis, two traction control strategies are developed which are subsequently developed and implemented on real vehicles. The results of this vehicle work is discussed.

The theme of this thesis is concerned with the modelling of the multi-physics interactions that occur in lightning and arc discharge. The main contributions of this research are presented as combining different physical studies namely, electromagnetic (EM) propagation, thermal diffusion and non-linear materials using a numerical algorithm. The algorithm was developed based on the two dimensional (2D) numerical transmission line method (TLM). The algorithm was applied to several practical examples namely, to model the electro-thermal analysis and the temperature development in a plasmonic nano-heat sources for terahertz applications; to predict the shape and the location of an arc discharge channel caused by a lightning strike using electro-thermal analysis, and to model diverter strips for lightning protection on aeroplanes. Different electro-thermal coupling approaches, such as fully and partially coupled methods were used to investigate the efficiency and accuracy of the model. In the fully coupled method the thermal model was allowed to change the electrical properties of materials in the electromagnetic model. On the other hand partial coupling did not consider the temperature dependency of the electrical properties in the electromagnetics model. Both of the models used the dissipated power from the electromagnetic model as a source signal to evaluate the temperature profile in the thermal model. Also different coupling interval timesteps were investigated to minimize the computational power needed without affecting the model accuracy.

The aerospace industry is facing new challenges to meet burgeoning customer demand. An unprecedented number of orders for commercial aircraft has placed great urgency on aerospace manufacturers to make gains in production efficiency. Wing assembly is one such area where cycle times are in the order of hundreds of hours and commissioning cells can take several years which has led to a significant order backlog. In light of these challenges, new techniques are required to bring about greater agility to respond to market changes. Aerospace manufacturers must seize the opportunity to innovate and readdress approaches to ensure their prosperity. Recent research advocates Reconfigurable Assembly Systems (RAS) as a viable solution. A RAS is designed at the outset to change in structure to modify production capacity and functionality to meet new requirements. Yet, adding reconfigurability further increases design complexity. Despite the increased complexity, few formal methodologies exist to support RAS design for aerostructures. A novel RAS design methodology is presented to address the design complexity and the specific needs of Airbus. The methodology is a systems design approach consisting of reconfigurability principles, Axiomatic Design and Design Structure Matrices. Customer needs and existing knowledge are used to systematically specify scalable and customisable functionalities from the outset. These requirements and constraints are then translated into physical system designs modelled using CATIA, a 3D modelling software suite. The design methodology is applied in two case studies for wing assembly to produce full-scale factory designs. The designs are compared with current Airbus baselines in production ramp-up scenarios. The RAS demonstrate capability to change in structure for rapid increase in capacity at comparable cost to fixed systems. Greater capacity and shortened ramp-up time evidently reduces backlog compared to current systems. The first case study focused on technical development of a RAS and found potential ramp-up reduction of 88% and 10% less Capital Expenditure (CapEx) over 10 years. The second case study for a current wing scenario found reductions of 50% to ramp-up and 41% less tooling CapEx compared to a pulse line for a 12-year production cycle. The designs and scenarios were validated in formal Airbus design reviews. The case studies present the first instances of production-scale RAS for aerostructures. The RAS designs are made possible by designing from the outset using a novel design methodology which sets a precedent for the future of aerostructure assembly and opens up new possibilities for future research.

Emergencies are safety critical situations where decision-makers make rapid and quick decisions. It is essential that decision-makers maintain a high level of performance whilst resolving the incident. Knowledge of human factors influences on decision-maker performance is critical to understand when designing technologies to support naturalistic decision-making. Previous work has largely focused on the influence of a single human factor on naturalistic decision-making. However in naturalistic decision-making environments, such as resolving an emergency, often requires the interaction of multiple human factors with a resulting cumulative impact on the decision-making process outcome. This thesis presents a set of studies that investigates multiple, co-occurring human factors influences for naturalistic decision-making and investigates integration of the factors in the design of technologies to support effective outcomes in emergency situations. Findings contribute further understanding of the multi-factor influences on naturalistic decision-making, and provide a novel and practical set of design principles to support the design of naturalistic decision-making technologies. A literature review confirmed that a majority of research presents single factor influences on decision-making, which is out of step for real-world naturalistic decision-making. In addition, findings showed that multiple factor influences co-occur in naturalistic decision-making environments, and are associated with decision-making performance. Seven factors were identified; situation awareness, mental models, workload, human error, uncertainty, teamwork and communication. Two studies using real-world decision-makers from the aviation domain and _re and rescue domain, investigated the multi-factor issues and the association with decision-making performance, through a set of real-world incident case studies. Results demonstrate the occurrence of the seven factors, and the cumulative impact on decision-making performance. In collaboration with Airbus Defence and Space an experimental study with pilots contributed the design of a novel single pilot operated aircraft interface built using the understanding of the seven human factors. The interface was implemented in a flight simulator, where fourteen pilots performed three emergency related tasks. Results showed that the design had similar performance to that of a system based on the current design methodology, in spite of the fact the pilots had little experience with the system. Based on all findings, twenty-two cognition informed system design principles were created, with an aim to provide naturalistic decision-making system designers with a guide of how to integrate the seven factors into the design of systems to support effective decision-making. A final validation study, with human factors experts as participants, was carried out which identified the usability, validity and applicability of the design principles. The thesis contributes findings that have both theoretical and practical implications. This research has addressed gaps within the naturalistic decision-making literature and contributed new understanding to the complex field of naturalistic decision-making for emergency situations. Findings suggest that seven factors influence naturalistic decision-making, thus potentially affecting the decision-maker's performance. In addition, this research contributes an understanding of the guidance that is required by designers to create technology. Technology created using this methodology allows decision-makers to improve decision-making performance by supporting their complex decisions, thereby maintaining and improving safety in naturalistic decision-making domains.

In recent years there has been a growth in the automotive industry, coupled with a growth in the amount of electronic components and systems in a modern vehicle. The higher amount of electronics has led to an increased amount of Electronic Control Units (ECU) in a vehicle which require advanced simulation based testing procedures throughout their development process. One such method is Hardware in the Loop (HIL) simulation in which a real ECU is connected to simulation models of its environment via a real-time simulator. This project is concerned with developing a plant model of a windscreen wiper system for use in the development of Jaguar Land Rover’s (JLR) body electronics ECU. The system is divided into four parts which are modelled separately: Wiper motor, linkages, arm and blades, and the windscreen environment. The wiper motor and mechanical elements models are derived and implemented using the physical modelling tools SimScape and SimMechanics. A dynamic friction model describing the interaction between the wiper blades and the windscreen is developed, based on results presented in the literature. A simple aerodynamic model describing the forces on the wiper blades is also established. The parameters of the models are derived using three sequential optimisation methods: Transfer function parameter identification, Genetic Algorithms (GA) and a nonlinear least squares local optimiser. A transfer function relating the motor current to the voltage was derived for step one, and a bespoke GA has been developed for step two. The parameters were successfully identified. Following this, Artificial Neural Networks (ANN) were used to convert the physical models into real-time capable models suitable for HIL simulation. Finally, adaptive control systems are designed in order to maintain the motor at a constant velocity. The models are presented in a Simulink library and graphical user interface modelling tool for ease of use.

Detailed analysis of the flow around a NACA0020 aerofoil at moderate low chord Reynolds number (Rec = 2×104) in completely stalled conditions has been carried out by means of Direct Numerical Simulations. The stalled condition is either a steady configuration at a fixed angle of attack (α = 20o) or it is reached via a ramp-up manoeuvre, increasing the angle of attack from 0o to 20o. Concerning this last case, new insights on the vorticity dynamics leading to the lift overshoot, lift crisis and the damped oscillatory cycle that gradually matches the steady condition, are discussed using a number of post-processing techniques. These include a detailed analysis of the flow ensemble average statistics and coherent structures identification that has been carried out using the Q-criterion and the Finite-Time Lyapunov Exponent technique. Based on the fundamental knowledge achieved in studying the static and the dynamic stall, we introduced a biomimetic passive control technique to mitigate the aerodynamic performance degradation typical of such flow conditions. In particular, the envisaged control technique has been inspired by the dorsal feathers that are used by almost all birds to adapt their wing characteristics to delay stall or to moderate its adverse effects (e.g., during landing or sudden increase in angle of attack due to gusts). Some of the feathers are believed to pop up as a consequence of flow separation and to interact with the flow producing beneficial modifications of the unsteady vorticity field. The adoption of self adaptive flaplets in aircrafts, inspired by birds feathers, requires the understanding of the physical mechanisms leading to their aerodynamic benefits and the determination of the characteristics of optimal flaps including their size, positioning and ideal fabrication material. In this framework, we have used numerical simulation to study the effects of this passive control technique in both steady and dynamic stall. In particular, for the static case, we have defined an optimal condition as the one that delivers the highest lift coefficient CL, preserving or improving the aerodynamic efficiency E = CL/CD. To achieve a condition close to optimality we started by considering a simplified scenario, to determine the main characteristics of the flap (i.e., variations of its length, position and natural frequency). Later on, a detailed direct numerical simulation analysis is used to understand the origin of the aerodynamic benefits introduced by the pop-up of the optimal flaplet. It is found that an optimal flap can deliver a mean lift increase of about 20% on a NACA0020 aerofoil at an incidence of 20o degrees. The analysis of direct numerical simulation data of the flow field around the aerofoil equipped with the optimal flap allowed to elucidate the main mechanism that promotes the aerodynamic improvements. In particular, it is found that the flaplet movement, induced by the transit of a large recirculation bubble on the aerofoil suction side, displaces the trailing edge vortices further downstream, away from the wing. The downstream displacement of the trailing edge generated vortices, limits the downforce generated by those vortices also regularising the shedding cycle that appears to be much more organised when the flaplet is activated. A similar study has also been carried out for the dynamic case. We have analysed the effects produced by the presence of an elastically mounted flap on the transient behaviour of the flow fields. For a specific ramp-up manoeuvre characterised by a reduced frequency slower the shedding one, it is found that it is possible to design flaps that limit the severity of the dynamic stall breakdown. In particular, it is possible to increase the value of the lift overshoot and to smooth its abrupt decay in time. A detailed analysis on the modification of the unsteady vorticity field due to the flap-flow interaction during the ramp-up motion is also provided to explain the physical mechanism that lead to more benign aerodynamic response.

This thesis contains a formal mathematical investigation of clutch engagement in automotive vehicles. This investigation is conducted by developing a model of an automotive powertrain, and investigating undesirable effects that can occur in clutch engagement. This naturally leads to the development of a multi-objective optimal control problem describing how to best to engage a clutch. An algorithm for solving this optimal control problem is then presented. Arguments for the development of a feedback control strategy are then discussed, with the construction of such a feedback strategy, along with the computations required to evaluate the feedback controls detailed. A further extension, of adapting the feedback controls, to cope with powertrain model perturbations then follows, along with a method of estimating such perturbations. Finally, the use of this research in implementing clutch engagement control is outlined. Throughout the thesis, the various control strategies designed are evaluated by carry out simulations of models representing the powertrains of two different family cars.

The substantial increase in powerful electronic systems and functions has produced significant implications for the vehicular industry, where the amount of wiring infrastructure has increased the vehicle weight, weakened performance, and made adherence to reliability standards difficult. Eventually, connecting the electronics infrastructure was mostly complicated and costly in vehicular domain systems. Thus, little research has been conducted to explore appropriate wireless technologies that may be suitable with the emerging network standard within the context of vehicular networks. This thesis describes an in-depth investigation of deploying an optical wireless communication system within the vehicular environment, particularly in confined spaces. A wide variety of measurements has been performed using tubes of various materials and geometries, in a laboratory setup. The principle objective is to provide a primary knowledge of optical wireless channel characterization within a laboratory vehicular setting. The work presented is a study on directed line-of-sight (LOS) and non-LOS (NLOS) links, and focuses on frequency response, power efficiencies, and path losses in different experimental settings. Further, a variety of experimental settings was used in respect to different receiver/transmitter orientations and various bent tubes angles in order to investigate the channel conditions. The noise analysis, xviii SNR, path loss and the eye pattern for the digital system prototype designed were also analysed. The system requirement for the LOS link were based on the transmission of the sinusoidal signal at a distance of 1 m with 13 MHz signal and approximately 15.6 dB SNR. Successful demonstration of the OWC within smaller size and high reflection coefficient material are promising. In addition to good transmitter and high sensitivity receiver. The NLOS link also demonstrated a good indication, both in straight tube with angled transmitter/receiver orientation and bend tubes. Detail studies on NLOS link with pulse signal transmission, which replicates a digital system transmission with 54.48mW or 44.58 mW/cm2 output power,6 MHz signal transmission with the aim of 10-4 to 10-6 BER. Although, the operational functionality of digital system has successfully demonstrated, however achieving the desired BER is a bit difficult with the designed system. Further improvement on the highly sensitive receiver design, a proper modulation scheme is required in order to improve the quality of the transmitted signal in terms of SNR and BER. The study also suggested that the transmission within the metal tubes is better than in plastic tubes in addition to minimum bend angle, smaller tube diameter and high reflective coefficient. Transmission within 20 mm circular aluminium tube and 35 mm galvanised aluminium tube are the best so far. Finally, based on the initial viability results, it was seen that it is possible to implement an optical wireless communication infrastructure within the vehicular environment. Experimental validation of the system proposed shows that achieving high data rates is not a problem with the use of high brightness, high power LEDs as this system is xix going to be implemented within the vehicle chassis, thus the eye safety constraints should not be a limiting factor. Therefore, in this study, optical wireless transmission within the vehicular environment is proposed, solving the problems of vehicular networking systems.

This thesis investigates the application of the concepts of fairness and equity in Air Traffic Management (ATM), specifically focusing on trajectory-based operations. One of the main objectives of these new type of operations, which are at the core of the two major ongoing ATM modernisation initiatives (SESAR in Europe and NextGen in the United States), is to enable Air Navigation Service Providers (ANSPs) to better accommodate the trajectories preferred by the different airspace users. In this context, it is pivotal to ensure that all airspace users are dealt with impartially by the ANSP responsible for monitoring, adjusting and clearing their trajectories. Thus, fairness and equity considerations need to be integrated in the definition and implementation of trajectory-based operations. In view of the lack of a rigorous approach to the integration of the concepts of fairness and equity in trajectory-based operations, this thesis proposes fairness and equity metrics to assess the impact of the decisions of ANSPs on the distribution of cost penalties among different users. In this context, a cost penalty is defined as the increment in operational cost for the user that results from being cleared to fly a trajectory that is different from its preferred one. In addition, this thesis proposes methods to incorporate the aforementioned metrics to the decision-making process of ANSPs in the context of trajectory-base operations, so that the trajectories assigned to the users may be fair to all of them. In a first step, this dissertation derives specifically for ATM the concepts of justice, fairness and equity from traditional disciplines such as Philosophy, Economics or Sociology. These theoretical notions are the foundations for developing the mathematical expressions to obtain quantitative values of fairness and equity in the context of future trajectory-based operations. These fairness and equity metrics are initially defined considering that each flight is an independent airspace user and later generalised to the possibility of airspace users simultaneously operating several flights in the same operational context, e.g. a scenario including several airlines where each one is operating several flights. Secondly, the practical application and incorporation of the developed metrics into the existing ATM systems is explored. Two different methodologies to apply the proposed fairness and equity metrics in practice are presented, each one addressing a specific example where using such metrics could benefit future trajectory-based operations. Specifically, the proposed methodologies deal with how to incorporate fairness and equity considerations in the design and evaluation of so-called trajectory management algorithms, which will be used by future ATM systems to adjust the airspace users’ preferred trajectories so that they remain conflict-free within a given time frame, e.g. during the arrival phase. The usability of the metrics according to the proposed methodologies is illustrated by means of specific and ATM-relevant examples. On the one hand, the integration of the fairness metric into a trajectory conflict resolution algorithm is presented with a view to enlarge the optimisation criteria of trajectory modifications, i.e. inclusion of fairness considerations during trajectory adjustments. On the other, a comparative assessment is described with regard to fairness and equity of three different conflict resolution algorithms for a given environment, i.e. operational context, route network and traffic situation. To complement the above, a preliminary robustness analysis of the proposed fairness and equity metrics has been conducted. This analysis is an important part of this work, addressing explicitly the need of particular characteristics in the ATM environment for successfully making use of fairness and equity metrics, identifying situations that can affect the effective application of metrics and establishing the provisions to guarantee it. This study is based on concepts from the field of Decision Theory where the ATM system is modelled to reflect the de-confliction of trajectories based on user preferences in a two-player game with a fairness-oriented ANSP. In summary, this thesis proposes a new framework to incorporate fairness and equity in future air traffic operations based on quantitative metrics. The framework includes methodologies to apply these metrics in practice with a view to enabling the fair or equitable distribution of cost penalties among users in trajectory-based operations.

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