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With the increasing development of Additive Manufacturing technologies in the past two decades, the area of lattice structures has received considerable attention due to their inherent advantages in providing lightweight, high stiffness, and strong materials. However, this comes with new challenges such as geometry modelling, optimal selection of unit cell for certain loading condition, and mechanical performance for practical applications. This research provides a systematic investigation of lattice structures from design, testing, to numerical investigation and analytical study, as well as a case study for practical engineering application. A new method to create lattice structures using the traditional CAD package was proposed. It can automatically generate parametric models of complex lattice structures. Three lattice structures with triangular unit cells, cubic unit cells and hexagonal unit cells are shaped by side length, L, strut thickness, t, and height, h (or layer number, n, in h direction). The prototypes manufactured from Nylon and AlSi10Mg show good manufacturability. The experimental tensile curves of the lattice structures reveal distinguished results from the traditional solid materials. The triangular lattice structure was found to be the best in terms of greater effective Young’s modulus (E*) and stiffness-to-mass ratio. The theoretical solution of E*for triangular lattice structure (E*EB) was derived based on Euler-Bernoulli beam theory. The numerical results of E*by using a representative volume element were obtained by Finite Element Analysis (FEA). The effects of L, t and h, on values of E* were investigated independently. The results show that t had the most significant effect. Values of E* obtained by the proposed analytical solution have shown the best agreement with the corresponding FEA results when compared with other existing methods. The experimentally determined values of E* are in excellent agreement with both analytical and numerical solutions. A new single part vehicle suspension with lattice structure was created using Creo®. As the lattice structure suspension is made of scale unit cells shaped by several parameters, it is time-consuming to run simulation with this model. Instead, solid suspension with E* of triangular lattice structure determined by the proposed analytical solution was used in FEA. The optimization method by Design of Experiments (DOE) was used to develop the formulae among design variables (L, t, h and T) and maximum von Mises stress, maximum deformation, stiffness-to-mass ratio and total mass. This method has proven to be an effective way to obtain the mechanical response of large scale lattice structures. The optimum parameters [T, t, L, n] are [2.90, 1.90, 7.82, 1] for the objective of maximum stiffness-to-mass ratio, which is found to be a conservative design. For the objective of minimum total mass, the optimized values are [0.55, 0.76, 4.88, 1], where the design can make full use of structure materials. In the future, these two different lightweight methods should be considered along with other requirements, such as vibration performance and failure behaviour.

As the energy and environment crisis increase severely, developing cleaner and more fuel efficient vehicles have become a research hot spot of automobile industry. In recent years HEV (hybrid electric vehicle) and EV (electric vehicle) are widely considered as two of the most viable solutions to the world’s need for cleaner and more fuel-efficient vehicles. This project aims to further improve the performance and fuel efficiency of EVs/HEVs for real application of urban driving. The thesis can be divided in to two major studies: EMB (Electro-Mechanical Brake) system development and HEV power management, which are two hot topics in the latest researches of EVs/HEVs. The brake system plays an important role in vehicles. As the X-by-wire technology develops, EMB can realize individual control of braking force on each wheel; which makes it very suitable for electrified vehicles. In this thesis a compact design of EMB actuator is proposed. To investigate the control of EMB system, a down scaled EMB test rig has been set up and an EMB motor control system has been developed. In the section of clamping force control of EMB system, in order to achieve fully control of braking force, a low cost sensor less clamping force control method is proposed. It is noted that in real applications of EVs/HEVs the EMB system is normally cooperated with regenerative braking system during braking process, in this thesis the co-operative control of hybrid brake system is investigated as well to improve the braking performance and regenerative braking efficiency. In order to overcome the drawbacks of the conventional gasoline vehicles, HEVs encompass two power sources (internal combustion engine and electric motor) to drive the vehicle. Due to existence of the double power sources, HEVs normally have multiple operation modes. The objective of HEV power management is to find the optimal power distribution on each power source to meet the power requirement with minimum fuel consumption. In this thesis to improve the fuel efficiency and keep the balance of battery SOC (state of charge) simultaneously during urban driving, a revised dynamic programming (DP)-optimized HEV power management control strategy is proposed. The DP algorithm is applied to obtain the optimal engine/motor power distribution and utilized for the design of the fuzzy control strategy. The traditional DP algorithm is modified with the consideration of SOC balance for HEVs. In the analysis of DP simulation results, rules of torque slip behaviors have been found, which are directly utilized in the design of fuzzy control strategy. In order to improve the practicality of the control strategy to meet the diversities of city driving patterns, an urban driving pattern recognition method is presented. To evaluate the control performance, the proposed control strategy is also compared with the conventional rule-based strategy. The simulation results indicate that by adopting the proposed strategy the fuel efficiency of HEV is improved, and the SOC of the battery is kept in balance during different urban driving cycles.

Drivers must communicate with other road users to make their intentions clear, thereby enhancing the quality of the driving experience, improving safety on the roads and avoiding accidents. This interaction can be made either formally using legal signals approved by legislative bodies (e.g. use of indicators), or informally (e.g. hand gestures). However, this informal interaction may not be clearly understood by all drivers, and may lead to stress, strong emotional responses or aggressive driving behaviour. Moreover, a single informal interaction, e.g. flashing the headlights, can have several different meanings such as “Your headlights are on”, “Thank you”, or “I want to overtake you”, depending on the situation. Driver interaction could be enhanced by an electronic driver-to-driver communication device (DDCD), which would allow motorists to exchange messages with each other. The technology associated with connected vehicles could be used for the design of this communication device. For example, wireless devices and sensors already allow vehicles to exchange information with other vehicles (V2V) and road infrastructure (V2I) at any time. This PhD research initially introduces a driver-to-driver communication framework depicting a set of variables or factors that have a decisive effect on the communication process. The framework is also comprised of a task analysis for the DDCD. The framework is later expanded to include a specific set of design recommendations linked back to the variables that affect the communication process. These recommendations are specifically related to the DDCD and are based on a review of the literature and results from empirical studies conducted as part of the PhD. A mixed-methods approach was adopted in this research to elicit opinions and attitudes of drivers, including interviews, observations, a workshop with academic experts and questionnaires. In total, five studies are described in the thesis, with STUDY A being an exploratory investigation on the feasibility of the DDCD. The second and third studies focused specifically on the task of receiving messages, with academic experts (STUDY B) and with regular drivers (STUDY C). A fourth study (STUDY D) involved on-road trials to investigate how drivers would identify a vehicle to send a message to. The final experiment (STUDY E) consisted of an evaluation in a driving simulator of a low-fidelity prototype of the communication device to send messages. The studies were based on a set of driving communication scenarios, which facilitated the exploration of potential issues with the use of a proposed technology before implementation. The scenarios represented different examples of how, why and when drivers might communicate with one another, and were used as the focal point with study participants. The findings from this research indicate that drivers would be willing to use an electronic communication device in situations directly related to the road context in which there is a decisive effect on their safety or that may alter their driving behaviour, such as a problem with their vehicle or a hazard on the road. There are many factors investigated in this research that have a significant effect on drivers’ communication process. These factors include, but are not limited to, time criticality, trust issues in message content, the effect of passengers, sender anonymity and the general purpose of communication. These research findings will significantly contribute to the limited academic research currently available on social and connected vehicles and can also provide invaluable information for the automotive industry.

Electric Vehicles (EV) and Hybrid Electric Vehicles (HEV) are seen as solutions to meet the rising demand of consumers whilst overcoming challenges such as dependency on fossil fuels and carbon dioxide emissions. The success of these vehicles is highly dependent on reliable and efficient Energy Storage Systems (ESS). In order to build a reliable and efficient ESS system, a cylindrical lithium-ion cell is the most prominent choice since it has good energy density and favourable charging and discharging properties. Arrays of lithium-ion cells are connected in series and parallel to build the high power ESS system. These connections are realised by Battery Tab Joints. The durability and performance of the ESS system depends on the battery tab joint. Hence, the battery tab joint should be capable of enduring the static and dynamic mechanical loads as well as the electrical load. In order to understand battery tab joint behaviour, the performance (both mechanical and electrical properties) of battery tab joints were investigated under mechanical and electrical load. Resistance Spot Welding (RSW) was selected as the joining technique. RSW process parameters were optimised to achieve consistent nugget size and weld quality. The materials selected for investigation were nickel plated steel and nickel plated copper. In order to understand the mechanical and electrical behaviour of spot welded joints under mechanical and electrical load a test environment was designed to allow quasi-static and dynamic (fatigue) testing of tensile coupons and lap-shear welded specimens under electrical load. Temperature change and electrical properties were recorded during the tests. During fatigue test of lap-shear joints for different electric current load, it was found that the change in electric contact resistance (ECR) ratio up to the point of fatigue failure of joints was 0.1 and 0.2 for steel and copper respectively. Importantly, it was suggested that the change in ECR could act as a prediction mechanism for joint failure in a real ESS. It was found that electric current load has no observable effect on fatigue life of the battery tab joints. A computer-based model was developed to simulate weld damage and it was found to be in good agreement with experimental results. The effect of preload arising during battery pack manufacture was investigated. It was found that preload (without electric current load) had significant impact on fatigue performance of the battery tab joints.

The current drive to generate energy from sustainable renewable resources has led to an increased interest in generating power through exploiting the kinetic energy in faster flowing tidal streams. Much of the knowledge gained from the development of wind turbines has been applied to the tidal stream turbine. However, the hostile marine environment introduces new technological challenges. The tidal turbine operates under highly unsteady, turbulent flow conditions and the occurrence of marine biofouling adds further complication to the issue. The main objective of the present work is to advance the understanding of the effect marine fouling has on the unsteady hydrodynamic loading and performance of tidal turbine blade sections. To investigate this challenging fluid phenomenon, a series of two-dimensional static and unsteady experiments were designed and conducted in the dynamic stall test rig at the University of Glasgow's Handley Page wind tunnel facility. The test matrix was constructed to cover the full operating envelope of a blade from MW-scale turbines, and included three thicker, cambered blade sections from two radial positions on the blade - a NACA 63-619 and two proprietary AHH designs. Chordwise integrated force and pitching moment coefficients were obtained from surface pressure measurements for three representative blade fouling configurations: an aerodynamically clean baseline; a light level of widely distributed microfouling roughness; and the addition of macrofouling with a single instrumented barnacle protuberance. This work has generated what is believed to be a unique database of unsteady tidal turbine blade section performance and, more importantly, the negative impact marine biofouling is likely to have on these investigated parameters. The approach followed through the work has been to assess the impact of marine biofouling on the individual blade sections and then assess the consequences of marine biofouling on the turbine by combining the blade section findings in a BEMT numerical performance model.

Self-pierce riveting (SPR) is the core joining technology used by Jaguar Land Rover (JLR) to join aluminium & mixed material body in white (BIW). Currently, the application of this process has a serious constraint to the business due to the high investment and intensive labour required by physically testing joint feasibility. This is a critical issue especially where different stacks need to be joined by one SPR gun. In this case, the selection of a common rivet/die combination which suits different material stacks requires labour intensive work that in some cases can create long delays during a vehicle development and commissioning. In this context, the development of a simulation technique, based on Finite Element Analysis (FEA), could allow virtual assessment of the manufacturing feasibility of a joint. This will enable significant business benefits including: saving time, costs and materials requirement for the experimental trials. Three major challenges need to be addressed: short CPU time, accuracy and robustness in order for its application in a manufacturing environment. To achieve these objectives, detailed numerical methods capable of reproducing the key factors affecting the experimental process like tooling, boundary conditions and material plastic deformation are developed. For the first time, a thermo-mechanical finite element model for simulation of the SPR process has been proposed. This allowed consideration of the increase in temperature due to friction and plastic deformation generated during the rivet insertion. The effect of thermal softening and strain hardening were characterized for the development of the substrate material model and their influence on the numerical simulation was assessed. This study has been validated via production line data and a significantly high level of correlation between simulation and experimental data for over 1000 joints representative of a vehicle platform has been achieved. The application of the developed simulation technique will enable several business benefits such as significant reduction of engineering time and costs in contrast to the experimental procedure. These advantages allow a smooth implementation of the SPR process in a JLR production line by providing engineering recommendations rapidly and consistently. All these features, combined with accuracy and robustness have enabled the application of the developed tool into JLR business.

Active pedestrian safety systems can help to significantly increase pedestrian road safety, but must be tested very carefully before used in series application. Since there is usually a very small amount of time to prevent the collision, the activation of an emergency brake is always a critical decision. On the other hand, of course, false triggerings must be prevented. Aiming to increase pedestrian and vehicle safety, this thesis presents a novel approach for the test of active pedestrian safety systems. From the question "What is needed to test and compare future active pedestrian safety systems?" are resulting the following questions: 1. What are the significant characteristics of real pedestrians? 2. How can this features be mapped to a test system? This thesis presents characteristic features of pedestrians from the perspective of automotive surround sensors and introduces a novel test system approach including a realistic pedestrian dummy which is able to replicate those characteristics. Furthermore it introduces a novel active pedestrian safety test methodology, based on the variation of target characteristics, environmental conditions and driver behaviour. The proposed pedestrian dummy was set up in real size and tested on the test track in vehicle tests. A video of the described test and the novel pedestrian dummy can be seen here: https://youtu.be/eF5IkqsknBE

Advanced Driver Assistance Systems (ADAS) aids the driver by providing information or automating the driving related tasks to improve driver comfort, reduce workload and improve safety. The vehicle senses its external environment using sensors, building a representation of the world used by the control systems. In on-road applications, the perception focuses on establishing the location of other road participants such as vehicles and pedestrians and identifying the road trajectory. Perception in the off-road environment is more complex, as the structure found in urban environments is absent. Off-road perception deals with the estimation of surface topography and surface type, which are the factors that will affect vehicle behaviour in unstructured environments. Off-road perception has seldom been explored in automotive context. For autonomous off-road driving, the perception solutions are primarily related to robotics and not directly applicable in the ADAS domain due to the different goals of unmanned autonomous systems, their complexity and the cost of employed sensors. Such applications consider only the impact of the terrain on the vehicle safety and progress but do not account for the driver comfort and assistance. This work addresses the problem of processing vision sensor data to extract the required information about the terrain. The main focus of this work is on the perception task with the constraints of automotive sensors and the requirements of the ADAS systems. By providing a semantic representation of the off-road environment including terrain attributes such as terrain type, description of the terrain topography and surface roughness, the perception system can cater for the requirements of the next generation of off-road ADAS proposed by Land Rover. Firstly, a novel and computationally efficient terrain recognition method was developed. The method facilitates recognition of low friction grass surfaces in real-time with high accuracy, by applying machine learning Support Vector Machine with illumination invariant normalised RGB colour descriptors. The proposed method was analysed and its performance was evaluated experimentally in off-road environments. Terrain recognition performance was evaluated on a variety of different surface types including grass, gravel and tarmac, showing high grass detection performance with accuracy of 97%. Secondly, a terrain geometry identification method was proposed which facilitates semantic representation of the terrain in terms of macro terrain features such as slopes, crest and ditches. The terrain geometry identification method processes 3D information reconstructed from stereo imagery and constructs a compact grid representation of the surface topography. This representation is further processed to extract object representation of slopes, ditches and crests. Thirdly, a novel method for surface roughness identification was proposed. The surface roughness descriptor is then further used to recommend a vehicle velocity, which will maintain passenger comfort. Surface roughness is described by the Power Spectral Density of the surface profile which correlates with the acceleration experienced by the vehicle. The surface roughness descriptor is then mapped onto vehicle speed recommendation so that the speed of the vehicle can be adapted in anticipation of the surface roughness. Terrain geometry and surface roughness identification performance were evaluated on a range of off-road courses with varying topology showing the capability of the system to correctly identify terrain features up to 20 m ahead of the vehicle and analyse surface roughness up to 15 m ahead of the vehicle. The speed was recommended correctly within +/- 5 kph. Further, the impact of the perception system on the speed adaptation was evaluated, showing the improvements in speed adaptation allowing for greater passenger comfort. The developed perception components facilitated the development of new off-road ADAS systems and were successfully applied in prototype vehicles. The proposed off-road ADAS are planned to be introduced in future generations of Land Rover products. The benefits of this research also included new Intellectual Property generated for Jaguar Land Rover. In the wider context, the enhanced off-road perception capability may facilitate further development of off-road automated driving and off-road autonomy within the constraints of the automotive platform.

This thesis deals with the control system of two-seater aircraft corresponding to CS-23 Level 2. First load calculations of each control surface are performed using the proses described in previous CS-23 regulation. This load is calculated trought the steering mechanism to control elements in cockpit. The resulting forces on the control elements are compared with the requi-rements in CS-23. Because the steering forces meets requirements is not necessary to propose changes in steering kinematics. However, there are further suggested ways of adjusting the control in case the external load would increase during further development of the airplane. At the end, the strength calculation of entire mechanism is preformed.