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Recently complex geometry and detailed Finite Element (FE) models have been used to capture the true behaviour of the structures for crashworthiness. Such model complexity, detailed FE model, high non-linearity of crash cases and high number of design variables for crashworthiness optimisation add to the required computational effort. Hence, engineering optimisation problems are currently highly restricted in exploring the entire design space and including the desired number of design parameters. Hence it is advantageous to reduce the computational effort to fully explore the design alternatives and also to study even more complex and computationally expensive problems. This thesis presents an efficient robust shape optimisation approach via the use of physical surrogate models, i.e. sub-models and models derived for the Equivalent Static Loads Method (ESLM). The classical simultaneous robust design optimisation (RDO) approach (where robustness analysis of each design is assessed) is modified to make use of the physical surrogate models. In the proposed RDO approach, design optimisations are made using sub-models and robustness analyses are made using either non-linear dynamic analysis or ESLM. The general idea is to approximate the robustness of designs at the start of the optimisation (using ESLM) and use accurate robustness evaluations (via non-linear dynamic analysis) towards the end of the optimisation where the optimisation has already found interesting regions of the design space. The approach is validated on crashworthiness design cases.

The objective of this study was to develop a new Steer Tilt Control (STC) algorithm inspired by real driver behaviour and to test it in simulation with an experimentally validated non-linear vehicle model. In order to develop an exhaustive simulation model of the vehicle and to process experimental data correctly, a large number of modelling aspects were taken into consideration. The objective of the study was to identify the unique kinematics of a three-wheeled tilting vehicle and determine the importance of the kinematic effects on the vehicle system. In order to fully understand this unique class of vehicle, the effect of the driver’s mass on the vehicle inertia’s and the effect of the tilting on the vehicle’s yaw inertia were considered. A wide-ranging expression for the driver’s perceived acceleration was derived and the roll dynamics of the non-tilting part of the three-wheeled tilting vehicle assembly were modelled. The steering torque of the vehicle as fully analysed and, using the simulation model, methods to model the effect of a crosswind on the vehicle, to test the effect of driving up or downhill, and to determine the effect of road camber on the vehicle dynamics were considered. To create a better understanding of the control task, road experiments were carried out using an instrumented tilting three-wheeler to investigate the driver steer inputs necessary to both balance the vehicle and follow a fixed trajectory. The experimental results demonstrated that the drivers’ steering inputs varied even though they had to complete identical tasks. This result confirmed that there are multiple ways to control the roll of the vehicle. The results also showed that the tilt angle always led the steering angle and for a transient manoeuvre, the tilt angle was larger than the balanced tilt angle at the start of the manoeuvre and smaller than the balanced angle at the end of the manoeuvre. The next step in the investigation was the development of a comprehensive non-linear dynamics model of a tilting three-wheeler including a tyre model and a driver model. A new method was developed to estimate the parameters of a Magic Formula Tyre model using the road testing data. The vehicle and tyre model were validated using data from a range of test runs. The importance of a driver in the loop was recognised and the elements of a driver trajectory-tracking model were studied. The aim was to develop a driver model that demonstrated good i tracking and some similarity to real driver behaviour. The final model used the yaw rate demand to determine an anticipatory control steer angle and the current heading error and the vehicle’s lateral position error measured in the vehicle’s local axis system to make small steering adjustments. The STC method based on Proportional Integral Derivative (PID) control was tested with the vehicle model to determine its performance with the non-linear dynamics and the driver in the loop. It was shown that the driver model had the tendency to act against the STC and that the two could only act simultaneously for a very limited range of demand trajectory and velocity combinations. The crosswind, hill driving, and road camber models were combined with the vehicle simulation without a driver but with the PID based STC. The simulations showed that these environmental factors made the control task significantly more difficult. More importantly, it showed that these factors demanded an increased number of vehicle states to be fed back to the controller. A new algorithm for STC was developed using the full vehicle and driver model. One of the criteria was that the control algorithm had to be realizable in practice. The resulting controller was a logic algorithm that would choose an action based on the steering angle and velocity and the vehicle speed with online gain adjustment based on direction and order of magnitude of the perceived acceleration. The basis of the control was adjustment of the driver's steering input and it was shown that the vehicle's deviation from the driver's intended path was minimal.

When engaging a new gear in an automated manual transmission (AMT) the gear needs to be synchronized with the main shaft's angular velocity in the gearbox. This is so that the parts can be connected through a cog wheel and torque can be transferred. To synchronize the angular velocities, mechanical synchronization components can be used. These components synchronize the velocities during the engagement and can be used with larger differences in angular velocities. Should no mechanical synchronization components be used it puts higher demands on the components rotating at similar velocities to avoid mechanical wear and ensure that the gear can be engaged. In today's systems without mechanical synchronization components the gear is engaged when the angular velocities are within a certain difference. This leads to random angle connections between the cogs and gaps that are to be engaged on the gear and main shaft. This can lead to extended or incomplete engages should the components connect cog to cog. This thesis evaluates the possibility to control the angle at which the components connect by using existing sensor signals in the studied system and known parameters. A model of the system is created and simulated to evaluate the probability of predicting the system over the gear engage. Results indicate that it is possible to predict the connection angle close enough to its real value so that a control strategy could be implemented to control the angle to some level.

Initiatives to electrify urban transport promote the purchase and usage of Electric Vehicles (EVs) and have great potential to mitigate the pressing challenges of climate change, energy scarcity and local air quality. Transportation electrification is a huge innovation and could directly and indirectly impact and/or be impacted by several urban sub-systems. This project develops an agent-based integrated framework for investigating how the EV market expands in the context of urban evolution at the micro scale, and assessing the potential impacts of the market expansion on the environment, power grid system and transport facilities, considering the interactions and dynamics found there. The framework may be useful for stakeholders, such as governments, as an aid to decision making. The integrated framework, SelfSim-EV, is updated from a Land Use and Transport (L-T) model, SelfSim, by incorporating several EV-related modules, including an EV market model, an activity-based travel demand model, a transport facility development model and a social network model. In order to somewhat present the behavioural rules of some key agents in SelfSim-EV, two questionnaire surveys on individual EV travel and purchase behaviours were delivered to members of the general public in Beijing, and semi-structured interviews with EV stakeholders were also carried out. The collected data was analysed using discrete choice models and Geographic Information System (GIS). SelfSim-EV was fully tested within two test cases in China, Baoding (a medium-sized city) and Beijing (the capital of China): first, parameter Sensitivity Analyses (SAs) were carried out to test SelfSim-EV within the test case of Baoding from both global and local perspectives, investigating the relationships between the 127 model parameters and 78 outputs of interest; Then SelfSim-EV was further tested within the case study of Beijing, involving in model initialisation, calibration, validation and prediction. Specifically, the SA results were used to calibrate SelfSim-EV in Beijing from 2011 to 2014 by matching various observed and simulated data types at both city- and district-levels, and the calibrated SelfSim-EV model was further validated against historical data in 2015. Then the future of EVs in Beijing was explored within a Reference Scenario (RefSc) from 2016 to 2020. Due to the model uncertainty in future events, several "what-if" scenarios were set up with the SelfSim-EV Beijing model to explore how three typical types of driving factors, namely policy, technology and infrastructure, may influence the EV market expansion at both aggregate and disaggregate levels. The results indicate that policies tend to be more influential than technologies and infrastructures in terms of EV penetration rates. RefSc eventually shows some improvement in total emissions, however, boosting sales of EVs (particularly PHEVs) in the wrong way could have negative impacts. Charging demand accounting for around 4% of total residential electricity demand in 2020 may put slight pressure on the power grid system in RefSc, and it does not increase linearly as the EV sales rise. Slow charging posts appear to be necessary, whereas fast charging facilities seem to contribute slightly to the EV market expansion and thus may be not necessary at the current stage.

Pollution levels in urban areas continue to rise, with transportation being the number one cause. As cities ban fossil fuel cars access to the city center, this project looks at the delivery of packgaes from internet purchases. A three-wheeled, human-powered and electrically assisted vehicle is designed. This vehicle is dsigned to work together with last-mile logistics. A scientific design process was carried out to define the stakeholders, competition and requirements of the project, among others.The results yielded a semi-finished vehicle, comprising of the frame, general design, FEA analysis, delivery system and an optimization process for the frame. Future work includes economical or social study, design of the brakes and gear system or a design of the frame-cabin connection.

A lightweight chassis for a battery electric vehicle being developed at the University of Waikato was required. The chassis was designed around a predetermined body shape and suspension setup. A chassis, built from 20mm thick aluminium honeycomb sandwich panel, was designed and built to LVVTA standards allowing the car to be driven on public roads. The chassis weighs a little over a third the mass of a mass production car chassis. The car has been driven over 1800km with only one minor problem, indicating the chassis is reliable and well suited to its purpose. Titanium aluminide properties were researched to identify where titanium aluminides could be used in an automobile. Titanium aluminides have a specific strength and stiffness near to steel yet only half the density making it an ideal replacement for steel components. Automotive applications identified that could benefit from the use of TiAl include valves, brake rotors and inside 'in-wheel' electric motors.

Collisions between animals and motor vehicles are frequent and often result in animal mortality. In Australia, macropods are regular victims of these collisions. This has serious implications for animal welfare and conservation as well as aesthetics and tourism. Collisions with large animals and secondary collisions caused by the presence of animals on road easements, can lead to serious personal injury and property damage. A range of mitigative measures to prevent animal-vehicle collisions exists, but no single measure can be fully effective and the efficacy of many mitigation measures remains untested. An integrated management approach, employing many mitigative techniques is required to reduce vehicle-animal collisions. Repellents have recently been identified as a potential mitigative measure for reducing vehicle-animal collisions. The aim of this study was to identify the potential role of repellents in reducing macropod-vehicle collisions in New South Wales. This required the identification and assessment of potential repellents since research investigating repellents in an Australian context is scant. Macropus rufogriseus banksianus was selected as a test species for this research as a high abundance of this species exists in southeastern Australia and it is a common victim of roadkill in New South Wales. Preliminary screening trials of four potential macropod repellents highlighted the utility of two of the substances: Plant Plus, a synthetic compound based on the chemistry of dog urine; and a formulation consisting of chicken eggs. Feeding by M. rufogriseus banksianus was significantly reduced when these substances were applied near feed trays. Modest results were also detected for Δ3-isopentenyl methyl sulfide (a constituent of fox urine), while a commercial animal repellent (SCAT® Bird and Animal Repellent) was ineffective in altering feeding by M. rufogriseus banksianus. A barrier trial conducted with the two most successful repellents indicated that Plant Plus was a more effective macropod repellent then the egg formulation. Plant Plus displayed qualities of an area repellent and elicited a stronger response from M. rufogriseus banksianus when compared to the egg formulation. Further captive trials determined that the habituation of response to Plant Plus by M. rufogriseus banksianus was minimal after six weeks of constant exposure and Plant Plus retained repellent properties after exposure to ambient environmental conditions for at least ten weeks. Field trials to establish the effectiveness of Plant Plus with free ranging macropods (M. rufogriseus banksianus and M. giganteus) were unsuccessful due to methodological limitations stemming from high background variance in observed responses, equipment failure and site disturbance from outside influences. The potential role of Plant Plus as a repellent for managing macropod-vehicle collisions was highlighted by the captive trials. However, several factors requiring further research were identified. This included assessing the repellent abilities of Plant Plus in the field and further defining the properties of Plant Plus with captive trials. The effects of Plant Plus on non-target species and an assessment of potential environmental impacts also requires attention. Research assessing the potential role of repellents in other management contexts in Australia would be beneficial and the identification and assessment of repellents for other species should proceed. However, in the context of assessing repellents for use in the management of vehicle-macropod collisions, immediate focus should concentrate on extending the research to assess the effects of Plant Plus with other species of large macropod, and assessing if Plant Plus can reduce the numbers of macropods in road easements.

Fuel represents a major proportion of road transport expenditure and it is likely that this proportion will increase. At typical road speeds approximately half of the total fuel used is consumed in overcoming aerodynamic drag, hence the determination and reduction of aerodynamic drag is of considerable importance. This is normally performed by scale testing in wind tunnels with relatively smooth flow. When modelling an atmospheric crosswind in the tunnel the relative air direction is generated by yawing the model at an angle to the oncoming flow. This procedure does not reproduce the inherent turbulence in atmospheric winds. A review of the literature showed a poor correlation between road and wind-tunnel results often attributed to the lack of tunnel turbulence. The work presented herein involves road and wind-tunnel tests to investigate these discrepancies and aims to improve the accuracy of wind-tunnel modelling for commercial vehicles. Wind-tunnel and on-road tests which determine drag coefficient reductions from aerodynamic devices fitted to commercial vehicles are described. Two series of road tests utilised pairs of commercial vehicles: International Harvester Australia low-forward-entry articulated vehicles with maximum road-legal size containers and Isuzu rigid (box-van) vehicles fitted with cuboid containers. Drag coefficient reductions were calculated from fuel meter readings in the trucks and measurements of yaw angle and relative velocity from an instrumented chase car. Tunnel testing was performed on scale vehicles in the Royal Melbourne Institute of Technology (RMIT) Industrial Wind Tunnel in relatively smooth flow (longitudinal intensity = 1.7%). Large differences between road and tunnel drag coefficients at high yaw angles were found. The on-road turbulent wind environment was measured utilising a vehcle instrumented with mast-mounted cross-wire and propeller-vane anemometers. Atmospheric mean wind speeds of 1 m/s to 9 m/s, aligned at various angles to .the road direction, were encountered and data were taken with the vehicle stationary and moving at 27.8 m/s (100 km/h). Longitudinal and lateral intensities and spectra were calculated thus providing new information on the wind environment for vehicles. A mathematical model of the turbulence intensities perceived by a moving vehicle was developed. This utilised atmospheric wind data obtained whilst the vehicle was stationary to predict moving vehicle data. Measured and predicted intensities for the moving vehicle were in good agreement for roads with no local roadside obstructions (eg. trees) thus validating the model, but the obstructions increased data scatter and augmented the lateral intensities by typically 30%) with little change in the longitudinal intensities. Peaks in the longitudinal and lateral spectra for the moving vehicle were at approximately 1.0 Hz and most of the energy was contained between 0.1 Hz and 10 Hz. Subsequent tunnel tests were performed using five levels of grid-generated turbulence and the mathematical model was used to predict the on-road data from tunnel tests. Better agreement was found at high yaw angles when the correct longitudinal intensities were used. However the scales of turbulence in the tunnel were too short for correct modelling. Flow visualisation studies over the model and full-size cab roofs indicated differences in flow patterns that were attributed to Reynolds number differences. The mathematical model and measurements described in this thesis showed that high yaw giigles are always accompanied by relatively high turbulence intensities and it was concluded that the modelling of turbulence characteristics for commercial vehicles is more important than other modelling parameters such as a moving ground. Most major vehicle aerodynamics tunnels have very low turbulence levels (longitudinal rms intensities commonly less than 0.5%) whereas measured on-road values of 2% to 5% are typical (with higher values of lateral intensities). It is therefore recommended that for vehicle aerodynamic generally more attention be paid to correctly modelling the intensities and scales of turbulence in wind tunnels and understanding the effects of typical turbulence characteristics on vehicle drag.

This research contributes to the existing body of knowledge relating to crash compatibility (the minimisation of injury risk faced by all participants involved in a collision in traffic). The research focuses on the topic of structural interaction in collisions involving passenger vehicles, a phenomenon describing the efficiency of energy dissipation within existing deformation-zones of a passenger vehicle during a collision. A new definition for structural interaction was developed and several metrics to evaluate structural interaction and compatibility in car-to-car collisions were proposed, based on the commonly known Equivalent Energy Speed (EES) metric. The new EES metrics describe equivalent closing velocities for a given collision based on the energy dissipated within the front-ends (EESFF) and the entire structure (EESVV) of both vehicles involved in a head-on collision. These metrics form the basis of the new knowledge generated by this research. Additionally, a new method was developed to measure the amount of energy dissipated through structural deformation in a collision, based on accelerometer readings. This method was applied to several experimental and simulationbased car-to-car collisions and the validity of the method was proven. Based on the energy dissipation which occurred in the car-to-car collisions analysed, the degree of compatibility reached and the level of structural interaction which occurred in each collision was evaluated by applying the newly developed EESFF and EESVV metrics. Thie research also investigates the assessment of vehicles' structures in a standardized procedure with a view to improving structural interaction in the real-world. Several fixed barrier crash tests have been proposed in different configurations and with different assessment criteria. All assessments aim to evaluate the geometrical characteristics of the front-ends of passenger vehicles. A set of factors required from a compatilibility assessment focused on assessing vehicle geometry were identified. The proposed compatibility assessment procedures were evaluated based on their ability to predict the potential for structural interaction offered by passenger vehicles.