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This study reports the influence of vehicle characteristics on the cornering behaviour of a narrow-tilting vehicle (NTV). A single-track vehicle dynamics model was used for all the analyses and linear and nonlinear tyre models were applied. Vehicle tilting and roll were assumed from wheel camber, only considered in the front axle, and front motorcycle and rear passenger-car tyre characteristics were considered. Handling and stability analysis was performed in steady-state and transient cornering conditions. Moreover, rear steering, variable track width and roll effects were discussed on vehicle handling and stability properties. The study results showed an understeer vehicle behaviour for all the operational speeds of the vehicle. Contrary to the vehicle responsiveness, which was obtained to increase with increasing speed, the stability of the handling steady- state solutions was observed to decrease the higher the speed. On another hand, the rear steering system was obtained to produce more lateral slip than the front steering system in steady-state conditions and less dynamic response to any disturbance or sudden steering change. Furthermore, higher tilting angle limits were associated with wider tracks in a vehicle stable range. Finally, more lateral force resulting from camber thrust was obtained to increase yaw rate. This was perceived in the vehicle trajectory results, which showed accentuated vehicle turning

This paper investigates the fundamentals of motion planning for minimizing motion sickness in transportation systems of higher automation levels. The optimum velocity profile is sought for a predefined road path from a specific starting point to a final one within specific and given boundaries and constraints in order to minimize the motion sickness and the journey time. An empirical approach based on British standard is used to evaluate motion sickness. The trade-off between minimizing motion sickness and journey time is investigated through multi-objective optimization by altering the weighting factors. The correlation between sickness and journey time is represented as a Pareto front because of their conflicting relation. The compromise between the two components is quantified along the curve, while the severity of the sickness is determined using frequency analysis. In addition, three case studies are developed to investigate the effect of driving style, vehicle speed, and road width, which can be considered among the main factors affecting motion sickness. According to the results, the driving style has higher impact on both motion sickness and journey time compared to the vehicle speed and the road width. The benefit of higher vehicle speed gives shorter journey time while maintaining relatively lower illness rating compared with lower vehicle speed. The effect of the road width is negligible on both sickness and journey time when travelling on a longer road. The results pave the path for the development of vehicular technologies to implement for real-world driving from the outcomes of this paper., QC 20220421

Automated vehicles are expected to push towards the evolution of the mobility environment in the near future by increasing vehicle stability and decreasing commute time and vehicle fuel consumption. One of the main limitations they face is motion sickness (MS), which can put their wide impact at risk, as well as their acceptance by the public. In this direction, this paper presents the application of motion planning in order to minimise motion sickness in automated vehicles. Thus, an optimal control problem is formulated through which we seek the optimum velocity profile for a predefined road path for multiple fixed journey time (JT) solutions. In this way, a Pareto Front will be generated for the conflicting objectives of MS and JT. Despite the importance of optimising both of these, the optimum velocity profile should be selected after taking into consideration additional objectives. Therefore, as the optimal control is focused on the MS minimisation, a sorting algorithm is applied to seek the optimum solution among the pareto alternatives of the fixed time solutions. The aim is that this solution will correspond to the best velocity profile that also ensures the optimum compromise between motion comfort, safety and driving behaviour, energy efficiency, journey time and riding confidence., QC 20220812

Due to the need of higher control strategies for the viability of autonomous vehicles on an ever changing environment, this thesis will cover the development of an autonomous vehicle simulation considering longitudinal control from an Adaptive Cruise Controller (ACC) and lateral control from a Lane Keeping Assist (LKA) controller. The implementation of the control model and code will be made in Simulink and Matlab and simulated using the virtual testing software IPG CarMaker. The vehicle simulated is a Volkswagen Beetle equipped with two sensors. For the ACC, a radar sensor is placed at the front bumper providing relevant information about the preceding traffic object, in particular, the presence of an object and the relative distance and velocity. On the other hand, a line sensor is placed behind the windshield rear-view mirror to monitor the lane bounds and provide the relative position of the lane with respect to the sensor. A line sensor, essentially, emulates a camera sensor with some image processing layers capable of reliably detect lines. To enable longitudinal control, the Intelligent Driver Model calculates the desired acceleration by comparing the desired ego car speed with the actual value. Also, it compares the actual relative distance to a desired distance calculated by considering a standstill gap, a desired time gap at a certain speed and the relative velocity with a preceding vehicle. This model though does not precisely track the relative distance when approaching the desired speed. To address this issue, an algorithm that enables this functionality is implemented monitoring the relative velocity beyond the speed limit to avoid undesired driving conditions. On the other hand, lateral control is achieved by considering both degrees of freedom of a four wheeled vehicle, yaw angle and lateral deviation from the lane centreline. For this, Catmull-Rom curves are fitted in the lane centre to measure both magnitudes and compare them to their ego vehicle’s