الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
ABSTRACT
This thesis aims to model and study the design of autonomous vehicle longitudinal and lateral controllers. Such a modelling process simulates human driver behaviour with consideration of real vehicle dynamics’ characteristics during standard manoeuvres. A three-degree-of-freedom bicycle model is constructed to represent longitudinal and lateral vehicle motion. Moreover, a sophisticated mathematical traction model which includes an engine, automatic transmission, and non-linear magic formula tire models are implemented for the simulation of vehicle longitudinal dynamics. Furthermore, the target of designing the vehicle lateral control is to minimize lateral deviation and yaw angle errors. However, for improving vehicle lateral performance in terms of manoeuvrability and stability as well, the rear steering advantage is used to decrease the lateral motion errors as possible. To achieve these tasks, two approaches are designed and implemented to guide vehicle lateral motion. On one hand, a strategy of using fuzzy logic front steering and LQR-based rear steering controllers is presented. On the other hand, a second strategy of using LQR based controller for adjusting both front and rear steering angles is also executed to achieve the same purpose to promote the achievement of targeted aims. The lateral controller steers the vehicle wheels to follow the pre-defined path while a PID longitudinal controller is used in all cases to maintain the desired speed through control of the engine throttle. Path-tracking simulation is executed through enjoining a referenced safe path to pass a simulated track based on ISO 3888 double lane change manoeuvre. A performance comparison is set in the case of using the front steering only, and the proposed strategies. Both longitudinal and lateral controllers’ simulation results achieved the required performance based on lateral deviation, yaw angle, front steering angle, and vehicle speed. Additionally, the lateral deviation is minimized according to the reference simulated path through the rear steering controller while decreasing vehicle yaw rate and slip angles for front and rear tires.