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This paper presents a comprehensive investigation aimed to assess the effect of tire inflation pressure on the fuel consumption of a typical 4×4 off-road vehicle over unprepared soft terrains. For this purpose, a fourteen-degrees-of-freedom (14-DOF) full parametrized vehicle model is employed and numerically simulated in MATLAB/Simulink™ environment. This model is intended to consider all the rotational dynamics and compliances of all-wheel-drivetrain aggregates using SimDriveline™ toolbox including engine, transmission, differentials, shafts and wheels. Numerous simulations are carried out to examine both the tractive efficiency and fuel consumption considering all power losses in transmission, terrains and tire slippage over different operating conditions such as terrain’s mechanical properties, tire weight distribution and drivetrain configurations (open or locked center differential).

This paper investigates the effect of tire inflation pressure on the directional stability of All Wheel Drive (AWD) vehicles during high-speed off-road maneuvers over different soft terrains such as loam, sand and clay. For this purpose, a fourteen-degrees-of-freedom (14-DOF) full parametrized vehicle model is employed and numerically simulated in MATLAB/Simulink environment to represent the full vehicle body dynamics such as roll, yaw and pitch motions. In order to calculate tire forces and moments over deformable terrains, the AS2TM Soft Soil Tire Model was successfully integrated with the vehicle model which enabled the possibility of changing tire pressure and consequently investigate its effect on vehicle dynamics. Numerous simulations are carried out to examine vehicle handling in case of different tires inflation pressure during steady state turning maneuvers such as ramp steer input.

This paper presents a comprehensive investigation aimed to improve wheeled vehicles’ traction performance by properly controlling tire inflation pressure while driving over different terrains. A four-degrees of freedom (4-DOF) parametrized quarter vehicle model is derived and numerically simulated in MATLAB/Simulink environment to estimate the traction performance of a single pneumatic tire over different terrains such as clay, loam and sand. Numerous simulations are carried out to investigate the effect of tire inflation pressure on traction performance considering different tire loading conditions and soil terrains. Simulation results showed significant improvements in vehicle traction performance in terms of maximum tractive efficiency and maximum drawbar pull by reducing tire inflation pressure.

This paper presents an advanced control system, which integrates three fuzzy logic controllers namely; Direct Yaw-moment Control (DYC), Active Roll-moment Control (ARC) and Active Front Steering (AFS) to enhance vehicle cornering and overturning stability. Based on a well-developed and validated fourteen degree of freedom (DOF) full vehicle model with non-linear tire characteristics, a reference 3-DOF yaw-roll plane vehicle model is introduced to control yaw rate, sideslip angle, and roll angle of the vehicle body. The control actions of both direct yaw and active roll moments are performed by generating differential braking moments across the front wheels, while the control action of the active steering is performed by modifying the steering wheel angle. Different standard cornering tests are conducted in MATLAB / Simulink environment such as J-turn, fishhook and lane change maneuvers.

This paper presents an integrated experimental and simulation investigation which is conducted on a series hybrid electric vehicle. The mathematical model is simulated in two distinct environments; MATLAB/Simulink and GT-Suite. An experimental test rig is devised in order to measure the vehicle performance including wheeled-chassis dynamometer. Components consumed powers, vehicle speed, engine revolution, fuel consumption and consumed energies are all measured in real time and the results are used to verify the numerical modelling work. For optimizing the performance of the vehicle, a rule based control algorithm is proposed and applied to the model using Stateflow environment. Many sequential-decision logic-based rules are graphical coded to operate the internal combustions engine at its most fuel efficient modes.