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Vehicle Handling performance depends on many parameters. One of the most important parameters is the dynamic behavior of the steering system. However, steering system had been enhanced thoroughly over the past decade where Active Front Steering (AFS) is now present and other system as Active Independent Front Steering (AIFS) is currently in the research phase. Actually, AFS system adopt the front wheels’ angles base on the actual input steering angle from the driver according to vehicle handling dynamics performance. While, the AIFS controls the angle of each front wheel individually to avoid reaching the saturation limits of any of the front wheels’ adhesion. In this paper modeling and analysis of an AIFS is presented with Tire Work Load (TWL) based controller. Magic Formula tire model is implemented to represent the tire in lateral slip condition.

The cottonseed oil, soybean oil and their methyl esters have been used as a pilot fuels for dual fuel engine running on the LPG as the main fuel. A variable compression research diesel engine has been converted to run on dual fuel of LPG and a pilot fuel derived from the renewable liquid fuels above. The engine has been instrumented to measure the combustion pressure, crank angles, exhaust temperature, flow rates of air, pilot fuel and gaseous fuel. The effects of changing the following parameters have been studied: the mass of pilot fuel, the mass of gaseous fuel, the pilot fuel injection timing, engine speed and the pilot fuel type. Five different pilot fuels has been tested here namely the cottonseed raw oil, the cottonseed methyl ester, the soybean raw oil, the soybean methyl ester and the diesel fuel as a reference fuel.

In this paper, a nonlinear semi-active vehicle suspension system using MR fluid dampers is investigated to enhance ride comfort and vehicle stability. Fuzzy logic and fuzzy self-tuning PID control techniques are applied as system controllers to compute desired front and rear damping forces in conjunction with a Signum function method damper controller to assess force track-ability of system controllers. The suggested fuzzy self-tuning PID operates fuzzy system as a PID gains tuner to mitigate the vehicle vibration levels and achieve excellent performance related to ride comfort and vehicle stability. The equations of motion of four-degrees-of-freedom semi-active half-vehicle suspension system incorporating MR dampers are derived and simulated using Matlab/Simulink software.

Nonparametric models do not require any assumptions on the underlying input/output relationship of the system being modeled so that they are highly useful for studying and modeling the nonlinear behaviour of Magnetorheological (MR) fluid dampers. However, the application of these models in semi-active suspension is very rare and most theoretical works available on this topic address the application of parametric models (e.g. Modified Bouc-Wen model). In this paper, a nonparametric MR damper model based on the Restoring Force Surface technique is applied in vehicle semi-active suspension system. It consists of a three dimensional interpolation using Chebyshev orthogonal polynomial functions to simulate the MR damper force as a function of the displacement, velocity and input voltage. Also, a damper controller based on a Signum function method is proposed, for the first time, for use in conjunction with the system controller of a semi-active vehicle suspension.

In this paper, the performance tradeoffs in the design of electronically controlled suspension systems are theoretically studied. Using quarter car model, a new treatment procedure for the control laws is introduced using fully active suspension system with two control strategies. The first strategy is considered for vehicle vibration isolation due to random road excitation only. The second strategy is considered to perform a zero steady-state suspension deflection due to body vehicle attitude variation during maneuvering, braking and aerodynamics as well as vibration isolation due to random road excitation. The two strategies are achieved by using two different optimization techniques combined with PID (Proportional-Integral-Derivative) compensator. The first technique is based on Linear Quadratic Regulation (LQR) technique and the second technique is based on Genetic Algorithm (GA).

The dynamics of vehicles became one of the most important aspects for current developments of electronically controlled steering, suspension and traction/braking systems. However, most of the published research on vehicle maneuverability doesn't take into account the effect of the dynamic tire load and its variation on uneven roads. Clearly, it was stated that using a suitable active suspension system could reduce this dynamic tire load. This dynamic tire load is playing a vital role as it is the major link between the vertical and lateral forces exerted on the road, which affects the lateral dynamics of the vehicle. In this paper, a practical hydro-pneumatic limited bandwidth active suspension system with and without wheelbase preview control is used to study its influence on the vehicle stability in lateral direction. The model is a longitudinal half car with four degrees of freedom.

The transformation of rapeseed oil into methyl ester through the transestrification process normally produce biodiesel fuel with kinematic viscosity almost double that of the commercial diesel fuel. The bulk modulus of biodiesel is also higher than that for the conventional diesel fuel. In this paper, the effects of the two physical properties on the injection characteristics of Rapeseed Methyl Ester (RME) are discussed. The injection characteristics considered here were namely; nozzle chamber pressure, needle lift, and fuel injection rate. The mutual effects of engine speed and delivery pipe length were also analyzed. A previously developed computer model was used to simulate the injection process of the conventional pump-line-nozzle injection system. An explicit finite difference scheme was adopted to solve the unsteady flow equation within the delivery pipe.

Plug-in hybrid vehicles connect to the power grid while parked so they can operate on electricity from the grid as well as on petroleum-based fuel. This distinguishes them in a fundamental way from the plug-less hybrid vehicles currently produced or planned by auto-marker which rely 100% on the petroleum-based fuel. A plug-in hybrid can reduce emissions. However, the aim of this paper is to investigate experimentally the aerodynamic noise performance of a plug-in hybrid vehicle induction motor with the view of evaluation. For this reason, a special test rig was developed to simulate the motor aerodynamic noise source. The results indicate that significant information can be obtained for this source. This can be an effective way to control this generated noise and consequently reduce the vehicle interior and exterior noises and look promising.

In this work the effects of vehicle vertical vibrations on the tires/road cornering forces, and then consequently on vehicle lateral dynamics are studied. This is achieved through a ride model and a handling model linked together by a non-linear tire model. The ride model is a half vehicle with four degrees of freedom (bounce and pitch motions for vehicle body and two bounce motions for the two axles). The front and rear suspension are a hydro-pneumatic slow-active systems with 6 Hz cut-off frequency designed based on linear optimal control theory. Vehicle lateral dynamics is modeled as two degrees (yaw and lateral motions) incorporating a driver model. An optimal rear wheel steering control in addition to the front steering is considered in the vehicle model to represent a Four Wheel Steering (4WS) system. The tire non-linearity is represented by the Magic Formula tire model.

Vehicle suspension along with tires and steering linkages is designed for safe vehicle control and to be free of irritating vibrations. Therefore the suspension system designs are a compromise between ride softness and handing ability. However, this work is concerned with a theoretical investigation into the ride behavior of actively suspended vehicles. It is based on using fuzzy logic control (FLC) to implement a new sort of active suspension system. Comparisons between the behavior of active suspension system with FLC with those obtained from active systems with linear control theory (LQR), ideal skyhook system and the conventional passive suspension systems. Results are introduced in such a way to predict the benefits that could be achieved from fuzzy logic system over other competing systems. Furthermore, a controller is designed and made by using results of FLC system, theoretical inputs are used to examine the validity of this controller.

Squeal from brakes is a problem in the automotive industry and large efforts are made to understand the squeal tendencies. The approach taken is mainly to change the design of the caliper, fine-tune the brake pad material and finally to trim the introducing shims on the backside of the pads. Despite these efforts still no general solutions exist. To advance the situation, a deeper understanding of the actual source of excitation of the sound in the friction interface is needed. However, in the present investigation the surfaces modifications of brake disc and pad have been tested with respect to the understanding properties. The surfaces modifications are slotted pad material and coated disc. All tests have been made in a brake test stand consisting of a complete front wheel corner of a vehicle. The changes have resulted in a significant understand of the generated noise.

In this paper, a hybrid roll control system, including passive and active roll control units, is designed to improve the roll dynamics of tanker vehicles and to reduce the lateral shifts of the liquid cargo due to lateral accelerations. The passive control system consists of radial partitions installed inside the vehicle container. These partitions rotate in phase with the liquid cargo as one unit about the longitudinal axis of the container in response to the induced momentum forces due to the lateral acceleration excitation. Torsion dampers are fixed between the partitions and the container's front and rear walls to reduce the oscillating motion of the liquid cargo. While the passive partition dampers control the dynamics of the liquid cargo inside the container, the dampers of the vehicle suspension are switchable, generating anti-roll damping moments based on the lateral acceleration level and the container filling ratio.

During the last few decades, fibrous composite materials have been diversified and replaced some traditional metallic materials. These materials provide high strength to weight ratio together with high environmental corrosion resistance. One of the basic engineering applications, which have been attracted by the properties of these composites, is the automotive engineering. In this paper, the authors manipulated the composite C-compression springs as a new trend of vehicle suspension system instead of coil or leaf springs. This type of springs can be safely and efficiently implemented in the vehicles' suspension systems and most probably be used in the new suspension design proposed earlier by one of the authors. Previous work on this context had shown a quality nature and economical technology in the use of composite springs in transportation and/or industrial applications.

In this paper, the Kalman filter algorithm is used to design a practical adaptive control strategy. The adaptation is intended to adjust the system operation according to the changes of road input. A moderate adaptive time of at least 3 seconds is used. Limit stops are added to prevent the increase in the wheel travel behind the specified limit. The active suspension feedback system is designed based on measuring only the suspension displacement. A gain scheduling adaptive scheme which consists of four sets of state feedback gains is designed. The estimation process of dynamic tyre deflection and other necessary state variables through the Kalman filter is illustrated. Among other things, this estimate is used to derive the gain scheduling adaptive scheme. The strategy is applied to a quarter car active suspension system. Results are generated at a constant speed on random road profiles.

E-spring is a recent innovation in vehicle suspension springs. Its behavior and characteristics are investigated experimentally and verified numerically. The mechanical and frequency-response-based properties of E-springs are investigated experimentally at both of the structural and constitutional levels. Thermoplastic-based and thermoset-based fibrous composite structures of the E-springs are modified at micro-scale with various additives and consequently they are compared. The experimental results reveal that additives of micrometer-sized particles of mineral clay to an ISO-phthalic polyester resin of the composite E-spring can demonstrate distinguished characteristics. A hybrid approach of the inter-laminar shear stress and Tsai-Wu criteria is implemented in order to identify failure indices numerically at the utmost level of loading and verify the experimental results.

Many basic studies were conducted to discover the main reason for squeal occurrence in both disc and drum brake systems. As, it is well-known that the squealed brake system is more effective than the non-squealed brake system and it is also a common discomfort. So, cancellation of the squeal is not preferable, however, elimination of the brake squeal is a favorable. An approach to study the drum brake squeal is presented based mainly on the Finite Element Method (FEM) representation. The brake system model is based also on the model information extracted from finite element models for individual brake components. This finite element method (FEM) was used to predict the mode shape and natural frequency of the brake system after appropriate verification of FEM.

Squeal of disc brakes is considered as a main source of discomfort for passengers. Typically 1 to 4 kHz noise is considered low frequency squeal and ≻8 kHz noise is considered high frequency squeal. It is a significant problem in passenger vehicles for the comfort of the passengers and a significant financial problem for industry too. Many manufacturers of brake pad materials spend up to fifty percent of their engineering budgets on noise, vibration and harshness (NVH) issues. Squeal noise is strongly correlated to the squeal index and degree of instability of the brake system assembly. Decreasing this squeal noise to some extent during braking is very important matter for the comfort of passengers. So, a mathematical prediction model of 10-degree-of-freedom has been developed to study the effect of different brake components parameters on the degree of instability and squeal index of the brake system.

A full vehicle of a preview control semi-active suspension system based on an interval type-2 fuzzy controller design using a magnetorheological (MR) damper to improve ride comfort is investigated in this paper. It is integrated with the force distribution system to obtain the optimal rate of road adhesion during braking and handling. The nonlinear suspension model is derived by considering vertical, pitch, and roll motions. The preview interval type-2 fuzzy technique is designed as a system controller, and it is attached with a Signum function method as a damper controller to turn on the voltage for the MR damper. This voltage is adjusted for each wheel based on the external excitation generated by road roughness in order to enhance ride comfort. To describe the effectiveness and adaptable responses of the preview controlled semi-active system, the performance is compared with both the passive and MR passive suspension systems during time and frequency domains.

The previous research work on Active Independent Front Steering (AIFS) system concluded an enhanced vehicle response and tire adhesion utilization. Some research emphasizes the importance of Tire Work load (TWL) in the generation of maximum possible tire forces that ensures vehicle controllability and stability. In this study, a mathematical model is constructed to investigate the effect of TWL as a parameter on AIFS performance. Toward such a target, a new Fuzzy control strategy is developed based on TWL and vehicle yaw rate as control inputs for the AIFS controller. Unfortunately, the TWL is not a measurable parameter or even easy to be estimated. Consequently, another control strategy was implemented based on slip angle and vehicle yaw rate as inputs for the AIFS controller.

This research aims to model and assess autonomous vehicle controller while including a four-wheel steering and longitudinal speed control. Such a modeling process simulates human driver behavior with consideration of real vehicle dynamics’ characteristics during standard maneuvers. However, a four-wheel steering control improves vehicle stability and maneuverability as well. A three-degree of freedom bicycle model, lateral deviation, yaw angle, and longitudinal speed is constructed to describe vehicle dynamics’ behavior. Moreover, a comprehensive traction model is implemented which includes an engine, automatic transmission, and non-linear magic formula tire model for simulation of vehicle longitudinal dynamics. A combination of proportional integral derivative (PID) longitudinal controller and fuzzy lateral controller are implemented simultaneously to track the desired vehicle path while minimizing lateral deviation and yaw angle errors.