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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.

1 Rear wheel drive vehicles have a long driveline using a propeller shaft with two universal joints. Consequently, in this design usage of universal joints within vehicle driveline is inevitable. However, the angularity of the driveshaft resulting from vertical oscillations of the rear axle causes many torsional and bending fluctuations of the driveline. Unfortunately, most of the previously published research work in this area assume the propeller inclination angle is constant under all operating conditions. As a matter of fact, this assumption is not accurate due to the vehicle body attitudes either in pitch or bounce motions. Where the vehicle vibration due to the suspension flexibility, either passive or active type, exists.

In order to achieve the high capability of the ride comfort and regulating the tire slip ratio, a preview of a nonlinear semi-active vibration control suspension system using a magnetorheological (MR) fluid damper is integrated with traction control in this paper. A controlled semi-active suspension system, which consists of the system controller and damper controller, was used to develop ride comfort, while the traction controller is utilized to reduce a generated slip between the vehicle speed and rotational rate of the tire. Both Fractional-Order Filtered Proportional-Integral-Derivative (P¯IλDμ) and Fuzzy Logic connected either series or parallel with P¯IλDμ are designed as various methodologies of a system controller to generate optimal tracking of the desired damping force. The signum function method is modified as a damper controller to calculate an applied input voltage to the MR damper coil based on both preview signals and the desired damping force tracking.

The latest developments in the engine’s design aim to maximize the power output, downsize the engine, and minimize the fuel consumption. This paper investigates the thermomechanical loads on the piston of a turbocharged diesel engine. The main emphasis is the effect of increasing the boosting pressure on the piston loading until the possible maximum engine power is achieved. Also, it proposes the modification of the piston design in order to increase the durability for more power loading and decrease the total mass. The temperature distribution on the piston body, the corresponding thermomechanical deformations, the stress distribution, and the safety factor is excessively calculated. Finite element methods (ANSYS workbench) is used to analyze the thermomechanical loads applied to a three-dimensional model. The study is applied to the piston of a 300 hp diesel engine (base case) in order to increase the engine power by 17% (upgraded one).

In this article, an experimental investigation on octane boosting was performed using a renewable material. A fully instrumented research spark-ignition engine, Ricardo E6/MS, was used to perform the experiments. This experimental work was achieved to reveal the effect of Jojoba bio-gasoline, as an octane booster, and its effect on basic gasoline specifications. Therefore different blends of basic gasoline (a mixture of reformate and isomerated gasoline) and Jojoba bio-gasoline were prepared. Also, the influences of using such blends on the performance and emissions at various operating conditions, as well as the engine knock and pre-ignition were intensively examined. The investigation revealed that boosted gasoline with a research octane number of 90, 92, and 95 can be obtained by blending basic gasoline with 13, 16, and 20.9% of Jojoba bio-gasoline, respectively.

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 the present article, the knock tendency and pre-ignition resistance (PIR) were determined experimentally for different blends of kerosene and jojoba bio-gasoline. The effects of varying equivalence ratios, rotational speed, inlet air temperature and pressure, and ignition timing on knock tendency and PIR were investigated. The influence of compression ratio on PIR was also studied. Jojoba bio-gasoline was synthesized using transesterification method through performing a chemical reaction between well-stirred jojoba raw oil and alcohol. Experiments were carried out on a Ricardo E6/MS variable compression ratio spark-ignition (SI) engine fuelled by jojoba bio-gasoline/kerosene blends of volumetric percentages of 0%, 5%, 10%, 15%, and 20% jojoba bio-gasoline. The onset of pre-ignition and knock were detected by observing the pressure oscillations using a piezoelectric pressure transducer, a synchronizing magnetic sensor, and a degree-marking probe.

The present work investigates the effect of magnetorheological fluid (MRF) on limited slip differential (LSD) system for automotive applications to improve torque distribution which influences traction and maneuverability. The proposed differential system uses a magnetorheological fluid which permits to control the locking torque effectively and then improve the vehicle traction characteristics. To evaluate the proposed system, a prototype model involves some rotating clutches submerged in MRF associated with an electromagnet coil was built. Experimental tests were carried out in two cases, first case by applying mechanical force on the friction clutches and the second by applying magnetic field to change the MRF viscosity. The yield stress of MRF depends on the magnetic field applied by the electromagnet by varying electric current. The controllable yield stress generates friction force on the rotating clutches surfaces to transmit torque.

Gear fault diagnosis is important in the vibration monitoring of any rotating machine. When a localized fault occurs in gears, the vibration signals always display non-stationary behavior. In early stage of gear failure, the gear mesh frequency (GMF) contains very little energy and is often overwhelmed by noise and higher-level macro-structural vibrations. An effective signal processing method would be necessary to remove such corrupting noise and interference. This paper presents the value of optimal wavelet function for early detection of faulty gear. The Envelope Detection (ED) and the Energy Operator are used for gear fault diagnosis as common techniques with and without the proposed optimal wavelet to verify the effectiveness of the optimal wavelet function. Kurtosis values are determined for the previous techniques as an indicator parameter for the ability of early gear fault detection. The comparative study is applied to real vibration signals.

The thermal performance of an ammonia-water-hydrogen absorption refrigeration system using the waste exhaust gases of an internal combustion diesel engine as energy source was investigated experimentally. An automotive engine was tested in a bench test dynamometer, with the absorption refrigeration system adapted to the exhaust pipe via a heat exchanger. The engine was tested for different torques (15 N.m, 30 N.m, and 45 N.m). The exhaust gas flow to the heat exchanger built on the generator was controlled manually using two control valves. The refrigerator reached a steady state temperature between 10 and 14.5°C about 3.5 hours after system start up, depending on engine load. The maximum coefficient of performance was 0.10 obtained for the controlled exhaust mass flow case at torque 30 Nm after 3hrs from system startup.

Recently, the control of traffic flow has been proposed using several types of criteria (e.g. minimum-time control, minimum fuel control and so on). Most recently, an environmental noise pollution problem caused by the road traffic is being aggravated more and more by the consolidation and expansion of roadway system particularly in urban areas. However, the objective of this paper is to control road traffic flow by regulating traffic noise propagation in an urban area in Cairo city. The results of traffic noise prediction obtained by trending of the experimental data collecting by systematic noise measurement and the evaluation of the traffic noise which is in close connection with physical parameters of traffic flow and noise propagation characteristics is presented. The analysis of road traffic flow noise control is based on the mixed integer non-linear programming technique, where the optimal control strategy is used.

In the design of recreational vehicle alternators, a particular challenge arises from marketing and engineering teams' desire to ensure that their products meet “best in class” sound quality characteristics. Furthermore, it is desirable to know these characteristics in measurable engineering terms in the product design stage, preferably before prototypes are built and tested. However, the aim of this paper is to investigate experimentally the electromagnetic sound quality characteristics of a vehicle alternator with the view of determination. For this reason, a special test rig was designed to simulate the alternator electromagnetic 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 improve the vehicle alternator sound quality and look promising.

Despite considerable advances in predictive maintenance concepts are still largely reserved for only the most critical system components and have not found their place in mainstream machinery health management. Even though there are a number of condition monitoring and analysis techniques, researchers are in search of a simple and easy way to monitoring the condition of an engine, which is an omnipresent and an important power unit in any vehicle or machinery. Vibrations have been the most recent easy to measure condition monitoring. However, this paper will provide the details of diagnostic technologies that can be applied on a single cylinder diesel engine components, and span a continuum of sophistication and rely upon the availability vibration measurement equipments. The vibration measurements are used as monitoring parameters, while single-processing indices are used for diagnosis procedure.

The number of speed humps (sleeping policemen) has seen a global increase in the last decade. This paper addresses the geometric requirements of these humps using Genetic Algorithms optimization techniques to control the speed, stability, and ride feel of the traversing vehicles. The interaction between road hump profile and the modeled vehicles (passenger and a two-axle truck) are studied with a dynamic model. The shape of the proposed profile is described by numbers of amplitudes of harmonic functions. The extreme acceleration of the drivers’ seats of the vehicles traversing the hump is set as multiobjective function for the optimization process, taking into consideration the road-holding ability represented by the tire lift-off speed. The results show that hump geometry can be improved while fulfilling the requirements of speed control and vehicle dynamic responses.

The DC power supply is ingredient part in the automotive industries as it has been used as a DC power supplies for a wide range of loads. Meanwhile, it is mandatory for battery charging. These types however, causes many problems such as poor power factor, high input current harmonics distortion and uncontrolled DC voltage. In this paper, an improved input power factor correction that uses a combined control system consists of two nested loops with a feedback of the DC voltage and input current as long as a feed forward from the output power. The system has been analyzed, modeled, simulated and experimentally verified. The novel feature of the proposed control scheme resides in fact that it is not only achieve nearly unity power factor with minimum input current total harmonics distortion only but it also introduce superior performance in DC voltage transient conditions.

All automotive fleets' ownerships want to increase their fleets' availability; therefore, they resort to consider the conventional maintenance policy. Despite of, this policy increases fleets availability but the cost will be high. This is due to replace the parts before the end of their lifetime. On the other hand, this policy is based on time where it is not cost-effective. Consequently, this conventional maintenance policy is not adequate to fulfill the needs of high availability for automotive fleets. However, in this paper the study is directed to condition-based predictive maintenance concept as an alternative policy to determine fleet's health for increasing the fleet availability and to reduce the operating cost. The concept is based on predicting the system degradation and calculating the reliability function for the component. An application carried out on internal combustion engine crankshaft main bearing to illustrate the effectiveness of this technique.

In this paper, a direct technique to estimate the rollover threshold limits of partially filled tank trucks is applied for banked roadways. Overturning and restoring moments are calculated as functions of tank shape, fill level, gradient of both liquid cargo free surface and the lateral inclination of banked road surfaces. The static rollover threshold of tanker trucks traveling on laterally banked roadways is estimated by balancing the net value of the total overturning moment against the net value of the restoring moment. Different filling ratios are considered for circular, elliptical and modified tank vehicles. The rollover threshold limits are calculated considering a superelevation range of (0.0-0.1) for the lateral road banking as defined by Blue and Kulakowski (1991). It is shown that the vehicle rollover threshold limit increases with an increase of the angle of the lateral road banking.

This paper is concerned with the analysis of the performance of actively suspended vehicles when the effects of the aerodynamics are considered. The investigation is wholly theoretical and treats a half vehicle model, active suspension, through simulation of running at different speeds on a random-profile road. Using classical control laws, which do not account for aerodynamic effects, it is shown that starting from a vehicle speed of 35 m/s, ride comfort and road holding parameters significantly deteriorate. A method is introduced to modify the control strategy so that these effects can be taken into consideration. Various forms of control laws are presented, and conclusions are drawn to specify the benefits that could be achieved from this modified control strategy.