Continuous developments in automotive technology brought about the reality of having an increasing number of autonomous vehicles (AV) on roadways soon. However, this advancement comes with the uncertainty of how the interaction between the autonomous and non-autonomous (non-AV) vehicles will play out. Using traffic simulators to model both AVs and non-AVs, and studying the effect of AVs on roadway

The objective in present study is to develop a regression analysis model to estimate real-world CO2 emissions of light-duty diesel vehicles considering domestic road conditions. For regression analysis variables, OBD data such as vehicle speed, acceleration, engine speed (rpm), and engine power were used. Regression analysis results were compared with CO2 emissions measured using PEMS on the test routes

Based on an analysis of the driving demand and system dynamics of heavy-duty vehicles equipped with electromechanical transmission (EMT), a double Markov model is put forward to represent drivers’ power demand for driving and electricity. Transfer probability matrices are calculated by utilizing the maximum likelihood estimation method. A power distribution control strategy based on stochastic dynamic

The process of obtaining durability test conditions of bus components is complicated. A way to build components durability test conditions based on driving cycle is proposed. Pure electric urban bus driving cycle in Xi’an based on running data is constructed based on combined clustering and Markov chain method, and simulation model of pure electric urban bus is built. The load conditions of the motor

The morphology and nanostructure of carbon and glass fiber are investigated by using XRD, SEM and TEM analysis. The composites are divided into three groups which consists of “without post-curing”, “post-cured at 80 °C for 6 hrs” and “post-cured at 120 °C for 3 hrs” to investigate curing temperature effect. The mechanical properties of composites are tested in the indentation, tensile, and flexural

In this paper, the cross coupling effect of the vibration paths in a dummy vehicle is investigated by the conventional transfer path analysis (TPA), the operational path analysis with eXogeneous inputs (OPAX) and the operational transfer path analysis (OTPA). The traditional transfer path analysis (TPA) is developed in the beginning of the 1980s at first. It is widely used as a tool for not only NVH

Modern diesel engines are struggling to enhance the power density. This is usually realized by being equipped with a turbocharger, which demands higher performances on exhaust flow and exhaust waste energy recovery (WER). In the present study, we investigated the variations of exhaust flow and exhaust energy recovery performance with different geometrical parameters of exhaust system and proposed an

High-cycle fatigue testing under different stress conditions must be performed in fatigue test methodology, and this requires expenditure both of money and time. The high-cycle fatigue test methodology also has the limitation of being a statistical approach to assessing estimated life that is not based on material properties. Thus to evaluate the estimated life of structural materials in transmissions

This study is to develop the linear regression model for estimating and predicting the HIC15, chest deflection and 3 ms chest g’s of driver and passenger dummy. Frontal impact test results of 28 vehicles from the MY2019 ∼ MY2020 USNCAP are utilized to construct the linear regression model. The average accelerations of vehicle, dummy head and chest are handled as the main variables. The fundamental

Plateau honing is used as a surface finishing and texturing process to reduce the friction between the piston and the cylinder bore in internal combustion engines. However, according to some studies, honing has detrimental side effects such as friction increase and the unintentional production of defects in the cylinder liner surface. This paper investigates the performance and side effects of the

In the automotive industry, short fiber reinforced plastic (SFRP) composites are important alternatives to metallic materials to improve fuel efficiency and reduce environmental problems. Vehicle components have geometrical discontinuities such as holes and weld lines subject to stress under cyclic loading. In this study, the fatigue behavior of SFRP composites was analyzed to explore the notch effect

The paper deals with the design of a system for changing the adhesion conditions in a road vehicle. The change in adhesive force is done by changing the radial reaction which the vehicle wheel transmits to the road. The paper describes a new device (SkidSystem) and its construction. The main element of the device is done in the form of a supporting frame; four supporting wheels are attached to this

In recent years, flat wipers are gradually adopted in the industry of transportation due to the rather simple structure than the standard wiper. A procedure is developed to evaluate the appropriateness of the geometry of a metallic flexor, one of major components of the flat wiper, in this study. The flexor is compressed against a level surface and the corresponding pressure distribution under the

With the increasingly strict emission regulations, the combustion noise has become an important factor restricting diesel engine development. Therefore, it is necessary to study the transfer function and prediction of combustion noise and to control it from the design stage. This paper proposes a method to calculate the combustion noise transfer function. An electronically controlled common rail diesel

This paper proposes a discrete-time preview-feedback controller capable of reducing nitrogen oxide (NOx) emissions with affordably low ammonia (NH3) slip downstream of a catalyst for selective catalytic reduction (SCR) systems. Because of the high NOx reduction rate, SCR systems are increasingly adopted in diesel engines. However, slow dynamics of the SCR system along with a time delay in the sensor

This research presents a multi-vehicle control strategy combining the merging control and platoon control to deal with the merging scenario in the freeway ramp entrance. In the merging controller, a selection algorithm is presented firstly to determine the merging sequence based on the initial states of the vehicles in the cooperative area. Subsequently, the optimized longitudinal trajectory of the

Rubber mount is a type of vibration isolator that can absorb vibration and minimize external disturbance. This study proposes an optimization method to design the geometry of a rubber mount to achieve particular stiffness values in two different loading directions. The proposed objective function of the geometry optimization problem is to minimize the error ratios between calculated and target stiffness

Path following control of the automatic guided vehicle (AGV) for material handling in the plant requires a smooth and high-precision continuous attitude adjustment. However, there are many difficulties in designing the controller, such as actuator saturation, parameter selection, and the influence of deviations relations. In this paper, an improved model predictive control SCMPC-ST with a state classification

Hot-stamped parts in a fully martensitic state exhibit very low ductility levels prior to failure, which limits their use in certain components. In the case of B-pillars, which may undergo impact loading, it could be desirable to create part zones with softer and more ductile microstructures. Local softening by means of an induction heating system is one of the methods of tailoring the properties for

Load path as a new analysis tool has been widely used in structural design and assessment of load-bearing performance, but it still lacks effective guidance for structural improvement. In this paper, a new structural improvement method of vehicle component based on the load path and load distribution analysis is proposed. Firstly, according to the structural function and design requirements, the potential

Semi-active suspensions have much better performance than the passive suspensions along with the advantages such as low power consumption and cost. In order to control the semi-active suspension system, such as MR damper, sensory feedback is required. The skyhook control which is the most widely used algorithm admits the velocity of damper and vertical sprung mass. For this, additional attachment,

In order to be acceptable to drivers, the adaptive cruise control (ACC) systems need to be designed based on the analysis of human driver driving behavior. A new safe distance model is proposed in this paper based on the analysis of real-world driving test data. The goal of the control algorithm is to achieve naturalistic behavior of the vehicle that can comprehensively address the issue of driving

With the reduction of vehicle interior noise, the Buzz, Squeak and Rattle (BSR) noises have become an intractable problem that needs to be tackled urgently. Seat system rattle noises have a large contribution to the passengers’ complaints, due to the close distance between the passengers and seats. The seat structure and its components can be sources of rattle noise based on their physical characteristics

To better understand the formation and evolution processes of soot, the two-color laser induced incandescence diagnostic method was applied on a single cylinder optical direct injection spark ignition engine. Soot volume fraction was measured, and soot distribution was imaged as cyclic fuel quantity changes. The results show that 45.5 mg/cycle generates the most soot at the same measure plane. Pool

The aim of this study was to elaborate on the methods of constructing combined components of a car mirror. The components were made of materials with different thermal expansion coefficient. The basis for the research were numerical simulations prepared in Moldex 3D software. The external cover of a mirror would be made of carbon composite based on epoxy resin (hereafter referred to as carbon), and

The ability to predict the intent of drivers from surrounding vehicles to change lanes is key to risk assessment and early danger warning systems. Since lane change trajectories are highly nonlinear, many studies have been performed on various machine learning algorithms using different features to predict a driver’s intent to change lanes. However, these algorithms use various features that cannot

The flow stability induced by the impingement of gas jets exiting from the intake manifold affects the in-cylinder flow characteristics of internal combustion engine. Using high-speed planar particle image velocimetry (PIV) with proper orthogonal decomposition (POD) analysis, an investigation was conducted to reveal the spatio-temporal characteristics of annular gas jets impinging in a region between

An anti-lock braking system (ABS) is an anti-skid braking system commonly used as a safety feature in vehicles. The hydraulic control unit for the ABS of a vehicle includes a plunger pump between the wheel and master cylinder. This paper presents numerical investigations of the effect of valve shapes on the performance improvement provided by a plunger pump, focusing on two different valve shapes,

An experimental system was developed to evaluate the fuel injection parts of a gasoline direct injection engine. An AC motor and an inverter were used to rotate the camshaft in the engine cylinder head. A single plunger high-pressure fuel pump (HPFP) driven by a square cam at the end of the camshaft was used in the gasoline direct injection engine. The rotation position of the square cam was measured

Electric vehicles are effective way to solve energy and environmental problems, but the promotion and application of electric vehicles are suppressed by their limited endurance range seriously. The regenerative braking technology is an important method to increase the endurance range of the electric vehicle. During the braking process, the kinetic energy of the electric vehicle can be converted into

In this paper, a vehicle localization fail safe process is proposed for improving localization reliability for level 3 autonomous driving. This process does not necessitate additional and expensive sensor configuration using sensor fusion with practical usage and high density maps for localization fail safe. The proposed process also suggests a three-step safety mechanism. The first step is to detect

The state of charge (SOC) is one of the important performance indicators of battery, which provides an important basis for the management and control of Battery Management System (BMS). In view of the characteristics of lithium iron phosphate battery, considering the model accuracy and calculation amount, the equivalent circuit model of improved PNGV was selected. Based on that, an improved Extended

Aerodynamic performance of a road vehicle has significant impact on energy efficiency, especially at high speed. Finding all possible ways to reduce aerodynamic drag has paramount importance on the development process of the vehicle. The study is conducted with an intention to contribute for driving range extension of an electric vehicle by the improvement of aerodynamic performance. In this study

Heavy vehicles service brakes are subject to severe loading conditions that can exceed the design conditions of safe operating performance in critical situations. Materials are prone to lose their design properties at high temperatures. Since the function of brakes is to convert the vehicle kinetic energy into heat by friction, temperature is the main variable to be considered, due to the fade of the

This study investigates the compressible-brake-fluid flow characteristics within an electric parking brake (EPB) caliper during the bleeding cycles, subsequently determines the fundamental cause for reduction in brake-bleeding performance, and suggests a new design for its improvements. Three-dimensional simulation validation of the brake-fluid consumption curve is conducted through the parameter study

In order to improve shift characteristics of an automatic transmission (AT), it is necessary to control and optimize the hydraulic pressure profile of a clutch. More than 8 speed ATs have been developed recently; thus, considerable time and human resource are required to calibrate the parameters. Herein, we propose a model-based automatic calibration method of clutch hydraulic pressure for an AT. The

In recent years, acausal modeling languages such as Modelica and VHDL-AMS have been used for model-based development. In this research, a cycle simulation model using an acausal modeling language for predicting the emissions of an internal combustion engine was developed for application to a vehicle simulation model for energy and emissions analysis. In order to develop simulation models with higher

If deceleration is constant in a vehicle crash, deformation of the vehicle is a function of impact speed and impact duration. The ratio of actual deformation to this idealized quantity may be used to summarize the shape and effects of the deceleration pulse. This ratio reflects whether the pulse is front-loaded (acceleration is greater early in the pulse than later), or back-loaded (acceleration is

Self-driving safety is one of the major concerns raised with regard to pushing the use of automated vehicles on roads. Fully automated vehicles are forced to make appropriate decisions in an uncertain environment where driverless and human-driven vehicles share the road together. This study proposes a new model that can be used to enhance the autonomous driving behavior at a non-signalized intersection

To enhance the calibration efficiency, reduce the fuel consumption and improve the emission performance of the engine, a calibration method using Gaussian Process Regression (GPR) is proposed in this work. First, the design of experiment (DoE) is constructed by using the Space-filling method, and the engine bench sampling test is implemented according to results of DoE. Then, the square exponential

This study investigates effects of a novel GDI injector outer tip design on the airflow behavior, spray formation, injector deposits and engine particulate emissions. The novel design has turbine-like blades that are located on the tip of the injector. The effects of turbine-like blades on the airflow behavior below the injector tip is initially investigated by means of numerical simulations with three

Fuel injection stability of high-pressure common rail fuel injection system (HPCRFIS) under multiple injection modes is a recognized technical problem. To explain it essentially, a numerical model based on bond graph method, which provides a standardized series of symbol system to describe various components in different physical fields as well as interactive effect analysis tool for different energy

In this paper, an emergency collision avoidance system is proposed by including not only braking but also steering control actions. The minimum distance to avoid collision is calculated separately for braking and steering based on the relative motion to the surrounding vehicles and the lane information obtained through the vision sensor. For steering avoidance control, an optimal control input is calculated

Every land moving object accelerates or decelerates based on the fictional coefficient of the road surface. It has been known that this coefficient on the road is determined by the type of road surface. In this work, we propose a simplistic, machine-learning based solution to estimate the road type using the reflected ultrasonic signals paired with ultrasonic transmitter and receiver. Since the reflected

This paper analyses changes in body geometry and related wheel geometry which may affect the wear of passenger car tyres. By means of an electronic device, changes were measured in the position of the spots that best reflect the changes of the body geometry. This included the front bench attachment, front suspension and rear suspension, at the beginning of the front stringers, at the end of the rear

Path tracking is an essential aspect of the navigational process of self-driving cars. Especially, accurate path tracking is important for not only normal urban roads but also narrow and complex roads such as parking lot and alleyway. The pure pursuit method is one of the geometric path-tracking methods. Using this method, the look-ahead point can be selected far away and the control input is computed

This study aims to determine the structural parameters of the equivalent vertical stiffness design of a modular deformable wheel. A gas stiffness model in the air cavity of the modular deformable wheel is established on the basis of the wheel’s structure and the ideal gas equation. Then, the change curve of the radial stiffness of the modular deformable wheel is obtained, and the design model of the

Inferring driver workload has started to draw greater attention with the emerging automotive technology of higher autonomy. In this paper, we revisited the popular assumption of fixed workload levels determined by the driving environment, and propose a framework to generate a Personalized Driver Workload Profile (PDWP) that incorporates individual differences. A rich set of physiological and operational

To improve the economic and comfort performance of pure electric vehicles (PEV), this paper proposes a novel H-infinity gear-shifting controller for dual-speed Transmissions (DST) to achieve a smooth and swift shifting when considering uncertain disturbances in system. Firstly, the structure as well as the working principle of the DST for PEV are introduced briefly and the mathematical model of the

Recently, the driving performance that maximizes driving pleasure, exhaust sound quality, and quietness have been recognized as important elements according to the demands of clients. Technology has been dramatically developed while the evaluation and improvement of the exhaust system have been attempted using various methods to meet the requirements of clients, the largest problem in designing the

Most tire properties are closely related to the pattern deformation. In order to explore the relationship between tire performance and defined deformation parameters in the contact area between the pneumatic tire and road surface, ten types of 205/55R16 passenger car radial (PCR) tires were selected as the research objects. Using VIC-3D non-contact strain measurement system and by subdividing the contact

Driver distraction is an important contributing factor to increase crash risks. The effect of secondary task engagement may vary by interaction types and driver age. Thus, it is essential to understand the impacts of distraction type and age on driving performance for improving the safety of in-vehicle secondary task design. This paper aims to assess potential risks induced by visual and auditory secondary

In order to study the effect of front and rear anti-roll bar’s stiffness on vehicle’s handling stability, the structure and force of the anti-roll bar are analysed, and the vehicle’s rolling model, simplified car motion model and multi-body dynamics model of a car are established. The influence of stiffness change of the anti-roll bar on understeer of the vehicle is studied by constant radius cornering

This paper is about test procedure development of a 4 year project regarding V2X based cooperative safety systems. The project was the first major cooperative safety research project which was led by automotive industry side in Korea. The paper includes a brief introduction of the overall project, basic warning logics, detail test procedures, and some part of test results. The scope of the project

Recently, as vehicles are getting more intelligent, interest in improving vehicle ride comfort has been increasing. Appropriate control of a clutch in the vehicle powertrain can play a major role in improving the vehicle ride comfort. Previously, many researches on tracking controllers of clutch slip speed and clutch transmitted torque in clutch slip engagement control have been conducted. However

The increasingly stringent emission limits require high performances also at high mileage, increasing the need for reliable catalysts characterization during their whole useful life. Thermal ageing is the main problem: high temperatures, variable environment and the presence of water lead to a progressive deactivation of the components. Due to the cost of ageing a converter on-road or on an engine

The main objective of this thesis is to propose a method to overcome a limitation of combustion in lean-burn condition by applying the Amplified Ignition Source (AIS). In order to analyze the combustion efficiency, Constant volume combustion chamber (CVCC) was designed to conduct experiments such as flame visualization, combustion pressure and flame kernel. As the experimental and analysis conditions

In this study, noises generated when opening the rear door of a vehicle are identified, which has recently been receiving renewed attention in the automotive industry. To confirm the characteristics of door opening noise, the noise and vibrations in a rear quarter panel and a rear outer door panel were measured experimentally. Furthermore, the modal testing on these panels was conducted such that the

Longitudinal vortex formed at the rear area of the vehicle is one of the main sources of vehicle aerodynamic drag. The boat tail shape is applied to reduce the longitudinal vortex strength of the SUV so that the aerodynamic drag is improved. For this study, a commercially available SUV produced by domestic automobile company, Hyundai Motor Company, is selected as a baseline model. The boat tail shape

In this paper a throw distance model for vehicle-cyclist collisions is presented, based on a deterministic approach with a cyclist mass point representation. Vehicle-cyclist collisions are characterized by three distinct impacts, which determine the entirety of the cyclist’s kinematics, also throw distance implicitly. Cyclist kinematics are analyzed by breaking down the motion into multiple phases