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

As emissions regulations are tightened, various engine and emission reduction improvements have been applied. The reduction of particulate matter (PM), a major diesel engine emission, relies solely on after-treatment in the diesel particulate filter (DPF). It is not possible to satisfy current exhaust regulations without a DPF installed downstream of a diesel engine. Therefore, in the design of DPF

In this study, the discrete adjoint approach with the grid deformation technique based on radial basis function was presented to solve the tough problem that the complex shape of the defrosting duct is very difficult to be optimized with multiple parameters in the improvement of the defrosting performance of vehicle. Firstly, the defrosting performance of a light truck was analyzed. Then the discrete

Recently, governments around the world are seeking to reduce pedestrian mortality by strengthening pedestrian safety regulations such as Euro-NCAP (European New Car Assessment Program). In 2015, the Euro-NCAP revised the upper leg assessment for the upper legform to WAD (Wrap Around Distance) 775 mm test. The methods and procedures of the revised upper legform to WAD 775 mm test are analyzed and evaluated

To investigate the temperature fields of piston set-liner under the friction heat of ring pack, it is established a friction heat allocation model of ring pack based on the heat transfer theory of semi-infinite body. In this model, the piston ring, lubrication film and liner are treated as a three-layer medium. Furthermore, the distribution model of ring pack friction heat, the unsteady heat-mixed

Developments in vehicle technology and accompanying improvements in NVH performance have led to increased consumer demand for high sound quality, such as a “sporty” engine sound. As sporty sound is subjective, this study sought to express its meaning quantitatively and to develop a model that accommodates the differences in individuals’ tastes. Engine sounds of four vehicles at wide-open throttle were

This paper investigates the oxidation kinetics of carbon black on acicular mullite using thermogravimetric (TGA) and mullite microstructures by scanning electron microscopy (SEM) for the development of diesel particulate filters (DPFs). It is observed that the amount of each chemical composition strongly affects the structure of mullite. The addition of AlF3 and V2O5 to mullite promotes the growth

One of the most important requirements of the Formula SAE (Society of Automotive Engineers) race car design competition is that the car structure must guarantee a high protection level in case of frontal impacts, by preventing intrusions into the driver foot zone or dangerous deceleration levels. These functions are mainly performed by the impact attenuators, which have to guarantee a high specific

Due to the nonlinear behavior of rubber for bushings, the prediction of mechanical properties of the bushing requires nonlinear finite element analysis (FEA) techniques and a lot of computation time. Therefore, we propose a method to efficiently predict the stiffness of bushings using an Artificial Neural Network (ANN) model trained by data from FEA. First, FEA was performed for the designed 3D and

This study presents an adaptive dual closed-loop speed control strategy for the natural gas engine used in a range extender to improve the robustness against parameter uncertainties, unmodeled dynamics and unknown disturbance. Compared to existing methods, this strategy takes into account the influence of the throttle valve dynamics on the intake airflow in the design of the inner-loop intake pressure

As one of the most common engine types in nowadays, the thermal efficiency of spark-Ignition (SI) engine is limited due to the lower compression ratio. Various technical solutions have been proposed to suppress knock and improve compression ratio of SI engines. In this paper, an new technical solution based on electromagnetic valve train (EMVT) was proposed to suppress knock of spark ignition engines

TTEthernet is a new high availability network protocol for the automotive domain, providing support for the transmissions of time-critical periodic frames in a time-triggered (TT) traffic and event-triggered frames in a rate-constrained (RC) or best-effort (BE) traffic. The design of a system scheduling with communication over the TTEthernet is not an easy task because of protocol and timing constraints

In this study, the drag torque was predicted considering the uncertainties in geometry and material properties of automotive wheel bearing seals. For this, the deformation of the seals was firstly analyzed using numerical analysis based on the finite element method. Three types of experiments for material properties of rubber were conducted to improve the reliability of deformation analysis for the

This paper investigates the internal shape correctness of alternator stators occurring in high and low temperature storage tests. This kind of failure can affect the adequate operation of alternators since vibrations can occur during rotation of the other part of the alternator, the rotor. This error can reduce the efficiency of the alternator. The aim of this study is to examine the influence of different

As a key component of the engine, piston have to work in harsh environment for a very long time, its friction performance and operational reliability have been the research focus. In this paper, a four-cylinder diesel engine was used as the research object. The dynamic model considering multi-factors such as inertial parameters, surface roughness, thermal deformation and elastic deformation was established

Light electric vehicles (LEVs) are usually used as neighborhood electric vehicles (NEVs) for the second vehicle or car-sharing service. For LEVs, it is important to reduce energy consumption to have greater mileage at the same battery capacity. One of the direct ways to decrease energy consumption is the efficiency improvement of the traction motor, which is the main propulsion system. Also, the weight

The removal of nitrogen oxides (NOx), which are major atmospheric pollutants, in exhaust gas after-treatment systems, has been studied extensively. The catalytic reduction of NOx in lean-burn environments is challenging in diesel after-treatment technology. The most relevant catalytic NOx reduction technologies for diesel engines are summarized in this review paper, focusing on current catalytic after-treatment

Wireless power transfer technology is essential for autonomous electric vehicles. Electric vehicles demand increasingly higher power outputs. Therefore, it is necessary to study the harmfulness of human body exposure to electromagnetic waves generated in a wireless power transfer system. This study provides exposure assessment for a 20-kW wireless power transfer for electric vehicles. The electromagnetic

The assessment of vehicle dynamic comfort to human body vibration varies from person to person. Even though the dynamic comfort rating can be obtained by placing measurement devices over the cabin, passengers may have dissimilar sensations. For many car manufacturers, both subject and objective measurements are used together at development of new cars. To effectively assess the dynamic comfort of vehicle

The electronic stability control (ESC) system is a computerized technology that improves vehicle stability by detecting and reducing the loss of traction. The hydraulic control unit for an anti-lock braking system (ABS) or an ESC system in a car includes a hydraulic pump located between the wheel and master cylinder. The function of the hydraulic pump is to allow the brake fluid to return from the

This study examined the physical and chemical properties of engine oil with a submicron-sized carbon particle lubricant mixture. Spherical carbon particles were added to engine oil to lower the friction and wear losses. In the current study, morphological and chemical analyses of these carbon particles were performed using field emission scanning electron microscopy and energy dispersive spectroscopy

An electric vehicle (EV) powertrain is comprised of a motor and reduction gear. Thus, it must be designed by considering both components to improve its dynamic and economic performances. To obtain the optimal design of powertrain components for an EV, this study employs a two-stage analysis model focusing on the motor and vehicle at each stage for accuracy and efficiency. In the first stage, a motor

Topology optimization is a shape optimization method connected with finite element (FE) analysis, and has recently received increasing attention owing to rapid evolution of additive manufacturing (AM). In this study, an automotive knuckle part was developed by combining kinetic analysis, FE structural analysis, and topology optimization. A kinetic analysis based on a multibody dynamics simulation was

The abnormal noises, such as clunking and popping, are usually generated when the car turns or drives over bumps. It could happen frequently when the free gap (clearance) values in the axial direction of the lower control arm ball joint are higher than normal values. The spherical surface of the ball stud is commonly assumed to have been corroded by foreign substances such as water, and the rough surface

The mobility method is frequently used to analyze the performance of journal bearings subjected to dynamic loads in an internal combustion engine. As the mobility method generally assumes Newtonian fluid, the realistic approach for the multigrade lubricant in engine bearing lubrication is limited. The new mobility approach for non-Newtonian fluid is introduced in this study. A power-law model is applied

The working process of the high-speed solenoid valve (HSV) of high-pressure common rail (CR) injector has the characteristics of electro-magnetic-mechanical-hydrodynamic multi-physical field coupling. However, most of the research work in this field is carried out without considering hydrodynamic environment of the HSV. Furthermore, the dynamic response characteristics of the transient fuel hydrodynamic

FMVSS (Federal Motor Vehicle Safety Standard) 201, Standard on Occupant Protection in Interior Impact, requires that the FMH (Free Motion Headform) impact tests result in HIC(d) less than 1000. Especially in the early stage of a vehicle development it is very difficult to conduct the impact tests, so it is necessary to develop a numerical model by which HIC(d) can be predicted. A finite element model

Due to the gradual reinforcement of emission regulations, exhaust gas after-treatment systems have become more complicated, and various engine control algorithms have been applied to diesel engines. However, the misuse of advanced exhaust gas after-treatment systems could cause additional problems. For instance, diesel vehicles that use of a diesel particulate filter (DPF) generally require periodic

The Korean light tactical vehicle (KLTV) is a vehicle with enhanced mobility, versatility, and survivability, in comparison with conventional vehicles. The KLTV is classified as a special vehicle, so there is no standard to evaluate its passenger safety. Therefore, ECE R 66 (rollover test) and ECE R 29 (roof strength test) regulations are selected as criteria for evaluating the passenger safety during

At the conceptual design stage, thin-walled beams (TWBs) with the complex cross-sectional shapes are extensively used to compose the automobile frame. Thus, the performances of automobile frame are determined by cross-sectional shapes of TWBs. Currently, the modifications of complex cross-sectional shapes depend on the experience of engineers, which often causes the design risk. Meanwhile, to our knowledge

This study developed a control algorithm of torque vectoring system to improve the handling performance of a green-car and evaluate the performance of vehicle dynamics to improve the controllability and stability. Firstly, this study configured the control algorithm with the supervisory controller that decides the control mode by checking the current driving status of a vehicle, target yawrate calculator

In the used car market, mileage is one of the principal criteria used for evaluating the overall condition of a vehicle. For this reason, mileage fraud continues to occur. Futhermore, the number of malicious brokers who obtain a monetary advantage by manipulating vehicle mileage is increasing. As many used cars with manipulated mileage are sold each year, buyers have suffered significant monetary damages