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Electromagnetic valve (EMV) actuation system is a new technology for the improvement of fuel efficiency and the reduction of emissions in SI engines. It can provide more flexibility in valve event control compared to conventional variable valve actuation devices. However, a more powerful and efficient actuator design is needed for this technology to be applied in mass production engines. This paper presents the effects of design and operating parameters on the thermal, static and dynamic performances of the actuator. The finite element method (FEM) and computer simulation models are used in predicting the solenoid forces, dynamic characteristics and thermal characteristics of the actuator. Effect of design parameters and operating environment on the actuator performance were verified before making prototypes using the analytical models. To verify the accuracy of the simulation model, experimental study is also carried out on a prototype actuator.

As environmental problems such as global warming are emerging, regulations on automobile exhaust gas are strengthened and various exhaust gas reduction technologies are being developed in various countries in order to satisfy exhaust emission regulations. Exhaust gas recirculation (EGR) technology is a very effective way to reduce nitrogen oxides (NOx) at high combustion temperatures by using EGR coolers to lower the combustion temperature. This EGR cooler has been mass-produced in stainless steel, but it is expensive and heavy. Recently, high efficiency and compactness are required for the EGR cooler to meet the new emission regulation. If aluminum material is applied to the EGR cooler, heat transfer efficiency and light weight can be improved due to high heat transfer coefficient of aluminum compared to conventional stainless steel, but durability is insufficient. Therefore, the aluminum EGR cooler has been developed to enhance performance and durability.

CO2 emission is more serious in recent years and automobile manufacturers are interested in developing technologies to reduce CO2 emissions. Among various environmental-technologies, the use of solar roof as an electric energy source has been studied extensively. For example, in order to reduce the cabin ambient temperature, automotive manufacturers offer the option of mounting a solar cell on the roof of the vehicle [1]. In this paper, we introduce the semi-transparent solar cell mounted on a curved roof glass and we propose a solar energy management system to efficiently integrate the electricity generated from the solar roof into internal combustion engine (ICE) vehicles. In order to achieve a high efficiency solar system in different driving, we improve the usable power other than peak power of solar roof. Peak power or rated power is measured power (W) in standard test condition (@ 25°C, light intensity of 1000W/m2(=1Sun)).

This paper examines the effect of pulse-and-glide (PnG) driving strategies on the fuel efficiency when applied on parallel HEVs. Several PnG strategies are proposed, and these include the electrical, mechanical, and combined PnG strategies. The electrical PnG strategy denotes the hybrid powertrain control tactics in which the battery is charged or discharged according to the power demanded while maintaining the constant vehicle speed. On the other hand, the mechanical PnG strategy denotes the powertrain control tactics in which the vehicle accelerates or decelerates according to the power load while minimizing the battery usage. The combined PnG strategy involves both electrical and mechanical strategies to find a balanced point in between them. Here, a tradeoff relationship between the fuel efficiency and the vehicle drivability related to the tracking performance of the desired target speed is revealed.

A physics-based model for SCR (Selective Catalytic Reduction) was developed based on five independent SGB (Synthetic Gas Bench) tests. There are NH3 adsorption & desorption test, NO oxidation test, NH3 oxidation test, SCR reaction (NOx & NH3) test and SV (Space Velocity) test. To validate the accuracy of SCR model’s prediction, transient reactor tests were conducted at four different input conditions. A newly developed SCR model showed more than 90% prediction accuracy in transient test conditions in view of cumulative NOx. Validation of SCR model was conducted on 1.6L light duty diesel vehicle in the WLTC (Worldwide Harmonized Light vehicles Test Cycle). Based upon this SCR model, vehicle level SCR calibrations used for urea dosing control were made and validated in the emission test cycles like WLTC.

There are some problems “windows fog up a lot” for ventilation system. We have Test Development Procedure to prevent the fog problems. But, Many fog problems occurred in the cars that we made. So in this paper, new ventilation system is needed and developed. The Smart Ventilation System automatically controls indoor air quality even though the blower motor is off. There are two sensors that is used for AutoDefogSensor system and CO2 CONTROL system.. The sensor is on when blower motor and heater control is off. We use these signals and make new ventilation logics. We evaluate this system in chamber & '13 winter test in USA.

Electric Power Steering (EPS) needs to meet both functional and stability requirements, it plays significant role in controlling vehicle motion. In the meantime, customers emphasizes natural steering feel which can reflect vehicle motion and road surface information while isolate unwanted external disturbances. In general, conventional EPS control algorithms exert assist torque according to driver torque measured from torque sensor, while maintaining stability using stabilizing compensator. However, there exist significant trade-off between steering feel and stability, because the performances of assist torque control and stabilizing compensator are strongly coupled. In this paper a torque feedback control algorithm for EPS system is proposed in order to overcome the trade-off, and to achieve more natural, robust steering feel.

In commercial vehicles, the exhaust brake assists the service brake to share the excess load and is used as an auxiliary brake to assist with the safety of the engine and the service brake on downhill slopes. To meet the customer's demand for auxiliary brakes, the specification of auxiliary brakes must be determined at the product proposal stage. In this study, performance design was conducted to derive exhaust brake specifications that fit the customer's requirements. For performance design, a system model was created and key design factors with high performance contribution were extracted. Optimal specifications were derived from parameter studies for key design factors. Additionally, performance analysis was performed with design tolerances using the performance design model. Performance was verified through actual vehicle evaluation and design specifications were confirmed.

A study of unsteady compressible flow for two types of exhaust manifold and CCC (Close-Coupled Catalyst) systems attached to a 4-cylinder DOHC gasoline engine was carried out to investigate the flow distribution of exhaust gases and finally to make the conversion efficiency of catalyst better. An experimental study was conducted, using LDV technique, to measure the velocity distributions inside exhaust manifolds and CCC under practical engine conditions. In this study, through experiment and calculation, the effects of geometric configuration of exhaust manifold on flow maldistribution in monolith were mainly investigated to understand the exhaust flow structure in terms of flow uniformity and to improve the conversion efficiency. As a result of this fundamental study, the modified exhaust manifold (Type B) was designed and manufactured. Full load performance tests and vehicle emission tests were performed to see the effects of flow characteristics on engine performance and emission.

In diesel engine development, the new technology is coming out to meet the stringent exhaust emission regulation. The regulation demands more eco-friendly vehicles. Euro6c demands to meet not only WLTP mode, but also RDE(Real Driving Emission). In order to satisfy RDE mode, the new technology to reduce emissions should cover all operating areas including High Load & High Speed. It is a big challenge to reduce NOx on the RDE mode and a lot of DeNOx technologies are being developed. So the new DeNOx technology is needed to cover widened operating area and strict acceleration / deacceleration. The existing LNT(Lean NOx Trap) and Urea SCR(Selective Catalytic Reduction) is necessary to meet the typical NEDC or WLTP, but the RDE mode demands the powerful DeNOx technology. Therefore, the LNT & Urea SCR on DPF was developed through this study.

Road friction estimation algorithms had been studied for many years because it is very important factor for safety control and fuel efficiency of vehicle. But traditional solutions are hard to adapt in automotive industry because their performance is not sufficient enough and expensive to implement. Therefore, this paper proposes a road friction estimation algorithm based on a trained artificial neural-network which is low cost and robust. The suggested method doesn’t need expensive additional sensors such as optical or lidar sensor, also it shows better performance in real car environment compared to other algorithms based on vehicle dynamics. In this paper, we would describe this algorithm in detail and analyze the test results evaluated in real road conditions.

In the latest works [12], we presented the guideline for reducing Metal pick up(MPU, the main component of disc scoring) by controlling the location of the roughness of disc, the brake pad friction coefficients and the disc slot's size. In this study, the previously studied iron transfer theory to 'Cu free' brake pad and the disc surface roughness controlling methods which are based on the mass production manufacturing process are applied. It is possible to suggest the ways to improve the scoring-free disc without reducing friction coefficient between the disc and pad, and any demerit such as increased wear and airplane noise like conventional slot discs [11].

Recently, as part of the effort to enhance fuel efficiency and reduce costs for eco-friendly vehicles, the R-gearless system has been implemented in the TMED (P)HEV system. Due to the removal of the reverse gear, a distinct backward driving method needs to be developed, allowing the Electronic Motor (e-Motor) system to facilitate backward movement in the TMED (P)HEV system. However, the capability of backward driving with the e-Motor is limited because of partial failure in the high-voltage system of an R-gearless system. Thus, we demonstrate that it is possible to improve backward driving problems by applying a new fail-safe strategy. In the event of a high-voltage battery system failure, backward driving can be achieved using the e-Motor with constant voltage control by the Hybrid Starter Generator (HSG), as proposed in this study.

The electrification of the internal combustion engine is an important subject of future automotive technology. By using a motorized internal combustion engine, it is possible to recover waste energy by regeneration technology and to reduce various losses that deteriorate the efficiency of the internal combustion Engine. This paper summarizes the results of the development of an engine-integrated motor that can be applied to a 48V mild hybrid system for motorization of an internal combustion engine. Like the 48V MHSG-mounted mild hybrid system designed to replace the generator in the auxiliary belt system, the motorized internal combustion engine is designed with the scalability as the top priority to minimize the additional space for the vehicle and to mount the same engine in various models.

In recent years, with the advent of the Fourth Industrial Revolution and the COVID-19 pandemic, people's lives worldwide have undergone significant changes. Additionally, the emergence of a new generation of consumers known as the millennial generation has led to a high demand for multipurpose family cars. The perspective is shifting towards choosing premium products that enhance the quality of life and pursue their own happiness and comfort through technology, rather than simply selecting a midsize SUV based on the increase in family size. We aim to meet the needs of these global customers by conducting research and developing various new features that were not previously available in midsize SUVs. In this study, we defined the actual target users for midsize SUVs and established UX concepts by analyzing their characteristics. Based on this, we employed an optimal design approach by analyzing the evaluation results by country for the various features implemented within the vehicle.

Since the fuel efficiency of vehicle has become one of the big issues due to environmental pollution problems, many studies have been conducted on various methods such as improving powertrain performance and aerodynamic performance, reducing the weight of the vehicle and so on. There have been many new attempts to reduce weight but mostly about improving material property. In the case of vehicles sharing the same platform, the weight and cost of vehicle are mainly changed by the exterior styling. But, there is no solution to control the exterior styling in terms of the weight and cost of vehicle, yet. The purpose of this study is to find the way to save the weight and cost of vehicle while achieving the various performance and requirements of vehicle (safety, aerodynamics, driver’s visibility and so on) from exterior styling point of view. We focused on the weight difference of the vehicles that shared the platform and were same overall dimensions.

The high speed continuous braking distance assessment is the worst condition for thermal fades. This study was conducted to investigate the relationship between fade characteristic and friction materials & brake fluid amount for improving braking distance. So, we used the dynamometer to measure the friction coefficient, braking distance and required brake fluid amount. Through the measurements, the research was carried out as follows. First of all, we studied the influence of friction coefficient about different shapes (chamfer shape, area of the friction material, number of slots) on the same friction material. Secondly, we knew the effects of braking distance by the shape of the friction material. Through these two studies, the shape of the friction material favorable to the fade characteristics was derived. Finally, we measured the amount of required brake fluid in caliper after 10 consecutive braking cycles through Dynamometer.

Creep groan noise occurs in a just moving vehicle by the simultaneous application of torque to the wheel and the gradual release of brake pressure in-vehicle. It is the low frequency noise giving the driver a very uncomfortable feeling. Recently, the field claims regarding the creep groan noise are increasing. So far, creep groan noise has been improved by means of chassis modification the transfer system. But vehicle body the response system does not. In this paper, the effect between vibration characteristics of vehicle body, creep groan noise was analyzed. Then presented analysis method for vehicle body effect regarding creep groan noise.

To improve the fuel efficiency and satisfy the strict emission regulations, the development of internal combustion engine gets more complicated in both hardware and software perspectives, and the margins for durability and NVH quality become narrower, which could result in poor NVH robustness in harsh engine operating conditions. In this paper, we investigate experimentally the camshaft impact noise mechanism relating the valve train and timing chain forces to detailed motion of the camshaft and the chain tensioner. After the initial investigation of identifying the impact timings and specific engine operating points when the noise occurs, the camshaft orbital motion inside of the sliding bearing is measured and visualized with the proximity sensors with calibration after sensor mounting, in addition to the chain tensioner movements.

A combined experimental and computational study of 3-D unsteady compressible flow in exhaust manifold and CCC system was performed to understand the flow characteristics and to improve the flow distribution of pulsating exhaust gases within monolith. An experimental study was carried out to measure the velocity distribution in production exhaust manifold and CCC under engine operating conditions using LDV (Laser Doppler Velocimetry) system. Velocity characteristics were measured at planes 25 mm away from the front surface of first monolith and between two monolithic bricks. To provide boundary conditions for the computational study, velocity fields according to crank angle were also measured at the entrance of exhaust manifold. The comparisons of exhaust gas flow patterns in the junction and mixing pipe between experimental and computational results were made.