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It is an important factor in electric vehicles to show customers how much they can drive with the energy of the remaining battery. If the remaining mileage is not accurate, electric vehicle drivers will have no choice but have to feel anxious about the mileage. Additionally, the potential customers have range anxiety when they consider Electric Vehicles. If the remaining mileage to drive is wrong, drivers may not be able to get to the charging station and may not be able to drive because the battery runs out. It is important to show the remaining available driving range exactly for drivers. The previous study proposed an advanced model by predicting the remaining mileage based on actual driving data and based on reflecting the pattern of customers who drive regularly. The Bayesian linear regression model was right model in previous study.

In this study, a novel selective matching logic for a wheel/tire is proposed, to decrease the vehicle driving vibration caused by wheel/tire non-uniformity. The new logic was validated through matching simulation/in-line matching evaluation. A theoretical radial force variation model was established by considering the theoretical model of the existing references and the wheel/tire assembly mechanism. The model was validated with ZF’s high-speed uniformity equipment, which is standard in the tire industry. The validity of the new matching logic was verified through matching simulation and mass production in-line evaluation. In conclusion, the novel logic presented herein was demonstrated to effectively decrease the radial force variation caused by the wheel/tire.

In recent years, the automotive industry has been making efforts to develop vehicles that satisfy customers’ emotions rather than malfunctions by improving the durability of vehicles. The durability and reliability of vehicles sold in the U.S. can be determined through the VDS (Vehicle Dependability Study) published by JD Power. The VDS is index which is the number of complaints per 100 units released by J.D. POWER in every year. It investigates customers who have used it for 3 years after purchasing a new car and consists of 177 specific problems grouped into 8 categories such as PT, ACEN, FCD, Exterior. The VDS-4 has been strengthened since the introduction of the new evaluation system VDS-5 in 2015. In order to improve the VDS index, it is important to gather various customer complaints such as internet data, warranty data, Enprecis data and clarify the problem and cause. Enprecis data is survey of customer complaints by on-line in terms of VDS.

Bad weather conditions such as torrential rain, heavy snow, and thick fog frequently occur worldwide. Vehicle accidents in such bad weather conditions account for a significant portion of all vehicle accidents, and the level of damage is relatively severe compared to other accidents that occur in clear weather. This paper analyzes the driver's driving stability in bad weather conditions, which has such a significant meaning, in various ways through experiments on the inconvenience experienced by the driver. In this study, three levels of bad weather conditions were implemented in a driving simulator environment to evaluate driver inconvenience for six activities. Through driving experiment, quantitative bio-signals and vehicle signals were analyzed in each weather condition. The SD survey was used to assess the driver's inconvenience level for activities performed while driving and analyze the ranking of inconvenience.

In this study it will show, big data analysis and user survey of driving records were conducted to investigate frequency of use and ease of operation of the regen paddle to control one-pedal driving system in electric vehicle. According to 3.8 million driving record big data analysis result, it was found that the driver manipulates 3.31 times on average during a single trip, mainly during the early stages of driving. According to user observation research result in 41.8% of participants did not used or used less than 5 time of regen paddle during one single trip. Also 336 participants, which occupy 83%, responded that the regen paddle manipulation for one-pedal driving was inconvenient. In conclusion, because of the use frequency of the regen paddle is low and the operation of regen paddle is inconvenient. It seems necessary to change the design of the regen paddle.

Today, many automakers are using LED lamp sources in exterior lamps to establish brand awareness and introduce specialized lamp designs. These eye-catching LED lamp source solutions require many control functions as the lamp functions are diversified and advanced, and accordingly the requirements for standardization and optimization of controllers are increasing. In particular, our LED rear combination lamps have a variety of LED loads according to the design of the lamp model, the installation position, and the diagnostic regulations, so that the design complexity and the number of specifications of the controller are increased [4]. In recent years, more and more aesthetic designs and new technologies are used by various automakers to optimize their controllers in cooperation with global partners to optimize costs [1].

For making metal touch feeling and lighting simultaneously, selective electroplating is widely applied in button, panel and etc. in interior/exterior parts of automotive. In this paper, new selective electroplating with printing are suggested as an alternative manufacturing process of two shot molding, PC (Polycarbonate) and ABS (Acrylonitrile-Butadiene-Styrene). Manufacturing process of selective electroplating with printing is as follows: For preventing to plate metal layer in area of letter or symbol, masking ink is printed on parts, button, panel, etc., with electroplatable PC+ABS. After conventional electroplating process, the part has electroplated metal layer except for the printed area. It had been studied the composition of ink and PC+ABS for obtaining skip plating and light transmittance on printed area.

Worldwide projections anticipate a fast-growing market share of the battery electric vehicles (BEVs) to meet stringent emissions regulations for global warming and climate change. One of the new challenges of BEVs is the effective and efficient thermal management of the BEV to minimize parasitic power consumption and to maximize driving range. Typically, the total efficiency of BEVs depends on the performance and power consumption of the thermal management system, which is highly affected by several factors, including driving environments (ambient temperature and traffic conditions) and driver's behavior (aggressiveness). Therefore, this paper investigates the influence of these factors on energy consumption by using a comprehensive BEV simulation integrated with a thermal management system model. The vehicle model was validated with experimental data, and a simulation study is performed by using the vehicle model over various traffic scenarios generated from a traffic simulator.

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.

Drivers continually require steering performance improvement, particularly in the area of feedback from the road. In this study, we develop a new electrically-assisted steering logic by 1) analyzing existing steering systems to determine key factors, 2) modeling an ideal steering system from which to obtain a desirable driver torque, 3) developing a rack force observer to faithfully represent road information and 4) building a feedback compensator to track the tuned torque. In general, the estimator uses the driver torque, assist torque and other steering system signals. However, the friction of the steering system is difficult to estimate accurately. At high speed, where steering feeling is very important, greater friction results in increased error. In order to solve this problem, we design two estimators generated from a vehicle model and a steering system model. The observer that uses two estimators can reflect various operating conditions by using the strengths of each method.

In this paper, we focused on the robust wiping performance of high speed driven condition as an important situation for vehicle safety. Frist, we selected appropriate wiper performance parameter to accurately predict its ability not only systematic point but also vehicle point. Second, we obtained parameter sensitivity of wiper high-speed performance using DFSS technique. Third, we developed prediction and optimization tool using commercial program; Excel and Visual Basic. Finally, we improved our tool to compare vehicle test and then modified prediction coefficient for the accuracy of tool. Thus, we proposed a systematic tool to predict wiping performance in high speed vehicle, and successfully obtained efficiency when we developed the new project’s wiper performance.

The wiper system consists of a motor, linkage, arm, and blade, which provides a clear front view to the driver by removing rain, snow, and foreign matter from the windshield glass. It is a system component that requires a robust design to meet system rigidity, scrubbing performance, and operating noise to any external conditions to provide the driver with a front view. In recent years, however, customer complaints about wiper noise have increased as automobile engine and noise levels have decreased. Based on the analysis of wiper noise, this paper presents quantitative judgment criteria for various wiper noises. In addition, we predict the change of wiper noise to environmental factors through the sound field analysis and propose the solution.

APAS refers to a low speed sound warning system of electric vehicles, which emits alerting sound only to target pedestrians by sound focusing techniques with array of speakers and object detective camera. In the present study, experimental and numerical investigations are conducted in designing speaker part and array of APAS with consideration of three main performance matrices; HEV/EV warning sound regulations in Europe and U.S., pedestrian awareness, and driver’s noise comfort. The present APAS speaker consists of back enclosure, wave guide and front grill. Each of these components plays an important role for characterizing frequency emphasis and sound directivity. The main impedance frequencies of the speaker are determined by considering warning sound regulations and also by analyzing acoustic frequency response at in/outside of a vehicle.

The mass producible broad-band ANC system for road noise is developed with fully digital control system. For this configuration, installation packages are intensively considered by minimizing size of the controller, simplifying wiring system and implementing virtual microphone techniques. Virtual microphone technique enables error microphone to be installed in remote position of driver’s ear, and therefore, increases installation degree of freedom significantly. To enhance noise control performance with the minimum latency, filter design of FxLMS algorithm is optimized while additional audio compensation techniques are applied to maintain audio performance of amplifier. The present ANC system is equipped to HMC (Hyundai Motor Company) new release of hydrogen driven vehicle, which is introduced in the technology promotion event in Pyeongchang Olympic 2018.

Suspension is a system which operates dynamically according to road condition unlike other system statically mounted to the body. Especially this is more remarkable in high performance vehicle because there are more high inputs from road to suspension than normal vehicle. For this reason, the tightening torque of suspension system of high performance vehicle is more important than other systems and normal vehicle. To support the clamping between parts against force from road when cornering, optimized tightening torque is required to maximize R&H performance. For this optimization, it should be conducted first to comprehend how much performance effects on vehicle by tightening torque. This paper presents relationship between tightening torque of suspension parts hardware and R&H performance.

The weight reduction of the car suspension parts has a direct influence on the ride and handling. However, the application of nonferrous metal materials, such as aluminum and magnesium, which results in a lighter weight of the suspension can lead to an increase in manufacturing costs compared to cast iron. In this study, vertical type high-pressure die casting using by electro-magnetic stirring (EMS) with A356 alloy in the sleeve was used to control the fine microstructure. Process optimization and part development, as well as unit product and automotive assessment were carried out for electro-magnetic stirring methods. Without making the slurry, the mechanical properties were obtained through optimization of process variables UTS 320MPa, YS 239MPa, EL 13.3%. It also succeeded in mass production with minimum cost increase of aluminum suspension components.

The driver’s seat in heavy trucks is designed for an upright driving posture with narrow back and cushion angles; thus, the seatback offers very little support. This makes the sitting posture prone to shifting during long trips, leading to loss of comfort and increase in fatigue. Sitting posture stability allows initial posture to be maintained during long drives, and the lack of stability causes fatigue and body pain during the drive. This study confirmed that enhancement of sitting posture stability of the driver’s seat in heavy trucks requires appropriate support from the cushion. The study also analyzed the support characteristics of each part of the cushion, and presented development guidelines of new cushion. Although subjective assessments of sitting posture stability have been performed, this study presented a method for quantitative and efficient assessment of sitting posture stability using the PAM-COMFORT simulation tool and virtual testing.

Conventional EPS (Electric Power Steering) systems are operated by one type of steering tuning map set by steering test drivers before being released to customers. That is, the steering efforts can't change in many different driving conditions such as road conditions (low mu, high mu and unpaved roads) or some specific driving conditions (sudden stopping, entering into EPS failure modes and full accelerating). Those conditions can't give drivers consistent steering efforts. This paper approached the new concept technology detecting those conditions by using vehicle and EPS sensors such as tire wheel speeds, vehicle speed, steering angle, steering torque, steering speed and so on. After detecting those conditions and judging what the best steering efforts for safe vehicle driving are, EPS systems automatically can be changed with the steering friction level and selection of steering optimized mapping on several conditions.

In order to design the in-wheel motor (IWM) for Electric Vehicles (EV), it is necessary to analyze the desired (expected) duty cycle at a higher performance level in order that the IWM becomes commercially relevant. The duty cycle may be representative of different segments of the customer base. Or, the individual customer may wish to have a set of IWMs that uniquely meet his/her measured “demand” cycle for a balance of drivability and efficiency. Questions then arise: How to measure the demand cycle of an individual? What 2 or 3 standard duty cycles should be offered as customer choices for their vehicle? Should the IWM represent multiple speed domains to enhance efficiency and drivability? Can the vehicle be updated rapidly 2 to 3 years after purchase? Etc. In this paper, we lay the groundwork to answer these types of customer questions for an EV with four independent IWMs.

In general, driving performance is developed to meet preference of average customers. But there is no single standardized guideline which can satisfy various driving tastes of all drivers whose gender, cultural background, and age are different. To resolve this issue, automotive companies have introduced drive mode buttons which drivers can manually select from Normal, Eco, and Sport driving modes. Although this multi-mode manual systems is more efficient than single-mode system, it is in a transient state where drivers need to go through troubles of frequently selecting their preferred drive mode in volatile driving situations It is also doubtful whether the three-categorized driving mode can meet complex needs of drivers.. In order to settle these matters, it is necessary to analyze individual driving style automatically and to provide customized driving performance service in real time.