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This paper introduces the advancement of Engine Idle Stop-and-Go (ISG, also known as Auto Engine Stop-Start) and Neutral Coasting Control (NCC) with utilizing Advanced Driver Assistance System (ADAS) and GPS. The ISG and the In-Neutral Coasting (also known as Sailing or Gliding) have been widely implemented in recent vehicles for improving their fuel economy. However, many drivers find them somewhat disturbing because they basically change behaviors of their cars from what they used to. This annoyance discourages usages of those functions and eventually undermines their benefit of fuel saving. In order to mitigate the problem, new ISG and NCC algorithms are proposed. As opposed to the conventional logics that rely only on driver’s pedal action, the new algorithms determine whether or not to enable those functions for the given driving condition, based on the traffic information obtained using ADAS sensors and the location data from GPS and navigation map.

A vehicle simulation model is developed, validated and integrated into a closed-loop virtual driving environment using a state-of-the-art hexapod driving simulator. Thirty variant states are implemented and evaluated subjectively on steering and handling performance quality and quantity. Standard open-loop objective testing manoeuvres are simulated and performance metrics are calculated, allowing for a systematic cross-correlation process. Graphical analysis of the correlation metrics proves that chassis changes may accurately be felt through the simulator interface. It is proposed how obtained correlation models may serve for driver-feel optimizing target setting in early vehicle development stages, frontloading a great deal of costly prototype testing. System requirements are established and benefits and limitations are portrayed.

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. It is caused by the stick-sleep phenomenon at the lining and disc interface. Recently, the field claim of low frequency creep groan has increased. There are a lot of efforts to improve creep groan noise by means of modification of lining material. In this paper, Transfer path of creep groan noise was analyzed through ODS and TPA. Additionally the correlation between Source (Brake torque variation, Brake vibration) and Creep Groan Sound level was discussed. Finally countermeasure to Creep Groan noise was suggested.

This paper proposes an effective nonlinear bicycle model including longitudinal, lateral, and yaw motions of a vehicle. This bicycle model uses a simplified piece-wise linear tire model and tire force tuning algorithm to produce closely matching vehicle trajectory compared to real vehicle for wide vehicle operation ranges. A simplified piece-wise tire model that well represents nonlinear tire forces was developed. The key parameters of this model can be chosen from measured tire forces. For the effects of dynamic load transfer due to sharp vehicle maneuvers, a tire force tuning algorithm that dynamically adjusts tire forces of the bicycle model based on measured vehicle lateral acceleration is proposed. Responses of the proposed bicycle model have been compared with commercial vehicle dynamics model (CarSim) through simulation in various vehicle maneuvers (ramp steer, sine-with-dwell).

A traffic situation is getting more complex in urban areas. Various safety systems of an automobile have been developed but fatal and serious accidents still can be made by driver's faults or distractions. The system supporting extend of driver's recognition area is going to be an important part of future intelligent vehicles in order to prevent accidents. In this paper we propose sensor fusion system based on a digital-map for driver assistance. The accurate localization of a host vehicle is achieved by a stereo vision sensor and a digital-map using polygon matching algorithm in urban area. A single-row laser scanner is used for tracking multiple moving objects. The coordinate transformation from sensor frame to global frame is performed to visualize the moving objects on a digital-map. An experiment was conducted in an urban canyon where the GPS signals are frequently interrupted.

Recently, in accordance with the increased interest of consumer in fuel efficiency due to the phenomenon of high oil price, complaints against actual fuel efficiency in the road in comparison with the certified fuel efficiency have been raised frequently. Especially in case of the hybrid vehicle which is highly popular for the reason of its high fuel efficiency compared with that of existing gasoline car, deviation in the fuel efficiency will be higher compared with that of gasoline car in accordance with the driving mode (downtown/highway), driver's driving style (wild/mild) and external environmental condition (gradient/temperature/altitude). To solve them, this paper developed a method so that the SOC (State Of Charge), EV/HEV mode transition point can be controlled variably in accordance with the driving mode, driver's driving style and external environmental condition by making the most of characteristics of hybrid.

The Eco-driving indicator is a colored lamp on a cluster to lead a driver to smoothen acceleration of a vehicle. Informed by the indicator, a driver learns how deep to push a gas pedal for a better fuel economy. The Eco-driving guide system outputs a vehicle fuel efficient state by the Eco-driving indicator. It is based on BSFC map, engine torque map, A/T shift pattern data, engine operation status and transmission operating status. With the Eco-driving guide system, vehicle fuel efficiency can be improved by 4∼26%.

Hands-free stability, one of the handling characteristics of a vehicle, is a stability criterion evaluated in case of a driver's steering wheel release after a certain steering input during driving. During the development process, a hands-free-unstable vehicle needs many steering and suspension parts to be repeatedly tested to improve the performance. In this paper, CAE methods are proposed to investigate easily the influence of the steering and suspension design parameters on the hands-free stability. And the results of CAE methods were compared with the prototype vehicle test to verify the validity of the methods.

Conventional steering system has a mechanical connection between the driver and the front tires of the vehicle, but in steer-by-wire system, there is no such a connection. Instead, actuators, positioned in the vehicle's front corners receive input from the control module and turn the front wheels accordingly. In steer-by-wire system, steering wheel is an important part that not only transfers driver's steering input to the controller but also provides a road feedback feeling to the driver's hand. Thus the reactive torque actuator, providing road feedback, plays an important role in steer-by-wire system. In conventional steer-by-wire-system, a motor was used as a reactive torque actuator. But using motor has some disadvantages such as an oscillatory feeling, and improper and potentially dangerous acceleration of the steering wheel by the motor when driver's hands are released from steering wheel abruptly.

This paper presents an in-vehicle information system, AVICS in development. With AVICS, the driver could get the various information on traffic, news, weather, restaurants, and so on, which the AVICS information center provides via mobile telecommunication network. The driver requests the information to operator in center by voice with hands-free system or by handling the menu offered in the form of web-page. The in-vehicle unit for AVICS is designed to interface with wireless network with a built-in RF MODEM, to control NAVI system, and to display the information on the LCD monitor of AV system. The Internet browser is customized to parse specific HTML tags, application software is realized on 32-bit RISC processor. In this paper, we will overview the concept of AVICS and focus on development of in-vehicle unit of AVICS.