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As the original engine sound is usually not enough to satisfy the driver’s desire for a sporty and fascinating sound, Active Noise Control (ANC) and Active Sound Design (ASD) have been great technologies in automobiles for a long time. However, these technologies which enhance the sound of vehicles using loud speakers or electromagnetic actuators etc. lead to the increase of cost and weight due to the use of external amplifiers or actuators. This paper presents a new technology for generating a target sound by the active control of a permanent magnet synchronous motor (PMSM) of a mass-production steering system. The existing steering hardware or motor is not changed, but only additional software is added. Firstly, an algorithm of this technology, called Active Sound Generation (ASG), is introduced which is compiled and included in the ECU target code. Then the high frequency noise issue and its countermeasures are presented.

Due to technological evolutions and social demands, motor vehicles are requested to be enhanced in terms of occupant safety and comfort. As a result, many countries are reinforcing crash regulations and new car assessment programs. Automotive seats are essential parts for providing passenger safety and comfort and have become most important. Many automotive companies concentrate on optimization of the seat structure. This paper presents an overview of the recent evolution of the seat structures and gives a development procedure covering seat frame design, optimization and validation. Through the study, a competitive frame design is drawn as a case result and a design guideline and a standard development procedure is established

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.

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.

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.

Currently, diesel engine-out exhaust NOx emission level prediction is a major challenge for complying with the stricter emission legislation and for control purpose of the after-treatment system. Most of the NOx prediction research is based on the Zeldovich thermal mechanism, which is reasonable from the physical point of view and for its simplicity. Nevertheless, there are some predictable range limitations, such as low temperature with high EGR rate operating conditions or high temperature with low EGR rates. In the present paper, 3 additional considerations, pilot burned gas mixing before the main injection; major NO formation area; concentration correction, were applied to the previously developed real-time NO estimation model based on in-cylinder pressure and data available from ECU. The model improvement was verified on a 1.6 liter EURO5 diesel engine in both steady and transient operation.

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%.

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.

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.

Customer vehicle usage monitoring is one of the most fundamental elements to consider in the process of developing a durable vehicle. The extant method to research customer vehicle usage takes considerable time and effort because it requires attaching a series of sensors to the vehicle-gyroscope, accelerometer, microphone, and GPS-to gather information through data logs and then to analyze data in a computer where designated analyzing software has been installed. To solve the problem, this paper introduces a new concept of integrated system developed to examine customer vehicle usage that can analyze data by collecting it from a variety of sensors installed on a smartphone.

To meet Euro6 regulation particulate matter MEMS sensor is suggested. This sensor detects induced charges by PM. To increase sensitivity of the sensor, surface area of the sensor is increased by MEMS process. Sensor is made by low resistive silicon. Total size is 4.3 mm x 59.4 mm x 1 mm and size of sensor part is 4.3 mm x 13 mm. On the backside of the sensor, Pt heater is fabricated to remove piled PM on sensor part. After sensor part, charge amplifier is used to measure the induced charge of the sensor. From FFT of sensor signal, it can sense 5.46 mg/m₃ of PM. In this paper, MEMS devices for exhaust system monitoring of automobiles are investigated. PM emitted from diesel engine is charged particle. Charge-induced-type PM sensor we designed can measure by real time and it doesn't need particle collection apparatus

The electrical power system is the vital lifeline to most of the control systems on modern vehicles. The demands on the system are highly complex, and a detailed understanding of the system behavior is necessary both to the process of systems integration and to the economic design of a specific control system or actuator. The vehicle electric power system, which consists of two major components: a generator and a battery, has to provide numerous electrical and electronic systems with enough electrical energy. A detailed understanding of the characteristics of the electric power system, electrical load demands, and the driving environment such as road, season, and vehicle weight are required when the capacities of the generator and the battery are to be determined for a vehicle. An easy-to-use and inexpensive simulation program may be needed to avoid the over/under design problem of the electric power system. A vehicle electric power simulator is developed in this study.

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 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.

The large luxury sedan seat has a 22-way Movement. It offers a wide range of adjustments to enhance passenger comfort performance while it has many constraints on movement in constrained indoor space. In addition, the power seat is operated by a motor, which makes it difficult for the user to determine the amount of adjustment, unlike determining the amount of adjustment by the power and feel of a person, such as manual seat adjustment. IMS, one-touch mode, is also constrained by parameters such as indoor space package, user's lifestyle, etc. during function playback. This paper aims to design the seat control logic to achieve the best seat comfort while satisfying each constraint. The results of this study are as follows. Increase robustness of power seat control logic. Provide optimal adjustments and comfort at each location. Offer differentiated custom control and seating modes for each seat. Improve customer satisfaction and quality by upgrading software.

Although subjective measurements are critical for qualifying seat comfort in terms of good or bad, objective measurements are the basis for quantifying these differences and ultimately controlling seat comfort performance through engineering design specs, targets, and/or guidelines. Many objective automotive seat comfort tools and techniques used today are based on methods derived in the past. This paper examines the engineering problems and solutions that make these historical influences relevant today. Particular focus is given to design considerations for the A-surface, B-surface, and the compressed surface of the seating system.

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.