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A lot of countermeasures have been developed in order to reduce interior noise. For example, improvements of rubber mount characteristics and other measures have been implemented. Recently electromagnetic active engine mounts based on a hydraulic engine mount have been developed. They are significantly effective for the reduction of the booming noise which is unpleasant for passengers. Although the LMS algorithm has been generally used for the active control, it has been used only for reducing booming noise. The authors developed a new control method in order to reduce not only the booming noise but also the noise and the vibration over wide frequency band for comfortable vehicle interior space. The authors studied the method which determines the feedback gain according to various conditions by modifying LMS algorithm. In this modified LMS algorithm, only an error signal was used as an input signal.

Lane Centering Control System (LCCS) is a lateral Advanced Driving Assistance System (ADAS) with low acceptance. One of the main reasons is that the centering trajectory can’t satisfy different drivers, which is more obvious in the curve condition. So LCCS adaptive to different drivers needs to be designed. The trajectory planning module is an important part for LCCS. It generates trajectory according to the road information for the vehicle control module to track. This paper uses road information obtained from the scenario established in Prescan, and the trajectory planning method proposed can generate trajectories for different drivers in the curve condition. To achieve the goal, this paper proposes a trajectory planning method which contains lateral path planning and longitudinal speed planning. Firstly, the overall strategy of “road equidistant segments division” is used to describe the road information.

This paper describes the classification algorithm of the driving steering intention based on brain-computer interface (BCI) using electroencephalogram (EEG). The classification algorithm of the driving steering intention was examined and developed. Experiments were conducted with 3 able-bodied subjects using driving simulator (DS). The drivers were instructed to operate the vehicle according to the series of three kinds of instructions (right steer, left steer, and straight running). Those instructions were given to the subject with random order, after the operation trigger had been signaled. The off-line analytical result shows that the driver's steering intention can be classified at the averaged probability of about 80%.

The purpose of this study was to find factors to improve the performance of louvered fins through visualization of air flow in the louvered portion of the fins. As part of this study, three dimensional enlarged models were used to visualize and examine the basic flow in the fins. Also, more complicated flows induced by bend configuration (or inclination of fins), which are caused by large fin pitch, have been visualized and examined. The latter flow pattern could not be observed in two dimensional models.

In Japan, the number of occupant fatalities has decreased at high ratio due to the development of passive and active safety technology in recent years. However, the pedestrian fatality is still the major proportion of fatalities according to the statistics of traffic accident. Therefore, it is important to study and develop active safety technologies which target to pedestrian. By analyzing the traffic accident statistics, narrow road in urban area is one of the dangerous parts for pedestrian. And the dangerous case that pedestrian often gets into an accident is while crossing road outside of crosswalk. This study focuses on accidents which are caused by pedestrians suddenly crossing narrow urban roads. In such cases, drivers need to drive carefully, preparing for sudden crossing or unexpected dangerous behavior of pedestrians. Therefore, it is important for drivers to predict the accident risk due to the crossing pedestrian behavior in such narrow roads.

Steering reaction torque is one of the most important types of information for drivers since it has significant influence on vehicle maneuverability. Even with today's advanced simulation technology, however, it is very difficult to accurately simulate steering feeling. The purpose of this study is to develop a steering Hardware-in-the-Loop (HIL) simulator that can quantitatively evaluate steering systems. This simulator can control the force on the tie rod with simple mechanism. The validity of this HIL simulator has been ascertained by comparing the simulation results with those obtained during actual vehicle testing.The preliminary research concerning the advanced simulators based on the developed HIL simulator is also reported.

This paper proposes a driving torque control algorithm of micro-scale electric vehicle (NOVEL-I) at the scene of preceding vehicle following. First, an inter-vehicle distance controller aiming to keep a safe inter-vehicle distance is designed. Next, the experiments of vehicle following situation by automatic driving with the designed controller are realized and the effectiveness of the controller is verified. Next, the designed controller is applied to the human-vehicle closed-loop system as driver assistance systems, thereby enhancing driving comfort and reducing driving workload for human. Finally, the experiment of vehicle following by cooperative driving between the human and the controller is conducted. The experimental result in cooperative driving is compared with manual driving, and the effectiveness of the controller is verified.

Lane Keeping Assistance (LKA) system is a very important part in Advanced Driver Assistance Systems (ADAS). It prevents a vehicle from departing out of the lane by exerting intervention. But an inappropriate performance during LKA intervention makes driver feel uncomfortable. The intervention of LKA can be divided into 3 parts: intervention timing, intervention process and intervention ending. Many researches have studied about the intervention timing and ending, but factors during intervention process also affect driver feelings a lot, such as yaw rate and steering wheel velocity. To increase driver’s acceptance of LKA, objective and subjective tests were designed and conducted to explore important indices which are highly correlated with the driver feelings. Different kinds of LKA controller control intervention process in different ways. Therefore, it’s very important to describe the intervention process uniformly and objectively.

Active Control Technology (ACT) has been applied to the improvement of dynamics of ground vehicles, such as ride quality, running stability and handling performances of automobiles. In this paper, the two degrees-of-freedom (two-DOF) model of automobiles with a semi-active suspension is analyzed theoretically using computer simulation. A nonlinear feedback control system by which the coefficient of the damper force is continuously modulated is proposed and analyzed to discuss the vibration suppression characteristics when the vehicle is excited by a random road surface.