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Development of a system which utilizes technology for the recognition of a vehicle's surroundings. Research is currently taking place in many countries, the goals of which are to improve a vehicle's safety and convenience by reducing driver strain through the automation of the recognition, judgment, and operation capabilities that are needed when driving an automobile. To recognize the vehicle's surroundings, we have adopted an image sensor system which offers superior three-dimensional recognition capabilities. In this paper, we will introduce a inter vehicle distance control system which controls the vehicle's throttle and braking functions by detecting the position of the driving lane and the distance to the vehicle in front based on the images obtained by a CCD camera.

In a system with which acceleration and braking by the driver are automated, a gap against the system can be felt when the timing of acceleration or deceleration is different from that intended by the driver or the extent of acceleration or deceleration exceeds an acceptable limit. For an automated system, it is important to realize a control that provides comfort and a sense of security for the driver. This paper is related to the technology that secures the ride comfort felt by the driver (comfort and a sense of security) within an appropriate range and presents a discussion of the technological means to improve the ride comfort from a viewpoint particularly related to longitudinal direction.

Rear steering system can improve vehicle stability using active control of the rear wheel angles. For designing the rear steering system, environmental conditions, performance deterioration due to aging and component variation as a result of manufacturing tolerance under mass production must be taken into consideration. We have applied two-degree-of-freedom (2DOF) feedback control with feedforward control for the motor servo control so that the rear steering actuator can track the target rear steering angle accurately and stably. The control system is designed based upon a nominal mathematical model and its variation range. As a result, the rear steering actuator can be controlled with excellent performance and high reliability. This paper describes the mathematical model construction in the frequency domain and a robust motor servo controller design based on 2DOF feedback control with feedforward control.

This paper reports the results of a study into a preview control that uses the displacement of the road surface in front of the vehicle to improve for front and rear actuator responsiveness delays, as well as delays due to calculation, communication, and the like. This study also examined the effect of a preview control using the eActive3 electric active suspension system, which is capable of controlling the roll, pitch, and warp modes of vehicle motion.

We have developed Sensor-less Memory Seat system that requires no position sensors such as Hall ICs etc.. It detects the rotation of DC motor by current ripple signals in motor operating current. The developed Sensor-less position control system can attenuate a wide frequency variation of Motor current noise which varies depending on motor condition and convert small current ripples to Pulse signals in proportion to the rotation of DC motor. We realized low cost position control method for use in Memory Seat system.

An active suspension system controls a spring constant and an attenuater in real time using a power supply. Generally, the hydraulic pressures are used for transmitting the power. Therefore, a highly reliable and inexpensive control system has been required for a commercial use. This has been achieved by developing a mechanical fluid servo valve which comprises a simple combination of a solenoid valve and a spool valve. The technical problem of the valve vibrations has been solved through the numerical analyses, the fluid flow visualization tests and the vehicle tests.