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Recent environmental concerns such as atmospheric pollution and energy conservation have intensified the need to develop pollution-free, energy-efficient vehicles. One such solution is the electric automobile which draws its power from rechargeable batteries. There are few vehicles on the road today because present batteries can store very little energy compared with that of a tank of gasoline. To obtain adequate range, this concept vehicle adopts a new battery which can be recharged to 40% of capacity in six minutes. This super quick charging system makes it possible to recharge the batteries at an electric recharging station just as gasoline-powered vehicles are refilled at service stations. The electric concept vehicle also has improved aerodynamics, reduced rolling resistance and a lighter curb weight, which help to assure adequate range.

FOUR-WHEEL STEERING (4WS) is beginning to find widespread use as a new approach to improving vehicle dynamics, especially in the medium and high speed ranges. Steering the rear wheels in the same phase as the front wheels enhances vehicle stability. Four-wheel steering systems have an even greater potential to improve stability and steering response through suitable control over the transient characteristics of the rear wheel steer angle. This paper traces the course of Nissan research and development work on four-wheel steering and the evolution of Nissan's HICAS (4WS) technology. It also describes research activities under way on vehicle dynamics using a newly developed Simulator Vehicle, equipped with a front and rear angle transient control system which makes it possible to vary the dynamic characteristics of the vehicle instantaneously and at will while driving.

This paper describes the development of a vehicle with four-wheel steering in which the rear wheels can be controlled electronically in addition to the conventional front-wheel steering system. In the method for steering the rear wheels, the side-slip angle at the vehicle's center of gravity is maintained at zero, which improves the basic dynamic properties of the vehicle. This approach allows greater maneuverability at low speed by means of counter-phase rear steering and improved stability at high speed through same-phase rear steering. However, the use of counter-phase rear steering to improve maneuverability gives rise to problems in regard to practicality. In addition, continuously controlled four-wheel steering, using counter-phase at low speed and same-phase at high speed, leads to many other problems regarding practicality because of the strong apparent understeer characteristics.

By means of a new test method for simulating automotive accidents on ordinary roads, we found that while both experienced and inexperienced drivers have the same initial steer input to avoid an unexpected obstacle, experienced drivers display more stable performance in the subsequent control of the vehicle. Further, utilizing driver's transfer functions we studied a mathematical simulation of test results and obtained parameters for both experienced and inexperienced drivers. These indicate that when vehicle yaw response is greatly delayed, inexperienced drivers may lose control, while experienced drivers will secure control of the vehicle.

It is extremely difficult to assure the safety of small cars in an 80 km/h (50 mph) frontal collision with a fixed barrier. As solutions to this problem, we should not only secure occupant survival space in such a collision, but also control body crashworthiness for better operation of the occupant protection system. It is also required that the occupant protection system should display its best performance. This paper discusses the body construction and occupant protection system of the Nissan ESV, designed with a systematic approach and method of matching the body crashworthiness and the occupant protection system.