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First, this paper focuses on classification of near-miss incidents with pedestrian into typical scenarios, and then incident data are analyzed under the assumption that pedestrian detection system has a pre-determinant sensing performance. The data of 220 near-miss incidents with pedestrian when own vehicle goes straight are employed. We proposed a set of eight scenarios which structure is not necessarily hierarchical. The eight scenarios cover about 75% of the incidents. To highlight the characteristics of the eight scenarios, two kinds of vector-diagrams are introduced which illustrate the transition of relative position between pedestrian and own-vehicle, and TTC-TTV (Time To Collision - Time To Vehicle) relation respectively. For example, in a relative position diagram, we can grasp the pedestrian's relative position which the detection system finds the pedestrian first when he/she appeared with pre-determinant wide detection angle.

Electric vehicles usually have shorter cruising range because of their limited battery capacity. Various kinds of field operation tests on their user acceptance have been executed in all parts of the world. The authors carried out one-year field test using two types of EVs in the market. They were served for tourism use or general use. The field is mountainous area with a low population density and heavily snow-covered in the winter season. This paper mainly reports the impacts of road gradient and temperature change on their energy consumption (or electric mileage) in such severe driving environment for EV operation.

A high-performance road profile measuring system has developed. The measuring system consists of four laser displacement sensors and an optical speed sensor. It has the advantage of making high-accuracy measurements during a regular run, on a public road, and without any traffic restriction. The measurement is hardly affected by bouncing and pitching motions of the vehicle. The four displacement sensors are arranged at unequal intervals in the direction of vehicle. A road profile is calculated from sensor outputs. This paper describes not only the development of this unique measuring system but also its application to a vehicle behavior. Significant measurements of typical and peculiar public roads in Japan and Northern Europe by the measuring vehicle have been performed for the last few years. The features of these roads are described by the power spectrum densities and the profiles.

There are many meaningful numerical evaluations of vehicle dynamic performance. However, evaluation methods using one or two parameters have little practical use for development of new cars or for comparison of similar cars since drivers' preferences vary widely in various handling characteristics. We developed the Four Parameter Evaluation Method. The parameters are extracted from lateral transient response data by curve fitting with a two degree of freedom model. Intuitively, we can recognize vehicle performance by arranging these four parameters in a rhombus. This expression is suitable for complex handling characteristics. The resulting rhombus pattern reflects a rather small difference between test cars including 4WS.

Application of active control technology to an automobile has been considered to be effective to drastic improvement in vehicle dynamics (1,2,3,4)*. This paper studies maneuvability and stability of vehicles with active-controlled suspension and four wheel steering system. System construction and effects of the active control are also described.