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In recent years the number of vehicles equipped with millimeter wave radar has been increasing due to the popularization of driving assistance systems such as adaptive cruise control (ACC) and forward vehicle collision warning (FCW) systems. Consequently, high performance millimeter wave radar must be developed to support even more advanced driving assistance systems. The investigation described in this paper confirms that it is possible to use high range resolution radar to recognize the width of a target. In tests, a simulated radar signal was transmitted and received by a millimeter waveband network analyzer using a 1.6 meter-wide aluminum foil board as the target. When the range resolution was low, only one point of reflection from the board could be detected. However, when the range resolution was improved, then multiple points of reflection from the target could be detected.

Electronic stability control (ESC) is being incorporated as a standard feature in almost all passenger cars since it is highly effective in reducing road accidents. Moreover, many commercial vehicles can be equipped with ESC, which includes roll stability control. ESC determines vehicle stability on the basis of the driver's operation, vehicle behavior, and preset control parameters. When the vehicle stability is likely to be lost, control intervenes to stabilize the vehicle. The characteristics of commercial vehicles affect the ESC parameters and vary significantly with the payload (e.g., weight and height of the cargo and the loading state). Therefore, the control parameters need to be adjusted according to the loading conditions to enhance vehicle stability and avoid unnecessary control intervention. We have developed an ESC that improves the yaw and roll stability of trucks. For this development, accurate evaluation of the payload states is important.

From the viewpoint of applying electric resistance welded (ERW) steel tubes for automobile structural parts, the formability degradation of steel sheets in a series of forming steps is investigated. Sheets are subjected several forming steps, such as a roll-forming into tubes, pre-forming, bending and bulge-forming. The formability degradation highly depends on the microstructure and aging property. Deterioration of the formability of sheets is diminished by the existence of the second phase in the ferrite matrix. The formability degradation of the steel sheet having an aging index (A.I.) ≤10MPa is well restrained so that the tube shows a much higher elongation and expanding ratio on bulge forming than the tube having A.I.>10MPa. These phenomena are applicable to all the tubes of tensile strength level form 290MPa to over 590MPa.

This paper presents the results of experimental analysis on the structural performance of steel, aluminum alloy and stampable sheets for bumper beams and the calculation results on the weight reduction of those bumper beams. Bending tests of straight beams, which were made of the three kinds of materials, were carried out in order to examine their structural performance. In consideration of failure modes, it was found that the maximum load and the absorbed energy of those beams can be evaluated by their material strength, their side-wall thickness and the height of their cross sections. Based on this evaluation method, the weight and the absorbed energy of the constant displacement were calculated using a common cross section. The weight reduction of aluminum alloy and stampable sheets is superior to 590MPa high tensile strength steel sheets.