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This paper concerns driver's burden for visual information processing in which his central vision is coupled with his peripheral one. A visual driving simulator was applied to the first step of the study, where driver's responses to both central and peripheral tasks were simultaneously investigated. The series of test indicate that the driver's responsiveness to the central and peripheral tasks could define the whole burden for visual information processing. Therefore, it appears that the responsiveness to the peripheral vision could be more or less compromised to support the central one.

This paper describes a method of predicting cooling performance in order to obtain the optimum design of the cooling system and front-end shape in the early stage of car development. This method consists of four calculation parts: thermal load on the cooling system, air flow through the engine compartment, heat dissipation by the heat exchangers and temperature distribution within the cooling system. It outputs the coolant, engine oil, automatic transmission fluid (A.T.F.) and charge air temperatures in exchange for the input of several car, power plant, drive train, exterior shape and cooling system specifications. For the calculations, in addition to theoretical formulas, several experimental formulas are introduced. This method verification is shown by presenting a few test cases for the respective calculation parts and the final solution.

It has been over a half century since automatic transmission vehicles were introduced to the market, and many improvements in terms of reliability, performance, and cost have since been made. As a result, over 70 percent of passenger cars in the Japanese market today are equipped with automatic transmissions. Despite these advances, customer demand for quieter operation and reduced vibration in automatic transmission vehicles requires further improvements, particularly in the area of reduced shock and smooth response during shifting. Technological improvements have been in progress to solve this problem by such means as reducing engine output during shifting, adapting feedback control and learning shift control. Consequently, an advanced evaluation method for shift quality, with accuracy matching that of human feeling, is required to help improving the shift quality of automatic transmissions.

This paper examines the anti-shudder property of automatic transmission fluid (ATF) in terms of evaluation criteria and durability. The anti-shudder property is required for precise slip control around the clutch in that kind of automatic transmission, applications which are currently increasing. To evaluate anti-shudder properties, friction characteristics are measured by modified Low Velocity Friction Apparatus (LVFA), and the data are compared with those from the actual vehicle. The analysis confirms that the occurrence of shudder on the vehicle is closely related to the ratio of the static friction coefficient to the dynamic one measured by modified LVFA.

From the standpoint of safety, the demands are growing in recent years for better controllability and stability of automobiles and in particular in trucks. The truck, however, when compared with the passenger car, is subject to larger changes in gross vehicle mass and center of gravity depending on its load placement. In addition, since the cornering power generated by the truck tire per load is smaller than that generated by the passenger car tire, it is difficult to introduce significant improvements in controllability and stability simply by use of passive techniques like suspension characteristic tuning. Therefore, studies were performed on the applicability of the 4WS system, an active vehicle dynamic characteristic control technique, to a Truck as a means for solving these problems.

Various parameters for the shift scheduling of an automatic transmission were examined to detect more accurate road conditions, vehicle running conditions, and the driver's intention. The parameters include the vehicle speed, the gradient of a road, an index to curves in the road, and so on. The fuzzy logic was employed to incorporate these parameters into the shift scheduling control. The vehicle running tests have shown that the use of many parameters and the fuzzy logic was effective on reducing the frequencies of the transmission gear shift and the driver's brake operation in such road conditions as usually seen in mountainous areas