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The accuracy of FE (Finite Element) side impact dummy characteristics is important when using FE vehicle model for vehicle development. This study evaluated the response characteristics of FE SID-lls dummy (5TH female) model that was developed by FTSS using FE code PAM-CRASH™. This paper will describe improvements of computational evaluation method and FE dummy model in the sled tests simulated interior. For the various impact conditions, good correlation between FE calculation and the sled test results was obtained.

Flat panel displays for automobiles are facing a new era with the development of navigation systems. As navigation systems become more important as driver's assistance devices, development of birds-eye-view and 3D displays continues, as well as improvements for larger display screens and higher mounting positions. In response to the progress of mobile multimedia technologies, demands for larger display screens and larger aspect ratios have been increasing. Significance for improvements to anti-glare features or view angles has increased as they provide better visibility and the increase layout options. The use of human machine information interaction, which interfaces visual, audio and tactile senses, makes it possible to realize safer, more convenient and comfortable multimedia era vehicle

A block-on-ring friction and wear testing machine (LFW-1) was used as a test method for making fundamental evaluations of the effect of the Belt-Drive Continuously Variable Transmission(B-CVT) fluid on the friction coefficient between the belt and pulleys. The results confirmed that this method can simulate the friction phenomena between the belt and pulleys of an actual transmission. The mechanism whereby ZDDP and some Ca detergents improve the torque capacity of a B-CVT was also investigated along with the effect of the deterioration of these additives on the friction coefficient. It was found that these additives form a film, 80-90 nm in thickness, on the sliding surface, which is effective in increasing the friction coefficient. The friction coefficient declined with increasing additive deterioration. The results of a 31P-NMR analysis indicated that the decline closely correlated with the amount of ZDDP in the B-CVT fluid.

Cold forging has been applied to form a component of the constant velocity joint. This part, slide joint housing, is made of JIS S48C (SAE 1048) high carbon steel. As it has been very difficult to form this part by cold forging, it has been formed by hot forging up until now. Success was obtained in forming this part by cold forging through improving the chemical composition of S48C high carbon steel and tool design, determining the optimum condition for heat treating the slug, and using a TiC coated punch. Since this slide joint housing, which is nearly net shape, was able to be formed through this cold forging technique, material saving was improved about 40% and machining time was reduced much in comparison with hot forging. Manufacturing cost can be greatly reduced through this cold forging which has been developed.

The demands on valve seat insert materials, in terms of providing greater wear-resistance at higher temperatures, enhanced machinability and using non-environmentally hazardous materials at a reasonably low cost have intensified in recent years. Due therefore to these strong demands in the market, research was made into the possibility of producing a new valve seat insert material. As a result a high speed steel based new improved material was developed, which satisfies the necessary required demands and the evaluation trials, using actual gasoline engine endurance tests, were found to be very successful.

Generally, cobalt-contained sintered materials have mainly been applied for exhaust valve seat inserts (VSI). However, there is a trend to restrict the use of cobalt as well as lead environmental law, and cobalt is expensive. To solve these problems, a new exhaust VSI on the assumption of being cobalt and lead free, applicable for conventional engines, having good machinability, and with a reduced cost was developed. The new exhaust VSI is a material dispersed with two types of hard particles, Fe-Cr-C and Fe-Mo-Si, in the matrix of an Fe-3.5mass%Mo at the ratio of 15 mass % and 10 mass % respectively.

Nissan has now developed a second-generation ceramic turbocharger, improving upon its original ceramic turbocharger in order to meet the increasingly demanding requirements of drivers.

It is well understood that using lower viscosity engine oils can greatly improve fuel economy [1, 2, 3, 4]. However, it has been impossible to evaluate ultra-low viscosity engine oils (SAE 0W-12 and below) utilizing existing fuel economy test methods. As such, there is no specification for ultra-low viscosity gasoline engine oils [5]. We therefore developed firing and motored fuel economy test methods for ultra-low viscosity oils using engines from Japanese automakers [6, 7, 8]. This was done under the auspices of the JASO Next Generation Engine Oil Task Force (“TF” below), which consists mainly of Japanese automakers and entities working in the petroleum industry. Moreover, the TF used these test methods to develop the JASO GLV-1 specification for next-generation ultra-low viscosity automotive gasoline engine oils such as SAE 0W-8 and 0W-12. In developing the JASO GLV-1 specification, Japanese fuel economy tests and the ILSAC engine tests for evaluating engine reliability were used.

This paper describes a newly developed microcomputer-based drowsiness warning system, which detects changes in the driver's alertness through his steering behavior. In developing this system, we first quantified several levels of alertness based on such physiological factors as brain activity and blinking. Tests were then conducted in which drivers fell into different degrees of drowsiness. Using the quantified alertness levels, we defined the “drowsy driver” and found unique steering patterns that could not be seen in normal driving. These patterns were entered into the memory unit of the microcomputer. When the sensor built into the steering wheel detects a drowsy steering pattern, the microcomputer recognizes the driver's drowsiness and activates a buzzer to warn the driver. In this paper, the process of determining the alertness levels is explained, along with the steering characteristics of the drowsy driver.

To reduce engine exhaust emissions, we have had to deal with this global environmental problem from the fuel side by introducing oxygenated fuels, reducing the RVP and using low aromatics. But when we change the fuel components and distillation, we must take note about how these affect the engine driveability. We have used T50, T90, RVP and so on as the fuel index up to the present. It is possible to characterize the fuel from one aspect, but these indexes don't always represent the real feature of the fuel. In this paper we propose a New Driveability Index (here in after referred to as NDI) that is more realistic and accurate than the other fuel indexes. We used a 1600cc DOHC L4 MPI type engine. We used Model Gasolines and Market Gasolines, see Appendix(1), (2) and (3), and tested them according to the Excess Air Ratio Response Test Method (here in after referred to as λ-R Test) that was suggested in SAE paper #930375, and we calculated the NDI statistically.

A research prototype driver support system to augment perception to enhance situation awareness and control for car following applications is introduced and results from a field test evaluation are reported. The support system applies driving and braking force control and a gas-pedal push-back force whose magnitudes depend on the degree to which an undesirable region in a perceptual control space of time headway (THW) and time to collision (TTC) is penetrated (i.e. criticality based on perceptually meaningful cues [4]).

This paper outlines the most important characteristics of the practical type air bag now being developed by Nissan Motor Co., Ltd. It explains the results of various occupant protection tests conducted at 16 to 64 km/h (10 to 40 mph) speeds, and the related problems we have encountered. It further discusses the effects of several type of occupant protection systems installed on small-sized cars and the relationships between those effects and limited crash speeds. An examination and analysis of air bag performance test results is also included. Despite all efforts made, there yet remain several problems to be solved. For example, (a) in high-speed collisions it is difficult to reduce femur load by means of air bag systems alone; (b) passengers such as three-year-old infants and 5th percentile female adults display a tendency toward submarining: (c) when the environmental temperature is extremely low, it is difficult for the air bag to meet the MVSS Occupant Protection Requirements.

By nature, the driver's seat should be designed for work, while the passenger's seat should be built for comfort. This means that the functions of the seats are inherently different. Although many studies have been done on the driver's seat, the design and use of the passenger's seat have received little attention. This study examined a comfortable sitting posture in the passenger's seat. The results obtained have led to the development of two new devices. One device makes it possible for the seat cushion to move upward and forward as the seat tilts backward. The other device allows the upper portion of the seat back to tilt forward from the top of the lower seat back. These devices thus function to provide a comfortable sitting posture. This paper describes the new devices and presents the results of an investigation into a comfortable sitting posture for the occupant of the front passenger's seat.

In Japan, test methods for evaluating the performance of 2-cycle engine oils have been developed separately by each 2-cycle engine manufacturer. The reason for this is that there are are many differences in engine performance and in lubrication methods. Evaluation through bench tests is used as a valid method for screening engine oils prior to field tests. Field tests are conducted eventually as the most reliable test method for evaluating the performance of engine oils. Yamaha Motor, one of the leading Japanese 2-cycle engine manufacturers, developed a “70 min engine test method” in 1963, which can be conducted in a relatively short period of time with good reproducibility. In this paper, several problems regarding Yamaha's 70 min engine test method are discussed.

Nissan's Experimental Safety Vehicle is a small-sized passenger car. "Small-sized" means small in overall dimensions and light weight. Differences between the Japanese 2,500 pound ESV and the 4,000 pound ESV specifications are outlined. This paper discusses small car safety and ESV specifications

The key-points in the diffusion bonding technique of green compacts during sintering, are the material compositions, which should be chosen according to their dimensional change during sintering, and the fitting clearance, which should be maintained in the range of press fit. Applying this technique, we have developed sinter-diffusion bonded idler sprockets for automotive engines by comfirming the bonding strength and torsional fatigue strength. And we also have developed a nondestructive analysis method for assuring the joint strength of idler sprockets in the mass production.

The numerical relations between occupant restraint systems and injury indexes were investigated by multi-parameter optimization of an integrated restraint system model of frontal crash simulations. This paper proposes a method of optimizing restraint systems in two types of test configurations: a 35-mph full overlap crash model and a 40-mph 40%-offset crash model.

Traffic accidents in Japan claim some 10,000 precious lives every year, and there is seemingly no end to the problem. In an effort to overcome this situation, vehicle manufacturers have been pushing ahead with the development of a variety of advanced safety technologies. Joint public- private sector projects related to Intelligent Transport Systems (ITS) are also proceeding vigorously. Most accidents can be attributed to driver error in recognition, judgment or vehicle operation. This paper presents an analysis of driver behavior characteristics in emergency situations that lead to an accident, focusing in particular on operation of the brake pedal. Based on the insights gained so far, we have developed a Brake Assist System with a Preview Function (BAP) designed to prevent accidents by helping drivers with braking actions. Experimental results have confirmed that BAP is effective in reducing the impact speed and the frequency of accidents in emergency situations.

An investigation was made of the relationship between the driving speed at the time of impact and the injury levels suffered in accidents. The results showed that a 5 km/h or more reduction in collision speed tends to mitigate injury severity. Using sensors and brake actuators already in practical use, we have started to research a braking system aimed at reducing the collision speed by at least 5 km/h in rear-end collisions. The system estimates the risk of a collision with the vehicle ahead. If it judges there is a very high possibility of a collision, it applies the brakes.

Traffic accidents in Japan claim some 10,000 precious lives every year, and there is seemingly no end to the problem. In an effort to overcome this situation, vehicle manufacturers have been pushing ahead with the development of a variety of advanced safety technologies. Joint public-private sector projects related to Intelligent Transport Systems (ITS) are also proceeding vigorously. Most accidents can be attributed to driver error in recognition, judgment or vehicle operation. This paper presents an analysis of driver behavior characteristics in emergency situations that lead to an accident, focusing in particular on operation of the brake pedal. Based on the insights gained so far, we have developed a Brake Assist System with a Preview Function (BAP) designed to prevent accidents by helping drivers with braking actions. Experimental results have confirmed that BAP is effective in reducing the impact speed and the frequency of accidents in emergency situations.