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The goal of this interview analysis was to explore and document the perceptions of two unique lane centering systems (S90’s Pilot Assist and CT6’s Super Cruise). Both systems offer a similar type of functionality (adaptive cruise control and lane centering), but have significantly different design philosophies and HMI (Human-Machine Interface) implementations. Twenty-four drivers drove one of the two vehicle models for a month as part of a field operational test (FOT) study. Upon vehicle return, drivers took part in a 60-minute semi-structured interview covering their perceptions of the vehicle’s various advanced driver-assistance systems (ADAS). Transcripts of the interviews were coded by two researchers, who tagged each statement with relevant system and perception code labels. For analysis, the perception codes were grouped into larger thematic bins of safety, comfort, driver attention, and system performance.

This paper reviews the relevant literature on the effects of sulfated ash, phosphorus, and sulfur on DPF, LNT, and SCR catalysts. Exhaust backpressure increase due to DPF ash accumulation, as well as the rate at which ash is consumed from the sump, were the most studied lubricant-derived DPF effects. Based on several studies, a doubling of backpressure can be estimated to occur within 270,000 to 490,000 km when using a 1.0% sulfated ash oil. Postmortem DPF analysis and exhaust gas measurements revealed that approximately 35% to 65% less ash was lost from the sump than was expected based on bulk oil consumption estimates. Despite significant effects from lubricant sulfur and phosphorus, loss of LNT NOX reduction efficiency is dominated by fuel sulfur effects. Phosphorus has been determined to have a mild poisoning effect on SCR catalysts. The extent of the effect that lubricant phosphorus and sulfur have on DOCs remains unclear, however, it appears to be minor.

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.

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

Most of the side impact air bag systems in the current market are designed to protect the thorax area only. The new Head and Thorax SRS Side Impact Air Bag system, which Nissan recently introduced into the market, was designed to help provide additional protection for the head in certain side impacts. The system may help protect occupant head contacts when the vehicle collides into a tree, or the high hood of a large striking vehicle. This paper introduces the additional features and function of the new Head and Thorax SRS Side Impact Air Bag system, and some evaluation results in laboratory testing.

Natural speech contains a wide variety of expressions, making it much more difficult to recognize than specified verbal commands. We have developed a method using a language model template to generate language models capable of recognizing manifold expressions. This template method is designed on the basis of the modification structure of keywords. The evaluation results for a language model generated with this method showed that it allowed 630,000 command patterns with a high recognition rate of 96%. The results also revealed that the processing speed and memory used for speech recognition with this language model were at a practical level.

On-board voice-interaction systems such as a voice-activated system or a text -to-speech (TTS) system enable drivers to operate devices or to obtain desired information without relying on visual processes. These systems are aimed to reduce the driver's workload, but there is a concern about their possible effect on mental distraction. This paper describes driving simulator tests that were conducted to examine the potential influence of such systems on driver's mental distraction. The results obtained for all of the indices show that the mental distraction level when operating a voice-activated system is significantly lower than that of a traditional manually operated system.

CFRP (Carbon Fiber Reinforced Plastic) materials have been extensively used in racing cars because of its high stiffness and lightweight. Recently, car crash safety is becoming increasingly important even for racing cars. CFRP has also a merit on crash safety because it offers the freedom to set the material characteristics where needed and the needless of considering remaining length after the impact. In this analysis, a multi-layered shell material is applied to reproduce the crash characteristics of the CFRP structure. Fundamental crash test data of simple specimens are used to verify the material characteristics of CFRP, and applied to the Crash-Box of a Nissan GT500 racing car. The simulation showed good correlation with the actual test, and the final design was based on these analyses without the need of repeating impact tests.

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.

Flow velocity distributions in the passenger compartment were measured from visualized images of particle flow paths obtained with a full-scale model. The flow paths were visualized using an approach that combined a particle tracing method with a pulse-laser light technique. Air was used as the fluid medium with the full-scale passenger compartment model and water was used as the fluid medium with a one-fourth scale model. A comparison of the results obtained with the two models confirmed that there was good agreement between the flow velocity distributions. Using the full-scale model, measurements were also made of the flow velocity distributions when two dummies were placed in the front-seats.

Evaluations of dummy injury readings obtained in regulatory crash tests and new car assessment program tests provide indices for the development of crash safety performance in the process of developing new vehicles. Based on these indices, vehicle body structures and occupant restraint systems are designed to meet the required occupant injury criteria. There are many types of regulatory tests and new car assessment program tests that are conducted to evaluate vehicle safety performance in side impacts. Factoring all of the multiple test configurations into the development of new vehicles requires advanced design capabilities based on a good understanding of the mechanisms producing dummy injury readings. In recent years, advances in computer-aided engineering (CAE) tools and computer processing power have made it possible to run simulations of occupant restraint systems such as side airbags and seatbelts.

This paper presents the results of a study of how people interacted with a production voice-command based interface while driving on public roadways. Tasks included phone contact calling, full address destination entry, and point-of-interest (POI) selection. Baseline driving and driving while engaging in multiple-levels of an auditory-vocal cognitive reference task and manual radio tuning were used as comparison points. Measures included self-reported workload, task performance, physiological arousal, glance behavior, and vehicle control for an analysis sample of 48 participants (gender balanced across ages 21-68). Task analysis and glance measures confirm earlier findings that voice-command interfaces do not always allow the driver to keep their hands on the wheel and eyes on the road, as some assume.

This paper describes the HMI, navigation and telematics systems developed specifically for the Nissan LEAF electric vehicle to dispel drivers' anxieties about operating an EV. Drivers of EVs will need to understand various new kinds of information about the vehicle's operational status that differ from conventional gasoline-engine vehicles. Additionally, owing to the current driving range of EVs and limited availability of charging stations, drivers will want to know acccurate the remaining driving range, amount of power and the latest information about charging station locations. It will also be important to ensure that people unfamiliar with EVs will be able to operate them easily as rental cars or in car-sharing systems without experiencing any inconvenience.

The progress of computer technology and CAE methodology makes it possible to simulate dummy injury readings in vehicle crash simulations. Dummy neck injuries are generally more difficult to simulate than injuries to other regions such as the head or chest. Accordingly, improving the accuracy of dummy neck injury data is a major concern in frontal occupant safety simulations. This paper describes the use of an advanced airbag modeling methodology to improve the accuracy of dummy neck injury readings. First, the following items incorporated in the advanced airbag model are explained. (1) The Finite Point Method (FPM) is used to simulate the flow of gas. (2) A folding model is applied to simulate the folded condition. (3) The fabric material properties used in the simulation take into account anisotropy in the fiber directions and the nonlinear, hysteresis characteristics of stiffness.

A side impact is one of the severest crash configurations among real-world accidents. In the US market, even though most vehicles have achieved top ratings in crash performance assessment programs in recent years, there has hardly been any sign of a decline in side-impact fatalities for the last few years, according to statistics retrieved from the National Highway Traffic Safety Administration’s Fatality Analysis Reporting System. In response to this trend, the Insurance Institute for Highway Safety (IIHS) is planning to introduce a new test protocol for side impact assessment. One of the points to be clarified in current side impact tests is whether the present side moving deformable barrier (MDB), which includes the barrier face and cart, faithfully reproduces a real-world car-to-car crash.

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]).

A technique has been developed to measure the desorption and subsequent oxidation of fuel in the oil layer by spiking the oil with liquid fuel and firing the engine on gaseous fuel or motoring with air. Experiments suggest that fuel desorption is not diffusion limited above 50 °C and indicated that approximately two to four percent of the cylinder oil layer is fresh oil from the sump. The increase in hydrocarbon emissions is of the order of 100 ppmC1 per 1% liquid fuel introduced into the fresh oil in a methane fired engine at mid-speed and light load conditions. Calculations indicate that fuel desorbing from oil is much more likely to produce hydrocarbon emissions than fuel emerging from crevices.

Laser induced fluorescence (LIF) is a useful method for visualizing the distribution of the air-fuel ratio in the combustion chamber. The way this method is applied mainly depends on the fluorescent tracer used, such as biacetyl, toluene, various aldehydes, fluoranthene or diethylketone, among others. Gasoline strongly absorbs light in the UV region, for example, at the 248-nm wavelength of broadband KrF excimer laser radiation. Therefore, when using this type of laser, iso-octane is employed as the fuel because it is transparent to 248-nm UV light. However, since the distillation curves of iso-octane and gasoline are different, it can be expected that their vaporization characteristics in the intake port and cylinder would also be different. The aim of this study was to find a better fuel for use with LIF at a broadband wavelength of 248 nm. Three tasks were undertaken in this study.

This paper presents a method for optimizing occupant restraint system parameters in vehicle frontal crashes. Simulation models incorporating restraint systems and dummies are used for predicting injury indexes. A full-scale survey of all of the design parameters related to the injury indexes would require a vast number of simulations. Therefore, the Design of Experiments (DOE) method involving a minimum number of experiments is more realistic. However, dummy behavior often shows discontinuity if the dummy comes in contact with the steering wheel, so it is not predicted well with usual DOE methods. This paper shows how to incorporate such discontinuity in a DOE study and how to optimize the restraint system parameters to reduce occupant injury indexes. It also discusses the feasibility of this method for integrated optimization of 50th percentile and 5th percentile dummies.

An automatic, falling, occupant-protecting net is being developed for spreading in front of automobile occupants in the time interval between vehicle impact and occupant collision. The device is designed to counteract forward body acceleration and minimize head, neck, and chest injuries. This device was investigated by sled and barrier tests using anthropomorphic dummies. Significant improvements in occupant kinematics and remarkable reduction in head and chest impact force has been observed. Some problems such as whiplash injury await solution but continuing investigation of proposed measures of correction show that they are not insurmountable.