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The engine operating point (EOP), which is determined by the engine speed and torque, is an important part of a vehicle's powertrain performance and it impacts FC, available propulsion power, and emissions. Predicting instantaneous EOP in real-time subject to dynamic driver behaviour and environmental conditions is a challenging problem, and in existing literature, engine performance is predicted based on internal powertrain parameters. However, a driver cannot directly influence these internal parameters in real-time and can only accommodate changes in driving behaviour and cabin temperature. It would be beneficial to develop a direct relationship between the vehicle-level parameters that a driver could influence in real-time, and the instantaneous EOP. Such a relationship can be exploited to dynamically optimize engine performance.

A detailed description of the oxidative stability of GM's DEXRON®-VI Factory Fill Automatic Transmission Fluid (ATF) is provided, which can be integrated into a working algorithm to estimate the end of useful oxidative life of the fluid. As described previously, an algorithm to determine the end of useful life of an automatic transmission fluid exists and is composed of two simultaneous counters, one monitoring bulk oxidation and the other monitoring friction degradation [1]. When either the bulk oxidation model or the friction model reach the specified limit, a signal can be triggered to alert the driver that an ATF change is required. The data presented in this report can be used to develop the bulk oxidation model. The bulk oxidation model is built from a large series of bench oxidation tests. These data can also be used independent of a vehicle to show the relative oxidation resistance of this fluid, at various temperatures, compared to other common lubricants.

A driving simulator development project at the Systems Engineering and Technical Process Center (SE/TP) is exploring the role of driving simulation in the vehicle design process. The simulator provides two vehicle mockup testing arenas that support a wide field of view, computer-generated image of the road scene which dynamically responds to driver commands as a function of programmable vehicle model parameters. Two unique aspects of the simulator are the fast 65 ms response time and low incidence rate of simulator induced syndrome (about 5%). Preliminary model validation results and data comparing driver performance in a vehicle vs. the simulator indicate accurate handling response dynamics within the on-center handling region (<0.3g lateral acceleration). Applications have included supporting the development of new steering system concepts, as well as evaluating the usability of vehicle controls and displays.

The dilemma of using a shoulder belt force limiter with a 3-point belt system is selecting a limit load that will balance the reduced risk of significant thoracic injury due to the shoulder belt loading of the chest against the increased risk of significant head injury due to the greater upper torso motion allowed by the shoulder belt load limiter. However, with the use of air bags, this dilemma is more manageable since it only occurs for non-deploy accidents where the risk of significant head injury is low even for the unbelted occupant. A study was done using a validated occupant dynamics model of the Hybrid III dummy to investigate the effects that a prescribed set of shoulder belt force limits had on head and thoracic responses for 48 and 56 km/h barrier simulations with driver air bag deployment and for threshold crash severity simulations with no air bag deployment.

With the increasing presence of the Internet in today's applications, ranging from legacy enterprise systems to handheld devices and home appliances, there is an increasing need for a generic middleware that can enable the interoperability between heterogeneous systems. In the specific case of in-vehicle networks, a generic middleware would enable the vehicle/driver to interact with a diversity of applications, including legacy enterprise systems, other embedded systems and wireless ad-hoc and ubiquitous applications. This paper is the result of an initial investigation into the requirements for such a middleware, and possible directions to be taken for its implementation.

Security is a huge concern in VANETs (Vehicular Ad hoc NETworks) since the information being conveyed may affect life-or-death decisions. One of the security concerns is the Sybil Attack. This attack attempts to create multiple identities to disrupt or control the network. A malicious node utilizing the Sybil Attack in VANETs can disrupt the network in various ways. It can create a large number of Sybil nodes to intervene in message forwarding, potentially causing a massive pileup and great loss of life. A malicious node can also use the Sybil Attack to create illusions of traffic congestions, getting other drivers to take alternate routes and leaving a clear path for the malicious node to its destination. In this paper, we discuss several defense strategies for the Sybil Attack in VANETs.

As the driving population ages, there is a need to understand the accident patterns of older drivers. Previous research has shown that side impact collisions, usually at an intersection, are a serious problem for the older driver in terms of injury outcome. This study compares the frequency of side impact, intersection collisions of different driver age groups using state and national police-reported accident data as well as an in-depth analysis of cases from a fatal accident study. All data reveal that the frequency of intersection crashes increases with driver age. The state and national data show that older drivers have an increase frequency of intersection crashes involving vehicles crossing paths prior to the collision compared to their involvement in all crash types. When taking into account traffic control devices at an intersection, older drivers have the greatest involvement of multiple vehicle crashes at a signed intersection.

This paper presents quantitative effects of windshield veiling glare on the visibility of targets based on a two part research project. The first part involved measurement and modeling of luminance of veiling glare caused by the reflection of different instrument panel materials under range of conditions defined by combination of windshield angle, instrument panel angle, and sun angle. In the second part, the veiling glare model was incorporated in a visibility prediction model based on visual contrast threshold data. A critical visibility condition of a driver approaching a tunnel with the sunlight falling on his windshield and attempting to detect a target inside the tunnel was studied by conducting sensitivity analyses. The sensitivity analysis showed that a 2 ft diameter 10% reflectance target illuminated by 5000 lux of lighting inside a tunnel visibility distances can be seen from 0 to 3,000 feet depending upon driver's age, vehicle design parameters and sun illumination levels.

This study was conducted to develop and validate a multidimensional measure of shift quality as perceived by drivers during kick-down shift events for automatic transmission vehicles. As part of the first study, a survey was conducted among common drivers to identify primary factors used to describe subjective gear-shifting qualities. A factor analysis on the survey data revealed four semantic subdimensions. These subdimensions include responsiveness, smoothness, unperceivable, and strength. Based on the four descriptive terms, a measure with semantic scales on each subdimension was developed and used in an experiment as the second study. Twelve participants drove and evaluated five vehicles with different gear shifting patterns. Participants were asked to make kick-down events with two different driving intentions (mild vs. sporty) across three different speeds on actual roadway (local streets and highway).

It is well understood that driver's steering input strongly affects lateral vehicle dynamics and excessive steering command may result in unstable vehicle motion. In a certain driving condition, it is possible for a skilled driver to prevent vehicle rollover with better perceptive capability of judging conditions and responding faster with smooth compensatory actions. This paper investigates the possibility of using active steering and wheel torque control to assist drivers in avoiding vehicle rollovers in emergency situations. The effectiveness of steering control alone and combination of steering/wheel torque control in recovery from unstable vehicle roll condition was demonstrated through simulation of both low and high vehicle speeds.

With recent advances in microprocessors and data storage technologies, vehicle users can now bring or access large amounts of data in vehicles for purposes such as communication (e.g. e-mail, phone books), entertainment (e.g. music and video files), browsing and searching for information (e.g. on-board computers and internet). The challenge for the vehicle designer is how to design data displays and retrieval methods to allow data search and manipulation tasks by managing driver workload at safe acceptable levels. This paper presents a data retrieval menu system developed to assess levels of screens (depth of menu) that may be needed to select required information when a vehicle is equipped with the capability to access audio files, cell phone, PDA, e-mail and “On-star” type functions.

Fatal crash circumstances for 48 belted female drivers were studied in-depth and compared to those of 83 belted male drivers in a similar population of vehicles. Women had a higher incidence of crashes on slippery roads, during lane changes and passing maneuvers than men who had a higher rate of aggressive driving and speed related crashes (χ2 = 10.47, p < 0.001). Driver-side damage was significantly more frequent in female than male crashes (χ2 = 5.74, p < 0.025) and women had a higher fraction of side impacts (45.9% v 31.4%) and crashes during daylight (87.0% v 72.3%, χ2 = 3.65, p < 0.05) than men. Women also had a higher fraction of potentially avoidable crashes than men (57.5% v 39.0%) and a lower involvement related to aggressive driving (10.6% v 25.6%). These differences were statistically significant (χ2 = 5.41, p < 0.025).

This paper presents results of a study conducted to determine differences in older (over age 55) and younger (under age 35), male and female drivers while entering and exiting vehicles with three different body styles - namely, a large sedan, a minivan and a full-size pick-up truck. Thirty-six drivers (males and females, ages 25 to 89 years) who participated in this study were first measured for their anthropometric, strength and body flexibility measures relevant to the entry/exit tasks. They were asked to first get in each vehicle and adjust their preferred seating position. Then, they were asked to get in the vehicle and their entry time was measured. Their entry maneuver was also video taped and they were asked to rate the level of ease/difficulty (using a 5-point scale) in entering. Similar procedure and measurements were conducted during their exit from each vehicle.

As intelligent automated vehicle technologies evolve, there is a greater need to understand and define the role of the human user, whether completely hands-off (L5) or partly hands-on. At all levels of automation, the human occupant may feel anxious or ill-at-ease. This may reflect as higher stress/workload. The study in this paper further refines how perceived workload may be determined based on occupant physiological measures. Because of great variation in individual personalities, age, driving experiences, gender, etc., a generic model applicable to all could not be developed. Rather, individual workload models that used physiological and vehicle measures were developed.

This paper describes a research project currently in-progress to develop a parametric model of a vehicle for use in early design stages of a new vehicle program. The model requires key input parameters to define the kind of new vehicle to be designed — in terms of details such as its intended driver/user population, vehicle type (e.g. 2-box, 3-box designs), and some key exterior and interior dimensions related to its size and proportions. The model computes and graphically displays interior package, ergonomics zones for driver controls and displays, and field of views through window openings. It also allows importing or inputting and superimposing and manipulating exterior surfaces created by a designer to assess compatibility between the interior occupant package and the vehicle exterior.

This paper presents results of a three-phase research project aimed at understanding how future automotive interior materials should be selected or designed to satisfy the needs of the customers. The first project phase involved development of 22 five-point semantic differential scales to measure visual, visual-tactile, and evaluative characteristics of the materials. Some examples of the adjective pairs used to create the semantic differential scales to measure the perceptual characteristics of the material are: a) Visual: Light vs. Dark, Flat vs. Shiny, etc., b) Visual-Tactile: Smooth vs. Rough, Slippery vs. Sticky, Compressive vs. Non-Compressive, Textured vs. Non-Textured, etc., c) Evaluative (overall perception): Dislike vs. Like, Fake vs. Genuine, Cheap vs. Expensive, etc. In the second phase, 12 younger and 12 older drivers were asked to evaluate a number of different automotive interior materials by using the 22 semantic differential scales.

Truck driver shin-knee and stomach postion tools have been developed to describe where certain percentages of truck drivers position there knees and stomachs in various workspace arrangements. Separate equations describe the accommodation level for driver populations with male to female ratios of 50/50, 75/25, and a range from 90/10 to 95/5. These equations can be used as a design tool to locate the curves in vehicle space to describe the region behind which the given populations shin-knees, and stomachs would be located. Equations and curves are provided for both the left leg, which operates the clutch, and the right leg, which operates the accelerator.

Truck driver eye and head position tools have been developed to describe where certain percentages of truck drivers position there eyes and heads in various workspace arrangements. Separate equations describe the accommodation level for driver populations with male to female ratios of 50/50, 75/25, and a range from 90/10 to 95/5. These equations can be used as a design tool to locate the curves in vehicle space to describe the region behind which the given populations eyes and heads would be located. Equations and curves are provided for both the drivers eye and head in the side view. It has become increasingly apparent that there is a need for improved methods of accommodating truck drivers in heavy truck cab design. Currently, practices used in the automobile industry for passenger car design are utilized for the design of heavy trucks. These practices.

Many traffic collisions are the result of the driver's failure to notice the other vehicle. It is often cited in police reports that the driver "looked but did not see.'' The purpose of Daytime Running Lights (DRLs) is to increase the visual contrast of DRL-equipped vehicles. Visual contrast, which is the difference in brightness between two areas, is an important characteristic enabling a driver to detect objects. This paper begins with a brief regulatory history of DRLs in the U.S. and how General Motors Corporation (GM) introduced DRL-equipped vehicles. It also describes a DRL effectiveness study conducted by Exponent Failure Analysis Associates of San Francisco for General Motors Corporation. The study compared the collision rates of specific General Motors Corporation, Saab, Volvo and Volkswagen vehicles before and immediately after the introduction of DRLs. Since DRLs are not visible from behind a vehicle, rear-end collisions were not included in the study.

The causes for 131 fatal crashes of lap-shoulder belted occupants were analyzed for crash causation and avoidance opportunities. Fourteen crash scenarios were determined to depict the situation and circumstance of the accidents. Each scenario is discussed in relation to driver age, actions, behavior, errors and aggressiveness, as well as crash type and other factors influencing the crash. Nearly a third of crashes involved a rapid, unpredictable onset by reckless action or mistake of another driver. The remainder were caused by the driver of the case-vehicle. Some were single vehicle crashes primarily related to excessive speed, aggressive driving, and drifting out of lane. The others were multi-vehicle crashes due primarily to inadvertent errors. The most common errors were right-of-way violations at an intersection, loss of control on wet roads, impact of a stationary vehicle, and lane changing errors.