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We examined relative effectiveness of heads-up visual displays for lane departure warning (LDW) 39 younger to middle aged drivers (25-50, mean = 35 years) and 37 older drivers (66-87, mean = 77 years). The LDW included yellow “advisory” visuals in the center screen when the driver started drifting toward the adjacent lane. The visuals turned into red “imminent” when the tires overlapped with the lane markers. The LDW was turned off if the driver activated the turn signal. The visuals could be easily segregated from the background scene, making them salient but not disruptive to the driver’s forward field of view. The visuals were placed adjacent to the left and right lane markers in the lower half of the center screen.

The mechanics of on-road, friction-induced rollovers were studied with the aid of a three-dimensional computer code specifically derived for this purpose. Motions of the wheels, vehicle body, occupant torso, and head were computed. Kane's method was utilized to develop the dynamic equations of motion in closed form. On-road rollover kinematics were compared to a dolly-type rollover at lesser initial speed, but generating a similar roll rotation rate. The simulated on-road rollover created a roof impact on the leading (driver's) side, while the dolly rollover simulation created a trailing-side roof impact. No head-to-roof contacts were predicted in either simulation. The first roof contact during the dolly-type roll generated greater neck loads in lateral bending than the on-road rollover. This work is considered to be the first step in developing a combined vehicle and occupant computational model for studying injury potential during rollovers.

Advanced Driver Assistive System (ADAS) technologies have been introduced as the automotive industry moves towards autonomous driving. One ADAS technology with the potential for substantial safety benefits is forward collision warning and mitigation (FCWM), which is designed to warn drivers of imminent front-end collisions, potentiate driver braking responses, and apply the vehicle's brakes autonomously. Although the proliferation of FCWM technologies can, in many ways, mitigate the necessity of a timely braking response by a driver in an emergency situation, how these systems affect a driver's overall ability to safely, efficiently, and comfortably operate a motor vehicle remains unclear. Exponent conducted a closed-course evaluation of drivers' reactions to an imminent forward collision event while driving an FCWM-equipped vehicle, either with or without a secondary task administered through a hands-free cell phone.

Engineering Dynamics Corporation (EDC) recently updated the Human, Vehicle, Environment (HVE) software program to enable modeling of passenger cars and light trucks towing trailers. This paper reports on a comparison between the HVE EDSMAC4 collision module of the 3-dimensional computer simulation program and instrumented crash tests, in which one vehicle in each test was a pickup truck pulling a trailer. Use of the EDSMAC4 trailer model was found to provide better correlation between the simulation and test damage profiles, rest positions, vehicle trajectories, velocities, and Delta-V. It was also determined that the NHTSA-derived stiffness coefficients are sensitive to the impact configuration and depending on the impact configuration, it may be necessary to refine the coefficients according to the configuration.

Inadvertent vehicle movement incidents, in which a vehicle rolls away after the driver has exited, may occur in automatic transmission vehicles as a result of environmental, vehicular, and/or driver factors. Some explanations have focused on claimed potential malfunctions or design flaws in the vehicle's console shift mechanism or in the automatic transmission itself. However, growing evidence suggests that driver errors unrelated to vehicle design may in fact be the primary cause of many inadvertent vehicle movement incidents. The present research extends previous work on driver gear-shifting behaviors and vehicle egress by conducting more in-depth analyses of data collected by Harley et al. (2008).

In testing to determine the yaw oscillation response of a vehicle-trailer combination, the vehicle combination is driven in a straight line, at a specified speed; then a rapid, fixed-amplitude, short-duration pulse is applied to the steering wheel, while maintaining a constant speed. These requirements often result in multiple test runs to ensure an acceptable minimum variability in the damping ratio estimate for the vehicle-trailer combination. This paper investigates techniques for relieving the demands placed on the driver and for acquiring and processing the data required for analysis from this test. The testing used two different vehicle-trailer combinations, two different drivers, and an Automated Steering Controller (ASC). Damping ratio estimate comparisons were made between drivers, drivers and the ASC, transducers, data filtering, and calculation methods.

Field accident data have demonstrated that occupant ejection during vehicle rollover is associated with a high risk of serious and fatal injury. Although it has been demonstrated that seat belt use is highly effective in preventing occupant ejections, it has been argued that occupant containment during rollover can be accomplished with the use of laminated side glazing. This study was conducted to evaluate the retention characteristics of production laminated side windows. The current vehicle fleet was surveyed for vehicles equipped with production laminated side glass. The survey examined relevant window system parameters including glass retention system, glass configuration, and window geometry. A representative subset of five front door systems from several manufacturers was chosen for further evaluation. In addition, one legacy rear door system with laminated glass was included for comparison.

This paper describes an investigation that seeks to understand how rollovers occur in real-world crashes, both by studying real world crashes and by analyzing vehicle handling tests to gain insights into potential mechanisms of pre-crash loss of control. In particular, this study focuses on one type of rollover, namely single-vehicle rollovers that follow a pattern of the vehicle first leaving the roadway and then returning to the roadway typically out-of-control. Aims of this study included the following: To describe the frequency and characteristics of single-vehicle rollovers involving an off-roadway excursion followed by a complete, if only temporary return to the roadway. To the extent possible, given available data, to assess the nature and consequences of driver inputs during the crash sequence. To define characteristics of crash scenarios which include a substantial proportion of this subset of single-vehicle rollovers.

Construction of a transient model for a Class 8 tractor-trailer negotiating mountain terrain is presented. Four basic brake models for free and forced cooling (GSRS, UMTRI, Limpert, and HVE Brake Designer®) are converted to consistent units. The units have been reduced to those accepted variables in the thermodynamic/heat transfer literature (hc, A, cp, M), thereby facilitating model comparison and coefficient selection from the published literature. The data has been compared to real test published data. The effect of varying the desired vehicle speed, vehicle weight, number of adjusted brakes, and slope magnitude on brake drum temperatures is explored.

Testing techniques for creating rollovers have been a subject of much study and discussion, although previous work has concentrated on creating a repeatable laboratory test for evaluating and comparing vehicle designs. The two testing methodologies presented here address creating rollover tests that closely mimic a specific accident scenario, and are useful in accident reconstruction and evaluation of vehicle performance in specific situations. In order to be able to recreate accidents on off-road terrain, a test fixture called the Roller Coaster Dolly (RCD) was developed. With the RCD a vehicle can be released at speed onto flat or sloping terrain with any desired initial roll, pitch and yaw angle. This can be used to create rollover collisions from the trip stage on, including scenarios such as furrow trip on an inclined road edge.