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There have been many studies regarding the stability of vehicles following a sudden air loss event in a tire. Previous works have included literature reviews, full-scale vehicle testing, and computer modeling analyses. Some works have validated physics-based computer vehicle simulation models for passenger vehicles and other works have validated models for heavy commercial vehicles. This work describes a study wherein a validated vehicle dynamics computer model has been applied to extrapolate results to higher event speeds that are consistent with travel speeds on contemporary North American highways. This work applies previously validated vehicle dynamics models to study the stability of a five-axle commercial tractor-semitrailer vehicle following a sudden air loss event for a steer axle tire. Further, the work endeavors to understand the analytical tire model for tires that experience a sudden air loss.

Determining impact speeds is an important factor in any accident reconstruction. Event data recorders are now commonplace in on-road vehicles and provide an added tool for the accident reconstructionist. However, in low-speed collisions where impact severity is often important, event data recorders fail to record data as the minimum threshold for impact severity sometimes is not met. Alternatively, damage-based methods may be ineffective in quantifying the severity of the impact due to a lack of defined vehicle crush damage. These types of scenarios oftentimes present themselves as a bullet vehicle in the beginning processes of accelerating from a stop or when a stopped target vehicle is rear-ended from behind by the bullet vehicle.

Recent studies evaluating motorcycle lean angle have compared theoretical lean angle equations with real-world-tested motorcycle lean angles. These studies have considered several factors affecting lean angle, including the simplified assumptions made when calculating theoretical lean angles, the speed of the motorcycle around a curve, and the geometry of the roadway/curve. This study further evaluates motorcycle lean angle as a function of speed, but primarily focuses on the effects of different travel paths selected by the rider around the same constant radius curve. The testing incorporates nine passes around the same curve traveling three different paths at three different speeds. The real-world-tested lean angles were compared to the predicted calculated lean angles for each tested travel path and speed.

There have been limited empirical studies regarding the dynamics of a motorcycle and rider as a motorcycle traverses a roadway irregularity such as a pothole or depression, or a traffic calming device (TCD) such as a speed bump. This study seeks to establish qualitative analysis of the success of motorcycles traversing various roadway irregularities/TCDs as well as quantitatively analyzing accelerations to the motorcycle at varying speeds and lean angles. Further analysis is conducted comparing the accelerations experienced in scenarios where the suspension of the motorcycle experiences extension followed by compression, as is the case when encountering a pothole or depression, as well as scenarios where the suspension of the motorcycle experiences compression followed by extension, as is the case when encountering a TCD.

Currently, several cost-per-mile calculators exist that can provide estimates of acquisition and operating costs for consumers and fleets. However, these calculators are limited in their ability to determine the difference in cost per mile for consumer versus fleet ownership, to calculate the costs beyond one ownership period, to show the sensitivity of the cost per mile to the annual vehicle miles traveled (VMT), and to estimate future increases in operating and ownership costs. Oftentimes, these tools apply a constant percentage increase over the time period of vehicle operation, or in some cases, no increase in direct costs at all over time. A more accurate cost-per-mile calculator has been developed that allows the user to analyze these costs for both consumers and fleets. Operating costs included in the calculation tool include fuel, maintenance, tires, and repairs; ownership costs include insurance, registration, taxes and fees, depreciation, financing, and tax credits.

This study was conducted to compare vehicle speed change and acceleration data from full scale testing to results generated by the Simulation Model Non-linear (SIMON) vehicle dynamic simulation model (version 2.0) within the Human Vehicle Environment (HVE) software. The study also sought to expand the body of existing curb impact tests and compare the present results to data from published literature. The results of the full scale testing of a 1996 Dodge Ram 1500 pickup are presented. Instrumented tests were performed at speeds up to approximately 6.7 m/s (15.0 mph) and at approach angles of 90° and 45°. SIMON was used to simulate the full scale testing conducted by the authors. The simulation results, including primarily vehicle speed change (delta-v), and accelerations are compared to the results of full scale testing. The appropriate method for modeling curb profile within SIMON version 2.0 was studied and is presented in this paper.

Low speed collinear collisions have received some attention in the past in published technical literature. Underrepresented are full-scale instrumented tests utilizing vehicles equipped with foam core bumpers and closing speeds greater than 2.2 meters per second (m/s). Systematic testing was designed to obtain data in collisions between vehicles with similar and mixed bumper structures. Testing was performed at closing speeds ranging from 0.8 to 5.4 m/s. Following each test, vehicle bumper and other damage was documented. Data from the 30 tests for each category of bumper and mixed categories were analyzed to identify the test speed, load magnitude, velocity change, duration of impact and coefficient of restitution. In addition, the energy absorption characteristics and damage thresholds of the various types of bumper systems were obtained.