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This paper investigates the crashworthiness of structural composite components in frontal and side crash tests. In addition, the safety benefits of composites applications in future lighter vehicles are studied. The methodology of the research includes two steps: (1) developing a light-weight vehicle based on a current finite element (FE) vehicle using advanced plastics and composites, and (2) evaluating the crashworthiness of the light-weighted vehicle by frontal and side New Car Assessment Program (NCAP) test simulations. An FE model of a 2007 Chevrolet Silverado, which is a body-on-frame pickup truck, was selected as the baseline vehicle for light-weighting. By light-weighting components in the Silverado, the vehicle weight was reduced 19%. As a result, the content of plastics and composite in the light-weighted vehicle was 23.6% of the total weight of the light-weight vehicle.

The objective of this research is to understand the crashworthiness performance of composite inserts in vehicle structure and to improve the numerical model of steel-composite combined structure for providing better prediction in the design process of composite inserts. A simplified steel-composite combined beam structure is used for three-point bending tests. Epoxy-based structural foam and 33% short glass fiber reinforced nylon composite insert are considered as composite fillers in empty sections of double hat-type steel beam structure. Four cases based on the different combination of composite materials are considered. In the series of physical three-point bending tests, the force-displacement (F-D) curves and material behaviors are investigated. The test results show that the composite insert greatly contributes to improve the crashworthiness of beam structure as well as to reduce the vehicle weight.

An active torque control steering system is developed and implemented in a car simulator. The simulator has a comprehensive and accurate full vehicle dynamics and road/environment models. A simple model of the driving simulator’s vehicle was developed and a PID controller, which uses the vehicle’s yaw angle, and position, was designed to control vehicle steering torque. The controller is then integrated with the driving simulator program, emulating the real world conditions. The developed system was tested in various obstacle avoidance and lane change scenarios in the car simulator, and the vehicle was able to avoid the stationary obstacles autonomously.

Various numerical models of anthropomorphic test device (ATD) have been developed over the last decade ranging from rigid body models to deformable models. Today, these models have become an integral part of development and optimization of vehicle restraints. The objective of this work is to further advance transportation safety by providing easy access to robust finite element (FE) dummy models to researchers worldwide. To this end, the National Crash Analysis Centre (NCAC) is developing a suite of highly detailed public domain FE models of the crash test dummies. This paper presents the modeling and validation status of the most commonly used crash test dummy in regulatory and consumer metric testing, the Hybrid III 50th percentile crash test dummy. Systematic modeling and validation procedures are established and adopted to ensure the accuracy, efficiency, robustness, and ease of use of the models.

Vehicle stiffness is one of the three major factors in vehicle to vehicle compatibility in a frontal crash; the other two factors are vehicle mass and frontal geometry. Vehicle to vehicle compatibility in turn is an increasingly important topic due to the rapid change in the size and characteristics of the automotive fleet, particularly the increase of the percentage of trucks and SUVs. Due to the non-linear nature of the mechanics of vehicle structure, frontal stiffness is not a properly defined metric. This research is aimed at developing a well defined method to quantify frontal stiffness for vehicle-to-vehicle crash compatibility. The method to be developed should predict crash outcome and controlling the defined metric should improve the crash outcome. The criterion that is used to judge the aggressivity of a vehicle in this method is the amount of deformation caused to the vulnerable vehicles when crashed with the subject vehicle.

According to the Fatality Analysis Reporting System (FARS, 1995-2004), over 20 percent of fatal frontal crashes are into fixed narrow objects such as trees and utility poles in real world crashes. The Insurance Institute for Highway Safety (IIHS) has studied the frontal pole impact test since 2005, conducting a series of tests using passenger cars that are rated “Good” from the IIHS frontal offset test. Passenger cars were impacted into a 10-inch-diameter rigid pole at 64-kph. The alignment of the pole along the centerline of the vehicles in frontal impact was varied to study the influence on dummy injury metrics. This paper evaluates the frontal center pole test conducted by the IIHS. The IIHS tests 21 crashes impacted by the rigid pole using 5 vehicle models with two dummies in the front seat. Intrusions and dummy readings were reviewed according to the frontal offset rating criteria of the IIHS for structural performance and injury measurement.

To date, anthropomorphic test devices (ATDs) have not been designed with consideration for human motion in far-side impacts. Previous tests with a cadaver and a BioSID dummy at the Medical College of Wisconsin confirmed that the dummy does not suitably model the human motion. To further evaluate different ATDs in far-side crashes, MAthematical DYnamic MOdeling (MADYMO) was employed. The modeling showed that the motion of a Hybrid III, BioSID, EuroSid1, EuroSID2, or SID2s did not accurately reflect the motion of a human cadaver under the same impact configurations as the cadaver test. The MADYMO human facet model was found to closely reproduce the kinematics of the cadaver test. The effect of varying console designs on occupant kinematics is presented in this paper. The human facet model appears to be a good interim tool for the evaluation of countermeasures in far-side crashes.

According to National Highway Traffic Safety Administration (NHTSA) speed-related traffic fatalities accounted for 31% of total fatalities on U.S. roadways in 2003. Traditional speed control methods suffer from significant shortcomings. Adaptation (ISA) systems hold the promise of safer roadways through improving driver compliance with speed limits. This paper describes the development of a new multi-modal speed adaptation system to be tested in the CISR car-driving simulator. The system is capable of adapting to the driver's driving style and provides appropriate warning for over speeding based on the vehicle speed, speed limit, driver individual preferences, and risk factor. A hierarchical manager module determines the warning strategy. The adequate warning strategy is specific to driving situations and individual characteristics. Modes of warnings being considered include VISUAL, and HAPTIC.