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Modern passenger cars are being equipped with advanced driver assistance systems such as lane departure warning, collision avoidance systems, adaptive cruise control, etc. Testing for operation and effectiveness of these warning systems involves interaction between vehicles. While dealing with multiple moving vehicles, obtaining discriminatory results is difficult due to the difficulty in minimizing variations in vehicle separation and other parameters. This paper describes test strategies involving an automated test driver interacting with another moving vehicle. The autonomous vehicle controls its state (including position and speed) with respect to the target vehicle. Choreographed maneuvers such as chasing and overtaking can be performed with high accuracy and repeatability that even professional drivers have difficulty achieving. The system is also demonstrated to be usable in crash testing.

There have been a number of papers written about the dynamic effects of low speed front to rear impacts between motor vehicles during the last several years. This has been an important issue in the field of accident analysis and reconstruction because of the frequency with which the accidents occur and the costs of injuries allegedly associated with them. Sideswipe impacts are another, often minor, type of motor vehicle impact that generate a significant number of injury claims. These impacts are difficult to analyze for a number of reasons. First, there have been very few studies in the literature describing the specific dynamic effects of minor sideswipe impacts on the struck vehicles and their occupants. Those that have been performed have focused on the impact of two passenger cars.

The severity of an impact in terms of the acceleration in the occupant compartment is dependent not only on the change in vehicle velocity, but also the time for the change in velocity to occur. These depend on the geometry and stiffness of both the striking vehicle and struck object. In narrow-object frontal impacts, impact location can affect the shape and duration of the acceleration pulse that reaches the occupant compartment. In this paper, the frontal impact response of a full-sized pickup to 10 mile per hour and 20 mile per hour pole impacts at the centerline and at a location nearer the frame rails is compared using the acceleration pulse shape, the average acceleration in the occupant compartment, and the residual crush. A bilinear curve relating impact speed to residual crush is developed.

The shape of an acceleration pulse in an impact is not only affected by the change in velocity, but also by the geometry and stiffness of the both the striking vehicle and the struck object. In this paper, the frontal crash performance of a full-size pickup is studied through a series of impact tests with a rigid pole and with a flat barrier. Each rigid pole test is conducted at one of four locations across the front of the vehicle and at impact speeds of 10 mph, 20 mph, or 30 mph. The flat barrier tests are conducted at 10 mph, 15 mph, 20 mph, and 30 mph. The vehicle crush and acceleration pulses resulting from the pole tests are compared to those resulting from the barrier tests. The severity of pole impacts and the severity of flat barrier impacts are compared based on peak accelerations and pulse durations of the occupant compartment.

This paper presents an evaluation of a vehicle dynamics model intended to be used for the National Advanced Driving Simulator (NADS). Dynamic validation for high performance simulation is not merely a comparison between experimental and simulation plots. It involves strong insight of vehicle's subsystems mechanics, limitations of the mathematical formulations, and experimental predictions. Lateral, longitudinal, and ride dynamics are evaluated using field test data, and analytical diagnostics. The evaluation includes linear and non-linear range of vehicle dynamics response.

There is currently a considerable effort being devoted to the development of anthropomorphic test devices for the measurement of thoracic side impact response. Both the SID and EUROSID have been proposed as viable candidates for this test device. In addition, the thorax of the three year old Fart 572 has been shown to be useful in simulating side impact while used in the frontal orientation. This apparent anomaly suggests that the intuitive differences between the frontal and side geometries of the thorax may not be significant. To date, all useable thoracic models have been unidirectional. For the most part, these have been frontal models. This paper discusses some of the difficulties inherent in the development of a two dimensional thoracic model and ways these difficulties can be addressed. Based on these considerations, a single thoracic impact model is proposed for simulation of both frontal and lateral impact without adjustment of model parameters for impact direction.

The Federal Side Impact Test Procedure prescribed by FMVSS 214, simulates a central, orthogonal intersection collision between two moving vehicles by impacting the side of the stationary test vehicle with a moving test buck in a crabbed configuration. While the pre- and post-impact speeds of the vehicles involved in an accident can not be duplicated using this method, closing speeds, vehicle damage, vehicle speed changes and vehicle accelerations can be duplicated. These are the important parameters for the examination of vehicle restraint system performance and the prediction of occupant injury. The acceptability of this method of testing is not as obvious for the reconstruction of accidents where the impact is non-central, or the angle of impact is not orthogonal. This paper will examine the use of crash testing with a single moving vehicle to simulate oblique or non-central collisions between two moving vehicles.

The purpose of this paper is to give a description of using the new type Suspension Parameter Measurement Device. The design philosophy and specifications are elaborated on in another SAE paper entitled “Design of a New-Type Suspension Parameter Measurement Device”. The importance of using this new machine will be addressed in this paper. Because of the ease of use for this new device, testing can be accomplished in hours. To check repeatability, repeat testing can be done in a short period of time. This rapid testing is the main advantage of the new generation of SPMD's. The new SPMD collects raw data from transducers. All data are stored in the computer. Some are used directly to generate graphic outputs. Some are utilized to calculate wanted parameters. Graphs are generated so that some characteristics can be scrutinized. Parameters can be presented either by points or by cross plotting in graphs.

A study is being conducted in which both component level and full scale crash tests are being compared. This report documents the approach selected for component level testing and the matrix selected for full scale crash testing. The hardware that was fabricated to conduct the component tests is shown and discussed. The component test results to date are discussed as to repeatability, durability and ability to discriminate between levels of safety.

It is commonly recommended to use infant/child restraints in the rear seat, and that until an infant reaches certain age, weight and height criteria, the infant restraint should be placed rear facing. This paper will describe the injuries suffered by an infant that was restrained in a forward-facing child seat placed in the front passenger seating position during a real world collision. Based on this collision, a full-scale vehicle to barrier impact test was performed. For this test, two 6-month-old CRABI dummies were used in identical child restraints. One of the restraints was placed in the front passenger seat in a forward facing configuration, and the other was placed in the right rear seating position in a rear-facing configuration. This paper provides a detailed discussion of the results of this test, including comparisons of the specific kinematics for both the restraint/child dummy configurations.

Many vehicle-to-pole impacts occur when a vehicle leaves the roadway due to oversteer and loss of control in a lateral steering maneuver. Such a loss of control typically results in the vehicle having a significant component of lateral sliding motion as it crosses the road edge, so that impacts with objects off of the roadway often occur to the side of the vehicle. The response of the vehicle to this impact depends on the characteristics of the impacted object, the characteristics of the vehicle in the impacted zone, and the speed and orientation of the vehicle. In situations where the suspension or other stiff portions of a vehicle contacts a wooden pole, it is not uncommon for the pole to fracture. When this occurs, reconstruction of the accident is complicated by the need to evaluate both the energy absorbed by the vehicle as well as the energy absorbed by the pole.

Accident reconstructionists use several different approaches to determine vehicle equivalent impact speed from damage due to narrow object impacts. One method that is used relates maximum crush to equivalent impact speed with a bilinear curve. In the past, this model has been applied to several passenger cars with unibody construction. In this paper, the approach is applied to a body-on-frame vehicle. Several vehicle-to-rigid pole impact tests have been conducted on a full-size pickup at different speeds and impact locations: centrally located across the vehicle's front and outside the frame rail. A bilinear model relating vehicle equivalent impact speed to maximum crush is developed for the impact locations. These results are then compared to results obtained from other body-on-frame vehicles as well as unibody vehicles. Other tests such as impacts on the frame rail and barrier impacts are also presented. Limitations to this bilinear approach are discussed.

The International Harmonization Research Activities Pedestrian Safety Working Group (IHRA PSWG) has proposed design requirements for two head-forms for vehicle hood (bonnet) impact testing. This paper discusses the development of MADYMO models representing the IHRA adult and child head-forms, validation of the models against laboratory drop tests, and assessment of the effect of IHRA geometric and mass constraints on the model response by conducting a parameter sensitivity analysis. The models consist of a multibody rigid sphere covered with a finite element modeled vinyl skin. The most important part in developing the MADYMO head-form models was to experimentally determine the material properties of the energy-absorbing portion of the head-form (vinyl skin) and incorporate these properties into MADYMO using a suitable material model. Three material models (linear isotropic, viscoelastic, hyperelastic) were examined.

Multi-body simulations are very powerful tools in the modeling of dynamic mechanical systems. This study uses the multi-body simulation program ADAMS to analyze a light vehicle suspension. The paper introduces ADAMS modeling concepts and then applies them in a case study examining the effects of additional longitudinal compliance on the ride and handling behavior of a 1/4 car suspension model. The results were a marginal increase in the lateral stiffness of the vehicle, approximately the same ride performance, and an increase in the compliance steering angle.

Experimental reconstructions of pedestrian accidents involving head injury sustained primarily from hood impact were conducted to determine the relationship between HIC and injury severity. The purpose was to establish the capability of predicting pedestrian head injury severity in simple laboratory tests. The reconstruction test results were analyzed by a median ranking technique to provide a family of curves showing probability of injury of AIS 3, 4, and 5 severities as a function of HIC. This analysis method was used by Prasad and Mertz [1]1 to develop a head injury risk curve from cadaver head impact test data. Results of the two analyses were compared to determine the degree of agreement between the HIC/injury-risk relationship derived from controlled experiments with cadavers and that derived from uncontrolled accidents involving live people. The reconstruction test results also were used to derive a relationship between head injury risk (HIC) and vehicle impact speed.

This paper presents the methodology of the investigative techniques for examining vehicular fires. Discussion illustrating the mechanical “finger prints” that show the investigating team the mechanism of fire spread is presented. The common causes of vehicular fires and examples of each are discussed. The techniques used by the forensic chemist in determining incendiary fires and the use of specialized equipment in the investigation are illustrated. Tests are discussed to show the theories postulated in the investigative stages of the vehicle examination. Lastly, the interdisciplinary team approach to the investigation is discussed showing the validity of “forensic” engineering and chemistry in examining vehicle fires.

A technique has been developed to study the effects of the vehicle interior on the performance of child safety seats. Child safety seat sled tests are used to define the kinematics of the seat and child in a crash situation. Computer animation of this motion is superimposed on the motion of the actual vehicle crash tests giving an estimation of the kinematics of the child and child seat in a real crash situation. The significance of the vehicle interior and the interference of the vehicle interior with the child's kinematics is presented within the computer animation. The analysis is conducted using a single child restraint device in multiple seating conditions within a single vehicle.

The measurement of angular rotation has many applications in crash testing, particularly in tracking the motion of crash dummies. There are currently a few devices for determining angular rotation. These include accelerometer arrays, magnetohydrodynamic (MHD) sensors, potentiometers, and high speed films. However, there are problems associated with all of these methods. Systron Donner has developed a new device called a “Quartz Rate Sensor” or “QRS”. The QRS utilizes a piezoelectric chip which produces a DC voltage proportional to the rate of rotation of the sensor about its sensitive axis. Angular displacement can then be determined from a simple integration. Results of preliminary tests performed at The U.S. Department of Transportation's Vehicle Research and Test Center suggest that the QRS's yield very accurate results.

This paper presents the results of an in-depth study of the measurement of occupant kinematic response on the S-E-A Roll Simulator. This roll simulator was built to provide an accurate and repeatable test procedure for the evaluation of occupant protection and restraint systems during roll events within a variety of occupant compartments. In the present work this roll simulator was utilized for minimum-energy, or threshold type, rollover events of recreational off-highway vehicles (ROVs). Input profiles for these tests were obtained through a separate study involving autonomous full vehicle tests [1]. During simulated roll events anthropomorphic test device (ATD) responses were measured using on-board high speed video, an optical three-dimensional motion capture system (OCMS) and an array of string potentiometers.