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Described in this paper is a component test methodology to evaluate the door trim armrest performance in an Insurance Institute for Highway Safety (IIHS) side impact test and to predict the SID-IIs abdomen injury metrics (rib deflection, deflection rate and V*C). The test methodology consisted of a sub-assembly of two SID-IIs abdomen ribs with spine box, mounted on a linear bearing and allowed to translate in the direction of impact. The spine box with the assembly of two abdominal ribs was rigidly attached to the sliding test fixture, and is stationary at the start of the test. The door trim armrest was mounted on the impactor, which was prescribed the door velocity profile obtained from full-vehicle test. The location and orientation of the armrest relative to the dummy abdomen ribs was maintained the same as in the full-vehicle test.

A series of rigid wall tests have been conducted at three impact velocities to quantify the dynamic response of the Side Impact Dummy (SID) developed by US DOT. This paper reports the chest, pelvis and head responses of the dummy at various filter frequencies and describes the development and verification of the three-dimensional mathematical model of the Side Impact Dummy utilizing the rigid wall test results. The mathematical model uses the mass distribution and the linkage system of the current Part 572, Hybrid II dummy which forms the basic platform of the SID. The unique chest of the dummy is modeled by two systems of linkages simulating the rib cage and the jacket. Also included in the model is the internal hardware of the chest, e.g. a damper, rib stopper and a clavicle simulator at the upper spine. The material and linkage models are based on static and dynamic tests of the dummy components.

This paper describes the development of a three-dimensional lumped-mass structure and dummy model to study barrier-to-car side impacts. The test procedures utilized to develop model input data are also described. The model results are compared to crash test results from a series of six barrier-to-car crash tests. Sensitivity analysis using the validated model show the necessity to account for dynamic structural rate effects when using quasi-statically measured vehicle crush data.

Two 50th percentile anthropomorphic test devices are specified as alternate test devices for FMVSS 208 compliance testing. These test devices are commonly known as the Hybrid II and the Hybrid III dummies. The designs of the two dummies are different, representing the state-of-the-art in the time frame of their designs. The trajectory differences between the two dummies have been published in the literature, but response differences, e.g., HIC and chest acceleration are not available in the literature. To quantify response differences between the two dummies, a series of sled tests with open bucks and with bucks simulating vehicle interior were conducted with restrained dummies. Additional crash tests were also conducted with the two dummies. This paper reports on an analysis of the data from the above series of tests. The data indicate that in non-head contact simulations with belt restraint systems, Hybrid III HIC's are nearly 50% higher than Hybrid II HIC's.

The objective of this study was to analyze available anthropomorphic test device (ATD) responses from KARCO rear impact tests and to evaluate an injury predictive model based on crash severity and occupant weight presented by Saczalski et al. (2004). The KARCO tests were carried out with various seat designs. Biomechanical responses were evaluated in speed ranges of 7-12, 13-17, 18-23 and 24-34 mph. For this analysis, all tests with matching yielding and stiff seats and matching occupant size and weight were analyzed for cases without 2nd row occupant interaction. Overall, the test data shows that conventional yielding seats provide a high degree of safety for small to large adult occupants in rear crashes; this data is also consistent with good field performance as found in NASS-CDS. Saczalski et al.'s (2004) predictive model of occupant injury is not correct as there are numerous cases from NASS-CDS that show no or minor injury in the region where serious injury is predicted.

Macroscopic constitutive behaviors of aluminum 5052-H38 honeycombs under dynamic inclined loads with respect to the out-of-plane direction are investigated by experiments. The results of the dynamic crush tests indicate that as the impact velocity increases, the normal crush strength increases and the shear strength remains nearly the same for a fixed ratio of the normal to shear displacement rate. The experimental results suggest that the macroscopic yield surface of the honeycomb specimens as a function of the impact velocity under the given dynamic inclined loads is not governed by the isotropic hardening rule of the classical plasticity theory. As the impact velocity increases, the shape of the macroscopic yield surface changes, or more specifically, the curvature of the yield surface increases near the pure compression state.

This study applies a detailed finite element model of the human body to simulate occupant knee impacts experienced in vehicular frontal crashes. The human body model includes detailed anatomical features of the head, neck, chest, thoracic and lumbar spine, abdomen, and lower and upper extremities. The material properties used in the model for each anatomic part of the human body were obtained from test data reported in the literature. The total human body model used in the current study has been previously validated in frontal and side impacts. Several cadaver knee impact tests representing occupants in a frontal impact condition were simulated using the previously validated human body model. Model impact responses in terms of force-time and acceleration-time histories were compared with test results. In addition, stress distributions of the patella, femur, and pelvis were reported for the simulated test conditions.

Development of frontal impact airbag sensor algorithms/calibrations requires crash signals, which can be obtained from vehicle crash testing and/or CAE simulations. This paper presents the development of finite element sensor models to generate CAE simulated crash pulses/signals at the sensing location during frontal impacts. These signals will be evaluated for potential used in the airbag sensor algorithm/calibration.

A theoretical, mathematical, risk assessment procedure was developed to estimate the fraction of drivers that incurred head and thoracic AIS3+ injuries in full-engagement frontal crashes. The estimates were based on numerical simulations of various real-world events, including variations of crash severity, crash speed, level of restraint, and occupant size. The procedure consisted of four steps: (1) conduct the simulations of the numerous events, (2) use biomechanical equations to transform the occupant responses into AIS3+ risks for each event, (3) weight the maximum risk for each event by its real-world event frequency, and (4) sum the weighted risks. To validate the risk assessment procedure, numerous steps were taken. First, a passenger car was identified to represent average field performance.

Risk curves are developed for several crash data sets, expressing the probabilities of injury as a function of HIC, Extension Moment, Neck Tension and Maximum Deflection, respectively. The statistical method uses concept of thresholds that are interval censored and right censored. A combined evaluation method is used to select a “best” curve among the curves derived from various methods.

The result of two series of crash tests, 5 tests each series, are presented in this paper. Two car designs were subjected to various frontal impacts - full frontal, car-to-car 60% offset, 50% offset, and 50% offset with deformable barrier - at 56 km/h. Two tests were conducted at 60 km/h against the ECE deformable barrier with 40% overlap. Structural and occupant responses are compared between the various test conditions.

The potential of head injury in frontal barrier impact tests was investigated by a mathematical model which consisted of a finite element human head model, a four segments rigid dynamic neck model, a rigid body occupant model, and a lumped-mass vehicle structure model. The finite element human head model represents anatomically an average adult head. The rigid body occupant model simulates an average adult male. The structure model simulates the interior space and the dynamic characteristics of a vehicle. The neck model integrates the finite element human head to the occupant body to give a more realistic kinematic head motion in a barrier crash test. Model responses were compared with experimental cadaveric data and vehicle crash data for the purpose of model validation to ensure model accuracy. Model results show a good agreement with those of the tests.

Locations of key body segments of Hybrid III dummies used in FMVSS 208 compliance tests and NCAP tests were measured and subjected to statistical analysis. Mean clearance dimensions and their standard deviations for selected body segments of driver and passenger occupants with respect to selected vehicle surfaces were determined for several classes of vehicles. These occupant locations were then investigated for correlation with impact responses measured in crash tests and by using a three dimensional human-dummy mathematical model in comparable settings. Based on these data, the importance of some of the clearance dimensions between the dummy and the vehicle surfaces was determined. The study also compares observed Hybrid III dummy positions within selected vehicles with real world occupant positions reported in published literature.

Axial loading of the calcaneus-talus-tibia complex is an important injury mechanism for moderate and severe vehicular foot-ankle trauma. To develop a more definitive and quantitative relationship between biomechanical parameters such as specimen age, axial force, and injury, dynamic axial impact tests to isolated lower legs were conducted at the Medical College of Wisconsin (MCW). Twenty-six intact adult lower legs excised from unembalmed human cadavers were tested under dynamic loading using a mini-sled pendulum device. The specimens were prepared, pretest radiographs were taken, and input impact and output forces together with the pathology were obtained using load cell data. Input impact forces always exceeded the forces recorded at the distal end of the preparation. The fracture forces ranged from 4.3 to 11.4 kN.

Global engineering is increasingly becoming a practice within the automotive industry. Due to added engineering and manufacturing benefits, more and more new vehicles are being developed with common structure to meet the consumer needs in many local regions. While vehicle development and manufacturing process is becoming global, automotive safety regulations in various parts of the world have not been as uniform. A good example is the differing requirements for dynamic side impact protection of new vehicles. United States National Highway Traffic Safety Administration (NHTSA) and European Union (EU) have each produced their own distinct test procedures such as, different barrier faces, impact configurations, and anthropomorphic test devices (dummies). Although both test procedures have the same final objective estimate occupant responses in side impacts, they differ greatly in execution and emphasis on occupant response requirements.

This paper presents an image analysis of a laboratory-based rollover crash test using camera-matching photogrammetry. The procedures pertaining to setup, analysis and data process used in this method are outlined. Vehicle roll angle and rate calculated using the method are presented and compared to the measured values obtained using a vehicle mounted angular rate sensor. Areas for improvement, accuracy determination, and vehicle kinematics analysis are discussed. This paper concludes that the photogrammetric method presented is a useful tool to extract vehicle roll angle data from test video. However, development of a robust post-processing tool for general application to crash safety analysis requires further exploration.

Full vehicle dynamic crash tests are commonly used in the development of rollover detection sensors, algorithms and occupant protection systems. However, many published studies have utilized component level rollover test fixtures for rollover related occupant kinematics studies and restraint system evaluation and development. A majority of these fixtures attempted to replicate only the rotational motion that occurs during the free flight phase of a typical full vehicle rollover crash test. In this paper, a description of the methods used to design a new dynamic component rollover test device is presented. A brief summary of several existing rollover component test methods is included. The new system described in this paper is capable of replicating the transfer of lateral energy into rotational vehicle motion that is present in many tripped laboratory based rollover crash tests.

The ability to extract and evaluate the time history of structural deformations or crush during vehicle crashes represents a significant challenge to automotive safety researchers. Current methods are limited by the use of electro-mechanical devices such as string pots and/or linear variable displacement transducers (LVDT). Typically, one end of the transducer must be mounted to a point on the structure that will remain un-deformed during the event; the other end is then attached to the point on the structure where the deformation is to be measured. This approach measures the change in distance between these two points and is unable to resolve any movement into its respective X, Y, or Z directions. Also, the accuracy of electro-mechanical transducers is limited by their dynamic response to crash conditions. The photogrammetry technique has been used successfully in a wide variety of applications including aerial surveying, civil engineering and documentation of traffic accidents.

This paper compares and contrasts the modeling features present in the MVMA2D and the MADYM02D occupant simulation models. Simulations of a series of sled tests with a Hybrid II test dummy restrained with a 3-point belt system have been conducted using the MADYM02D model. The simulation results agree with the test results.

The objective of this study was to analyze available anthropomorphic test device (ATD) responses from FMVSS 301-type rear impact tests. Rear impact test data was obtained from NHTSA and consisted of dummy responses, test observations, photos and videos. The data was organized in four test series: 1) NCAP series of 30 New Car Assessment Program tests carried out at 35 mph with 1979-1980 model year vehicles, 2) Mobility series of 14 FMVSS 301 tests carried out at 30 mph with 1993 model year vehicles, 3) 301 MY 95+ series of 79 FMVSS 301 tests carried out at 30 mph with 1995-2005 model year vehicles and 4) ODB series of 17 Offset Deformable Barrier tests carried out at 50 mph with a 70% overlap using 1996-1999 model year vehicles. The results indicate very good occupant performance in yielding seats in the NCAP, Mobility and 301 MY 95+ test series.