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Lab-to-lab differences have become a very important consideration in the verification testing of Hybrid III 5th Female necks in user labs. It has been observed that a neck certified by one laboratory does not always pass the same certification test in a different lab. This has led the Anthropomorphic test device Certification Research group (ACR) to investigate the precision of the test procedure in relation to the test specification corridors. This study adapts an industry recognized ASTM procedure to measure the precision of the SAE neck calibration laboratory test procedure in Engineering Aid 25 [1]. The ASTM procedure is ASTM E 691-99 “Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method” [2]. This paper details how the ASTM procedure was adapted and presents the results of the ASTM E 691 statistical analysis procedures.

This study by the Anthropomorphic test device Certification Research group (ACR) takes a new look at dummy neck rotation measurement methods. The authors' previous SAE Congress paper, Watters et al., 2005, focused on comparing three different rotary pot measurement systems in the same Hybrid III 5th Female neck flexion test at a single laboratory [1]. Differences between the pot systems, and between the pot systems and video analysis of the head rotation, were found to be a significant component of the observed test variation. The 2005 rotary potentiometer study used a modified head known as the Nine Accelerometer Array Head (NAAH). The NAAH data for rotation about the Y-axis, only recently analyzed, showed exceptional agreement with the video analysis as compared to the rotary potentiometer data.

Lab-to-lab differences are an important consideration in the verification testing of Hybrid III dummy necks in user labs. The authors, the Anthropomorphic test device Certification Research group (ACR), conducted and presented two previous studies investigating lab to lab differences in Hybrid III 5th female dummy neck certification results [1, 2]. The results of both studies underscored the need to have better controls on the test procedure. The complex procedure for dummy neck certification has many setup factors that can contribute to test variation and unacceptable precision. Two steps within this protocol - two aspects of the neck's physical setup - were identified by the ACR group as potential sources for variation: 1) setting the pre-test D-plane angle by neck bracket adjustment, and 2) setting the torque on the neck cable. Fifth female neck flexion tests were conducted with variations in these factors to determine their effect on neck test results.

Lab to lab differences in the testing of the Hybrid III 5th female dummy neck have led to the same neck passing in one lab and failing in another. Several indicators led to the hypothesis that the neck rotation measurement system is a critical factor in the differences observed. The Transportation Research Center Inc. and Denton ATD Inc. collaboratively conducted tests to understand the nature and importance of any differences obtained when different measurement devices are used. Dummy testing laboratories today use a neck rotation measurement system consisting of two rotary potentiometers, one attached to the neck/pendulum interface and one attached to the pivot pin which moves with the head of the dummy, plus a linkage between the two potentiometers (pots). The data from the two pots is summed for a total rotation. Neck testing was performed on two necks (of different manufacture) to investigate the effect of three rotation measurement assemblies' designs and masses.

To improve the biofidelity of the currently available Hybrid III 10-year-old (HIII-10C) Anthropomorphic Test Device (ATD), the National Highway Traffic Safety Administration (NHTSA) has developed the Large Omnidirectional Child (LODC) ATD. The LODC head is a redesigned HIII-10C head with mass properties and modified skin material required to match pediatric biomechanical impact response targets from the literature. A dynamic, nonlinear finite element (FE) model of the LODC head has been developed using the mesh generating tool Hypermesh based on the three-dimensional CAD model. The material data, contact definitions, and initial conditions are defined in LS-PrePost and converted to LS-Dyna solver input format. The aluminum head skull is stiff relative to head flesh material and was thus modeled as a rigid material. For the actual LODC, the head flesh is form fit onto the skull and held in place through contact friction.

Testing vision-based advanced driver assistance systems (ADAS) in a Camera-in-the-Loop (CiL) bench setup, where external visual inputs are used to stimulate the system, provides an opportunity to experiment with a wide variety of test scenarios, different types of vehicle actors, vulnerable road users, and weather conditions that may be difficult to replicate in the real world. In addition, once the CiL bench is setup and operating, experiments can be performed in less time when compared to track testing alternatives. In order to better quantify normal operating zones, track testing results were used to identify behavior corridors via a statistical methodology. After determining normal operational variability via track testing of baseline stationary surrogate vehicle and pedestrian scenarios, these operating zones were applied to screen-based testing in a CiL test setup to determine particularly challenging scenarios which might benefit from replication in a track testing environment.

In ISO Technical Report 9790 (1999) normalized lateral and oblique thoracic force-time responses of PMHS subjected to blunt pendulum impacts at 4.3 m/s were deemed sufficiently similar to be grouped together in a single biomechanical response corridor. Shaw et al., (2006) presented results of paired oblique and lateral thoracic pneumatic ram impact tests to opposite sides of seven PMHS at sub-injurious speed (2.5 m/s). Normalized responses showed that oblique impacts resulted in more deflection and less force, whereas lateral impacts resulted in less deflection and more force. This study presents results of oblique and lateral thoracic impacts to PMHS at higher speeds (4.5 and 5.5 m/s) to assess whether lateral relative to oblique responses are different as observed by Shaw et al., or similar as observed by ISO.

The goal of this study is to evaluate both the internal and external biofidelity of existing rear impact anthropomorphic test devices (BioRID II, RID3D, Hybrid III 50th) in two moderate-speed rear impact sled test conditions (8.5g, 17 km/h; 10.5g, 24 km/h) by quantitatively comparing the ATD responses to biomechanical response targets developed from PMHS testing in a corresponding study. The ATDs and PMHS were tested in an experimental seat system that is capable of simulating the dynamic seat back rotation response of production seats. The experimental seat contains a total of fourteen load cells installed such that external loads from the ATDs and PMHS can be measured to evaluate external biofidelity. The PMHS were instrumented to correspond to the instrumentation contained in the ATDs so that direct comparison between ATDs and PMHS could be made to evaluate internal biofidelity.

The objectives of this study were to obtain biomechanical responses of post mortem human subjects (PMHS) by subjecting them to two moderate-speed rear impact sled test conditions (8.5g, 17 km/h; 10.5g, 24 km/h) while positioned in an experimental seat system, and to create biomechanical targets for internal and external biofidelity evaluation of rear impact ATDs. The experimental seat was designed to measure external loads on the head restraint (4 load cells), seat back (6 load cells), and seat pan (4 load cells) such that subject dynamic interaction with the seat could be evaluated. This seat system was capable of simulating the dynamic characteristics of modern vehicle seat backs by considering the moment-rotation properties of a typical passenger vehicle, thus providing a more realistic test environment than using a rigid seat with a non-rotating seat back as done in previous studies.

When the Hybrid III 10-year old (HIII-10C) anthropomorphic test device (ATD) was adopted into Code of Federal Regulations (CFR) 49 Part 572 as the best available tool for evaluating large belt-positioning booster seats in Federal Motor Vehicle Safety Standard (FMVSS) No. 213, NHTSA stated that research activities would continue to improve the performance of the HIII-10C to address biofidelity concerns. A significant part of this effort has been NHTSA’s in-house development of the Large Omnidirectional Child (LODC) ATD. This prototype ATD is comprised of (1) a head with pediatric mass properties, (2) a neck that produces head lag with Z-axis rotation at the atlanto-occipital joint, (3) a flexible thoracic spine, (4) multi-point thoracic deflection measurement capability, (5) skeletal anthropometry representative of a seated child, and (6) an abdomen that can directly measure belt loading.

Side impacts are disproportionately injurious for children compared to other crash directions. Far side impacts allow for substantial translation and rotation of child restraint systems (CRS) because the CRS does not typically interact with any adjacent structures. The goal of this study is to determine whether minor installation incompatibilities between CRS and vehicle seats cause safety issues in far side crashes. Four non-ideal CRS installation conditions were compared against control conditions having good fit. Two repetitions of each condition were run. The conditions tested were: 1) rear-facing (RF) CRS installed with a pool noodle to create proper recline angle, 2) RF CRS with narrow base, 3) forward-facing (FF) CRS with gap behind back near seat bight (i.e., vehicle seat angle too acute for CRS), 4) FF CRS with gap behind back near top of CRS (i.e., vehicle seat angle too obtuse for CRS). Second row captain’s chairs were set up at 10° anterior of lateral.

The Large Omnidirectional Child (LODC) developed by the National Highway Traffic Safety Administration (NHTSA) has an improved biofidelity over the currently available Hybrid III 10-year-old (HIII-10C) Anthropomorphic Test Device (ATD). The LODC design incorporates enhancements to many body region subassemblies, including a redesigned HIII-10C head with pediatric mass properties, and the neck, which produces head lag with Z-axis rotation at the atlanto-occipital joint, replicating the observations made from human specimens. The LODC also features a flexible thoracic spine, a multi-point thoracic deflection measurement system, skeletal anthropometry that simulates a child's sitting posture, and an abdomen that can measure belt loading directly. This study presents the development and validation of a dynamic nonlinear finite element model of the complete LODC dummy. Based on the three-dimensional CAD model, Hypermesh was used to generate a mesh of the finite element (FE) LODC model.