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There has been recent progress over the past 10 years in research comparing 6-year-old thoracic and abdominal response of pediatric volunteers, pediatric post mortem human subjects (PMHS), animal surrogates, and 6-year-old ATDs. Although progress has been made to guide scaling laws of adult to pediatric thorax and abdomen data for use in ATD design and development of finite element models, further effort is needed, particularly with respect to lateral impacts. The objective of the current study was to use the impact response data of age equivalent swine from Yaek et al. (2018) to assess the validity of scaling laws used to develop lateral impact response corridors from adult porcine surrogate equivalents (PSE) to the 3-year-old, 6-year-old, and 10-year-old for the thorax and abdominal body regions.

Analysis and validation of current scaling relationships and existing response corridors using animal surrogate test data is valuable, and may lead to the development of new or improved scaling relationships. For this reason, lateral pendulum impact testing of appropriate size cadaveric porcine surrogates of human 3-year-old, 6-year-old, 10-year-old, and 50th percentile male age equivalence, were performed at the thorax and abdomen body regions to compare swine test data to already established human lateral impact response corridors scaled from the 50th percentile human adult male to the pediatric level to establish viability of current scaling laws. Appropriate Porcine Surrogate Equivalents PSE for the human 3-year-old, 6-year-old, 10-year-old, and 50th percentile male, based on whole body mass, were established. A series of lateral impact thorax and abdomen pendulum testing was performed based on previously established scaled lateral impact assessment test protocols.

An understanding of stiffness characteristics of different body regions, such as thorax, abdomen and pelvis of ES-2re and SID-IIs dummies under controlled laboratory test conditions is essential for development of both compatible performance targets for countermeasures and occupant protection strategies to meet the recently updated FMVSS214, LINCAP and IIHS Dynamic Side Impact Test requirements. The primary purpose of this study is to determine the transfer functions between the ES-2re and SID-IIs dummies for different body regions under identical test conditions using flat rigid wall sled tests. The experimental set-up consists of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and femur/knee impacting a stationary dummy seated on a rigid low friction seat at a pre-determined velocity.

The main purpose of this study was to determine the impact responses of the different body regions (shoulder, thorax, abdomen and pelvis/leg) of the ES-2re and SID-IIs dummies using rigid wall impacts under different initial test conditions. The experimental set-up consisted of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and knee impacting a stationary dummy seated on a rigid seat at a pre-determined velocity. The relative location and orientation of the load-wall plates was adjusted relative to the body regions of the ES-2re and SID-IIs dummies respectively.

The main purpose of this study was to determine the impact responses of the different body regions (shoulder, thorax, abdomen and pelvis/leg) of the ES-2re and SID-IIs dummies using rigid wall impacts under different initial test conditions. The experimental set-up consisted of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and knee impacting a stationary dummy seated on a rigid seat at a pre-determined velocity. The relative location and orientation of the load-wall plates was adjusted relative to the body regions of the ES-2re and SID-IIs dummies respectively.

In the automotive seating industry measurements of lumbar support prominence and height are performed to assess their effects on occupant comfort. This project investigated measurement methods for lumbar support prominence and height in an occupied seat. Fifteen participants provided subjective responses of their perceived lumbar support prominence and height utilizing specifically developed visual analog scales. Also, pressure measurements were taken while the participants were seated. The recently developed H-point manikin II was utilized as a standardized sitter. Specifically, the lumbar support prominence (LSP) measure was used for the prominence measures. Pressure mat readings with the seated manikin was used for lumbar support height determination and prominence correlations. With both manikin and participants in the seat, the lumbar support was digitized through the rear of the seat.

To date, several lateral impact studies (Bolte et al., 2000, 2003, Marth, 2002 and Compigne et al., 2004) have been performed on the shoulder to determine the response characteristics and injury threshold of the shoulder complex. Our understanding of the biomechanical response and injury tolerance of the shoulder would be improved if the results of these tests were combined. From a larger data base shoulder injury tolerance criteria can be developed as well as corridors for side impact dummies. Data from the study by Marth (2002, 12 tests) was combined with data from the previous studies. Twenty-two low speed tests (4.5 ± 0.7 m/s) and 9 high speed tests (6.7 ± 0.7 m/s) were selected from the combined data for developing corridors. Shoulder force, deflection and T1y acceleration corridors were developed using a minimization of cumulative variance technique.

Thirty-three fresh human cadaver shoulders were harvested and bone-ligament-bone specimens of acromioclavicular joint, coracoclavicular joint and sternoclavicular joint were obtained. A test fixture and clamps specifically designed for this ligament study and a high-speed Instron machine were used. One quasi-static rate (nominally 0.1 %/sec) and two high rates (nominally, high rate 1 = 40,000 %/sec and high rate 2 = 15,000 %/sec) were used in this study. In the acromioclavicular joint tests, ligament failure was the most common failure mode. Bone fractures occurred most often at the clavicle rather than acromion. In the coracoclavicular joint tests, the majority of specimens failed at the ligament and bone fractures occurred at the coracoid. In the sternoclavicular joint tests, the specimen failed at the bone in most cases. In the acromioclavicular joint and coracoclavicular joint tests, high rate 2 tests and quasi-static tests had more bone fracture cases than high rate 1 tests.

The biomechanical response and injury tolerance of the shoulder in lateral impacts is not well understood. These data are needed to better understand human injury tolerance, validate finite element models and develop biofidelic shoulders in side impact dummies. Seventeen side impact sled tests were performed with unembalmed human cadavers. Data analyzed for this study include T1-Y acceleration, shoulder and thoracic load plate forces, upper sternum x and y accelerations, and struck side acromion x, y and z accelerations. One dimensional deflection at the shoulder level was determined from high-speed film by measuring the distance between a target on T1 and the impacted wall. Force-time response corridors were obtained for tests with 9 m/s pelvic offset, 10.5 m/s pelvic offset, 9 m/s unpadded flat wall, 6.7 m/s unpadded flat wall, 9 m/s soft padding and 9 m/s stiff padding. Maximum shoulder plate forces in unpadded 9 m/s tests (5.5 kN) were larger than in 6.7 m/s tests (3.3 kN).

A sled-to-sled subsystem side impact test methodology has been developed by using two sleds at the WSU Bioengineering Center in order to simulate a car-to-car side impact, particularly in regards to the door velocity profile. Initially this study concentrated on tailoring door pulse to match the inner door velocity profile from FMVSS 214 full-scale dynamic side impact tests. This test device simulates a pulse quite similar to a typical door velocity of a full size car in a dynamic side impact test. Using the newly developed side impact test device three runs with a SID dummy were performed to study the effects of door padding and spacing in a real side impact situation. This paper describes the test methodology to simulate door intrusion velocity profiles in side impact and discusses SID dummy test results for different padding conditions.

The purpose of this paper is to address abdominal injury and response in cadaver whole body side impacts and abdominal injury risk functions in SID and BIOSID in whole body impacts. Side impact sled tests were performed at Wayne State University using cadavers, SID and BIOSID, with response measured at the shoulder, thorax, abdominal and pelvic levels. The data at the abdominal level are presented here. These data provide further understanding of abdominal tolerance and response in lateral impact and the ability of side impact dummies to predict abdominal injury. In addition, the padding data provide insight into tolerable armrest loads.

Seventeen Heidelberg type cadaveric side impact sled tests, two sled-to-sled tests, and forty-four pendulum tests have been conducted at Wayne State University, to determine human responses and tolerances in lateral collisions. This paper describes the development of a simplified finite element model of a human occupant in a side impact configuration to simulate those cadaveric experiments. The twelve ribs were modeled by shell elements. The visceral contents were modeled as an elastic solid accompanied by an array of discrete dampers. Bone condition factors were obtained after autopsy to provide material properties for the model. The major parameters used for comparison are contact forces at the level of shoulder, thorax, abdomen and pelvis, lateral accelerations of ribs 4 and 8 and of T12, thoracic compression and injury functions V*C, TTI and ASA.

Three-dimensional film analysis was used to study the response of the shoulder and thoracic skeleton of cadavers to lateral sled tests conducted at Wayne State University. The response of the shoulder structure was of particular interest, although, it is perhaps the most difficult skeletal structure to track in a side impact. Results of the three-dimensional film analysis are given for rigid impacts at 6.7 and 9.1 meters per second, and for padded impacts averaging 9 meters per second. Results from a two-dimensional film analysis are included for the impacted clavicle which could not be tracked by the three-dimensional film analysis. Displacements at various locations on the shoulder and thoracic skeleton were normalized to estimate the response of a fiftieth percentile male.

Lateral impact testing has been performed on the shoulder, thorax, abdomen and pelvis of human cadavers by several investigators. The impacts have either been whole body impacts in sled tests or pendulum type impacts to the separate regions. Based on the forces produced in these tests and the accompanying injury, initial recommendations can be made on force-tolerance and padding tolerance to the various regions of the human body in side impact. The pelvis has the highest force tolerance, followed by the shoulder, abdomen and thorax. Padding crush strength tolerance based on these forces and estimated contact areas are presented. This information is of practical importance to engineers who design door interior trim for side impact safety.

Various types of padding have been used in side impact sled tests with cadavers. This paper presents a summary of performance of the padding used in NHTSA and WSU/CDC sled tests, and a summary of material properties of padding used in cadaveric sled tests. The purpose of this paper is to provide information on padding performance in cadavers, rather than optimum padding performance in dummies.

Heidelberg-type side impact sled tests were conducted using SID side impact dummies. These tests were run under similar conditions to a series of cadaveric sled tests funded by the Centers for Disease Control in the same lab. Tests included 6.7 and 9 m/s (15 and 20 mph) unpadded and 9 m/s padded tests. The following padding was used at the thorax: ARSAN, ARCEL, ARPAK, ARPRO, DYTHERM, 103 and 159 kPa (15 and 23 psi) crush strength paper honeycomb, and an expanded polystyrene. In all padded tests the dummy Thoracic Trauma Index, TTI(d) was below the value of 85 set by federal rulemaking (49 CFR, Part 571 et al., 1990). In contrast, cadavers in 9 m/s sled tests did not tolerate ARSAN 601 (MAIS 5) and 23 psi (159 kPa) paper honeycomb (MAIS 5), and 20 psi (138 kPa) Verticel™ honeycomb (MAIS 4), but tolerated 15 psi (103 kPa) paper honeycomb (average thoracic MAIS 2.3 in six tests).

Facial impact experiments were conducted on eleven unembalmed human cadavers. A 32 kg or 64 kg impactor with a 25 mm diameter, rigid, cylindrical contact surface was oriented in the left-right direction relative to the face and contacted the nose at the elevation of the infraorbital margins. The impactor was propelled toward the race along an anterior-to-posterior path, with contact velocities ranging from 10 to 26 km/h. Accelerometers mounted on the impactor and the occiput provided data for analyzing the dynamics of the impacts. While the threshold for nasal bone fractures was not determined, it appears that a peak force of about 3 kN (filtered 180 Hz) is a representative threshold for more severe fracture patterns. A preliminary dynamic force vs penetration response specification for the above mode of loading is offered.