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With the evolution of telemetry technology in vehicles, Advanced Automatic Collision Notification (AACN), which detects occupants at risk of serious injury in the event of a crash and triages them to the trauma center quickly, may greatly improve their treatment. An Injury Severity Prediction (ISP) algorithm for AACN was developed using a logistic regression model to predict the probability of sustaining an Injury Severity Score (ISS) 15+ injury. National Automotive Sampling System Crashworthiness Data System (NASS-CDS: 1999-2015) and model year 2000 or later were filtered for new case selection criteria, based on vehicle body type, to match Subaru vehicle category. This new proposed algorithm uses crash direction, change in velocity, multiple impacts, seat belt use, vehicle type, presence of any older occupant, and presence of any female occupant.

High pressure EGR provides NOx emission reduction even at low exhaust temperatures. To maintain a safe EGR system operation over a required lifetime, the EGR cooler fouling must not exceed an allowable level, even if the engine is operated under worst-case conditions. A reliable fouling simulation model represents a valuable tool in the engine development process, which validates operating and calibration strategies regarding fouling tendency, helping to avoid fouling issues in a late development phase close to series production. Long-chained hydrocarbons in the exhaust gas essentially impact the fouling layer formation. Therefore, a simulation model requires reliable input data especially regarding mass flow of long-chained hydrocarbons transported into the cooler. There is a huge number of different hydrocarbon species in the exhaust gas, but their individual concentration typically is very low, close to the detection limit of standard in-situ measurement equipment like GC-MS.

Knee airbags (KABs) are one countermeasure in newer vehicles that could influence lower extremity (LEX) injury, the most frequently injured body region in frontal crashes. To determine the effect of KABs on LEX injury for drivers in frontal crashes, the analysis examined moderate or greater LEX injury (AIS 2+) in two datasets. Logistic regression considered six main effect factors (KAB deployment, BMI, age, sex, belt status, driver compartment intrusion). Eighty-five cases with KAB deployment from the Crash Injury Research and Engineering Network (CIREN) database were supplemented with 8 cases from the International Center for Automotive Medicine (ICAM) database and compared to 289 CIREN non-KAB cases. All cases evaluated drivers in frontal impacts (11 to 1 o’clock Principal Direction of Force) with known belt use in 2004 and newer model year vehicles. Results of the CIREN/ICAM dataset were compared to analysis of a similar dataset from NASS-CDS (5441 total cases, 418 KAB-deployed).

Spine degeneration can lower injury tolerance and influence injury outcomes in vehicle crashes. To date, limited information exists on the effect of age and sex on thoracic spine 3-dimensional geometry. The purpose of this study is to quantify thoracic spinal column and canal geometry using selected geometrical measurement from a large sample of CT scans. More than 33,488 scans were obtained from the International Center for Automotive Medicine database at the University of Michigan under Institutional Review Board approval (HUM00041441). The sample consisted of CT scans obtained from 31,537 adult and 1,951 pediatric patients between the ages of 0 to 99 years old. Each scan was processed semi-automatically using custom algorithms written in MATLAB (The Math Works, Natick, MA). Five geometrical measurements were collected including: 1) maximum spinal curvature depth (D), 2) T1-to-T12 vertical height (H), 3) Kyphosis Index (KI), 4) kyphosis angle, and 5) spinal canal radius.

Crash safety researchers have an increased concern regarding the decreased thoracic deflection and the contributing injury causation factors among the elderly population. Sternum fractures are categorized as moderate severity injuries, but can have long term effects depending on the fragility and frailty of the occupant. Current research has provided detail on rib morphology, but very little information on sternum morphology, sternum fracture locations, and mechanisms of injury. The objective of this study is two-fold (1) quantify sternum morphology and (2) document sternum fracture locations using computed tomography (CT) scans and crash data. Thoracic CT scans from the University of Michigan Hospital database were used to measure thoracic depth, manubriosternal joint, sternum thickness and bone density. The sternum fracture locations and descriptions were extracted from 63 International Center for Automotive Medicine (ICAM) crash cases, of which 22 cases had corresponding CT scans.

The purpose of this study was to use detailed medical information to evaluate thoracic injuries in elderly patients in real world frontal crashes. In this study, we used analytic morphomics to predict the effect of torso geometry on rib fracture, a major source of injury for the elderly. Analytic morphomics extracts body features from computed tomography (CT) scans of patients in a semi-automated fashion. Thoracic injuries were examined in front row occupants involved in frontal crashes from the International Center for Automotive Medicine (ICAM) database. Among these occupants, two age groups (age < 60 yr. [Nonelderly] and age ≥ 60 yr. [Elderly]) who suffered severe thoracic injury were analyzed. Regression analyses were conducted to investigate injury outcomes using variables for vehicle, demographics, and morphomics. Compared to the nonelderly group, the elderly group sustained more rib fractures.

This paper considers an application of reference governor (RG) to automotive diesel aftertreatment temperature control. Recently, regulations on vehicle emissions have become more stringent, and engine hardware and software are expected to be more complicated. It is getting more difficult to guarantee constraints in control systems as well as good control performance. Among model-based control methods that can directly treat constraints, this paper focuses on the RG, which has recently attracted a lot of attention as one method of model prediction-based control. In the RG, references in tracking control are modified based on future prediction so that the predicted outputs in a closed-loop system satisfy the constraints. This paper proposes an online RG algorithm, taking account of the real-time implementation on engine embedded controllers.

The human body changes as it becomes older. The automotive safety community has been interested in understanding the effect of aging on restraint performance. Recent research has been focused on assessing the structural and material changes associated with age. In this study, structural tissue distribution was determined using the computed tomography (CT) scan data of more than 19,000 patients, aged 16 and up. The data consisted of subcutaneous fat cross-sectional area, visceral fat cross-sectional area, and trabecular bone density taken at each vertebral level. The data was quantified as a function of five age groups with the youngest group defined as 16-29 years old and the oldest group as 75 and up. An additional analysis stratified on gender was carried out. Overall, visceral fat increased with age.

This study investigates the performance of a 3-point restraint system incorporating an inflatable shoulder belt with a nominal 2.5-kN load limiter and a non-inflatable lap belt with a pretensioner (the “Airbelt”). Frontal impacts with PMHS in a rear seat environment are presented and the Airbelt system is contrasted with an earlier 3-point system with inflatable lap and shoulder belts but no load-limiter or pretensioners, which was evaluated with human volunteers in the 1970s but not fully reported in the open literature (the “Inflataband”). Key differences between the systems include downward pelvic motion and torso recline with the Inflataband, while the pelvis moved almost horizontally and the torso pitched forward with the Airbelt. One result of these kinematic differences was an overall more biomechanically favorable restraint loading but greater maximum forward head excursion with the Airbelt.

This paper reports on a study that examines the effect of shoulder belt load limiters and pretensioners as well as crash and occupant factors that influence upper torso harm in real-world frontal crashes. Cases from the University of Michigan International Center for Automotive Medicine (ICAM) database were analyzed. Additional information was used from other databases including the National Highway Traffic Safety Administration (NHTSA) New Car Assessment Program (NCAP), the Insurance Institute for Highway Safety (IIHS), the National Automotive Sampling System - Crashworthiness Data System (NASS-CDS), and patient data available from the University of Michigan Trauma Center. The ICAM database is comprised of information from real-world crashes in which occupants were seriously injured and required treatment at a Level 1 Trauma Center.

The objective of the current study was to provide a comprehensive characterization of human biomechanical response to whole-body, lateral impact. Three approximately 50th-percentile adult male PMHS were subjected to right-side pure lateral impacts at 4.3 ± 0.1 m/s using a rigid wall mounted to a rail-mounted sled. Each subject was positioned on a rigid seat and held stationary by a system of tethers until immediately prior to being impacted by the moving wall with 100 mm pelvic offset. Displacement data were obtained using an optoelectronic stereophotogrammetric system that was used to track the 3D motions of the impacting wall sled; seat sled, and reflective targets secured to the head, spine, extremities, ribcage, and shoulder complex of each subject. Kinematic data were also recorded using 3-axis accelerometer cubes secured to the head, pelvis, and spine at the levels of T1, T6, T11, and L3. Chest deformation in the transverse plane was recorded using a single chestband.

Side impact field crashes from the University of Michigan Crash Injury Research and Engineering Network (UM CIREN) database were studied in detail. These cases involved seriously injured occupants that spanned 1997 - 2006 model year vehicles. Specific injury risks are not presented because the database used was populated only with occupants requiring treatment at a Level 1 Trauma Center. This study analyzes side impact collisions for AIS ≥ 3 injury patterns in crash configuration, injury contact locations, gender and by age. Field crashes were also categorized into those that represent existing standard side impact laboratory test methods. Over half of the cases were identified as collisions into the passenger compartment with occupants seated on the near side of the vehicle closest to the impact, which is consistent with current standard laboratory tests. The next two largest categories involved either far-side occupants or impacts primarily centered onto the engine compartment.

This study evaluated the response of restrained post-mortem human subjects (PMHS) in 40 km/h frontal sled tests. Eight male PMHS were restrained on a rigid planar seat by a custom 3-point shoulder and lap belt. A video motion tracking system measured three-dimensional trajectories of multiple skeletal sites on the torso allowing quantification of ribcage deformation. Anterior and superior displacement of the lower ribcage may have contributed to sternal fractures occurring early in the event, at displacement levels below those typically considered injurious, suggesting that fracture risk is not fully described by traditional definitions of chest deformation. The methodology presented here produced novel kinematic data that will be useful in developing biofidelic human models.

No experimental data exist quantifying the force-deformation behavior of the pediatric chest when subjected to non-impact, dynamic loading from a diagonal belt or a distributed loading surface. Kent et al., (2006) previously published juvenile abdominal response data collected using a porcine model. This paper reports on a series of experiments on a 7-year-old pediatric post-mortem human subject (PMHS) undertaken to guide the scaling of existing adult thoracic response data for application to the child and to assess the validity of the porcine abdominal model. The pediatric PMHS exhibited abdominal response similar to the swine, including the degree of rate sensitivity. The upper abdomen of the PMHS was slightly stiffer than the porcine behavior, while the lower abdomen of the PMHS fit within the porcine corridor. Scaling of adult thoracic response data using any of four published techniques did not successfully predict the pediatric behavior.

Rear seat adult occupant protection is receiving increased attention from the automotive safety community. Recent anthropomorphic test device (ATD) studies have suggested that it may be possible to improve kinematics and reduce injuries to rear seat occupants in frontal collisions by incorporating shoulder-belt force-limiting and pretensioning (FL+PT) technologies into rear seat 3-point belt restraints. This study seeks to further investigate the feasibility and potential kinematic benefits of a FL+PT rear seat, 3-point belt restraint system in a series of 48 kmh frontal impact sled tests (20 g, 80 ms sled acceleration pulse) performed with post mortem human surrogates (PMHS). Three PMHS were tested with a 3-point belt restraint with a progressive (two-stage) force limiting and pretensioning retractor in a sled buck representing the rear seat occupant environment of a 2004 mid-sized sedan.

This study presents a detailed comparison of internally and externally measured chest deflections resulting from eight tests conducted on three male post mortem human subjects. A hydraulically driven shoulder belt loaded the anterior thorax under a fixed spine condition while displacement data were obtained via a high-speed 16-camera motion capture system (VICON MX™). Comparison of belt displacement and sternal displacement measured at the bone surface provided a method for quantifying effective change in superficial soft tissue depth at the mid sternum under belt loading. The relationship between the external displacement and the decrease in the effective superficial tissue depth was found to be monotonic and nonlinear. At 65 mm of mid-sternal posterior displacement measured externally, the effective thickness of the superficial tissues and air gap between the belt and the skin had decreased by 14 mm relative to the unloaded state.

This paper describes the injuries generated during dynamic belt loading to a porcine model of the 6-year-old human abdomen, and correlates injury outcomes with measurable parameters. The test fixture produced transverse, dynamic belt loading on the abdomen of 47 immediately post-mortem juvenile swine at two locations (upper/lower), with penetration magnitudes ranging from 23% – 65% of the undeformed abdominal depth, with and without muscle tensing, and over a belt penetration rate range of 2.9 m/s – 7.8 m/s. All thoracoabdominal injuries were documented in detail and then coded according to the Abbreviated Injury Scale (AIS). Observed injuries ranged from AIS 1 to AIS 4. The injury distribution matched well the pattern of injuries observed in a large sample of children exposed to seatbelt loading in the field, with most of the injuries in the lower abdomen.

Very little experimental research has focused on the kinematics, dynamics, and injuries of rear-seated occupants. This study seeks to develop a baseline response for rear-seated post mortem human surrogates (PMHS) in frontal crashes. Three PMHS sled tests were performed in a sled buck designed to represent the interior rear-seat compartment of a contemporary midsized sedan. All occupants were positioned in the right-rear passenger seat and subjected to simulated frontal crashes with an impact speed of 48 km/h. The subjects were restrained by a standard, rear seat, 3-point seat belt. The response of each subject was evaluated in terms of whole-body kinematics, dynamics, and injury. All the PMHS experienced excessive forward translation of the pelvis resulting in a backward rotation of the torso at the time of maximum forward excursion.

Traumatic aortic rupture (TAR) accounts for a significant mortality in automobile crashes. A numerical method by means of a mesh-based code coupling is employed to elucidate the injury mechanism of TAR. The aorta is modeled as a single-layered thick wall composed of two families of collagen fibers using an anisotropic strain energy function with consideration of viscoelasticity. A set of constitutive parameters is identified from experimental data of the human aorta, providing strict local convexity. An in vitro aorta model reconstructed from the Visible Human dataset is applied to the pulsatile blood flow to establish the references of mechanical quantities for physiological conditions. A series of simulations is performed using the parameterized impact pulses obtained from frontal sled tests.

Injury to the thorax is the predominant cause of fatalities in crash-involved automobile occupants over the age of 65, and many elderly-occupant automobile fatalities occur in crashes below compliance or consumer information test speeds. As the average age of the automotive population increases, thoracic injury prevention in lower severity crashes will play an increasingly important role in automobile safety. This study presents the results of a series of sled tests to investigate the thoracic deformation, kinematic, and injury responses of belted post-mortem human surrogates (PMHS, average age 44 years) and frontal anthropomorphic test devices (ATDs) in low-speed frontal crashes. Nine 29 km/h (three PMHS, three Hybrid III 50th% male ATD, three THOR-NT ATD) and three 38 km/h (one PMHS, two Hybrid III) frontal sled tests were performed to simulate an occupant seated in the right front passenger seat of a mid-sized sedan restrained with a standard (not force-limited) 3-point seatbelt.