Browse Topic: Neck

Items (464)

A Methodology to Evaluate Unrestrained Torso Neck Braces for Near Vertex Impacts

08/22/2024

The advent of neck braces for the helmeted motorcycle rider has introduced a pertinent research question: To what extent do they reduce measures related to the major mechanism of neck injury in unrestrained torso accidents, i.e., compression flexion (CF)? This question requires a suitable method of testing and evaluating the measures for a load case resulting in the required mechanism. This study proposes a weighted swinging anvil striking the helmeted head of a supine HIII ATD by means of a near vertex impact with a low degree of anterior head impact eccentricity to induce CF of the neck. The applied impact was chosen for the baseline (no neck brace) so that the upper and lower neck axial forces approached injury assessment reference values (IARV). The head impact point evaluated represents those typically associated with high-energy burst fractures occurring within the first 20 ms, with possible secondary disruption of posterior ligaments. The proposed test can be used to evaluate

de Jongh, Cornelis U., Basson, Anton H., Knox, Erick H., Leatt, Christopher J.

Seatback Failures and Human Tolerance in Severe Rear Impacts

2024-26-0003

01/16/2024

Seatback and head restraints are the primary restraining devices in rear-impact collisions. The seatback failures expose front seat occupants to dive deep into the rear compartment survival space. Furthermore, it allows the occupants to get in a position with lower spinal tolerance to the impact direction. This paper employs sled tests to demonstrate the dangers of seatback failures in severe rear impact by allowing the occupants to orient their spine in its lowest tolerance zone to the impact direction. Furthermore, the sled test shows the potential of head pocketing phenomena and torso augmentation producing compressive cervical spine loading enough to cause first-order neck buckling. Finally, the results of collapsing seatback dynamics are compared to the strong seatback performance by conducting a similar test with a strong ABTS seatback. The study demonstrates that the strong seatbacks in severe rear impacts produce favorable outcomes while keeping the occupant in their higher

Thorbole, Chandrashekhar

Virtual Reality Based Study on Pre-Impact Position of Auto Rickshaw Driver

2023-28-0118

11/10/2023

The role of Virtual Reality (VR) platform for experimental studies to mitigate severe injuries is known. A Virtual Reality (VR) module was developed to provide an Indian auto-rickshaw driver experience using commercially available Oculus Quest 2 VR headset. A Driver Behaviour Questionnaire (DBQ) was developed and a study carried out among 20 auto-rickshaw drivers in Thanjavur, India. The DBQ questions provided data to shortlist the most likely near crash experiences among the surveyed drivers. A virtual reality environment was created using UNITY HUB software for one selected scenario from the DBQ survey analysis. A group of 10 volunteers to experience the event using VR gear in the biomechanical laboratory with reflective markers fixed on the body joints of the volunteers to obtain corresponding joint angles in the Neck, Lumbar, Shoulder, Hip, and Knee regions. This study identified various pre-crash reactions from drivers and compared them to the normal driving posture to determine

S, Ragul, G, Sundhareswaran, Sankarasubramanian, Hariharan, Prasanna, Selva, Vijayaraghavan, Sriram

Summary of Poster Abstracts

09-11-02-0022

09/20/2023

Eighteen research posters were prepared and presented by student authors at the 18th Annual Injury Biomechanics Symposium. The posters covered a wide breadth of works-in-progress and recently completed projects. Topics included a variety of body regions and injury scenarios such as: Head: Defining the mass, center of mass, and anatomical coordinate system of the pig head and brain; the influence of friction on oblique helmet testing; validation of an in-ear sensor for measuring head impact exposure in American football Neck and spine: Design of paramedic mannequin neck informed by adult passive neck stiffness and range of motion data; identifying injury from flexion-compression loading of porcine lumbar intervertebral disc Thorax: Tensile material properties of costal cartilage perichondrium; finite element models of both an ovine thorax and adipose tissue for high-rate non-penetrating blunt impact Pelvis: Injurious pelvis deformation in high-speed rear-facing frontal impacts Lower

Mueller, Becky, Bautsch, Brian, Mansfield, Julie

Comparison of Head, Neck, and Chest Injury Risks between Front- and Rear-Seated Hybrid III 50th-Percentile Male ATDs in Matched Frontal NCAP Tests

09-12-01-0001

09/19/2023

The objective of this study was to compare head, neck, and chest injury risks between front and rear-seated Hybrid III 50th-percentile male anthropomorphic test devices (ATDs) during matched frontal impacts. Seven vehicles were converted to rear seat test bucks (two sedans, three mid-size SUVs, one subcompact SUV, and one minivan) and then used to perform sled testing with vehicle-specific frontal NCAP acceleration pulses and a rear seated (i.e., second row) Hybrid III 50th male ATD. Matched front seat Hybrid III 50th male ATD data were obtained from the NHTSA Vehicle Crash Test Database for each vehicle. HIC15, Nij, maximum chest acceleration, and maximum chest deflection were compared between the front and rear seat tests, as well as between vehicles with conventional and advanced three-point belt restraint systems in the rear seat. Additionally, a modified version of the NCAP frontal star rating was calculated for the front and rear seat tests. All injury metrics, except for chest

Bianco, Samuel T., Albert, Devon L., Guettler, Allison J., Hardy, Warren N., Kemper, Andrew R.

User’s Manual for the Small Adult Female Hybrid III Test Dummy

J2862_202305 (Current)

05/22/2023

This user’s manual covers the small adult female Hybrid III test dummy. It is intended for technicians who work with this device. It covers the construction and clothing, disassembly and reassembly, available instrumentation, external dimensions and segment masses, as well as certification and inspection test procedures. It includes instructions for safe handling of the instrumented dummy, repairing dummy flesh, and adjusting the joints throughout the dummy

Dummy Testing and Equipment Committee

Hybrid III Ten-Year Old Child Dummy User’s Manual

J2858_202305 (Current)

05/01/2023

This user's manual covers the Hybrid III 10-year old child test dummy. The manual is intended for use by technicians who work with this test device. It covers the construction and clothing, assembly and disassembly, available instrumentation, external dimensions and segment masses, as well as certification and inspection test procedures. It includes guidelines for handling accelerometers, guidelines for flesh repair, and joint adjustment procedures. Finally, it includes drawings for some of the test equipment that is unique to this dummy

Dummy Testing and Equipment Committee

ES2re, WS50M, and Human Body Models in Far-Side Pole Impacts

2023-01-0558

04/11/2023

Driver oblique far-side sled impacts were simulated with three surrogates. The EuroSID side impact dummy with rib extension (ES2re), the WorldSID side impact 50th percentile male dummy (WS50M), and the Global Human Body Modeling Consortium’s 50th percentile male human body (GHBM) models. The versions of the surrogates’ models were 7.0, 7.5.1, and 5.0, respectively. Surrogates were seated in the front left driver seat in a virtual generic crossover sled environment. The Finite Element (FE) based environment consisted of a driver seat, a center console, and a passenger seat. Two restraint systems were considered for each surrogate: belt only (BO) and belt plus a generic seat-mounted far-side impact airbag (BB). Surrogates were restrained using a 3-point belt that has a digressive shoulder force load limiter, and retractor, and anchor pretensioners. The far-side airbag used was a 37-liter in volume and has two chambers. Surrogate head excursions and injury indices for each surrogate were

El-Jawahri, Raed E.

Development of a Neck Finite Element Model with Active Muscle Force for the THOR-50M Numerical Dummy

2023-01-0002

04/11/2023

With the development of active safety technology, effort has gradually shifted to preventing or minimizing car crashes. Automatic Emergency Braking Technology (AEB) can avoid accidents by warning and even automatic braking, but there is a contradiction between the accompanying occupant out-of-position and traditional passive safety design. In addition, the 2025 version of C-NCAP plans to add neck injury assessment requirements for AEB [1]. In order to study the kinematic response of the occupant's neck under AEB, a neck finite element model with active muscle force is established in this paper. Firstly, the open-source THOR-50M neck geometric model is used for finite element discretization. Secondly, the neck FE model of THOR-50M is verified through the qualification procedure of the NHTSA standard. Thirdly, according to the geometric features of human neck muscles in Zygote Body database, the neck muscle parameters are preliminarily determined. Finally, the neck muscle parameters are

Wu, Xiaofan, Jiang, Binhui, Bai, Zhonghao, Zhang, Guanjun

Development and Calibration of the Large Omnidirectional Child ATD Head and Neck Complex Finite Element Model

2023-01-0557

04/11/2023

The National Highway Traffic Safety Administration (NHTSA) has developed the Large Omnidirectional Child (LODC) Anthropomorphic Test Device (ATD) to improve the biofidelity of the currently available Hybrid III 10-year-old (HIII-10C) ATD. The improvements of the LODC over the HIII-10C include changes in sub-assemblies such as the head and neck, where the LODC head is a redesigned HIII-10C head with pediatric mass properties and the neck has a modified atlanto-occipital joint to replicate observations made from human specimens. The current study focuses on developing a dynamic, nonlinear finite element (FE) model of the LODC ATD head and neck complex. The FE mesh is generated using 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 initial and boundary conditions are defined to replicate the neck flexion experimental tests. Next, an inverse method is

Yang, Peiyu, Katangoori, Divya Reddy, Noll, Scott

Evaluation of Drivers of Very Large Pickup Trucks: Size, Seated Height and Biomechanical Responses in Drop Tests

2023-01-0649

04/11/2023

This study focused on occupant responses in very large pickup trucks in rollovers and was conducted in three phases. Phase 1 - Field data analysis: In a prior study [9], 1998 to 2020 FARS data were analyzed; Pickup truck drivers with fatality were 7.4 kg heavier and 4.6 cm taller than passenger car drivers. Most pickup truck drivers were males. Phase 1 extended the study by focusing on the drivers of very large pickup trucks. The size of 1999-2016 Ford F-250 and F-350 drivers involved in fatal crashes was analyzed by age and sex. More than 90% of drivers were males. The average male driver was 179.5 ± 7.5 cm tall and weighed 89.6 ± 18.4 kg. Phase 2 – Surrogate study: Twenty-nine male surrogates were selected to represent the average size of male drivers of F-250 and F-350s involved in fatal crashes. On average, the volunteers weighed 88.6 ± 5.2 kg and were 180.0 ± 3.2 cm tall with a 95.2 ± 2.2 cm seated height. The volunteers were lap-shoulder belted in the driver seat of a 2002 Ford F

Burnett, Roger, Parenteau, Chantal, Vogler, Michelle, Toomey, Daniel, Orlowski, Kenneth, Krishnaswami, Ram

Lumbar Flexion Test Procedure for the Hybrid III 50th Male Dummy

J3074_202303 (Current)

03/20/2023

This procedure establishes a recommended practice for performing a lumbar flexion test to the Hybrid III 50th male anthropomorphic test device (ATD or crash dummy). This test was created to satisfy the demand from industry to have a certification test which characterizes the lumbar without interaction of other dummy components. In the past, there have not been any tests to evaluate the performance of Hybrid III 50th lumbar

Dummy Testing and Equipment Committee

Performance Standards for Side-Facing Seats in Civil Rotorcraft, Transport Aircraft, and General Aviation Aircraft

AS8049/1B (Current)01/20/2023

This SAE Aerospace Standard (AS) defines Minimum Performance Standards (MPS), qualification requirements, and minimum documentation requirements for side-facing seats in civil rotorcraft, transport aircraft, and general aviation aircraft. The goal is to achieve comfort, durability, and occupant protection under normal operational loads and to define test and evaluation criteria to demonstrate occupant protection when a side-facing seat/occupant/restraint system is subjected to statically applied ultimate loads and to dynamic test conditions set forth in Title 14, Code of Federal Regulations (CFR) Part 23, 25, 27, or 29. While this document addresses system performance, responsibility for the seating system is divided between the seat supplier and the installation applicant. The seat supplier’s responsibility consists of meeting all the seat system performance requirements and obtaining and supplying to the installation applicant all the data prescribed by this document. The

Aircraft Seat Committee

Development of a New Human Thoracic Equivalent Model during Frontal Impact

09-11-02-0007

01/13/2023

Human thoracic injury under frontal collisions is an inevitable problem in vehicle safety research. Compared with the Multiple Rigid-Body Models (MRBMs) and Finite Element Human Body Models (FEHBMs), Mathematical Equivalent Models (MEMs) can not only provide important data but also improve the research efficiency. The current thoracic MEMs usually adapted the mechanical isolation method to isolate the thorax from the human body; therefore, the effects of the head, neck, and lower body internal organs on the mechanical responses of the thorax are not considered. In this article, a new thoracic MEM, named as Improved Consistent Lobdell Model (ICLM), is developed based on the concentrated mass-spring-damping system to consider the energy absorbed by the deformation of the internal soft tissue and the motion hysteresis of the head, neck, and lower body. Thorax equivalent stiffness curve predicted by the ICLM has a good fit with the corridor obtained by the Post-Mortem Human Subjects (PMHS

Liu, Zhixin, Zheng, Hong, Ma, Weijie

User’s Manual for the 50th Percentile Male Hybrid III Dummy

J2856_202211 (Current)

11/22/2022

The purpose of this document is to provide the user with the procedures needed to properly assemble and disassemble the 50th percentile male Hybrid III dummy, certify its components and verify its mass and dimensions. Also within this manual are guidelines for handling accelerometers, repairing flesh and setting joints

Dummy Testing and Equipment Committee

Instrumentation for Impact Test Part 1 - Electronic Instrumentation

J211/1_202208 (Current)08/19/2022

Safety Test Instrumentation Standards Committee

Low Speed Thorax Impact Test Procedure for the HIII 50th Male Dummy

J2779_202206 (Current)

06/29/2022

Dummy Testing and Equipment Committee

Low Speed Thorax Impact Test Procedure for the HIII5F Dummy

J2878_202206 (Current)

06/09/2022

This procedure establishes a recommended practice for performing a Low Speed Thorax Impact Test to the Hybrid III Small Female Anthropomorphic Test Device (ATD or crash dummy). This test was created to satisfy the demand by the industry to have a certification test which results in peak chest deflection similar to current full vehicle, frontal impact tests. An inherent problem exists with the current certification procedure because the normal (6.7 m/s) thorax impact test has test results for peak chest deflection that are greater than those currently seen in full vehicle, frontal tests. The intent of this document is to develop a low speed thorax certification procedure for the H-III5F dummy with a 3.0 m/s impact similar to the SAE J2779 procedure for the H-III50M dummy

Dummy Testing and Equipment Committee

Biomechanical Responses of the THOR-AV ATD in Rear Facing Test Conditions

2022-01-0836

03/29/2022

The THOR-AV dummy is a modified THOR dummy being developed for occupant safety testing in upright and reclined seating postures. The dummy has a new neck with improved biofidelity in rear impact, a pelvis/abdomen/lumbar design to improve seating posture, and a pelvis anthropometry that mimics human submarining responses for reclined seat testing. The dummy was evaluated against postmortem human subject (PMHS) corridors in rearward facing impact conditions (56 km/h impact speed, 38g acceleration) in both 25° and 45° seatback configurations. Biofidelity Ranking System (BRS) scores were calculated in accordance with NHTSA’s latest calculation algorithm. The BRS scores for THOR-AV seat loading are 1.58 (“good” biofidelity) and 2.94 (“marginal” biofidelity) for the 25° and 45° configurations respectively. The BRS scores for THOR-AV occupant responses are 1.95 and 1.38 for the 25° and 45° configurations respectively, both corresponding to “good” biofidelity. From the evaluation, the dummy

Wang, Zhenwen Jerry

Development of Biomechanical Computational Models of Six-Year-Old Child Occupant with Different Sitting Postures and Application in the Study of Whiplash Injuries

2022-01-0869

03/29/2022

With the development of intelligent cockpit, child occupants will engage in traffic operation in various sitting postures. Therefore, studying the mechanism and risk of whiplash injury of child occupants with different sitting postures has important application value for the research and development of child restraint system. In this study, the 120° and 135° sitting postures of six-year-old child occupant were developed based on the validated 105° sitting posture finite element model with detailed anatomical structure. The whiplash test in Euro NCAP was reconstructed to evaluate the influence of sitting posture angle on the risk of whiplash injury. In the three groups of simulation experiments, the Upper Neck Tension (Fz) was far less than the higher limit of Euro NCAP evaluation although the Fz value increased as the upper torso angle increases. However, the Upper Neck Shear (Fx) and Neck Injury Criterion (NIC) values from the 105° sitting posture exceeded the higher limit of Euro

Li, Haiyan, Wang, Yanxin, He, Lijuan, Lv, Wenle, Cui, Shihai, Ruan, Jesse Shijie

Multi-Objective Optimization Study on Ligament Characteristics of Neck Finite Element Model

2022-01-0862

03/29/2022

This paper proposes a new method to improve the fit between the neck finite element calculation results and the experimental data through multi-objective optimization of cervical ligament parameters. By refining a previously established finite element model of the neck and improving the fineness of vertebrae and other structures, a new finite element model of the neck was established. The new model adopts the same material property parameters as the previous model. We performed many simulation calculations, each time only one ligament in the model was removed, leaving other structures unchanged. By observing the changes in the angle of the neck joints in the neck torsion experiment of the model before and after the ligament was removed, the influence of the ligament on the model was obtained. The six ligaments with the largest contribution are selected, and their laxity is optimized for multi-objective research, and the optimal solution for the laxity of the selected ligaments is

Yang, Shuaijun, Song, Xuewei, Wang, Peng, Wang, Nan

The Role of Three-Point Restraints for Occupants in Moderate Severity Frontal Collisions

2022-01-0845

03/29/2022

Field accident data and vehicle crash and sled testing indicate that occupant kinematics, loading, and associated injury risk generally increase with crash severity. Further, these data demonstrate that the use of restraints, such as three-point belts, provides mitigation of kinematics and reduction in loading and injury potential. This study evaluated the role of seat belts in controlling occupant kinematics and reducing occupant loading in moderate severity frontal collisions. Frontal tests with belted and unbelted anthropomorphic test devices (ATDs) in the driver and right front passenger seats were performed at velocity changes (delta-Vs) of approximately 19 kph (12 mph) and 32 kph (20 mph) without airbag deployment. At the lower-moderate severity (19 kph), motion of the belted ATDs was primarily arrested by seat belt engagement, while motion of the unbelted ATDs was primarily arrested by interaction with forward vehicle structures. Occupant loading and injury risk was generally

Isaacs, Jessica L., George, Juff, Campolettano, Eamon, Cutcliffe, Hattie, Miller, Bruce

Seatback Strength and Its Effect on In-Position and Out-of-Position ATD Loading in High-Speed Rear Impact Sled Tests

2022-01-0856

03/29/2022

Vehicle rear structure stiffness has increased as a result of the requirements in the FMVSS 301R, which has also corresponded to an increase in front-row seat strength. This study evaluates the structural behavior and occupant response associated with production-level seats equipped with body-mounted D-rings, and very stiff all-belt-to-seat (ABTS) in a group of 12 deceleration sled tests. A double-haversine pulse with approximately 100-msec duration was used for all tests, with peak accelerations of approximately 19 g for the 40 km/h (25 mph) tests and peak accelerations of 28 g for the 56 km/h (35 mph) test. This generic pulse was designed to represent a severe rear impact crash involving vehicles with stiffer rear structures. The tests compared occupant responses and resulting structural deformation of an original equipment manufacturer (OEM) production-level driver seat from a pickup and a very stiff modified ABTS. Both seating systems were equipped with dual recliners. Various

Croteau, Jeffrey, Toney-Bolger, Megan, Isaacs, Jessica L., Shurtz, Ben, Zolock, John

Human Head and Neck Kinematics during Autonomous and Human Braking in Three Initial Head Positions

09-10-02-0007

03/28/2022

Whiplash injuries resulting from vehicle collisions are still a significant socio-economic issue across the world. Years of research has resulted in the development of injury criteria, restraint systems and a deeper understanding of the injury mechanism. However, some grey areas remain and, in the context of the increasing automation of vehicles, one can wonder how the injury mechanisms may change due to changes in collision forces or directions. This article presents an experiment with ten volunteers subjected to two braking modes, including automated braking preceded by an alarm warning or robot human braking, in three different initial head positions: forward facing, lateral rotation and flexion rotation. The volunteers were equipped with inertial measurement units to record their head and neck dynamics. Results show that the initial position of volunteers implies differences in the volunteer head dynamics. Also, the auditory alarm emitted prior to the emergency braking may have

Mackenzie, Jamie, Dutschke, Jeffrey, Di Loreto, Cédric, Forrest, Matthew, Van Den Berg, Andrew, Merienne, Frédéric, Chardonnet, Jean-Rémy, Sandoz, Baptiste

Muscle Activation Affects Kinematic Response and Injury Risk in Non-Traditional Oblique Impact Scenarios Assessed with a Head and Neck Finite Element Model

09-10-02-0008

03/23/2022

Detailed finite element human body models (HBMs), and neck models (NMs) in particular, have been used to assess response and injury risk with a focus on frontal, lateral, and rear impact conditions. Although HBMs have successfully predicted kinematics and the importance of active muscle in simple loading conditions, they have generally not been assessed for more complex loading conditions such as non-traditional oblique loading that may be encountered in future vehicles equipped with automated driving systems. In this study, a contemporary NM was assessed using oblique human volunteer sled test data. Average head and first thoracic vertebra kinematics were determined from the volunteer tests and applied as a boundary condition to the NM. An open-loop co-contraction muscle activation scheme with four activations times within reported human limits (50, 75, 100, no activation) was used to investigate the effect on response and potential for injury risk. The T1 and head kinematics from 45

Barker, Jeffrey, Cronin, Duane S.

Reconstruction of an Auto-Rickshaw Frontal Crash using FE Simulation with Validation using Captured Crash Video from India

2021-28-0257

10/01/2021

The three-wheeled "Auto-Rickshaws" [Auto] plays a significant role in road transportation, especially in India. The crash safety and reconstruction studies have been widely used in four-wheelers, whereas the availability of such data for Auto was limited. In recent times, accident data processing from available videos is being utilized to observe the crash scenario. The crash parameters can be given as inputs to the crash analysis. This paper focuses on the process the real-world accident data and study crash characteristics. With limitation in the availability of detailed injuries post-crash, the study was restricted to reconstructing crash kinematics and estimating indicative injuries to the driver. The source of video data is videos of crash available in public domains like YouTube. PYTHON video processing tool has been used to process the set of real-world accident video data. Object detection, Pixel per meter computation and object tracking are the significant steps to process the

S, Ragul, Sankarasubramanian, Hariharan, Kondaveeti, N S V Nikas, Yadav, Pandugayala Nithin

Robotic Neck Brace Can Help Analyze the Impact of Cancer Treatment

TBMG-4002910/01/2021

A new robotic neck brace from researchers at Columbia Engineering and their colleagues at Columbia’s department of otolaryngology may help doctors analyze the impact of cancer treatments on the neck mobility of patients and guide their recovery

Applicability of Neck Injury Criteria Critical Intercepts for Human Body Finite Element Models

09-09-02-000808/25/2021

The critical intercepts used for the Neck Injury Criterion (Nij) have not been assessed in computational human body models. Under matched-pair conditions, the response of the head-neck complex was compared between the Livermore Software Technology Corporation (LSTC) Hybrid III (HIII) and Global Human Body Models Consortium’s (GHBMC) 50th percentile, detailed male occupant (M50-O) models. The head and neck of the M50-O and HIII were subjected to the dummy performance calibration test procedure for flexion and extension. As a nominal condition, the HIII model met all calibration specifications. Operationalization of the M50-O’s initial position was defined by equivalent head CG location to the HIII and subsequently compared at nominal, ±10%, ±20%, and ±30% of pendulum displacement. Kinematics of the head CG, forces and moments of the upper neck, and changes in neck angle were post processed and compared between the models. The sagittal velocity of the head CG was found to be greater for

Johnson, Dale, Devane, Karan, Koya, Bharath, Gayzik, F. Scott

Assessment of Acclimation of 5th Percentile Female and 50th Percentile Male Volunteer Kinematics in Low-Speed Frontal and Frontal-Oblique Sled Tests

09-09-01-000105/12/2021

In order to accurately represent the response of live occupants during pre-crash events and frontal crashes, computational human body models (HBMs) that incorporate active musculature must be validated with appropriate volunteer data that represents a wide range of demographic groups and potential crash conditions. The purpose of this study was to quantify and compare occupant kinematic responses for unaware (relaxed) small female and midsize male volunteers during low-speed frontal and frontal-oblique sled tests across multiple test conditions, while recognizing, assessing, and accounting for potential acclimation effects due to multiple exposures. Six 5th percentile female and six 50th percentile male volunteers were exposed to multiple low-speed frontal and frontal-oblique sled tests on two separate test days. Volunteers experienced one test orientation and two pulse severities (1 g and 2.5 g) on each test day. A Vicon motion capture system was used to quantify the three-dimensional

Chan, Hana, Albert, Devon L., Gayzik, F. Scott, Kemper, Andrew R.

Analysis of Biomechanical Neck-Loading Metrics as a Function of Impact Severity in Low-to-Moderate Speed Rear Impacts: Results from Hybrid III 50th Percentile Anthropomorphic Test Devices

09-08-02-0007

04/14/2021

We model neck loading as a function of impact severity in aligned rear impacts. Neck loading is understood and expected to vary as a function of factors including crash severity, occupant compartment design, and occupant metrics. Within occupant compartment design, seat and restraint characteristics are expected to influence the biomechanical response and occupant kinematics. We investigated the relationship between biomechanical neck-loading metrics and impact severity expressed as speed change (delta-V) by examining 47 low to moderate speed rear-impact crash and sled tests utilizing the Hybrid III (HIII) 50th male Anthropomorphic Test Device (ATD). Our hypothesis was that the relationship between severity expressed as delta-V and the neck metrics examined could be modeled as linear consistent with an understanding that neck loading in a rear impact results from the acceleration of the vehicle. As such, linear regressions were used to fit the dataset and examine the relationship

Chhour, Peter, Hoffman, Austin, McGowan, Joseph C.

Assessment of the 50th Hybrid III Responses in Blunt Rear Impacts to the Torso

2021-01-0919

04/06/2021

Blunt impacts to the back of the torso can occur in vehicle crashes due to interaction with unrestrained occupants, or cargo in frontal crashes, or intrusion in rear crashes, for example. Six pendulum tests were conducted on the back of an instrumented 50th percentile male Hybrid III ATD (Anthropomorphic Test Device) to determine kinematic and biomechanical responses. The impact locations were centered with the top of a 15-cm diameter impactor at the T1 or at T6 level of the thoracic spine. The impact speed varied from 16 to 24 km/h. Two 24 km/h tests were conducted at the T1 level and showed repeatability of setup and ATD responses. The 16 and 24 km/h tests at T1 and T6 were compared. Results indicated greater head rotation, neck extension moments and neck shear forces at T1 level impacts. For example, lower neck extension was 2.6 times and 3.8 times greater at T1 versus T6 impacts at 16 and 24 km/h, respectively. A 24 km/h test at T1 was also conducted with a seatback attached to the

Buckman, Jennifer L., Parenteau, Chantal S., Burnett, Roger, Viano, David C., Andrecovich, Christopher

Evaluation of Rotation Reduction Features in Infant and Extended-Use Convertible Child Restraint Systems during Frontal and Rear Impacts

2020-22-0003

04/02/2021

A correctly used child restraint system (CRS) is associated with a substantial reduction of injury and mortality risks in motor vehicle crashes and epidemiologic data suggests that toddlers are provided greater protection when restrained in a rearward-facing CRS compared to a forward-facing CRS. Some ‘extended-use’ European CRS models can accommodate children up to six years rearward-facing and have a support (load) leg and/or a pair of lower (Swedish) tethers to reduce rotation during frontal and rear impacts, respectively. Laboratory studies have found that a support leg reduces head and neck injury metrics of anthropomorphic test devices (ATDs) younger than three years in rearward-facing CRS models during frontal impacts. The objectives of the current study were to perform sled tests to: (1) evaluate the effects of using a support leg in rearward-facing infant and extended-use convertible CRS models during frontal impacts, (2) evaluate the effects of using a pair of lower tethers in

Patton, Declan A., Belwadi, Aditya N., Maheshwari, Jalaj, Arbogast, Kristy B.

Effect of Simulated Muscle Activation Level on Driver Neck Response in Frontal Motor Vehicle Crashes

2021-01-5008

01/22/2021

Future vehicle design for integrated safety requires an accurate assessment of occupants’ realistic behavior. Active muscle, one of the key reflexive actions engaged by vehicle occupants, is a paucity of research data in the conventional safety assessment program due to muscle absence in mechanical crash dummies. This study seeks to explore how muscle activation level affects the neck kinematics and injury risks in frontal collisions with various impact severities via numerical analysis. A validated Finite Element (FE) vehicle model was employed to generate the crash pulse. A MADYMO baseline model interior space was imported from the FE model. A validated vehicle- driver model, including a driver-side interior compartment and a multi-body active human model, was numerically constructed under the MADYMO environment. A full-factorial matrix, including 102 simulations, was designed. Two influencing parameters, including the whole-body muscle activation level (0-1 with a gradient of 0.2

Deng, Gongxun, Gan, Shun, Chen, Wentao, Zhou, Qing, Peng, Yong, Cui, Taisong, Nie, Bingbing

Metamodel Generation for Frontal Crash Scenario of a Passenger Car

2020-28-0504

09/25/2020

A frontal impact scenario was simulated using a Finite Element Model of a Hybrid III 50th percentile male (LSTC, Livermore CA) along with seatbelt, steering system and driver airbags. The boundary conditions included acceleration pulse to the seat and the outputs including injury measures in terms of Head Injury Criterion (HIC), Normalized Neck Injury Criterion (NIJ) and Chest Severity Index (CSI) were extracted from the simulations. The kinematics of the Hybrid III were validated against the kinematics of post mortem human surrogates (PMHS) available in the literature. Using the validated setup, metamodels were generated by creating a design of varying different parameters and recording the responses for each design. First, the X and Z translation of dummy along the seat is provided as input for which there was no variation in the head injury criterion (HIC). Next, the input pulse to the seat is parameterized along with the seatbelt loading and the results are obtained respectively

Shankar, Hari, Selvaraju, Ragul, Sankarasubramanian, Hariharan

Smart Surgical Microscope

TBMG-3746908/01/2020

Researchers have shown that hyperspectral imaging and artificial intelligence could predict the presence of cancer cells with 80 to 90% accuracy in 293 tissue specimens from 102 head and neck cancer surgery patients. The smart surgical microscope could help surgeons better detect cancer during surgery, reduce operating time, lower medical costs, and save lives. Hyperspectral imaging is noninvasive, portable, and does not require radiation or a contrast agent

A Preliminary Study on the Restraint System of Self-Driving Car

2020-01-1333

04/14/2020

Due to the variation of compartment design and occupant’s posture in self-driving cars, there is a new and major challenge for occupant protection. In particular, the studies on occupant restraint systems used in the self-driving car have been significantly delayed compared to the development of the autonomous technologies. In this paper, a numerical study was conducted to investigate the effectiveness of three typical restraint systems on the driver protection in three different scenarios. It is found that based on the simulation results: (1) All the restraint systems are capable of providing effective protection for the driving driver and the 4-point belt restraint system has advantages due to its better protective effect on the occupant thorax; (2) When the driver is in half-reclining and reclining resting modes, head HIC36, neck Nij and chest compression are about 572.9-1524.3, 0.64-1.47, and 14.7-48.3 mm, respectively; These values are higher than those of a driving driver by 0.2

Jiang, Binhui, Ren, Hongze, Zhu, Feng, Chou, Clifford, Bai, Zhonghao

Innovative Active Head Restraint System in a Car: Safety Assessment with Virtual Human Body Model

2020-01-0979

04/14/2020

The aim of this study is to use numerical simulations for safety assessment of an innovative active head restraint system. This system was developed to protect the head and neck of an occupant in a car without a head airbag during a side impact. Its FE model is created and embedded it in a model of a small car with a side airbag. The dynamics of the head restraint activation are also taken into account. The virtual human body model Virthuman is used to represent occupants. The model is scaled for pre-selected human individuals to cover large numbers of occupants of different sizes. It extends conventional virtual evaluation of new safety designs via existing pre-defined mono-purpose side dummies and their FE models. The benefit of the head restraint system is evaluated in side impact scenarios inspired by the pole tests performed by EuroNCAP. Transversal impacts to a pole at 29 and 32 km/h are considered at 90° and 75° angles from driver and the opposite side. Also, the far side impact

Vychytil, Jan, Hlucha, Jana, Kovar, Ludek, Kostikova, Martina, Moravcova, Pavlina, Bucsuhazy, Katerina

Injury Rates by Crash Severity, Belt Use and Head Restraint Type and Performance in Rear Impacts

2020-01-1223

04/14/2020

This study assesses the exposure distribution and injury rate (MAIS 4+F) to front-outboard non-ejected occupants by crash severity, belt use and head restraint type and damage in rear impacts using 1997-2015 NASS-CDS data. Rear crashes with a delta V <24 km/h (15 mph) accounted for 71% of all exposed occupants. The rate of MAIS 4+F increased with delta V and was higher for unbelted than belted occupants with a rate of 11.7% ± 5.2% and 6.0% ± 1.5% respectively in 48+ km/h (30 mph) delta V. Approximately 12% of front-outboard occupants were in seats equipped with an integral head restraint and 86% were with an adjustable head restraint, irrespective of crash severity. The overall injury rate was 0.14% ± 0.05% and 0.22% ± 0.06%, respectively. It was higher in cases where the head restraint was listed as “damaged”. Thirteen cases involving a lap-shoulder belted occupant in a front-outboard seat in which “damage” to the adjustable head restraint was identified. Review of these cases showed

Parenteau, Chantal, Miller, Bruce, Burnett, Roger

Pedestrian Orientation Estimation Using CNN and Depth Camera

2020-01-0700

04/14/2020

This work presents a method for estimating human body orientation using a combination of convolutional neural network (CNN) and stereo camera in real time. The approach uses the CNN model to predict certain human body keypoints then transforms these points into a 3D space using the stereo vision system to estimate the body orientations. The CNN module is trained to estimate the shoulders, the neck and the nose positions, detecting of three points is required to confirm human detection and provided enough data to translate the points into 3D space

Abughalieh, Karam, Alawneh, Shadi

Occupant Dynamics during Moderate-to-High Speed Rear-End Collisions

2020-01-0516

04/14/2020

Numerous studies have evaluated occupant kinematics and dynamics in “low-speed” rear-end impacts (delta-V ≤ 8 mph). Occupant biomechanics during “moderate-to-high” speed rear impacts (9 ≤ delta-V ≤ 20 mph) has not been thoroughly examined. This study characterized the motions and forces experienced by the head, neck, torso, hip, and left/right femur during these collisions. The publicly available NHTSA rear-end crash test data were examined. More specifically, the FMVSS 301 Fuel System Integrity tests were used. The test procedure involved a 30 mph moving barrier impacting the rear of the vehicles. Instrumented 50th-percentile male (N = 47) or 5th-percentile female (N = 4) Hybrid III ATDs were positioned in the driver seat. Occupant data including head accelerations, upper/lower neck shear and axial forces, upper/lower neck moments, lower neck acceleration, torso accelerations, torso deflection, hip accelerations, and left/right femur axial forces were evaluated and compared to

Atarod, Mohammad

Biomechanics of Passenger Vehicle Underride: An Analysis of IIHS Crash Test Data

2020-01-0525

04/14/2020

Occupant dynamics during passenger vehicle underride has not been extensively evaluated. The present study examined the occupant data from IIHS rear underride crash tests. A total of 35 crash tests were evaluated. The tests were classified as full-width (n = 9), 50% overlap (n = 11), and 30% overlap (n = 15). A 2010 Chevrolet Malibu impacted the rear underride guard of a stationary trailer at 35 mph. Several occupant kinematics and dynamics data including head accelerations, head injury criteria, neck shear and axial forces, neck moments, neck indices, chest acceleration, chest displacement, chest viscous criterion, sternum deflection rate, and left/right femur forces/impulses, knee displacements, tibia axial forces, upper/lower tibia moments, upper/lower tibia indices, and foot accelerations were measured. The vehicle accelerations, delta-Vs, and occupant compartment intrusions were also evaluated. The results indicated that the head and neck injury parameters were positively

Atarod, Mohammad

The Effects of Active and Conventional Head Restraints on Front Seat Occupant Responses in Rear Impacts

2020-01-1217

04/14/2020

This study assesses front seat occupant responses in rear impacts with active head restraints (AHR) and conventional head restraints (CHR) using field accident data and test data from the Insurance Institute for Highway Safety (IIHS). 2003-2015 NASS-CDS data were analyzed to determine injury rates in 1997+ model year seats equipped with AHR and CHR. Results indicated that less than 4% of occupants were in seats equipped with AHR. Crashes of delta-V <24 km/h accounted for more than 70% of all exposed front seat occupants, irrespective of head restraint design. Rear crashes with a delta-V < 24 km/h included 35.6% fewer occupants who sustained a MAIS 1-2 injury overall and 26.4% fewer who sustained a MAIS 1-2 cervical injury in vehicles equipped with AHR compared to CHR. In IIHS 16 km/h rear sled tests, the biomechanical response of an instrumented BioRID was evaluated on seats with AHR and CHR. HIC15 and concussion risk were calculated from head acceleration data. Test data with AHR and

Parenteau, Chantal, Campbell, Ian C., Pasquesi, Stephanie A.

Far Side Impact Injury Threshold Recommendations Based on 6 Paired WorldSID / Post Mortem Human Subjects Tests

2019-22-0005

03/31/2020

Far side has been identified in the literature as a potential cause of numerous injuries and fatalities. Euro NCAP developed a far side test protocol to be performed to assess adult protection. A monitoring phase was undertaken between January 2018 and December 2019, and the far side assessment will become part of the rating for all vehicles launched in 2020 onward. A test buck was developed and 6 paired WorldSID / Post Mortem Human Subjects (PMHS) were subjected to the test protocol proposed by Euro NCAP to contribute to the development of limits. The buck consisted of a rigid seat and a rigid central console covered with 50 mm of Ethafoam TM 180 with a density of 16 kg/m3. The buck was mounted on the sled with an angle of 75° between the X axis of the vehicle and the X axis of the sled. The peak head excursion was compared between PMHS and the WorldSID dummy. It was found reasonably similar. However, the dummy repeatability was found to be poor. Out of 6 tests conducted on 6 PMHS, 2

Petit, Philippe, Trosseille, Xavier, Uriot, Jérome, Poulard, David, Potier, Pascal, Baudrit, Pascal, Compigne, Sabine, Kunisada, Masato, Tsurui, Kenji

Passenger Injury Analysis Considering Vehicle Crash after AEB Activation

2019-22-0023

03/31/2020

Owing to an increasing autonomous emergency braking (AEB) adoption, emergency braking before crash occurs more often than in the case of conventional vehicles. Due to the sudden deceleration in AEB activation, passengers move forward before the crash. To explore how this forward movement affects passenger injury, sled tests are performed with an inclined dummy representing forward displacement. The test shows that a shorter distance between the airbag and passenger results in bigger neck injuries induced by airbag deployment force. A countermeasure is suggested to prevent neck injury in emergency braking situation by reducing deployment force and protrusion

Ko, Seokhoon, Jeong, Garam, Kim, Dohyung, Park, Haekwon, Lee, Kyusang, Jang, Raeick

Head Support Concept to Mitigate Neck Injury for Children Installed Forward Facing in Vehicles

2019-36-010601/13/2020

The slender neck of a 3-year-old child can be serious injured or even lead to child’s death when loaded under frontal impact by the proportionately larger and heavier head. Accordingly with medical recommendations based on latest studies, a 3-year-old child is safer when installed in a rear-facing child seat, but this configuration is not feasible for some vehicles with limited rear space such as superminis, small MPVs and pick-ups when front seats are occupied. This study aims to explore the potential of neck tension (Fz) reduction in 3-year-old dummy installed forward-facing when subjected to three head static restraints (head strap, head support, cervical collar) as well as an overhead shield car seat in order to identify solutions for a device to avoid or mitigate neck injuries. To simulate frontal impacts, a 3-year-old dummy from Q series was installed on a reinforced vehicle body fixed on a sled test equipment where the United Nations R129 pulse was applied. Both head strap and

Ribeiro, Rodrigo da Silva, De Arruda, Antonio Celso Fonseca

Honda ready with new injury-reducing airbag

19AUTP10_0810/01/2019

Starting next year, Honda will begin fitting vehicles with a new, advanced-design passenger-side front airbag that its engineers said is designed to mitigate brain and neck injuries by cradling the head like a baseball in a catcher's mitt. The design is particularly effective, Honda said, for angled impacts or when an occupant is not in optimal position when the crash occurs, reducing rotational acceleration of the head that can traumatize the brain. More than half of all impacts occur at some angle, said Eric Heitkamp, Honda R&D Americas technical leader/principal engineer, crashworthiness, at a media reveal of the new airbag at the company's safety research facility in Raymond, Ohio. Heitkamp said the airbag was developed by the facility's engineers in partnership with restraints supplier Autoliv

Visnic, Bill

Occupant Kinematics and Loading in Low Speed Lateral Impacts

2019-01-1027

04/02/2019

Instrumented human subject and anthropomorphic test device (ATD) responses to low speed lateral impacts were investigated. A series of 12 lateral collisions at various impact angles were conducted, 6 near-side and 6 far-side, with each test using an ATD and one human subject. Two restrained female subjects were utilized, with one positioned in the driver seat and one in the left rear seat. Each subject was exposed to 3 near-side and 3 far-side impacts. The restrained ATD was utilized in both the driver and left rear seats, undergoing 3 near-side and 3 far-side impacts in each position. The vehicle center of gravity (CG) change in velocity (delta-V) ranged from 5.5 to 9.4 km/h (3.4 to 5.8 mph). Video analysis was used for quantification and comparison of the human and ATD motions and interactions with interior vehicle structures. Human head, thorax, and low back accelerations were analyzed. Peak human subject head resultant accelerations ranged from 0.9 to 36.8 g’s. Peak human subject

Furbish, Christopher, Welcher, Judson, Brink, Justin, Jones, Brian, Swinford, Scott, Anderson, Robert

THOR Neck Moment Calculation at Atlanto-Occipital Joint

2019-01-103704/02/2019

In biomechanics research of human neck injuries, the moment for the upper neck was calculated to the Atlanto-Occipital (AO) joint. In this paper, a mathematical method was presented to calculate the neck moment at AO for both Test Device for Human Occupant Restraint (THOR) 50th male and THOR 5th female ATDs in neck flexion, extension and lateral bending directions. Detailed formula was derived according to the mechanical design and how parts functions in the ATD. The constant parameters for both THOR 50th and 5th were provided for the calculation. One THOR-50M neck test data was presented in this paper to illustrate the calculation results

Wang, Zhenwen Jerry

Influence of DISH, Ankylosis, Spondylosis and Osteophytes on Serious-to-Fatal Spinal Fractures and Cord Injury in Rear Impacts

2019-01-1028

04/02/2019

Seats have become stronger over the past two decades and remain more upright in rear impacts. While head restraints are higher and more forward providing support for the head and neck, serious-to-fatal injuries to the thoracic and cervical spine have been seen in occupants with spinal disorders, such as DISH (diffuse idiopathic skeletal hyperostosis), ankylosis, spondylosis and/or osteophytes that ossify the joints in the spine. This case study addresses the influence of spinal disorders on fracture-dislocation and spinal cord injury in rear impacts with relatively upright seats. Nineteen field accidents were investigated where serious-to-fatal injuries of the thoracic and cervical spine occurred with the seat remaining upright or slightly reclined. The occupants were lap-shoulder belted, some with belt pretensioning and cinching latch plate. The occupants were older and had pre-existing disorders of the spine, including DISH, ankylosis, spondylosis and/or osteophytes that ossify the

Viano, David, Parenteau, Chantal, White, Samuel

Comfortable Head and Neck Postures in Reclined Seating for Use in Automobile Head Rest Design

2019-01-040804/02/2019

Little information is available on passenger preferences for posture and support in highly reclined seat configurations. To address this gap, a laboratory study was conducted with 24 adult passengers at seat back angles from 23 to 53 degrees. Passenger preferences for head and neck posture with and without head support were recorded. This paper presents the characteristics of the passengers’ preferred head support with respect to thorax, head, and neck posture

Reed, Matthew, Ebert, Sheila, Jones, Monica

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