Browse Topic: Impact tests

Items (2,294)
The New Car Assessment Program (e.g., US NCAP and EuroNCAP) frontal crash tests are an essential part of vehicle safety evaluations, which are mandatory for the certification of civil means of transport prior to normal road exploitation. The presented research is focused on the behavior of a tubular low-entry bus frame during a frontal impact test at speeds of 32 and 56 km/h, perpendicular to a rigid wall surface. The deformation zones in the bus front and roof parts were estimated using Ansys LS-DYNA and considered such factors as the additional mass (1630 kg) of electric batteries following the replacement of a diesel engine with an electric one. This caused stabilization of the electric bus body along the transverse axis, with deviations decreased by 19.9%. Speed drop from 56 to 32 km/h showed a reduction of the front window sill deformations from 172 to 132 mm, and provided a twofold margin (159.4 m/s2) according to the 30g ThAC criterion of R80. This leads to the conclusion about
Holenko, KostyantynDykha, AleksandrKoda, EugeniuszKernytskyy, IvanRoyko, YuriyHorbay, OrestBerezovetska, OksanaRys, VasylHumeniuk, RuslanBerezovetskyi, SerhiiChalecki, Marek
The integrated vehicle crash safety design provides longer pre-crash preparation time and design space for the in-crash occupant protection. However, the occupant’s out-of-position displacement caused by vehicle’s pre-crash emergency braking also poses challenges to the conventional restraint system. Despite the long-term promotion of integrated restraint patterns by the vehicle manufacturers, safety regulations and assessment protocols still basically focus on traditional standard crash scenarios. More integrated crash safety test scenarios and testing methods need to be developed. In this study, a sled test scenario representing a moderate rear-end collision in subsequence of emergency braking was designed and conducted. The bio-fidelity of the BioRID II ATD during the emergency braking phase is preliminarily discussed and validated through comparison with a volunteer test. The final forward out-of-position displacement of the BioRID II ATD falls within the range of volunteer
Fei, JingWang, PeifengQiu, HangLiu, YuShen, JiajieCheng, James ChihZhou, QingTan, Puyuan
In the pre-crash emergency braking scenario, the occupant inside the vehicle will move forward due to inertia, deviating from the standard upright seating position for which conventional restraint systems are designed. Previous studies have mainly focused on the influence of out-of-position (OOP) displacement on occupant injuries in frontal collisions, and provided solutions such as active pretensioning seatbelts (APS). But little attention has been paid to the influence of OOP on whiplash injury during a subsequent rear-end collision. To investigate the forward OOP impact on whiplash injuries and the effectiveness of APS in this accident scenario, a vehicle interior model with an active human body model (AHBM) was setup in the MADYMO simulation platform. Different braking strengths (0.8g and 1.1g), APS triggering times (from 0.2s before to 0.2s after the braking initiation) and pretensioning forces (from 100N to 600N) were input to the simulation matrix. The occupant’s forward OOP
Fei, JingQiu, HangWang, PeifengLiu, YuCheng, James ChihZhou, QingTan, Puyuan
The National Highway Traffic Safety Administration (NHTSA) published an Advance Notice of Proposed Rulemaking (ANPRM) to update the Federal Motor Vehicle Safety Standard (FMVSS) 207. Part of the ANPRM is to assess the merit of conducting quasi static body block seat pull tests and conducting FMVSS 301 rear crash tests at 80 km/h or higher with a 95th percentile ATD lap-shoulder belted in the front seats and limiting seatback deflection to 15 to 25 degrees. Prior to updating regulations, it is important to understand the seating design history and implications. This study was conducted to provide a historical background on seat design and performance using literature and test data. One objective was to first define the terminology used to describe occupant kinematics in rear crashes. Secondly, seat design evolution is then discussed. Third, test methods and test results were summarized, and fourth, the field performance are synopsized and discussed with respect to 2nd row occupant
Parenteau, ChantalBurnett, RogerDavidson, Russell
As the high-quality development of the new energy vehicle (NEV) and traction battery industries, the safety of traction batteries has become a global focus. Typically mounted at the bottom of NEVs, traction battery systems are particularly vulnerable to mechanical damage caused by bottom impacts, posing serious safety risks. This study investigates the damage sustained by NEV traction battery systems during bottom impact collisions, using computer tomography analysis to detail the damage mechanisms. The findings provide valuable data to enhance the safety and protective performance of traction batteries under such scenarios.
Yan, PengfeiWang, FangMa, TianyiHan, CeHe, Gaiyun
Over the last two decades many improvements have been made in stock car racing driver safety. One of these is the head surround, which is rigidly secured to and an integral part of the NASCAR (National Association for Stock Car Auto Racing, LLC) seating environment and serves as an effective restraint for head protection during lateral and rear impacts. However, previous head impact material specifications were optimized for moderate to severe impacts and did not address low severity impacts that occur frequently during typical driving, such as race restart vehicle nose-to-tail contact. This study focused on developing a test methodology for comprehensive evaluation of rear head surround materials for low, moderate and severe impacts. Specifically, this study aimed to formulate a specification that maintains previous material performance during high speed impacts, while decreasing head accelerations at low speed impacts. Quasi-static and dynamic drop tower testing of sample materials
Gray, Alexandra N.Harper, Matthew G.Mukherjee, SayakPatalak, John P.Gaewsky, James
In automotive engineering, seam welds are frequently used to join or connect various parts of structures, frames, cradles, chassis, suspension components, and body. These welds usually form the weaker material link for durability and impact loads, which are measured by lab-controlled durability and crash tests, as well as real-world vehicle longevity. Consequently, designing robust welded components while optimizing for material performance is often prioritized as engineering challenge. The position, dimensions, material, manufacturing variation, and defects all affect the weld quality, stiffness, durability, impact, and crash performance. In this paper, the authors present best practices based on studies over many years, a rapid approach for optimizing welds, especially seam welds, by adopting Design For Six Sigma (DFSS) IDDOV (Identify, Define, Develop, Optimization, and Verification) discrete optimization approach. We will present the case testimony to show the approach throughout
Qin, Wenxin (Daniel)
With the increasing adoption of Zero-Gravity Seats in intelligent cockpits, there is a growing concern over the safety of occupants in reclined postures during collisions. The newly released anthropomorphic test device (ATD), THOR-AV, has modified the neck, spine, and pelvis structures to better match reclined postures. This study aims to investigate the changes in kinematic response and injury metrics for occupants in reclined postures, through high-speed frontal sled tests utilizing the THOR-AV. The tests were conducted using an adjustable rigid seat with a zero-gravity characteristic and an integrated three-point seat belt. Six tests were performed across four seat configurations: Standard, Semi-Reclined, Reclined, and Zero-gravity postures. The input acceleration pulse for these tests was derived from the equivalent double trapezoidal waveform of the Mobile Progressive Deformable Barrier (MPDB) test. Data from sensors and high-speed video were collected for analysis. The results
Wang, QiangLiu, YuFei, JingYang, XiaotingWang, PeifengBai, Zhonghao
Utilization of fiber-reinforced composite laminates to their full potential requires consideration of angle-ply laminates in structural design. This category of laminates, in comparison with orthotropic laminates, imposes an additional degree of challenge, due to a lack of material principal axes, in determination of elastic laminate effective properties if the same has to be done experimentally. Consequentially, there is a strong inclination to resort to the usage of “CLPT” (Classical Laminated Plate Theory) for theoretically estimating the linear elastic mechanical properties including the cross-correlation coefficients coupling normal and shear effects. As an angle-ply laminate is architecturally comprised of layers of biased orthotropic laminas (based on unidirectional or woven bidirectional fibers), an essential prerequisite for the application of CLPT is an a-priori knowledge of elastic mechanical properties of a constituent lamina. It is natural to expect that the properties of
Tanaya, SushreeDeb, Anindya
Real-world data show that abdominal loading due to a poor pelvis-belt restraint interaction is one of the primary causes of injury in belted rear-seat occupants, highlighting the importance of being able to assess it in crash tests. This study analyzes the phenomenon of submarining using video, time histories, and statistical analysis of data from a Hybrid III 5th female dummy seated in the rear seat of passenger vehicles in moderate overlap frontal crash tests. This study also proposes different metrics that can be used for detecting submarining in full-scale crash tests. The results show that apart from the high-speed videos, when comparing time-series graphs of various metrics, using a combination of iliac and lap belt loads was the most reliable method for detecting submarining. Five metrics from the dynamic sensors (the maximum iliac moment, maximum iliac force drop in 1 ms, time for 80% drop from peak iliac force, maximum pelvis rotation, and lumbar shear force) were all
Jagtap, Sushant RJermakian, Jessica SEdwards, Marcy A
Sled crash tests are an important tool to develop automotive restraint systems. Compared with full-scale crash tests, the sled test has a shorter development cycle of the restraint system and lower cost. The objective of the present study is to create a cost-effective sled test methodology, calculate the optimal static yaw angle and loading curves, and analyze the motion response and injuries of the dummy in the small overlap crash test. The effectiveness of the proposed methodology was verified under two typical small overlap frontal crash modes: “energy-absorption” and “sideswipe”. The results show that with the calculated yaw angle α, the HIC was different from the small overlap crash model, but all remaining indices were within 5% of the injury criteria. All International Organization for Standardization (ISO) values between the combined accelerations of all parts of the dummy and those of the basic model exceeded 0.75, and some values were above 0.8. Therefore, the proposed sled
Yu, LiuChen, JianzhuoWan, Ming XinFan, TiqiangYang, PeilongNie, ZhenlongRen, LihaiCheng, James Chih
Pelvic pusher energy absorption pad in a vehicle saves the occupant from pelvic injuries in the event of a crash, especially side or pole crash. This pelvic pusher pad plays a crucial role in absorbing the impact energy from the body side and minimizing the impact to the occupant. Positioning of pelvic pusher pad with respect to occupant manikin position and torso angle, stiffening criteria for the energy absorption pad, maximum force and energy absorption target setting methodology and evaluation methods through CAE and part level physical validations are all discussed in detail. Pelvic pusher pad are of various types such as EPP moulded, blow moulded or injection moulded and the criteria differ for each type. For EPP moulded type, based on the EPP grade, S-S Graph gets converted to F-S Graph and validated accordingly. F-S Graph for a test vehicle is generated through sled test where the sled is made to impact the pelvis of ES2 Dummy at a constant velocity and the F-S Graph is
S M, Rahuld, AnanthaKakani, Phani KumarMalliboina, Mahendra
Peak upper and lower neck load data from rear impact crash testing were reviewed, aggregated, and analyzed from over 1,800 tests of existing peer-reviewed literature and research as well as available testing conducted by the Insurance Institute for Highway Safety (IIHS) and the National Highway Traffic Safety Administration (NHTSA). Both human volunteers and anthropomorphic test devices (ATDs) were subjects of the reviewed studies and testing. Peak upper and lower neck axial forces (compression and tension), sagittal shear forces, and sagittal moments (flexion and extension) from available crash testing were reported and analyzed as functions of measured change in velocity (delta-V) ranging from approximately 3 to 60 km/h (1.9 to 37 mph). This load data was then further analyzed for possible trends amongst various testing conditions, such as seat type, ATD used, and subject seating position within the vehicle chassis and seat to develop a simple linear model. The linear regressions
Kazmierczak, AlexUmale, SagarVisalli, AlyssaWebb, EllaKashdan, AryehRandles, BryanWelcher, Judson
A total of 148 tests were conducted to evaluate the Forward Collision Warning (FCW) and Automatic Emergency Braking (AEB) systems in five different Tesla Model 3 vehicles between model years 2018 and 2020 across four calendar years. These tests involved stationary vehicle targets, including a foam Stationary Vehicle Target (SVT), a Deformable Stationary Vehicle Target (DSVT), a live vehicle with brake lights, and a SoftCar360 designed for high-speed impact tests. The evaluations were conducted at speeds of 35, 50, 60, 65, 70, 75, and 80 miles per hour (mph) during both daytime and nighttime conditions and utilized early and medium FCW settings. These settings, part of Tesla's Collision Avoidance AssistTM, modify object detection alerts and the timing of visual and auditory warnings issued to drivers. The 2018 to 2020 vehicles initially utilized cameras, radar and ultrasonic sensors (USS) for object detection. Tesla updated their Autoilot software and detection algorithms to a vision
Harrington, ShawnNagarajan, Sundar Raman
In new energy vehicles, aluminum alloy has gained prominence for its ability to achieve superior lightweight properties. During the automotive design phase, accurately predicting and simulating structural performance can effectively reduce costs and enhance efficiency. Nevertheless, the acquisition of accurate material parameters for precise predictive simulations presents a substantial challenge. The Johnson-Cook model is widely utilized in the automotive industry for impact and molding applications due to its simplicity and effectiveness. However, variations in material composition, processing techniques, and manufacturing methods of aluminum alloy can lead to differences in material properties. Additionally, components are constantly subjected to complex stress states during actual service. Conventional parameter calibration methods primarily rely on quasi-static and dynamic tensile tests, offering limited scope in addressing compression scenarios. This paper proposes an inversion
Kong, DeyuGao, Yunkai
The rapid growth of electric vehicles (EVs) has led to a significant increase in vehicle mass due to the integration of large and heavy battery systems. This increase in mass has raised concerns about collision energy and the associated risks, particularly in high-speed impacts. As a consequence, crashworthiness evaluations, especially front-impact regulations, have become increasingly stringent. Crash speed between the vehicle and the Mobile Progressive Deformable Barrier (MPDB) is increasing, reflecting the growing emphasis on safety in the automotive industry. Moreover, a new frontal pole crash scenario is under consideration for future regulatory standards, highlighting the continuous evolution of crash testing protocols. To ensure occupant protection and battery safety, manufacturers have traditionally used Hot Blow Forming technology for producing closed-loop dash lower cross member components. However, this process is both costly and energy-intensive, necessitating more
Lee, JongminKim, DonghyunJang, MinhoKim, GeunhoSeongho, YooKim, Kyu-Rae
The development of autonomous driving technology will liberate the space in the car and bring more possibilities of comfortable and diverse sitting postures to passengers, but the collision safety problem cannot be ignored. The aim of this study is to investigate the changes of injury pattern and loading mechanism of occupants under various reclined postures. A highly rotatable rigid seat and an integrated three-point seat belt were used, with a 23g, 50kph input pulse. Firstly, the sled test and simulation using THOR-AV in a reclined posture were conducted, and the sled model was verified effective. Based on the sled model, the latest human body model, THUMS v7, was used for collision simulation. By changing the angle of seatback and seat pan, 5 seat configurations were designed. Through the calculation of the volunteers' pose regression function, the initial position of THUMS body parts in different seat configurations was determined. The responses of human body parts were output
Yang, XiaotingWang, QiangLiu, YuFei, JingWang, PeifengLi, ZhenBai, Zhonghao
Research on modeling head injury metrics and head acceleration waveforms from real-world collisions has been limited compared to vehicle crash pulses. Prior studies have used rectangular, triangular, polynomial, half-sine, and haversine pulse functions to model vehicle crash pulses and have employed more complex approximations for head injury metrics. This study aimed to develop a method to predict 15 ms Head Injury Criterion (HIC15) in frontal passenger vehicle impacts using these simple pulse functions, where only occupant peak head acceleration and head impact duration are known. Vehicle crash tests from the New Car Assessment Program (NCAP) were selected for frontal impacts that included driver occupants. Head acceleration and shoulder belt load channels of Hybrid III 50th percentile male anthropomorphic test devices were collected and separated for training a set of ratios and testing their performance. Rectangular, triangular, quadratic, half-sine, and haversine pulse functions
Westrom, ClydeTanczos, RachelAdanty, KevinShimada, Sean
The National Highway Safety Administration (NHTSA) recently published an Advanced Notice of Proposed Rulemaking (ANPRM) to evaluate seat performance in rear impacts [1]. The ANPRM was issued partially in response to two petitions requesting an increase in seatback strength requirements and high-speed testing with various size Anthropometric Test Devices (ATDs). To better understand the effect of these requests, this study evaluates ATD responses with two high-speed rear sled conditions, three occupant sizes and various seat designs. Seat designs varied from modern conventional seats with yielding properties to stronger and stiffer seats represented by seat integrated restraint (SIR) designs, and rigidized SIR seats. Twenty-four rear sled tests were analyzed. The tests were matched by crash severity, seat designs (strength), ATD sizes and initial postures (nominal/in-position, leaned forward and leaned outboard). The test data and videos were reviewed to identify time coinciding with
Parenteau, ChantalBurnett, Roger
There are numerous commercially available neck and back support/cushion/pillow devices which are commonly attached to seats by vehicle owners. To our knowledge, there has been no published research on the biomechanical effects of these devices in low-speed rear impacts. To address this, a series of 54 simulated low-speed rear impact tests were conducted using a validated remote-controlled crash sled system. All tests utilized an instrumented BioRID II rear impact anthropomorphic test device (ATD) restrained using a 3-point seatbelt system in a 2018 Toyota Camry LE driver’s seat. Two delta-V ranges were used: a lower range from 7.2 to 8.0 kph (4.5 to 5.0 mph) and a higher range from 10.5 to 11.3 kph (6.5 to 7.0 mph). Six neck only devices, one combination neck and back device, and three back only devices were assessed. Two tests per delta-V range for each device and each device adjustment position were conducted and compared against five reference tests without any devices at each delta
Phan, AndrewGross, JamieUmale, SagarCrowley, ShannonGlasser, GabrielFurbish, Christopher
Impact resistance is crucial for assessing charging pile safety and reliability. This study proposes a prediction model, called GA-BP neural network, which achieved prediction errors below 5% and reduced computation time by over 95% in comparison to finite element analysis (FEA). Initially, the charging pile impact test platform is constructed, and a matching finite element simulation model is developed. The correctness of the simulation model is then verified by integrating the experimental findings. Furthermore, the Latin hypercube approach is used to create 200 sets of simulation schemes, and using the Python programming language, the impact resistance performance indicators of charging piles are automatically collected. Next, a genetic algorithm is used to optimize the initial weight and bias of the BP neural network, lastly, fine-tune the hyperparameters in the neural network to develop a prediction model for the impact resistance performance of the charging pile. The GA-BP model
Jiang, BingyunHu, PengLiu, ZhenyuYuan, PengfeiLiu, Hui
The purpose of this study was to investigate the use of quasistatic force deformation (QSFD) data to represent the collision forces in low-speed collinear collisions when there is damage to vehicle body structures as well as the bumpers. In this study five full-scale underride/override crash tests were performed and simulated with QSFD data. In each crash test a bumper or a trailer underride guard on a bullet vehicle overrode the rear or front bumper of a target vehicle and damaged structures above the bumper of the target vehicle. A QSFD measurement was performed substantially similar to the vehicle interactions in the crash using a complete exemplar target vehicle that was rigidly attached to the earth. The output of a QSFD measurement is force deflection data for the vehicle pair. Each crash test was simulated using the QSFD data, the weights of the test vehicles, the closing speed of the test vehicles, and the restitution measured in the crash test. The output of a simulation was
Gall, JessicaScott, William R.Bonugli, EnriqueWatson, Richard A.Fischer, Patrick
The usage of Electric Vehicles (EVs) and the annual production rate have increased significantly over the years. This is due to the development of rechargeable electrical energy storage system (battery pack), which is the main power source for EVs. Lithium-ion batteries (LIBs) pack is predominantly used across all major vehicle categories such as 2-wheelers, 3-wheelers and light commercial vehicle. LIB is one of the high energy-dense sources of volume. However, LIBs have a challenge to pose a risk of short circuits and battery pack explosions, when exposed to damage scenarios. In the present study, the controlled crash analysis is performed for various velocities ranging from 50 kmph to 72 kmph against an obstruction directly and at an offset from the wheel, so as to mimic the real-world crash of high-speed two-wheelers. The behavior of the battery enclosure is examined through evaluating the structural integrity of the battery enclosure used in a realistic two-wheeler after crash at
Venkatesan Sr, AiyappanNelson, N RinoHariharan Nair, Adarsh
As the adoption of new energy vehicles expands globally, the safety performance of their traction batteries has garnered significant attention due to the potential hazards posed by road debris and collisions. These safety concerns have become a major impediment to the advancement of these vehicles. This paper aims to analyze the impact resilience of traction batteries under frontal collision scenarios to evaluate their safety under specific conditions. A multi-level evaluation model for traction batteries is developed and integrated with computer tomography system analysis to investigate the extent of damage sustained by the battery system during frontal impacts. Utilizing a structured battery system damage assessment method, the study provides a quantitative analysis of the damage severity resulting from collisions. This offers both theoretical insights and practical guidance for the testing and evaluation of traction batteries.
Yan, PengfeiWang, FangMa, TianyiHan, CeHe, Gaiyun
The present research explores the potential of high-performance thermoplastics, Polymethyl Methacrylate and Polyurethane, to enhance the passive safety of automotive instrument panels. The purpose is to evaluate and compare the passive safety of these two materials through the conduct of the Charpy Impact Test, Tensile Strength Test, and Crush Test —. For this, five samples were prepared in the case of each material via injection moulding, which enabled reliability, and consistency of the findings. As a result, it was found that in the case of the Charpy Impact Test, the average impact resistance varies with PMMA exhibiting a level of 15.08 kJ/m2 as opposed to the value of 12.16 kJ/m2 for PU. The Tensile Strength Test produced the average tensile strength of 50.16 for PMMA and 48.2 for PU, which implied superior structural integrity under tension for the first type of thermoplastic. Finally, the Crush Test showed that PMMA is more resistant to crushes on average than PU with the
Natrayan, L.Kaliappan, SeeniappanMothilal, T.Balaji, N.Maranan, RamyaRavi, D.
In the automotive industry, a good vehicle is one that not only provides comfort and adequate on-road performance but also ensures safety for its users. Therefore, various standards have been created to qualify and ensure that cars meet minimum requirements. Assays include frontal and side impact tests. However, physical tests end up being costly if performed frequently, and thus, increasing the correlation between these and computational simulations has been explored in recent years. Within the computational scope, given the nonlinear nature of the functions involved in such studies, the use of metaheuristics (MH) with constraint handling techniques (CHT) has been employed to obtain better results for such scenarios. In this work, three MH algorithms are used: Archimedean Optimization (AOA), Sine-Cosine Algorithm (SCA), and Dung Beetle Optimization (DBO). They are coupled with CHTs of the penalty methods (PM) type in their most basic character, such as Static Penalty Method (SPM
Souza Silva, PauloDezan, Daniel JonasFerreira, Wallace Gusmão
The behavior of mechanical structures subjected to impacts is a topic of great relevance, with one of its applications being in the context of collisions on urban roads. According to data obtained from the electric bus monitoring platform E-Bus Radar, the fleet of vehicles with this means of propulsion has grown significantly in the last 6 years. Just from 2022 to 2023, the growth was 51%, jumping from 2669 to 4020 registered vehicles in Latin America. In this context, the present study investigated the behavior of the rear structure of an electric bus - EB in a rear-end collision scenario. The study of this region was motivated by the fact that it houses 4 out of the 12 battery packs and other electrical components. The main objective of this work is to evaluate the efficiency of the anti-intrusion and impact absorption mechanism to ensure the integrity of the batteries. Since damage in a collision can release different types of flammable electrolytes and even trigger a fire, posing a
Menino, Bruno G.Sordi, AlexsandroBraida, Claudio A. B.Biondo, FelipeSpengler, FelipeMagnabosco, Guilherme
Safety concerns surrounding new energy vehicles have gained increasing national and social attention. Bottom impacts to power batteries are a leading cause of fires and explosions in new energy vehicles. Focusing on the safety of power battery bottom impacts, this article first proposes applying honeycomb panels to the battery’s bottom guard plate. Through the ball impact test, the effect of honeycomb panel surface material thickness on bottom protection is studied, and the mechanism of the honeycomb panel’s ball impact protection is explored. Second, the honeycomb panel and the aluminum alloy plate are structurally compounded to improve the ball impact protection ability. Finally, the optimized composite bottom guard plate is assembled on the lower box of the power battery, and the whole package ball impact experiment is successfully verified. This study serves as a reference for future research on power battery bottom impact protection and the industrial application of bottom guard
Hongguang, HuangYong, ZengWeiquan, Zeng
Vehicles equipped with automated driving systems (ADS) may have non-traditional seating configurations, such as rear-facing for front-row occupants. The objectives of this study are (1) to generate biomechanical corridors from kinematic data obtained from postmortem human subjects (PMHS) sled tests and (2) to assess the biofidelity of the Global Human Body Models Consortium (GHBMC) 50th male (M50-O) v6.0 seated in an upright (25-deg recline) Honda Accord seat with a fixed D-ring (FDR) in a 56 km/h rear-facing frontal impact. A phase optimization technique was applied to mass-normalized PMHS data for generating corridors. After replicating the experimental boundary conditions in the computational finite element (FE) environment, the performance of the rigidized FE seat model obtained was validated using LSTC Hybrid III FE model simulations and comparison with experiments. The most recent National Highway Traffic Safety Administration (NHTSA) Biofidelity Ranking System (BRS) method was
Pradhan, VikramRamachandra, RakshitStammen, JasonKracht, CoreyMoorhouse, KevinBolte, John H.Kang, Yun-Seok
There is evidence to suggest that males and females respond differently in motor vehicle collisions, making it important to study how both sexes respond to vehicle safety systems. The THOR 5th-percentile female (THOR-05F) anthropomorphic test device (ATD) was developed to represent a small female occupant better than the Hybrid III 5th-percentile female (HIII-05F) ATD. However, there are few studies in which they have been directly compared. Therefore, the objective of this study was to compare the responses of the two ATDs in matched frontal sled tests simulating a realistic driver seat environment. A 7th-generation Toyota Camry driver seat test buck was used with Camry parts (i.e., 3-point belt, modified seat, steering wheel, airbag, and column). The belt was equipped with a 4-kN load limiter and pretensioner. Rigid foam (65 psi) was used to represent the knee bolster. Thirteen tests were conducted using speeds of 30 and 56 kph. Chest bands were used to measure external chest
Boyle, David M.Albert, Devon L.Hardy, Warren N.Kemper, Andrew R.
Head injuries from interior impacts during vehicle accidents are a significant cause of fatalities in India. Data from the National Crime Records Bureau (NCRB) for 2023 reveals that approximately 15% of the total 150,000 road fatalities were due to head impacts on vehicle interiors, resulting in about 22,500 deaths. Thus, head impact protection in a car crash is key during the design of vehicle interiors. IS 15223 and ECE-R21 provide specific guidelines for head impact testing of instrument panels and consoles in vehicles to ensure compliance with safety standards and minimize the risk of head injury during collisions. By systematically addressing each aspect of IS 15223 and ECE- R21 in the design, testing, and documentation phases, manufacturers can ensure that console armrests are optimized for safety. This approach not only helps meet regulatory standards but also enhances overall occupant protection in vehicles during collisions. The objective of this paper is to design a console
Malhotra, DeepakVaishnav, SureshSureshkumar Presannakumari, RajasilpiMangal, GautamKeshri, Amit
In the realm of commercial vehicle design, enhancing the durability of bumpers and headlamps is paramount for ensuring safety and reducing maintenance costs. This study explores the development of a lightweight bumper design with optimized resonance frequency to improve the durability of these critical components. The research focuses on innovative design techniques to achieve a balance between weight reduction and structural integrity. The primary objective is to minimize the impact forces transmitted to the bumper and headlamp assemblies during vibrations. By employing finite element analysis (FEA) and experimental validation, the study identifies the optimal resonance frequency that mitigates the risk of resonance-induced damage. Additionally, the study examines the influence of geometric modifications on the bumper’s performance. Various design iterations are analyzed to determine the most effective configuration for enhancing durability while maintaining compliance with industry
Pandey, SudheerGanesan, Balaji
The structural integrity of the steering wheel is important for vehicle operations. It is subjected to various load conditions during the vehicle motion. It thus becomes important to understand various aspects of the same which include stiffness, natural frequency, and regulatory requirements i.e. body block test, head form impact test, etc. Simulation plays an important role in understanding the structural integrity and validation requirements of products at the design stage itself. This paper discusses the modeling and simulation of the steering wheel at both the armature level and the complete steering wheel level. As armature is critical from a structural strength and stiffness point of view, certain simulations like modal analysis are performed first at the armature level, and design iterations were done to achieve the natural frequency target. The list of simulations performed includes modal analysis, bending rigidity, static compression, bending stiffness, body block test and
Rathore, Gopal SinghKumar, AnkitChauhan, Adesh KumarDas, A.P.Sahu, Hemanta Kumar
In order to compare test results obtained from different crash test facilities, standardized coordinate systems need to be defined for crash test dummies, vehicle structures, and laboratory fixtures. In addition, recorded polarities for various transducer outputs need to be defined relative to positive directions of the appropriate coordinate systems. This SAE Information Report describes the standardized sign convention and recorded output polarities for various transducers used in crash testing.
Safety Test Instrumentation Standards Committee
With the capability of predicting detailed injury of occupants, the Human Body Model (HBM) was used to identify potential injuries for occupants in car impact events. However, there are few publications on using HBM in the aviation industry. This study aims to investigate and compare the head, neck, lumbar spine and thoracic responses of the Hybrid III and the THUMS (Total Human Model for Safety) model in the horizontal 26g and vertical 19g sled tests required by the General Aviation Aircraft Airworthiness Regulations. The HIC of THUMS and Hybrid III did not exceed the requirements of airworthiness regulations. Still, THUMS had higher intracranial pressures and intracranial stresses, which could result in brain injury to the occupants. In vertical impact, the highest stress of the neck of THUMS appears at the cervical spine C2 and the upper neck is easily injured; in horizontal impact, the cervical spine C7 has the highest load, and the lower neck is easily injured. Due to the low
Shi, XiaopengDing, XiangheGuo, KaiLiu, TianfuXie, Jiang
Ongoing research in simulated vehicle crash environments utilizes postmortem human subjects (PMHS) as the closest approximation to live human response. Lumbar spine injuries are common in vehicle crashes, necessitating accurate assessment methods of lumbar loads. This study evaluates the effectiveness of lumbar intervertebral disc (IVD) pressure sensors in detecting various loading conditions on component PMHS lumbar spines, aiming to develop a reliable insertion method and assess sensor performance under different loading scenarios. The pressure sensor insertion method development involved selecting a suitable sensor, using a customized needle-insertion technique, and precisely placing sensors into the center of lumbar IVDs. Computed tomography (CT) scans were utilized to determine insertion depth and location, ensuring minimal tissue disruption during sensor insertion. Tests were conducted on PMHS lumbar spines using a robotic test system for controlled loading in flexion
Burns, Michael R.Caldwell, A. JamesShin, JeesooSochor, Sara H.Kopp, Kevin P.Shaw, GregGepner, BronislawKerrigan, Jason R.
Seventeen research posters were prepared and presented by student authors. The posters covered a wide breadth of works-in-progress and recently completed projects. Topics included a variety of body regions and injury scenarios: Biofidelity Corridors of Powered Two-Wheeler Rider Kinematics from Full-Scale Crash Testing Using Postmortem Human Subjects, Meringolo et al. Cervical Vertebral and Spinal Cord Injuries Remain Overrepresented in Rollover Occupants, Al-Salehi et al. The Effect of Surfaces on Knee Biomechanics during a 90-Degree Cut, Rhodes et al. Investigating the Variabilities in the Spinal Cord Injury in Pig Models Using Benchtop Test Model and Ultrasound Analyses, Borjali et al. Relationship between Tackle Form and Head Kinematics in Youth Football, Holcomb et al. Comparing Motor Vehicle Collision Injury Incidence between Pregnant and Nonpregnant Individuals: A Case–Control Study, Levine et al. Development of an Automated Pipeline to Characterize Full Rib Cage Shape
Bautsch, Brian T.Cripton, Peter A.Cronin, Duane
Fragility fracture of the hip is a global health concern with generally poor outcomes. Clinical studies have shown prophylactic augmentation of the femur to be a plausible intervention with success in some approaches; however, its use is not yet widespread in the clinical community. We aimed to evaluate the efficacy and clinical safety of prophylactic intramedullary nailing for hip fracture prevention after a fall impact in six cadaveric pelvis–femurs. Post-fall fracture status of the native specimens was determined in a virtual control group built using a validated and peer-reviewed finite element method. A commercially available intramedullary nailing system was prophylactically implanted in all specimens. After augmentation, specimens were subjected to an experimental sideways fall impact and inspected for fracture. Overall, fracture status was unchanged or lowered in severity in the augmented group compared to the native control group. No sign of femur fracture was found in the
Bliven, Emily K.Fung, AnitaBaker, AlexanderHelgason, BenediktGuy, PierreCripton, Peter A.
Exploring the mechanical properties of soft tissues under compressive loading is crucial for understanding their role in automobile incidents. Soft tissues, which serve as cushions or padding between bone and vehicle interiors, significantly influence contact duration and forces, thereby altering incident kinematics and injury. In this investigation, muscle and soft connective tissues from post-mortem human subjects (PMHS) forearms were excised and subjected to compression and indentation testing methods at various rates and strains. Specific samples with higher proportions of muscle were compared against samples without muscle tissues to evaluate the role of compositional changes. Anthropomorphic test device (ATD) upper extremity foam and vinyl–foam composite analog tissues underwent similar testing for comparison. High impact rates simulating those in high-speed automotive collisions were achieved using a custom-built drop tower impactor setup. The results revealed significantly
Dennis, Cole J.Quenneville, Cheryl E.
This SAE Recommended Practice describes the test procedures for conducting free-motion headform testing of heavy truck cab interior surfaces and components. A description of the test setup, instrumentation, impact configuration, target locations, and data reduction is included.
Truck Crashworthiness Committee
The increased use of computational human models in evaluation of safety systems demands greater attention to selected methods in coupling the model to its seated environment. This study assessed the THUMS v4.0.1 in an upright driver posture and a reclined occupant posture. Each posture was gravity settled into an NCAC vehicle model to assess model quality and HBM to seat coupling. HBM to seat contact friction and seat stiffness were varied across a range of potential inputs to evaluate over a range of potential inputs. Gravity settling was also performed with and without constraints on the pelvis to move towards the target H-Point. These combinations resulted in 18 simulations per posture, run for 800 ms. In addition, 5 crash pulse simulations (51.5 km/h delta V) were run to assess the effect of settling time on driver kinematics. HBM mesh quality and HBM to seat coupling metrics were compared at kinetically identical time points during the simulation to an end state where kinetic
Wade von Kleeck, B.Caffrey, JulietteWeaver, Ashley A.Gayzik, F. ScottHallman, Jason
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.
New tests for a Truck Safe rating scheme aim to emulate real-world collisions and encourage OEMs to fit collision avoidance technologies and improve driver vision. Euro NCAP has revealed the elements it is considering as part of an upcoming Truck Safe rating, and how it intends to test and benchmark truck performance. The announcement was made to an audience of international road safety experts at the NCAP24 World Congress in Munich, Germany, in April. The action is intended to mitigate heavy trucks' impact on road safety. The organization cited data showing that trucks are involved in almost 15% of all EU road fatalities but represent only 3% of vehicles on Europe's roads. Euro NCAP says the future rating scheme is designed to go further and faster than current EU truck safety regulations. The organization's goal is to drive innovation and hasten the adoption of advanced driver-assistance systems (ADAS) such as automatic emergency braking (AEB) and lane support systems (LSS), while
Gehm, Ryan
This document provides background information, rationale, and data (both physical testing and computer simulations) used in defining the component test methods and similarity criteria described in SAE Aerospace Recommended Practice (ARP) 6330. ARP6330 defines multiple test methods used to assess the effect of seat back mounted IFE monitor changes on blunt trauma to the head and post-impact sharp edge generation. The data generated is based on seat and IFE components installed on type A-T (transport airplane) certified aircraft. While not within the scope of ARP6330, generated test data for the possible future development of surrogate target evaluation methods is also included.
Aircraft Seat Committee
Frontal-crash sled tests were conducted to assess submarining protection and abdominal injury risk for midsized male occupants in the rear seat of modern vehicles. Twelve sled tests were conducted in four rear-seat vehicle-bucks with twelve post-mortem human surrogates (PMHS). Select kinematic responses and submarining incidence were compared to previously observed performance of the Hybrid III 50th-percentile male and THOR-50M ATDs (Anthropomorphic Test Devices) in matched sled tests conducted as part of a previous study. Abdominal pressure was measured in the PMHS near each ASIS (Anterior Superior Iliac Spine), in the inferior vena cava, and in the abdominal aorta. Damage to the abdomen, pelvis, and lumbar spine of the PMHS was also identified. In total, five PMHS underwent submarining. Four PMHS, none of which submarined, sustained pelvis fractures and represented the heaviest of the PMHS tested. Submarining of the PMHS occurred in two out of four vehicles. In the matched tests, the
Guettler, Allison J.Bianco, Samuel T.Albert, Devon L.Boyle, David M.Kemper, Andrew R.Hardy, Warren N.
THOR-AV 5F, a modified THOR-5F dummy, was designed to represent both upright and reclined occupants in vehicle crashworthiness studies. The dummy was evaluated in four test conditions: a) 25° seatback, 15 km/h, b) 25° seatback, 32 km/h, c) 45° seatback, 15 km/h, d) 45° seatback, 32 km/h. The dummy’s biomechanical responses were compared against those of postmortem human subjects (PMHS) tested in the same test conditions. The latest National Highway Traffic Safety Administration (NHTSA) BioRank method was used to provide a biofidelity ranking score (BRS) for each data channel in the tests to assess the dummy’s biofidelity objectively. The evaluation was categorized into two groups: restraint system and dummy. In the four test conditions, the restraint system showed good biofidelity with BRS scores of 1.49, 1.47, 1.15, and 1.79, respectively. The THOR-AV 5F demonstrated excellent biofidelity in three test conditions: 25° seatback, 15 km/h (BRS = 0.76); 25° seatback, 32 km/h (BRS = 0.89
Wang, Z. JerryHumm, JohnHauschild, Hans W.
With the current trend of including the evaluation of the risk of brain injuries in vehicle crashes due to rotational kinematics of the head, two injury criteria have been introduced since 2013 – BrIC and DAMAGE. BrIC was developed by NHTSA in 2013 and was suggested for inclusion in the US NCAP for frontal and side crashes. DAMAGE has been developed by UVa under the sponsorship of JAMA and JARI and has been accepted tentatively by the EuroNCAP. Although BrIC in US crash testing is known and reported, DAMAGE in tests of the US fleet is relatively unknown. The current paper will report on DAMAGE in NCAP-like tests and potential future frontal crash tests involving substantial rotation about the three axes of occupant heads. Distribution of DAMAGE of three-point belted occupants without airbags will also be discussed. Prediction of brain injury risks from the tests have been compared to the risks in the real world. Although DAMAGE correlates well with MPS in the human brain model across
Prasad, PriyaBarbat, Saeed D.Kalra, AnilDalmotas, Dainius J.
In this paper, experimental studies were conducted to examine the mechanical behavior of a polymer composite material called polyamide with glass fiber (PA6-GF), which was fabricated using the three-dimensional (3D) fusion deposition modeling (FDM) technique. FDM is one of the most well-liked low-cost 3D printing techniques for facilitating the adhesion and hot melting of thermoplastic materials. PA6 exhibits an exceptionally significant overall performance in the families of engineering thermoplastic polymer materials. By using twin-screw extrusion, a PA6-GF mixed particles made of PA6 and 20% glass fiber was produced as filament. Based on literature review, the samples have been fabricated for tensile, hardness, and flexural with different layer thickness of 0.08 mm, 0.16 mm, and 0.24 mm, respectively. The composite PA6-GF behavior is characterized through an experimental test employing a variety of test samples made in the x and z axes. The mechanical and physical characteristics of
Sivanesh, A. R.Soundararajan, R.Natrayan, M.Nallasivam, J. D.Santhosh, R.
A and B stiffness coefficients to model the frontal stiffness of vehicles is a commonly used and accepted technique within the field of collision reconstruction. Methods for calculating stiffness coefficients rely upon examining the residual crush of a vehicle involved in a crash test. When vehicles are involved in a collision, portions of the crushed vehicle structures rebound from their maximum dynamic crush position. Once the vehicle structures have finished rebounding, the remaining damage is called the residual crush. A problem can arise when the plastic bumper cover rebounds more than the vehicle's structural components, resulting in an air gap between the structural components and the plastic bumper cover. Most modern New Car Assessment Program (NCAP) tests quantify crush in the test reports based on the deformed location of the plastic bumper cover and not the structural components behind the plastic bumper cover. This results in an underreporting of the actual residual crush
Neal, JosephLipscomb, MatthewFunk, Charles
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. LS
Challa, Balaji Naga Sai AbhishiktYang, PeiyuCarlson, MichaelSuntay, BrianStammen, JasonNoll, Scott
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