Browse Topic: Impact tests

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IAQG-03282025-1 IAQG-03282025-1 (Current)04/02/2025
IAQG-03282025-1
IAQG-1 Standards Committee
Novel Method for Vehicle Crash Pulse prediction2024-26-000201/16/2024
Airbags are crucial elements of passive safety in vehicles that help minimizing occupant injuries during various crash scenarios such as frontal, side, and oblique impacts. Airbags in cars are now mandatory in many countries, and their performance depends on how well the system is designed. A well-tuned airbag deployment algorithm is necessary to score superior NCAP safety ratings. Tuning of airbag deployment algorithms requires several data points which are obtained through actual crash testing. This is a cumbersome and expensive process as it involves crash tests for each scenario (e.g., full front barrier, offset deformable barrier, angled impact, etc.) at multiple test speeds. These tests are destructive and render the vehicles only worthy of scrap. The data gathered from various sensors (acceleration, pressure, etc.) is used to develop robust vehicle model specific algorithms that must correctly identify the crash scenario and send airbag firing signal at the optimal pre-decided
Kumar, Ayush
Seatback Failures and Human Tolerance in Severe Rear Impacts2024-26-000301/16/2024
Seatback and head restraints is the primary restraining device 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
Child Injury Pattern and Mechanism Differences Based on the Front Seat Occupancy Status in Rear Impacts with Severe Structural Intrusions from the Rear2024-26-000501/16/2024
Child crash injury protection in severe rear impact chiefly depends on how well the rear survival space bounded by the vehicle structure is maintained. Previous research and studies have shown the ill effects of front seatback collapse intruding into the rear child survival space from the front with minor or no intrusions from the rear. This paper shows the child injury pattern and fatal injury mechanism for a rear impact crash with a severe compartment intrusion from the rear without any front seat occupant. Furthermore, it compares the injury outcome with a similar crash and severe intrusion in the presence of the front occupant employing a full-scale vehicle-to-vehicle crash test. A detailed real-world crash investigation is conducted to identify the injury mechanism. It is compared with the outcome of similar severity rear impact vehicle-to-vehicle crash tests producing different injury patterns. The comparison and the analysis show that the survival space intrusion due to safety
Thorbole, Chandrashekhar
Importance of Pole Side Impact Test for Assessment of Curtain Airbags2024-26-001901/16/2024
Government of India, in 2017, mandated a Side Impact Test (AIS 099 technically aligned to UN ECE Regulation No. 95.03 series of amendments) on M1 category Passenger Vehicles to ensure protection of occupants in lateral impact accident scenarios. Later, in 2022, a draft notification has been issued by the Government mandating installation of 6 airbags (2 No.of thorax side airbags, 2 No. of head protection or curtain airbags in addition to already mandated installation of Driver and Passenger Airbags) in all such passenger vehicles. However, the vehicles fitted with side thorax airbag and curtain airbags are proposed to be assessed as per AIS099 test only. Curtain Airbags are typically installed to protect occupant’s head from severe injuries in narrow object impacts simulated in Pole Side Impact Test Configurations. However, at present, India has not notified an equivalent standard to UN R135 demanding performance of the vehicle in pole side impact scenarios. Typically, OEMs may need to
Jaju, Divyan, Kulkarni, Dileep, Mahindrakar, Rahul, Mahajan, Rahul
Crash Performance Improvement: The Impact of Engine Mount Crash Plates on Achieving a 5-Star Safety Rating2025-01-008505/05/2023
Electric vehicles (EVs) differ from internal combustion engine (ICE) vehicles in that they lack a conventional engine and feature an electric drive unit, leading to distinct dynamic behaviours in the powertrain. Additionally, the arrangement of auxiliary components in EVs often differs from that in traditional ICE vehicles, which can sometimes significantly impact safety ratings. This paper examines a case study of a critical failure during a crash test, where displacement of an engine mount arm caused substantial structural intrusion and reduced the vehicle's safety rating. To address this issue and enhance crashworthiness, a "crash plate" was designed and integrated into the mount system. This solution effectively constrained the mount arm's movement during impact, preventing the intrusion observed in previous tests. The paper provides a detailed analysis of the crash plate's dimensions and its relationship to the engine mount, demonstrating its potential for broader application in
Hazra, Sandip, Khan, Arkadip, Mohare, Gourishkumar
PERFORMANCE OF FIVE-POINT SEAT BELT ON OCCUPANT SAFETY IN VEHICLE ON FRONTAL CRASH TEST2022-28-049311/18/2022
In day-to-day life, accidents do occur frequently all-round the globe. It is difficult to prevent these accidents as they occur due to different reasons, which cannot be easily controlled. But the fatal injuries occurring to passengers can be reduced by installing safety systems in vehicles, which will help in saving the life of mankind. There are many safety systems being installed in vehicles such as seat belt restraints, air bags etc. Generally, three-point seat belts are installed in passenger vehicles for safety purposes. This type of seat belt doesn't arrest the entire motion of the occupant body during vehicle crashes, which can lead to fatal injuries and sometimes even death during vehicle crashes. In order to buckle passengers with seats, we can use five-point seat belts which will help in mitigating the injuries as compared to three-point seat belts. In this paper, we evaluate the performance of five-point seat belts on occupant safety during vehicle crash on flat rigid
Jeyakumar, P, CHANDRAN, DINESHKUMAR
Rear-End Impacts – Part 2: Sled Pulse Effect on Front-Seat Occupant Responses 2022-01-103903/29/2022
This study was conducted to assess the effects of differing rear impact pulse characteristics on restraint performance, front-seat occupant kinematics, biomechanical responses, and seat yielding. Five rear sled tests were conducted at 40 km/h using a modern seat. The sled buck was representative of a mid-sized driver environment in a generic sport utility vehicle. The peak acceleration, acceleration shape and duration were varied. Three of the pulses were selected based on published information and two were calculated to assess the effects of long and short initial acceleration rate using a trapezoidal characteristic shape. The angle at maximum seatback rearward deformation varied from 26 to 47 degrees. It was lowest in Pulse 1 which simulates an 80 km/h car-to-car rear impact. The seatback plastic deformation was greater in the pulse with a long initial acceleration rate, Pulse 4, than in the short acceleration rate, Pulse 5 (28 degrees v 22 degrees). Coincidingly, the longitudinal
Parenteau, Chantal, White, Samuel, Burnett, Roger
A Comparison of THOR 50M Anthropomorphic Test Devices in Frontal Sled Tests when equipped with and without On-Board Data Acquisition Systems. 2022-01-104803/29/2022
This paper summarizes a series of matched-pair frontal sled tests using the THOR 50th Percentile Male anthropomorphic test device (ATD). Testing was conducted to compare the response of an ATD equipped with an on-board data acquisition system (DAS) to that of one equipped with an off-board system. Sled testing was performed using a modified version of NHTSA’s Gold-Standard test method consisting of a generic buck with a ridged seat and a 3-point seatbelt system. Eight tests were conducted, all using a common generic 30 km/h crash pulse with a peak deceleration of 9 G’s, and a 2.5 kN load limiting 3-point seatbelt retractors without pretensioners. Four tests were conducted with each ATD, two tests with a left shoulder belt routing and two with a right shoulder belt routing to allow for evaluation of the ATD repeatability under each belt routing. Attention was given to the potential for a heating effect of the on-board DAS to influence the dummy response; particularly the chest
Ward, Josh, Dellicolli, Anthony, Dix, Jeff
Stiffness Coefficients of Heavy Trailer Rear Structures2022-01-099503/29/2022
Post-crash deformation is often relied upon to determine impact severity, force of impact and the resultant change in velocity of the impact phase. Understanding how the vehicle’s structure absorbs crash energy allows a reconstructionist to utilize the post-crash deformation in these calculations. For light-duty passenger vehicles, there are many publicly available crash test databases that allow for vehicle specific and vehicle class specific energy absorption characteristics to be analyzed. Traditionally, commercial vehicles are not part of the publicly available crash test databases. The Insurance Institute for Highway Safety (IIHS) conducted a series of tests with many different box trailers and seventh generation Chevrolet Malibu’s (2008 through 2012 model years). The box trailers were from different manufacturers (Wabash, Greatdane, Utility, Vanguard, Hyundai, Manac, Stoughton, and Struck) and different model years (2011-2018). The tests consisted of stationary box trailers
Suway, Jeffrey, Desai, Elvis, Cornetto, Anthony
A Bayesian method for load identification of powertrain mounting system with interval uncertainty2022-01-074603/29/2022
It is very important to accurately identify the load of the vehicle in the working state for the study of vehicle vibration and noise. At present, the identification technology of dynamic load mainly focuses on the deterministic model, but there are always structural model errors in practical engineering. Bayesian method and interval theory can deal with unknown-but-bounded uncertainties in measurement noise and structural systems. In this paper, a time domain load identification method based on Gibbs sampling and a hybrid dynamic load identification method based on Bayesian and interval analysis are proposed. Firstly, the structural model error is considered as the overall Markov parameter matrix error, and the measurement noise is calculated together; secondly, considering the structural model error as interval parameter, the upper and lower load boundaries are obtained by combining interval analysis with Gibbs sampling method based on Taylor expansion. It is shown that the Gibbs
gao, bo, Liu PhD, Xiaoang
Development of Biomechanical Computational Models of Six-year-old Child Occupant with Different Sitting Postures and Application in the Study of Whiplash Injuries2022-01-105203/29/2022
Whiplash injury is one of the main types of child occupant neck injuries in traffic accident. With the development of intelligent cockpit, child occupants will engage in traffic operation in various sitting positions. 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 position 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
Li, Haiyan, Wang, Yanxin, He, Lijuan, Lv, Wenle, Cui, Shihai, Ruan, Jesse Shijie
Integrated Wheel Assembly Designing and optimization for BAJA SAE ATV 2022-01-095203/29/2022
The conventional Wheel assembly is optimized using Stub and Hub integration by researching and evaluating new assembly designs, Material selection using Charpy impact test on different materials (EN24, 20MNR5, EN36) with different hardening processes (through hardening, Carburizing) are evaluated for the best combination of material and type of hardening which absorbs highest impact energy, which further evaluated for different types of brittle and ductile failure on those specimens, Component designing is performed considering various boundary condition evaluated for BAJA SAE ATV which includes Bump force due to hill fall down, Tension/Compression generation in case of improper landing on wheels, Torsion transfer through axle and Lateral forces due to centrifugal forces were used for design calculation and then FEA is used for Design validation. Finite model is generated in Hypermesh using various Meshing techniques considering rotating symmetry for achieving good quality criteria
Bhardwaj, Vasu
Seatback Strength and its Effect on In Position and Out of Position ATD Loading in High-Speed Rear Impact Sled Tests 2022-01-103803/29/2022
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 approximately 100-msec duration pulse 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 pulse was designed to represent a severe rear impact crash involving modern vehicles. 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 combinations of tests evaluated the
Croteau, Jeffrey, Toney-Bolger, Megan, Isaacs, Jessica L., Shurtz, Ben, Zolock, John
Investigations of Honeycomb and Foam structures of Automotive Front rails During Frontal crashes and its affinity with Optimum Energy Absorption2022-01-104903/29/2022
Energy dissipation in frontal crash of the vehicles normally occurs through the deformation in the engine compartment zone and especially on longitudinal front rails. In this article, the details of the crash tests is presented which involves an interpretation of the damage profiles and understanding the origin of the stiffness coefficients in main particular member which is front rails of a passenger vehicle. Moreover, the present experimental work is used to estimate the energy dissipated during deformation based on crush measurements. Furthermore, it explains the implementation of experimental test to investigate the influence of design characteristics on the deformation behavior of the proposed front rails. The current experimental work deals with the influences of geometric shape modifications of conventional steel members with flange configurations compared to honeycomb structures and structural foam with the same members length. The observations in this work led to conclude the
Elhussieny, Sayed Abbas, Oraby, Walid
Rear-End Impacts – Part 1: Field and Test Data Analysis of Crash Characteristics 2022-01-104103/29/2022
Prior to developing or modifying the protocol of performance evaluation tests, it is important to identify field relevant conditions. The objective of this study was to assess the distribution of selected crash variables from rear crash field accidents involving modern vehicles. The exposure and serious-to-fatal injury of non-ejected occupants was determined in 2008+ model year (MY) vehicles using 2007-2015 NASS-CDS and 2017-2019 CISS. In addition, 15 EDRs were collected from 2017 to 2019 CISS cases with a rear delta V ranging from 32 to 48 km/h. Ten rear crash tests were also investigated to identifying pulse characteristics in rear crashes. The tests included five vehicle-to-vehicle crash tests and five FMVSS 301R barrier tests matching the struck vehicle. The analysis of NASS-CDS and CISS data indicates that more than 50% of exposed (MAIS 0+F) occupants were involved in a rear crash with a distributed impact and with no over-ride or under-ride. More than 93% were with a 6 o’clock
Parenteau, Chantal, White, Samuel, Burnett, Roger, Stephens, Gregory, Michalski, David
A Study on the Robust Crash Performance Structure of Continuous Fiber Thermoplastic Composite Cowl Crossbar2022-01-105603/29/2022
Since the 1990s, an increasing amount of research has been done in the automotive industry, not only to improve vehicle production efficiency and performance but also for environmental preservation and enhanced recycling. For this reason, recently, keen interest has been focused on the reduction of fuel consumption through the development of eco-friendly and weight-effective vehicles. This is due in part to the strengthening of regulatory standards for fuel efficiency in each country. This study will focus on the high crash safety performance and the optimization of the IP module, in particular, the cowl crossbar, which in most vehicles, can account for more than 33% of the total weight. In fact, the cowl crossbar is the main part of the vehicle that must support the duct system, steering column module as well as the entire IP module. Therefore, it requires a high stiffness to meet the performance requirements for NVH, durability, and crash protection. For example, during a frontal
Kim, Heeseok, KIM, IL SANG, JAE HYUN, AN, IN SOO, HAN, CHOI, IKKEUN, Park, Sanghyeon
Validation of Utilizing a Self-Propelled Crash Sled to Simulate Occupant Accelerations in Minor Rear-End Impacts2022-01-104003/29/2022
A novel, electrically self-propelled, mobile, free-standing crash sled was constructed with a relatively minimal budget (i.e., ≤ $10,000). The crash sled was designed to simulate occupant driver or passenger seat movement in minor impacts at varying angles with minimal, if any, component replacement necessary between tests. Validation of the crash sled in a rear-end only configuration for determination of occupant accelerations was performed. Minor rear-end crash tests involving human occupants were conducted utilizing a 2007 Toyota Camry target vehicle and a 2005 Toyota Camry bullet vehicle with changes in velocity for the target vehicle ranging between 2.8 km/h and 7.7 km/h. Vehicle instrumentation consisted of tri-axial accelerometers affixed to the center tunnels near their respective center of gravities. Human occupant instrumentation occurred only in the target vehicle and involved tri-axial accelerometers at the head, thorax, and lumbar spine. Peak longitudinal head and lumbar
Vigil, Cole Mackenzie, Salboro, Conrad, Jones, Brian, Brink, Justin, Jorgensen, Michael, Swinford, Scott
Crash Test Methodology for Electric Scooters with Anthropomorphic Test Device (ATD) Riders2022-01-103303/29/2022
As micromobility devices (i.e., e-bikes, scooters, skateboards, etc.) continue to increase in popularity, there is a growing need to test these devices for purposes ranging from use in crash reconstruction to design of new products. Although tests have been conducted across the industry for electric scooters (e-scooters), this paper describes a novel method for crash testing e-scooters with anthropomorphic test devices (ATDs) “riding” them, providing new sources for data collection and research. A sled fixture was designed utilizing a pneumatic crash rail to propel the scooters with an overhead gantry used for stabilization of the ATD until release just prior to impact. The designed test series included impacts with a 6-inch curb at varying incident angles, a stationary vehicle, and a pedestrian ATD. Test parameter permutations included changing wheel sizes, impact speeds, and safety equipment. One of the primary focuses of this testing was to establish a methodology which provided
Como, Steven Gerard, Paradiso, Marc, Campbell, Ian C., Garman, Christina, Werner, Stephen, Wishart, Jeffrey
Effect of Decoration on Windshield Impact Resistance and Novel Decoration Solution Compatible with Chemical Strengthening2022-01-030403/29/2022
Ball bearing impact tests were performed to evaluate impact resistance of laminates with different decoration configurations. Test results showed that laminates made with enamel decorative frit only on Surface 4, significantly outperformed laminates that had enamel on Surface 2. Furthermore, it was found that hybrid laminates, consisting of a standard annealed outer-ply and a thin, chemically strengthened inner-ply with a specially formulated decorative frit which is compatible with the ion-exchange chemical strengthening process, resulted in impact resistance levels that were three times greater than conventional laminates. Details follow.
Cleary, Thomas, Huten, Timothy, Lehuede, Philippe, Joubaud, Laurent, Friske, Mark
Steering Control Systems - Heavy TrucksJ2425_202111 (Current)11/09/2021
This SAE Recommended Practice describes a laboratory test procedure and requirements for evaluating the characteristics of heavy-truck steering control systems under simulated driver impact conditions, as well as driver entry/egress conditions. The test procedure employs a torso-shaped body block that is impacted against the steering wheel.
Truck Crashworthiness Committee
Steel, Bars, Forgings, and Tubing 1.2Cr - 2.0Ni - 0.45Mo (0.27 - 0.33C)AMS6407L (Current)10/22/2021
This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.
AMS E Carbon and Low Alloy Steels Committee
Steel, Bars, Forgings, and Tubing 1.2Cr - 2.0Ni - 0.45Mo (0.27 - 0.33C)AMS6407L-TEST-REC (Historical)10/22/2021
This specification covers an aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.
AMS E Carbon and Low Alloy Steels Committee
Improving Pedestrian Automatic Emergency Braking2021-01-126510/11/2021
Abstract: Most new vehicles sold in 2018 (56%) had, as either a standard or optional feature, Advanced Driver Assistance Systems (ADAS) equipped with Pedestrian Automatic Emergency Braking (AEB). However, current testing protocols implemented by safety organizations and programs, such as Euro NCAP, NCAP, and IIHS largely do not evaluate the performance of PAEB in dark conditions without streetlights. This is true despite data from the National Highway Traffic Safety Association (NHTSA) showing that more pedestrian fatalities occur in dark conditions without streetlights than in daylight conditions. Additionally, independent tests conducted by NHTSA and the American Automobile Association (AAA) reveal that, in every scenario considered, PAEB systems frequently fail to protect pedestrians in dark conditions. Within this context, to encourage improvement in PAEB performance and increase nighttime pedestrian safety, this paper includes the following sections: 1. A proposal for the
Naikal, Nikhil
Flexible Pedestrian Legform Impactor [FlexPLI] - Examination for its Repeatability & Reproducibility2021-26-001109/22/2021
Recently, the Flexible Pedestrian Legform Impactor (or Flex-PLI) – an advancement over the existing EEVC legform – was included in the Global Technical Regulation for Pedestrian Safety viz. GTR-9. The legform tool undergoes impact testing with vehicle at 40kmph in order to evaluate the frontal structure of vehicle for Pedestrian Safety. Being more biofidelic design over the old EEVC legform, Flex-PLI is more flexible and sensitive towards different vehicle designs, shapes and inner bumper structure. This flexibility and sensitiveness of its design also calls for examining the Manufactured FlexPLI for its efficacy under impact testing in terms of its Durability, Repeatability and Reproducibility. This study aims at validating the performance of the test device by building a platform for computing the variations in test results. In this study, Three key aspects are identified to measure the performance of this device – Durability, Repeatability, and Reproducibility. Through extensive
Jain, Subhav, Lamba, Rahul, Kumar, Manoj
Innovative method of Child injury performance Optimization using Sled tests2021-26-000809/22/2021
¬¬¬Child injury performance evaluation is becoming critical part of almost all legal and consumer based vehicle safety evaluation protocols. Most of New CAR Assessment Protocols (NCAP) now have separate ratings exclusively to evaluate Child restraint system effectiveness and Child dummy performance under various crash testing modes. OEM’s have need and challenge of maximizing injury performance. Sled tests are conventionally used for tuning restraints like seat belts and airbags for driver and co driver under various frontal type test conditions. However second row seats are used for CRS/ Child injury performance evaluations. In the present study an attempt is made to simulate child injury performance of P3 dummy positioned on second row seat on defined child seat for 64 kmph frontal Offset deformed barrier type test confirming to Global NCAP. Sled pulses are carefully tuned to capture key injury patterns. Thence restraint parameters are tuned to improve child dummy injuries
Shanbhag, Ganesh
Analysis of Crash Data from a 2012 Hyundai Genesis Coupe Event Data Recorder2021-01-090504/06/2021
2012 Hyundai Genesis Coupes were manufactured with Airbag Control Modules (ACMs) with Event Data Recorder (EDR) functionality to record crash-related data. However, 2013 is the first model year supported by the download tool and software manufactured for Hyundai vehicles and distributed by Global Information Technologies (GIT) America, Inc. Prior published research has shown that EDR data can be collected from pre-2013 Hyundai vehicles using the GIT tool and some data elements from 2012 and earlier model year Hyundai vehicles are accurately translated - most notably, vehicle speed. To specifically examine the EDR data recorded by a 2012 Hyundai Genesis Coupe, two instrumented crash tests were conducted. Both tests involved broadside impacts into a second stationary vehicle and resulted in a non-deployment EDR recording. The Hyundai was human driven during both crash tests. EDR data was obtained from the Hyundai following each crash test by using a vehicle identification number (VIN
Vandiver, Wesley, Anderson, Robert
Seat Performance in Rear Impacts: Seatback Deflection and Energy Dissipation2021-01-091604/06/2021
Occupant protection in rear crashes is complex. While seatbelts and head restraints are effective in rear impacts, seatbacks offer the primary restraint component to front-seat occupants in rear impacts. Seatback deflection due to occupant loading can occur in a previous rear crash and/or in multiple-rear event crashes. Seatback deflection will in-turn affect the plastic seatback deformation and energy absorption capabilities of the seat. This study was conducted to provide information on seatback deflection and seat energy consumption in low and high-speed rear impacts. The results can be used to examine seatback deflection and energy consumed in a previous rear impact, or in collisions with multiple rear impacts. Prior seatback deflection and energy absorption can affect the total remaining energy absorption and seat performance for a subsequent rear impact. Rear sled tests included eight 16 km/h tests conducted with the BioRID and eight matched 40 km/h tests with the 50th percentile
White, Samuel, Parenteau, Chantal, Burnett, Roger
Effect of ATD Size, Vehicle Interior and Restraint Misuse on Second-Row Occupant Kinematics in Frontal Sled Tests2021-01-091404/06/2021
Interest in rear-seat occupant safety has increased in recent years. Information relevant to rear-seat occupant interior space and kinematics are needed to evaluate injury risks in real-world accidents. This study was conducted to first assess the effect of size and restraint conditions, including belt misuse, on second-row occupant kinematics and to then document key clearance measurements for an Anthropomorphic Test Device (ATD) seated in the second row in modern vehicles from model years 2015-2020. Twenty-two tests were performed with non-instrumented ATDs; three with a 5th percentile female Hybrid III, 10 tests with a 10-year-old Hybrid III, and 9 tests with a 6-year-old Hybrid III. Test conditions included two sled bucks (mid-size car and sport utility vehicle (SUV)), two test speeds (56 and 64 km/h), and various restraint configurations (properly restrained and improperly restrained configurations). Head and knee trajectories were assessed. Head excursion was 38 percent greater
Parenteau, Chantal, Burnett, Roger, Danthurthi, Sri Sai Kameshwari, Andrecovich, Christopher
Incidence and Mechanisms of Head, Cervical Spine, Lumbar Spine, and Lower Extremity Injuries for Occupants in Low- to Moderate-Speed Rear-End Collisions2021-01-090004/06/2021
Automotive accidents and subsequent personal injury claims incur substantial costs annually. While seat and head restraint design continue to evolve and improve, occupant safety and injury risk assessment in rear-end collisions remain at the forefront of automotive innovation. In this study, we combined statistical analyses of nine years (2007-2015) of data from the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) database and one year (2017) of data from the Crash Investigation Sampling System (CISS) database with data acquired from vehicle-to-vehicle crash tests conducted with instrumented anthropomorphic test device (ATD) occupants. Together, these analyses were used to compare and relate field injury rates with potential mechanisms underlying head, cervical spine, lumbar spine, and lower extremity injuries in low-to moderate-speed rear-end collisions. First, we performed statistical analyses of the NASS-CDS and CISS databases to estimate the rate of AIS 2
Davis, M., Mkandawire, C., Brown, T., Pasquesi, S.
Mechanical Anisotropy and Strain-Rate Dependency of a Large Format Lithium-Ion Battery Cell: Experiments and Simulations2021-01-075504/06/2021
In order to get a better understanding of the mechanical behavior of lithium-ion battery cells, especially for the mechanical anisotropy and dynamic effect, a series of tests for quasi-static indentation and dynamic impact tests has been designed. In the study, mechanical indentation tests with different indentation heads, different loading directions and different impact speeds were performed on a type of large format prismatic lithium-ion battery cells and jellyrolls of them. To mitigate thermal runaway, only fully-discharged cells and jellyrolls were used. The force-displacement response and open circuit voltage (OCV) were recorded and compared. It shows that jellyroll and battery cell have apparent mechanical anisotropy and strain-rate effect. The stiffness of jellyroll and cell in out-of-plane direction is much larger than that in two in-plane directions. Apparent strain-rate effect can also be observed in out-of-plane direction while the reaction force changes little in in-plane
Zhu, Lingxiao, Ge, Yulong, Wang, Lin, Zhang, Lei, Liu, Yuanjie, Xia, Yong
Modeling and Predicting Mechanically Induced Internal Short Circuits in Lithium Ion Battery Packs2021-01-075004/06/2021
As advances in electrification continue within the vehicle industry, improving the front-end design process and managing the safety aspects of lithium-ion batteries is increasingly important. Structural damage to lithium-ion batteries can cause internal short circuit, leading to a large energy release that can lead to fire and thermal runaway that propagates throughout the battery pack. Southwest Research Institute has developed a mechanical model that can accurately predict mechanically-induced damage to lithium-ion battery cells and battery packs. This model also predicts whether the external damage will cause an internal short-circuit. This modeling process was illustrated using 21700 cylindrical cells with NCA cathode chemistry. High-speed impact tests were used to calibrate a single cell model, which was then scaled to a 12-cell battery module. This model was then used to accurately predict the outcome of an impact test on a 72-cell battery module. A pack homogenization method
Hoffmeyer, Matthew, Surampudi, Bapiraju
Dual-Recliner ABTS Seats in Severe Rear Sled Testswith the 5th, 50th and 95th Hybrid III2021-01-091704/06/2021
Seat strength has increased over the past four decades which includes a transition to dual recliners. There are seat collision performance issues with stiff ABTS and very strong seats in rear impacts with different occupant sizes, seating positions and physical conditions. In this study, eight rear sled tests were conducted in four series: 1) ABTS in a 56 km/h (35 mph) test with a 50th Hybrid III ATD at MGA, 2) dual-recliner ABTS and F-150 in a 56 km/h (35 mph) test with a 5th female Hybrid III ATD at Ford, 3) dual-recliner ABTS in a 48 km/h (30 mph) test with a 95th Hybrid III ATD leaning inboard at CAPE and 4) dual-recliner ABTS and Escape in 40 km/h (25 mph) in-position and out-of-position tests with a 50th Hybrid III ATD at Ford. The sled tests showed that single-recliner ABTS seats twist in severe rear impacts with the pivot side deformed more rearward than the stanchion side. The use of dual recliners on ABTS seats prevented twist but increased the stiffness causing serious
Viano, David, Burnett, Roger, White, Samuel, Stephens, Gregory, Parenteau, Chantal
Incidence and Mechanism of Head, Cervical Spine, Lumbar Spine, and Lower Extremity Injuries for Occupants in Low- to Moderate-Speed Frontal Collisions2021-01-090204/06/2021
Automotive accidents and subsequent personal injury claims incur substantial costs annually. While three-point restraint usage, dual-stage airbags, and knee bolster and side curtain airbags have become more ubiquitous and, in some cases, governmentally mandated for front seat occupants, occupant safety and injury risk assessment continue to be at the forefront of automotive innovation. In this study, we combined analyses of the National Automotive Sampling System Crashworthiness Data System (NASS-CDS; 2007-2015) and the Crash Investigation Sampling System (CISS; 2017) with data acquired from vehicle-to-vehicle crash tests conducted with instrumented anthropomorphic test device (ATD) occupants. Together, these analyses were used to compare and relate field injury rates with potential injury mechanisms in low- to moderate-speed frontal collisions. First, low- to moderate-speed (delta-V ≤ 24 km/h) frontal crash data from NASS-CDS and CISS were analyzed to estimate the rate of AIS 2+ and
Davis, M., Mkandawire, C., Brown, T., Pasquesi, S.
Effect of Occupant Weight and Initial Position in Low-to-High Speed Rear Sled Tests with Older and Modern Seats2021-01-091804/06/2021
The average body weight of the US population has increased over time. This study investigates the effect of increasing weight on seat and occupant responses in 15-18 km/h and 42 km/h rear sled tests. The effect of initial occupant posture is also discussed. Seven tests were conducted with lap-shoulder belted ATDs (anthropometric test device) placed on older and modern driver seats. Four tests were conducted with a 50th percentile male Hybrid III, two with 95th percentile male Hybrid III and one with a BioRID. The ATDs were ballasted to represent a Class I or II obese occupant in three tests. The tests were matched by seat model and sled velocity. The effect of occupant weight was assessed in three matches. The results indicated an increase in seatback deflection with increasing occupant weight. For example, the average dynamic deflection was 2.8-times greater with a ballasted 95th ATD than with a 50th ATD (20.2 v 7.3 degree) in the 15-18 km/h sled tests and 1.4-times greater with a
Parenteau, Chantal, Burnett, Roger, Viano, David, White, Samuel
Occupant Restraint System Evaluation - Lateral Rollover System-Level Heavy TrucksJ2426_202103 (Current)03/01/2021
This SAE Recommended Practice describes the test procedures for conducting simulated dynamic lateral rollover restraint system tests for heavy truck applications. Its purpose is to establish recommended test procedures that will standardize restraint system testing for heavy trucks. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.
Truck Crashworthiness Committee
Smart Fabric Detects and Collects Space DustTBMG-3850902/01/2021
Researchers have developed an acoustic fabric so sensitive to vibrations that it can detect impacts from microscopic high-velocity space particles. A terrestrial application of these fabrics could be for blast detection and in the future, to act as sensitive microphones for directional gunshot detection.
Occupant Restraint Dynamic System Evaluation - Frontal Impact Heavy TrucksJ2418_202011 (Current)11/09/2020
This SAE Recommended Practice describes the test procedures for conducting frontal impact restraint tests for heavy truck applications. Its purpose is to establish recommended test procedures that will standardize restraint system testing for heavy trucks. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.
Truck Crashworthiness Committee
The In-Depth PHEV Driveline Torsional Vibration Induced Vehicle NVH Response Study by Integrated CAE/Testing Methodology2020-01-150706/03/2020
In this paper,an amesim 1-d refined driveline model, including detailed engine, damper, dual clutch, transmission, differential, motor, halfshaft, wheel, body, suspension, powertrain mounting and powertrain rigid body, was built up, off a p2.5 topology phev,to predict torsional vibration induced vehicle NVH response addressing differing driving scenarios,like WOT rampup,parking engine start/stop,ev driving to tipnin(engine start) then to tipout(engine stop).firstly,the torsional vibration modes were predicted,addressing differing transmission gear steps of hev/ev driving mode,and the critical modes could be detected,as such, caveats/measures could be applied to setup the modal alignment chart/warn other engineering section from the very start of vehicle development; secondly,secondly,the holistic operational testing,which defined plenty measurement points including rpm fluctuation at differing location of engine/transmission,spark angle,crank position,injection angle,valve timing,MAP
zhao, Qian, zhang, Li, jia, Jianning, WU, LIE, zhuang, Huimin, Yu, Hongzhi, lu, Shouwei, zhao, honghui, poduturu, Anil, jain, Swejal, carter, Steven
A Human Body Model Study on Restraints for Side-Facing Occupants in Frontal Crashes of an Automated Vehicle2020-01-098004/14/2020
This study was to investigate kinematics and responses of side-facing seated occupants in frontal crashes of an automated minivan using Global Human Body Models Consortium (GHBMC) simplified occupant models (50th%ile male and 5th%ile female), and to develop new restraint concepts to protect the occupants. The latest GHBMC M50-OS and F05-OS models (version 2.2) were further validated with Postmortem Human Subject (PMHS) side sled tests [7]. Robustness and biofidelity of the GHBMC human models, especially for the pelvis region, were enhanced. Using the update M50-OS and F05-OS models, we evaluated the body kinematics and injury measures of the side-facing seated occupants in frontal crashes of a minivan at severities ranging from 24 kph (15 mph) to 56 kph (35 mph). Three restraint configurations were studied: 1) no restraint; 2) lap belt only; 3) lap and head/torso restraints. Parametric studies on the restraint configurations and design parameters of each restraint were performed to
Zhao, Jay Zhijian, Katagiri, Maika, Decker, William, Lee, Sungwoo, Gayzik, Francis
An Innovative Approach to Component Testing Using an Impact Sled2020-01-133104/14/2020
Historically, crash development component testing has been conducted using gravity-based vertical drop towers. The drop tower carriage is loaded to a specified weight, raised to a specific height to achieve an energy target, and dropped onto the part. This long-used approach has significant limitations with respect to achievable speed and energy, part orientation, impact angle, useable impact surface, component size, etc. With the wide variance in simulating today’s global crash scenarios, a better approach is being developed using an impact sled. The most significant advantage of this system is that there is a much higher achievable speed and energy which can be controlled with precise accuracy. This paper will provide an overview of the impact sled test system, as well as the methodology used to conduct the testing. The overview will include the challenges faced during the development of the impact sled, as well as the need for accurate and precise component fixturing methods
Kaleto, Helen, Pinelli, Alex, Briskey, Jacob P., Gizowski, John W., Reinitz, Aaron
Evaluation of Occupant Kinematics during Low- to Moderate-Speed Side Impacts2020-01-122204/14/2020
While nearly 50 percent of occupants in side-impact collisions are in vehicles that experience a velocity change (delta-V) below 15.0 kph (9.3 mph), full scale crash testing research at these delta-Vs is limited. Understanding occupant kinematics in response to these types of side impacts can be important to the design of side-impact safety countermeasures, as well as for evaluating potential interactions with interior vehicle structures and/or with other occupants in the vehicle. In the current study, two full-scale crash tests were performed utilizing a late-model, mid-size sedan with disabled airbags. The test vehicle was impacted by a non-deformable moving barrier on the driver side at an impact speed of 10.0 kph (6.2 mph) in the first test and then on the passenger side at an impact speed of 21.6 kph (13.4 mph) in the second test, resulting in vehicle lateral delta-Vs of 6.1 kph (3.8 mph) and 14.0 kph (8.7 mph), respectively. As can occur in real-world collisions, the initial
George, Juff, Davis, Mathieu, Sharpe, Sarah, Olberding, Joseph, Imler, Stacy, Bove, Robert
Biomechanics of Passenger Vehicle Underride: An Analysis of IIHS Crash Test Data2020-01-052504/14/2020
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
Using Vehicle EDR Data to Calculate Motorcycle Delta-V in Motorcycle-Vehicle Lateral Front End Impacts2020-01-088504/14/2020
This research focuses on the use of Event Data Recorders (EDR) to assist in calculating speed loss or ΔV undergone by a motorcycle in a broadside type impact into a vehicle. If the struck vehicle has EDR data, this could be a useful tool in calculating motorcycle ΔV or corroborating motorcycle ΔV calculations from crush or other methodologies. Certain parameters critical to calculation of motorcycle ΔV must be considered, including the appropriate effective mass to use for the motorcycle/rider combination. This study used crash test data to determine a method of applying parameter values to accurately calculate motorcycle ΔV in a motorcycle-vehicle collision. In this study, three crash tests were performed in which a motorcycle with a dummy rider traveling in the range of 42 to 51 mph collided into the right front corner of a vehicle traveling between 5 and 16 mph. In all three tests, both the vehicle and motorcycle were instrumented with triaxial accelerometers and triaxial rate gyros
Fatzinger, Edward, Landerville, Jon
The Effect of Crash Severity and Structural Intrusion on ATD Responses in Rear-End Crashes2020-01-122404/14/2020
This study assesses vehicle and occupant responses in six vehicle-to-vehicle high-speed rear impact crash tests conducted at the Exponent Test and Engineering Center. The struck vehicle delta Vs ranged from 32 to 76 km/h and the vehicle centerline offsets varied from 5.7 to 114 cm. Five of the six tests were conducted with Hybrid III ATDs (Anthropometric Test Device) with two tests using the 50th male belted in the driver seat, one test with an unbelted 50th male in the driver seat, one test with a 95th male belted in the driver seat, and one with the 5th female lap belted in the left rear seat. All tests included vehicle instrumentation and three tests included ATD instrumentation. The ATD responses were analyzed and compared to corresponding IARVs (injury assessment reference values). Ground-based and onboard vehicle videos were synchronized with the vehicle kinematic data and biomechanical responses. The timing of the vehicle crush, occupant compartment intrusion, seatback motion
Parenteau, Chantal, Croteau, Jeffrey, Zolock, John
Occupant Dynamics during Moderate-to-High Speed Rear-End Collisions2020-01-051604/14/2020
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
Responses of the THOR in Oblique Sled Impacts: Focus on Chest Deflection2020-01-052204/14/2020
The National Highway Traffic Safety Administration (NHTSA) published a Request for Comments (RFC) on proposed changes to the New Car Assessment Program (NCAP) in 2015 and 2017. One potential change was the introduction of a frontal Oblique Impact (OI) crash test. The Test device for Human Occupant Restraint (THOR) in the front left seat was used in the proposed OI test. The motivations behind the current study were a) determine if OI sled tests can be simplified, b) study the sensitivity of the THOR chest deflection to the shoulder belt layout in OI and c) assess the NHTSA-proposed THOR thoracic injury risk curves. In the current study, eleven oblique sled impact tests were conducted. The environment was representative of a generic mid-sized sedan. The buck was mounted on a rigid plate that allowed the pre-test rotation of the buck relative to the sled axis. A generic mid-sized OI pulse was used. The pulse was applied in the longitudinal direction of the sled. The THOR was seated in
El-Jawahri, Raed E., Siasoco, Kevin, Ruthinowski, Rich, McCoy, Robert W., Gao, Zhenyan, Jaradi, Dean
The Effect of FMVSS 301R on Vehicle Structure in Rear Impact2020-01-122604/14/2020
Vehicle structures are designed to manage impact forces and transfer crash energy, in addition to their primary purpose of connecting all the vehicle powertrain, suspension, steering, HVAC, electronics, occupant accommodation, and weatherproofing. With the introduction of new rear impact requirements, the design of rear structures has evolved and the use of high strength steel has increased. This study objective was to assess the effect of new FMVSS 301 requirements on vehicle responses. NHTSA conducted 33 offset rear crash tests at 80 km/h with vehicles that pre-dated the newer FMVSS 301R requirements and 88 with vehicles that complied with the newer requirements, with a 2009-2015 model year range. The vehicles were grouped by size and the permanent crush was tabulated. Overall, the struck-side maximum crush decreased in the newer model vehicles. Seven matches with pre and post 301R were identified on the same make and model vehicle of different generations. The matched tests were
Parenteau, Chantal, Stephens, Gregory, Yaek, Jennifer, Gregory, Serge
Enhancement of Longitudinal Energy Absorption Efficiency in FMVSS 3012020-01-122504/14/2020
While active safety has become a focus of attention, passive safety protocols are still being updated, and evaluation standards are becoming stringent worldwide. This paper focused on FMVSS 301, the North American regulation for rear impacts. Due to an offset impact with deformable barrier, it is challenging to control bending modes of rear frames. Furthermore, there is a considerable difference in load paths to the left and right frames, and the amount of bending deformation experienced by the frame on the non-collision-side, which does not directly contact with the barrier, is low. The purpose of this research was to enhance rear-frame energy absorption efficiency in such collisions. To achieve this goal, this research focused on enhancement of deformation mode of the rear frames, and also minimizing the difference in their input loads. For the enhancement of deformation mode, the number and arrangement of collapse points were optimized, and multi-stage bending mode with a high level
Hasegawa, Atsushi, Fujii, Takayuki, Matsuura, Norikazu, Shimizu, Tomohiro
The Effects of Active and Conventional Head Restraints on Front Seat Occupant Responses in Rear Impacts2020-01-121704/14/2020
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.
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