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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Study on Transport Airplane Unplanned Water Contact</title>
      <link>https://trid.trb.org/View/2736762</link>
      <description><![CDATA[This study provides for an identification of accident scenario(s) and associated occupant risks and survival equipment needs, relating to the inadvertent or unplanned water contact of transport category airplanes. This identification was obtained, in part, from the results of contractual studies of transport accident data. The subject study concludes that while the unplanned water contact of a transport airplane occurs less frequently than corresponding ground contact, the impact loads are often higher, leading to greater fuselage damage. Also, the unplanned water contact occurs more frequently than a planned water landing (ditching) and usually involves adverse flooding conditions. These conditions, in turn, affect the ability of occupants to retrieve, deploy and/or don on-board floatation equipment.]]></description>
      <pubDate>Wed, 26 Aug 2026 12:15:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2736762</guid>
    </item>
    <item>
      <title>Crash Pulse Characterization for the Passenger Vehicle Fleet in India</title>
      <link>https://trid.trb.org/View/2761732</link>
      <description><![CDATA[A crash pulse is the signature of the deceleration experienced by a vehicle and its occupants during a crash. The deceleration-time plot or crash pulse provides key insights into occupant kinematics, occupant restraints, occupant loading and efficiency of the structure in crash energy dissipation. Analysing crash pulse characteristics like shape, slope, maximum deceleration, and duration helps in understanding the impact of the crash on occupant safety and vehicle crashworthiness.This paper represents the crash pulse characterization study done for the vehicles tested at ARAI as per the ODB64 test protocol. Firstly, the classification and characterization of the crash pulses is done on the basis of the unladen masses of the vehicles. The same are further analysed for suitability of mathematical waveform models such as Equivalent Square Wave (ESW), Equivalent Triangular Wave (ETW), Equivalent Sine Wave (ESW), Equivalent Haversine Wave (EHSW) as well as EDTW (Equivalent dual trapezia wave) or Bi Slope Approximation model for the characterization.These mathematical wave diagrams are then utilized for analysing the crash behaviour and its probable effect on the injury probability. Such a study can be used by design engineers to model the front-end stiffness of the vehicle frontal structure. This can further help to optimize the dummy restraint modifications to minimize the occupant injury.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761732</guid>
    </item>
    <item>
      <title>Geometrical Assessment of the Curtain Airbag Coverage in Indian Passenger Vehicles</title>
      <link>https://trid.trb.org/View/2761726</link>
      <description><![CDATA[Curtain airbags are the most effective protective systems to prevent severe/fatal head injuries in side collisions with narrow objects such as poles or trees. One of the important parameters of curtain airbags is the inflated zone i.e. the coverage area of the airbag, which decides the extent of head protection for occupants with different anthropometries in different seating rows.EuroNCAP first introduced the concept of Head Protection Device Assessment (HPDA) in 2015., In addition to the performance requirements in the dynamic test, EuroNCAP started assessing the deployed curtain airbag/s for its area coverage and verification of inflated zones for various anthropometries over occupant rows.In India, there is now a near total adoption of curtain airbags as standard fitment by the OEMs. Further, introduction of Bharat NCAP (BNCAP), a Perpendicular Pole Side Impact test is conducted for assessing the effectiveness of curtain airbags in a dynamic test, but currently, does not perform the HPD assessment.The paper studies the Head Protection Device/Curtain Airbags offered in Passenger Vehicles in India w.r.t. the Head Protection Device Geometric Assessment (HPDA). This assessment analyses the effectiveness of curtain airbags present in Indian passenger vehicles for protection of occupants of different anthropometries. The study is conducted on the vehicles that have been tested at ARAI and are also currently under sale in the Indian market.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761726</guid>
    </item>
    <item>
      <title>Achieving Robust Sensing Performance for Six-Airbag Systems: Design Approaches and Validation Techniques for Side Sensing</title>
      <link>https://trid.trb.org/View/2761723</link>
      <description><![CDATA[The proposal of GSR 16(E) in India promotes six airbags in passenger vehicles, aiming to enhance occupant safety. In parallel, the new Bharat New Car Assessment Program (BNCAP) outlines performance protocols that demand robust airbag deployment strategies to achieve a five-star safety rating. One of the critical challenges in meeting both regulatory and consumer safety expectations is the optimal packaging of the airbag Electronic Control Unit (ECU) and its associated impact sensors. These must perform reliably across regulatory tests, BNCAP protocols, and real-world accident scenarios.The location of side acceleration ‘g’ side impact sensors—whether mounted on the side sill, B-pillar, C-pillar, or door structures—is pivotal to achieving consistent and timely side airbag deployment. These sensors must also demonstrate immunity to false triggers or missed events in both static and dynamic misuse and abuse conditions. Ensuring robust sensor performance under these varied conditions is key to the success of the system.This study focuses on evaluating acceleration-based side impact sensors placed at different locations within the vehicle structure, assessing their sensitivity and correlation with airbag deployment performance. Additionally, for compact vehicles where faster deployment of side airbag is essential, the use of pressure-based sensors was investigated. The findings of this study were instrumental in finalizing the optimal packaging strategy for both acceleration and pressure sensors in six-airbag systems.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761723</guid>
    </item>
    <item>
      <title>Investigating Pelvic Locking and Torso Kinematics Using Human Body Models in Frontal Impact Scenarios</title>
      <link>https://trid.trb.org/View/2761710</link>
      <description><![CDATA[Occupant Safety systems are usually developed using anthropomorphic test devices (ATDs), such as the Hybrid III, THOR-50M, ES-2, and WorldSID. However, in compliance with NCAP and regulatory guidelines, these ATDs are designed for specific crash scenarios, typically frontal and side impacts involving upright occupants. As vehicles evolve (e.g., autonomous layouts, diverse occupant populations), ATDs are proving increasingly inadequate for capturing real-world injury mechanisms. This has led to the adoption of computational Human Body Models (HBMs), such as the Global Human Body Models Consortium (GHBMC) and Total Human Model for Safety (THUMS), which offer superior anatomical fidelity, variable anthropometry, active muscle behaviour modelling, and improved postural flexibility. HBMs can predict internal injuries that ATDs cannot, making them valuable tools for future vehicle safety development.This study uses a sled CAE simulation environment to analyze the kinematics of the HBMs model in a frontal crash scenario. The methodology includes the initial correlation of Hybrid III CAE simulation results with physical sled test data, followed by a comparative analysis with GHBMC M50-O v6-2 based simulations.A significant difference was observed in pelvic forward displacement between the Hybrid III and GHBMC M50-O v6-2. The difference in interaction originates from the difference in the construction of the pelvis between the Hybrid III and GHBMC. In the GHBMC, reduced displacement occurs because the pelvis locks in the seat. This interaction is absent in ATDs, resulting in increased torso rotation and a potential rise in upper extremity injury risk for HBMs.The study examines the various reasons for pelvic locking and increased upper body rotation. These evaluations aim to raise the negative consequences of pelvic locking on upper extremity injuries. The probable solutions that can reduce pelvis locking while preserving occupant stability is also discussed.The study highlights the significance of HBMs in understanding occupant interactions and supports their use in the development of next-generation restraint systems.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761710</guid>
    </item>
    <item>
      <title>Adaptive Restraints for Equitable Protection</title>
      <link>https://trid.trb.org/View/2761709</link>
      <description><![CDATA[Real-world crashes involve diverse occupants, but traditional restraint systems are designed for a limited range of body types considering the applicable regulations and protocols. While conventional restraints are effective for homogeneous occupant profiles, these systems often underperform in real-world scenarios with diverse demographics, including variations in age, gender, and body morphology. This study addresses this critical gap by evaluating adaptive restraint systems aligned with the forthcoming EURO NCAP 2026 protocols, which emphasize real-world crash diversity and occupant type. Through digital studies of frontal impact scenarios, we analyze biomechanical responses using adaptive restraints across varied occupant demographics, focusing on head and chest injury (e.g., Chest Compression Criterion [CC]). This study used a Design of Experiments (DOE) approach to optimize occupant protection by timing the actuating of these adaptive systems. The results indicate that activating adaptive seatbelts and airbags before reaching peak chest and pelvis accelerations can help reduce injuries. The study suggests a rule-based framework for adaptive restraints, demonstrating that injury optimization correlates strongly with time control of restraint parameters. These insights advance the development of occupant-centric safety systems, offering scalable solutions for emerging regulatory standards and enhancing protection for underrepresented demographics in vehicular safety engineering.]]></description>
      <pubDate>Wed, 19 Aug 2026 13:48:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2761709</guid>
    </item>
    <item>
      <title>A Comprehensive Review of System Risk in Automotive Crash
                    Safety</title>
      <link>https://trid.trb.org/View/2717214</link>
      <description><![CDATA[
                
                Occupant protection has been at the forefront of risk evaluation regarding
                    vehicle crashworthiness design. However, the vehicle is a member of a larger
                    transportation system with varied stakeholders. This article identifies an
                    opportunity for assessing risk in a crash event through emerging safety science
                    paradigms. Conventional Safety I and Safety II frameworks handle well-defined
                    hazards but falter with uncertainty, variability, and emergent behaviors in real
                    crashes. A comprehensive literature review was performed on peer-reviewed
                    research to situate automotive crash safety risk within the Safety III
                    paradigms. The review addresses two questions: (1) How is “risk” defined across
                    the crash safety literature and adjacent safety science domains? and (2) What
                    limitations arise from these definitions in practice? Findings show a dominant
                    probabilistic framing alongside a minority of system-oriented interpretations.
                    Current crash safety practice lacks a coherent, system-level definition of risk
                    that integrates uncertainty and knowledge strength, leading to fragmented
                    methods and limited alignment with modern safety science. Based on this
                    synthesis, the article proposes guiding principles for Safety III-aligned
                    guidelines and recommendations that integrate consequences, uncertainty, and
                    knowledge strength to improve transparency, traceability, and adaptability in
                    crash safety decision-making.
            ]]></description>
      <pubDate>Tue, 23 Jun 2026 13:41:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2717214</guid>
    </item>
    <item>
      <title>Integrated Evaluation of Pre-Crash Braking and Crash Injury Outcomes Using Human Body Models and ATDs</title>
      <link>https://trid.trb.org/View/2712074</link>
      <description><![CDATA[Traditionally, occupant safety research has centered on passive safety systems such as seatbelts, airbags, and energy-absorbing vehicle structures, all designed under the assumption of a nominal occupant posture at the moment of impact. However, with increasing deployment of active safety technologies such as Forward Collision Warning (FCW) and Autonomous Emergency Braking (AEB), vehicle occupants are exposed to pre-crash decelerations that alter their seated position before the crash. Although AEB mitigates the crash severity, the induced occupant movement leads to out-of-position behavior (OOP), compromising the available survival space phase and effectiveness of passive restraint systems during the crash. Despite these evolving real-world conditions, global regulatory bodies and NCAP programs continue to evaluate pre-crash and crash phases independently, with limited integration. Moreover, traditional Anthropomorphic Test Devices (ATDs) such as Hybrid III dummies, although highly repeatable, lack the bio-fidelity necessary to capture human-like kinematics during pre-crash braking events involving low g. ATDs do not simulate the spinal articulation, posture adjustments and active muscle contraction that occur during emergency maneuvers or pre-crash scenarios. To overcome these limitations, researchers have increasingly turned to Human Body Models (HBMs) such as Total Human Model for Safety (THUMS) and Global Human Body Model Consortium (GHBMC). These models enable high-fidelity finite element (FE) simulations with anatomical realism, allowing for the inclusion of active musculature and posture changes.This study aims to quantify the occupant forward excursion under pre-crash phase (due to AEB) and explore the possibility of an integrated simulation framework that evaluates occupant safety across both pre-crash and crash events. For this, the approach was to carry out full vehicle braking tests (1g braking pulse) with adult male (AM50) volunteers at different speeds to measure forward head excursion during pre-crash. These scenarios were replicated in LS-Dyna using THUMS HBM, showing strong agreement with experimental data. The resulting excursed postures were then used in crash simulations with ATDs to evaluate the effect on injury outcomes. Overall, the findings demonstrate effect of forward excursion on occupant injuries and the effectiveness of HBMs in capturing occupant kinematics, during pre-crash events.]]></description>
      <pubDate>Wed, 10 Jun 2026 17:05:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2712074</guid>
    </item>
    <item>
      <title>Effective Design Method for Lightweight Suite of Seats Considering Crashworthiness and Cost</title>
      <link>https://trid.trb.org/View/2692240</link>
      <description><![CDATA[This paper presents a methodology for designing and evaluating lightweight, crashworthy aircraft seats that meet 21g crash safety standards and injury criteria. Four seat classes—double economy, single economy, premium economy, and business—were developed using a modular design strategy focused on part commonality (family of parts) and manufacturability. A shared family of structural components was implemented across all seat types, with dimensional modifications applied only, when necessary, due to differences in seat width or height. In such cases, the same material systems and design principles were used to ensure consistency and reduce manufacturing complexity. The designs were evaluated using finite element simulations to verify performance under aerospace crash conditions. Each seat configuration was validated against regulatory crashworthiness criteria and injury thresholds, including pelvic, lumbar, and femur compressive forces, as well as head injury criteria (HIC) values. The final designs successfully passed all crash and most injury thresholds, achieving regulatory compliance while maintaining a lightweight structure. This marked a significant improvement over a baseline seat configuration that failed to meet crash or injury requirements. By combining modularity with performance-driven design, this approach delivers a flexible and manufacturable seat family that balances safety, weight, and cost. The methodology offers broader applicability for occupant protection systems in automotive and aerospace domains, where lightweighting and regulatory compliance remain critical design challenges.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692240</guid>
    </item>
    <item>
      <title>Enhanced CAE Methodology to Predict Bolt Shear Failure Using Multi-Layer Approach</title>
      <link>https://trid.trb.org/View/2692122</link>
      <description><![CDATA[Automotive seat system is one of the most complex systems in vehicle for its technical and functional requirements. Seat is designed to meet all regulatory requirements subjecting it to multiple tests with loading patterns which caters to the occupant safety. Varied loading and load path for different test requirements cause seat bolts to experience tensile, compressive, bending moments and shear loading. Shearing along bolt length is one of the common failure modes observed during design validation by physical tests.In the world of CAE, there is an industry approach to find the bolt failures at nut and head for all kind of loads. But shear failures along varied bolt lengths are not accurately predictable as multiple sheet metal parts will transfer loads unevenly onto bolt length and it becomes challenge to find which component is leading to shear failure. Hence by adding multiple rupture layers across the bolt length shear and its location could be predicted. Further, to resolve the bolt shear issues, engineers generally try to modify the component design for better energy absorption, but our research found that, only by increasing the clearance around bolt hole will resolve the bolt shear issues.During one of such failures, a new approach of adding multiple rupture layers along bolt length was used which predicted the shear failure modes and location of shear as observed in physical tests. The CAE bolt model thus updated with new procedure for all such future bolt shear failure prediction in seat structure models.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692122</guid>
    </item>
    <item>
      <title>Revisiting Rear Seat Safety: Field Evaluations of Relative Injury Risk Across Seating Positions and the Integration of Advanced Rear Seat Belt Systems</title>
      <link>https://trid.trb.org/View/2692085</link>
      <description><![CDATA[Despite advances in crash avoidance, occupant restraint systems remain crucial in protecting the motoring public. Following decades of improvement in occupant protection, including several supplemental restraint systems for front seat occupants, the safety of rear seat occupants has recently undergone scrutiny. Studies evaluating rear seat occupant injury risk via field crash data have reported reduced relative safety in rear seating positions and alluded to advanced rear seat restraints, such as pretensioners and load limiters, as potential solutions. While the pursuit of novel technologies has historically improved occupant outcomes, evaluation of new systems in both controlled laboratory environments and field crashes is necessary to understand potential consequences of widespread introduction. This study analyzed the prevalence of advanced seat belts (load limiters and pretensioners) in the rear seating positions in the U.S. fleet. Additionally, occupant injury risk was compared across vehicles equipped with conventional and advanced seat belts in the rear seat, as well as between rear and front seat occupants, using data from state crash databases. The proportion of vehicles equipped with advanced rear seat restraints has steadily increased over the past couple of decades, but, as of 2023, remained below 10% of registered vehicles on US roadways. Evaluation of police-reported field crash data indicated that lap-shoulder belted rear seat occupants sustained fatal or incapacitating injury at a lesser rate than front seat occupants. Rear seat occupants have historically been and remain well-protected. Current field data do not consistently demonstrate a statistically significant reduction in rear seat occupant injury or fatality risk attributable to advanced seat belts. However, the relatively low number of crashes involving serious injury or fatality for rear-seated occupants in vehicles equipped with these systems underscores the need for additional data to fully evaluate their effectiveness in real-world crashes.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692085</guid>
    </item>
    <item>
      <title>Potential Regulatory Approaches for Occupant Safety in Automated
                    Vehicles with Unique Seating Configurations – Part 1: Occupant Protection
                    Proposals</title>
      <link>https://trid.trb.org/View/2692083</link>
      <description><![CDATA[Some Automated / Autonomous Vehicles (AVs) have unique seating configurations                     (stagecoach and campfire seating) which present expanded occupant safety                     challenges. Significant portions of the National Highway Traffic Safety                     Administration (NHTSA) Federal Motor Vehicle Safety Standards (FMVSS) do not yet                     align with AVs containing unique seating. This paper series takes the NHTSA                     occupant safety standard approach for conventional forward-facing seat vehicles                     where many compliance evaluations are in the frequently occupied front row and                     expands it to stagecoach and campfire AVs where the rear seating row is                     anticipated to be frequently occupied. The approaches proposed are from a                     logic-based safety-focused analysis and in many cases previously published                     material. The goal of this paper series is to offer regulatory proposals that                     enable equivalent performance for these AVs to existing forward-facing seating                     vehicle occupant safety standards and meet Executive Order 13045 on child                     safety.Part 1 (this paper) focuses on occupant protection for the front and rear seating                     rows in stagecoach and campfire seating AVs for: front impacts (FMVSS-208),                     windshield mounting (FMVSS-212), windshield glazing (FMVSS-219), rear impacts                     (FMVSS-301/305), head restraints (FMVSS-202a), head impacts (FMVSS-201), side                     impacts (FMVSS-214), roof crush (FMVSS-216a), ejection mitigation (FMVSS-226),                     and door pinch (a potential FMVSS-118 addition).Some of the proposals address occupant performance for vehicles without                     traditional leg and restraint reaction surfaces. In addition, an interior safety                     sensing approach that assesses if occupants are properly restrained before a                     ride can begin is proposed as an alternative / a replacement for unbelted                     in-position occupant performance compliance evaluations. This document also                     provides regulatory condition thoughts for AVs without a usable driver seat                     location.Part 2 (SAE paper 2026-01-0576) discusses interior safety sensing and associated                     messaging.These approaches can be used in industry-wide regulatory next step contemplation                     and deliberation for unique interior seating arrangement AVs, including public                     discussions, safety research, approach proposal development, and rulemaking                     efforts.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692083</guid>
    </item>
    <item>
      <title>Statistical Assessment of Pretensioner and Load Limiter Effects on the Large Omnidirectional Child ATD Response in Frontal Impacts</title>
      <link>https://trid.trb.org/View/2692072</link>
      <description><![CDATA[Enhancing child occupant protection requires a clear understanding of how seatbelt restraint parameters influence crash injury metrics. Real-world vehicles mostly include pretensioner and load limiter technologies to mitigate injuries, but rear seat restraints often do not include these. The FMVSS No. 213 test bench closely represents current restraint systems but does not involve such active vehicle restraint features. This study explores the response of the Large Omnidirectional Child ATD to evaluate potential injury mitigation under FMVSS No. 213 frontal sled test conditions. A simulation-based full factorial design was implemented in LS-DYNA to vary pretensioner retraction, retractor load-limiting thresholds, and webbing payout, with injury measures including head acceleration, head excursion, chest compression, and abdominal pressure twin sensors (APTS). Statistical evaluation using analysis of variance (ANOVA) and Tukey-Kramer post-hoc tests quantified main and interaction effects. Pretensioners consistently reduced head excursion and acceleration, while load limiters lowered chest compression but increased excursion, illustrating a performance trade-off. Webbing payout behavior showed strong coupling to load-limiting thresholds, revealing notable parameter interdependencies. These results demonstrate that integrating pretensioners and load limiters into child restraint systems could yield meaningful safety benefits but must be optimized holistically to balance competing injury metrics. The study provides both empirical insight and a statistical framework for evaluating advanced restraint configurations in pediatric occupant simulations.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692072</guid>
    </item>
    <item>
      <title>Quasi-Static Head Restraint Pull-Tests to Assess Retention Performance: Maximum Load and Damage Characteristic</title>
      <link>https://trid.trb.org/View/2692062</link>
      <description><![CDATA[Head restraint requirements and designs have evolved to minimize the delay in head support and reduce differential loading in the neck. As a result, head restraints have become bigger and more angled forward, sitting, closer to the occupant’s head. Head restraints separation from seatbacks are sometimes observed in the field. Are head restraint detachments resulting from occupant comfort issues prior to the crash, occupant loading during the crash or were they removed by emergency personnel for extrication? Understanding the retention strength of head restraints and the type of evidence left behind by a forced removal may help researchers resolve the question of how a head restraint may be found post-crash separated from the seat.Quasistatic pull tests were conducted to measure vertical retention capabilities, compare vertical adjustment and release mechanisms, and document deformation and damage. Eighteen different front seat head restraint designs were evaluated. The model years ranged from 2014 to 2019. All head restraints complied with FMVSS 202A requirements. Each head restraint design was tested in two tension loading configurations: In-line nominal pull and 45-degree pull. In the nominal configuration, the head restraints were pulled vertically upwards, in line with the adjustment posts. Additionally, head restraints were pulled at a 45-degree angle to the ground in the 45-degree configuration.The force at detachment averaged 1,758 ± 559 N for the in-line tests and 2,505 ± 662 N for the 45 degree pull tests. Damage was observed in all 36 tests and was evidenced by deformation in the locking mechanism and/or the guide sleeve being displaced out of the seatback. Detachment occurred due to overload or deformation of the locking mechanism or the guide sleeve being pulled out of the seatback. Bypassing detachment occurred in 21 of the tests while detachment from guide sleeve separation resulted in 15 of the tests. Half of the head restraints were equipped with two locking sides and half with one side. However, there does not appear to be a correlation between peak force and number of locking sides.There are currently no head restraint retention regulations for tensile loading. This study is a first to document head restraint separation resulting from forceful loading. The damage was documented in detail. This information may assist in answering the questions posed above.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692062</guid>
    </item>
    <item>
      <title>Machine Learning Based Meta-Analysis of IIHS Moderate Overlap Frontal Crash Test for Rear Seat Occupant Safety Performance</title>
      <link>https://trid.trb.org/View/2692058</link>
      <description><![CDATA[A machine learning (ML)-based meta-analysis was conducted to evaluate rear seat occupant safety performance in the Insurance Institute for Highway Safety (IIHS) Moderate Overlap Frontal (MOF) 2.0 crash test. ML models were trained on historical IIHS crash test data to predict rear passenger injury metrics using vehicle architecture, restraint system characteristics, crash pulse parameters, and vehicle kinematics as input features. The models demonstrated high predictive accuracy and were subsequently used in a Sobol sensitivity analysis to identify critical design parameters influencing injury outcomes.The analysis revealed that rear passenger injury metrics were most sensitive to restraint system parameters. Specifically, crash pulse magnitude was the dominant factor for head injury metrics, pretensioner activation time for neck tension force, and lap belt force for the Neck Injury Criterion (Nij). For chest-related metrics—sternum deflection, dynamic belt position, and maximum belt position—the initial belt position emerged as the most influential factor.This study demonstrates the potential of ML models to uncover dominant injury mechanisms and critical design parameters without explicitly encoding biomechanical knowledge. The findings also offer actionable insights to guide future vehicle safety design improvements for rear seat occupants.]]></description>
      <pubDate>Tue, 14 Apr 2026 15:11:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692058</guid>
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