Stapp car crash journal最新文献

{"title":"Isolated Rib Response and Fracture Prediction for Young Mid-Size Male, Enabled by Population Specific Material Models and Rib Cross-Sectional Geometry.","authors":"Miguel A Corrales, Sven Holcombe, Amanda M Agnew, Yun-Seok Kang, Duane S Cronin","doi":"10.4271/2024-22-0005","DOIUrl":"10.4271/2024-22-0005","url":null,"abstract":"<p><p>Thorax injury remains a primary contributor to mortality in car crash scenarios. Although human body models can be used to investigate thorax response to impact, isolated rib models have not been able to predict age- and sex-specific force-displacement response and fracture location simultaneously, which is a critical step towards developing human thorax models able to accurately predict injury response. Recent advancements in constitutive models and quantification of age- and sex-specific material properties, cross-sectional area, and cortical bone thickness distribution offer opportunities to improve rib computational models. In the present study, improved cortical and trabecular bone constitutive models populated with age-specific material properties, age- and sex-specific population data on rib cross-sectional area, and cortical bone thickness distribution were implemented into an isolated 6^th rib from a contemporary human body model. The enhanced rib model was simulated in anterior-posterior loading for comparison to experimental age- and sex-specific (twenty-three mid-size males, age range of 22- to 57-year-old) population force-displacement response and fracture location. The improved constitutive models, populated with age-specific material properties, proved critical to predict the rib failure force and displacement, while the improved cortical bone thickness distribution and cross-sectional area improved the fracture location prediction. The enhanced young mid-size male 6^th rib model was able to predict young mid-size male 6^th rib experimental force-displacement response and fracture location (overpredicted the displacement at failure by 35% and underpredicted the force at failure by 8% but within ±1 SD). The results of the present study can be integrated into full body models to potentially improve thorax injury prediction capabilities.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"68 ","pages":"89-103"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142629828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of A-Pillar Blind Spots on a Driver's Pedestrian Visibility during Vehicle Turns at an Intersection.","authors":"Yasuhiro Matsui, Shoko Oikawa","doi":"10.4271/2024-22-0002","DOIUrl":"10.4271/2024-22-0002","url":null,"abstract":"<p><p>This study aims to elucidate the impact of A-pillar blind spots on drivers' visibility of pedestrians during left and right turns at an intersection. An experiment was conducted using a sedan and a truck, with a professional test driver participating. The driver was instructed to maintain sole focus on a designated pedestrian model from the moment it was first sighted during each drive. The experimental results revealed how the blind spots caused by A-pillars occur and clarified the relationship between the pedestrian visible trajectory distance and specific vehicle windows. The results indicated that the shortest trajectory distance over which a pedestrian remained visible in the sedan was 17.6 m for a far-side pedestrian model during a right turn, where visibility was exclusively through the windshield. For the truck, this distance was 20.9 m for a near-side pedestrian model during a left turn, with visibility through the windshield of 9.5 m (45.5% of 20.9 m) and through the passenger-side window of 11.4 m (54.5% of 20.9 m). Additionally, we quantified the trajectory distances where pedestrians became invisible when the driver's view was obstructed by A-pillars. The sedan exhibited the highest invisibility rate at 46.1% for a far-side pedestrian model during a right turn, followed by the truck at 17.8% for the same model. These findings will be instrumental in developing new driving support systems aimed at enhancing visibility in situations where pedestrians are obscured by A-pillars.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"68 ","pages":"14-30"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142297161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of THOR-AV 5F Biofidelity in Sled Test Conditions with A Semi-Rigid Seat.","authors":"Z Jerry Wang, John Humm, Hans W Hauschild","doi":"10.4271/2023-22-0004","DOIUrl":"10.4271/2023-22-0004","url":null,"abstract":"<p><p>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); and 45° seatback, 32 km/h (BRS = 0.93). In the fourth test condition, 45° seatback, 15 km/h, the dummy demonstrated good biofidelity with a BRS score of 1.06. The dummy demonstrated good durability. No damage was identified with a full inspection conducted after the tests.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"78-111"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140852043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Examination of Crash Injury Risk as a Function of Occupant Demographics.","authors":"Dainius Dalmotas, Aline Chouinard, Jean-Louis Comeau, Alan German, Glenn Robbins, Priya Prasad","doi":"10.4271/2023-22-0002","DOIUrl":"10.4271/2023-22-0002","url":null,"abstract":"<p><p>The objectives of this study were to provide insights on how injury risk is influenced by occupant demographics such as sex, age, and size; and to quantify differences within the context of commonly-occurring real-world crashes. The analyses were confined to either single-event collisions or collisions that were judged to be well-defined based on the absence of any significant secondary impacts. These analyses, including both logistic regression and descriptive statistics, were conducted using the Crash Investigation Sampling System for calendar years 2017 to 2021. In the case of occupant sex, the findings agree with those of many recent investigations that have attempted to quantify the circumstances in which females show elevated rates of injury relative to their male counterparts given the same level bodily insult. This study, like others, provides evidence of certain female-specific injuries. The most problematic of these are AIS 2+ and AIS 3+ upper-extremity and lower-extremity injuries. These are among the most frequently observed injuries for females, and their incidence is consistently greater than for males. Overall, the odds of females sustaining MAIS 3+ (or fatality) are 4.5% higher than the odds for males, while the odds of females sustaining MAIS 2+ (or fatality) are 33.9% higher than those for males. The analyses highlight the need to carefully control for both the vehicle occupied, and the other involved vehicle, when calculating risk ratios by occupant sex. Female driver preferences in terms of vehicle class/size differ significantly from those of males, with females favoring smaller, lighter vehicles.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"14-33"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140859280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Frontal-Crash Occupant Protection in the Rear Seat: Submarining and Abdomen/Pelvis Response in Midsized Male Surrogates.","authors":"Allison J Guettler, Samuel T Bianco, Devon L Albert, David M Boyle, Andrew R Kemper, Warren N Hardy","doi":"10.4271/2023-22-0005","DOIUrl":"10.4271/2023-22-0005","url":null,"abstract":"<p><p>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 Hybrid III never underwent submarining while the THOR-50M submarined in three out of four vehicles. Submarining occurred in vehicles having both conventional and advanced (pretensioner and load limiter) restraints. The dominant factors associated with submarining were related to seat pan geometry. While the THOR-50M was not always an accurate tool for predicting submarining in the PMHS, the Hybrid III could not predict submarining at all. The results of this study identify substantive gaps in frontal-crash occupant protection in the rear seat for midsized males and elucidates the need for additional research for rear-seat occupant protection for all occupants.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"112-170"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140855817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Adult Female and Male PMHS Pelvis and Lumbar Response to Underbody Blast.","authors":"Hollie Pietsch, Danielle Cristino, Kerry Danelson, John Bolte, Matthew Mason, Andrew Kemper, John Cavanaugh, Warren Hardy","doi":"10.4271/2023-22-0003","DOIUrl":"10.4271/2023-22-0003","url":null,"abstract":"<p><p>The goal of this study was to gather and compare kinematic response and injury data on both female and male whole-body Post-mortem Human Surrogates (PMHS) responses to Underbody Blast (UBB) loading. Midsized males (50th percentile, MM) have historically been most used in biomechanical testing and were the focus of the Warrior Injury Assessment Manikin (WIAMan) program, thus this population subgroup was selected to be the baseline for female comparison. Both small female (5th percentile, SF) and large female (75th percentile, LF) PMHS were included in the test series to attempt to discern whether differences between male and female responses were predominantly driven by sex or size. Eleven tests, using 20 whole-body PMHS, were conducted by the research team. Preparation of the rig and execution of the tests took place at the Aberdeen Proving Grounds (APG) in Aberdeen, MD. Two PMHS were used in each test. The Accelerative Loading Fixture (ALF) version 2, located at APG's Bear Point range was used for all male and female whole-body tests in this series. The ALF was an outdoor test rig that was driven by a buried explosive charge, to accelerate a platform holding two symmetrically mounted seats. The platform was designed as a large, rigid frame with a deformable center section that could be tuned to simulate the floor deformation of a vehicle during a UBB event. PMHS were restrained with a 5-point harness, common in military vehicle seats. Six-degree-of-freedom motion blocks were fixed to L3, the sacrum, and the left and right iliac wings. A three-degree-of freedom block was fixed to T12. Strain gages were placed on L4 and multiple locations on the pelvis. Accelerometers on the floor and seat of the ALF provided input data for each PMHS' feet and pelvis. Time histories and mean peak responses in z-axis acceleration were similar among the three PMHS groups in this body region. Injury outcomes were different and seemed to be influenced by both sex and size contributions. Small females incurred pelvis injuries in absence of lumbar injures. Midsized males had lumbar vertebral body fractures without pelvis injuries. And large females with injuries had both pelvis and lumbar VB fractures. This study provides evidence supporting the need for female biomechanical testing to generate female response and injury thresholds. Without the inclusion of female PMHS, the differences in the injury patterns between the small female and midsized male groups would not have been recognized. Standard scaling methods assume equivalent injury patterns between the experimental and scaled data. In this study, small female damage occurred in a different anatomical structure than for the midsized males. This is an important discovery for the development of anthropomorphic test devices, injury criteria, and injury mitigating technologies. The clear separation of small female damage results, in combination with seat speeds, suggest that the small female pelvis injury thresho","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"44-77"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140851812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine-Learning-Accelerated Simulations for the Design of Airbag Constrained by Obstacles at Rest.","authors":"José E Valenzuela Del Río, Richard Lancashire, Karan Chatrath, Peter Ritmeijer, Elena Arvanitis, Lucia Mirabella","doi":"10.4271/2023-22-0001","DOIUrl":"10.4271/2023-22-0001","url":null,"abstract":"<p><p>Predicting airbag deployment geometries is an important task for airbag and vehicle designers to meet safety standards based on biomechanical injury risk functions. This prediction is also an extraordinarily complex problem given the number of disciplines and their interactions. State-of-the-art airbag deployment geometry simulations (including time history) entail large, computationally expensive numerical methods such as finite element analysis (FEA) and computational fluid dynamics (CFD), among others. This complexity results in exceptionally large simulation times, making thorough exploration of the design space prohibitive. This paper proposes new parametric simulation models which drastically accelerate airbag deployment geometry predictions while maintaining the accuracy of the airbag deployment geometry at reasonable levels; these models, called herein machine learning (ML)-accelerated models, blend physical system modes with data-driven techniques to accomplish fast predictions within a design space defined by airbag and impactor parameters. These ML-accelerated models are evaluated with virtual test cases of increasing complexity: from airbag deployments against a locked deformable obstacle to airbag deployments against free rigid obstacles; the dimension of the tested design spaces is up to six variables. ML training times are documented for completeness; thus, airbag design explorers or optimization engineers can assess the full budget for ML-accelerated approaches including training. In these test cases, the ML-accelerated simulation models run three orders of magnitude faster than the high-fidelity multi-physics methods, while accuracies are kept within reasonable levels within the design space.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140185767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Driving Behavior during Left-Turn Maneuvers at Intersections on Left-Hand Traffic Roads.","authors":"Yasuhiro Matsui, Masashi Narita, Shoko Oikawa","doi":"10.4271/2023-22-0007","DOIUrl":"10.4271/2023-22-0007","url":null,"abstract":"<p><p>Understanding left-turn vehicle-pedestrian accident mechanisms is critical for developing accident-prevention systems. This study aims to clarify the features of driver behavior focusing on drivers' gaze, vehicle speed, and time to collision (TTC) during left turns at intersections on left-hand traffic roads. Herein, experiments with a sedan and light-duty truck (< 7.5 tons GVW) are conducted under four conditions: no pedestrian dummy (No-P), near-side pedestrian dummy (Near-P), far-side pedestrian dummy (Far-P) and near-and-far side pedestrian dummies (NF-P). For NF-P, sedans have a significantly shorter gaze time for left-side mirrors compared with light-duty trucks. The light-duty truck's average speed at the initial line to the intersection (L1) and pedestrian crossing line (L0) is significantly lower than the sedan's under No-P, Near-P, and NF-P conditions, without any significant difference between any two conditions. The TTC for sedans is significantly shorter than that for trucks with near-side pedestrians (Near-P and NF-P) and far-side pedestrians in Far-P. These insights can contribute to the ongoing development of accident-prevention safety systems for left-turning maneuvers at intersections.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"180-201"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140862105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of DAMAGE Algorithm in Frontal Crashes.","authors":"Priya Prasad, Saeed D Barbat, Anil Kalra, Dainius J Dalmotas","doi":"10.4271/2023-22-0006","DOIUrl":"10.4271/2023-22-0006","url":null,"abstract":"<p><p>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 several test scenarios, the predicted risk of AIS2+ brain injuries are too high compared to real-world experience. The prediction of AIS4+ brain injury risk in lower velocity crashes is good, but too high in NCAP-like and high speed angular frontal crashes.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"67 ","pages":"171-179"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140860750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ligaments Laxity and Elongation at Injuryin Flexed knees during Lateral Impact Conditions.","authors":"Sahar Benadi,&nbsp;Xavier Trosseille,&nbsp;Philippe Petit,&nbsp;Jérôme Uriot,&nbsp;Yoann Lafon,&nbsp;Philippe Beillas","doi":"10.4271/2022-22-0003","DOIUrl":"10.4271/2022-22-0003","url":null,"abstract":"<p><p>The knee is one of the regions of interest for pedestrian safety assessment. Past testing to study knee ligament injuries for pedestrian impact only included knees in full extension and mostly focused on global responses. As the knee flexion angle and the initial ligament laxity may affect the elongation at which ligaments fail, the objectives of this study were (1) to design an experimental protocol to assess the laxity of knee ligaments before measuring their elongation at failure, (2) to apply it in paired knee tests at two flexion angles (10 and 45 degrees). The laxity tests combined strain gauges to measure bone strains near insertions that would result from ligament forces and a custom machine to exercise the knee in all directions. Failure was assessed using a four-point bending setup with additional degrees of freedom on the axial rotation and displacement of the femur. A template was designed to ensure that the two setups used the exact same starting position. The protocol was applied to six pairs of knees which were tested until the failure of all ligaments. In the laxity tests, a higher compliance of the knee was observed at 45 degrees compared to 10 degrees. Minimum lengths associated with the beginning of bone loading were also successfully identified for the collateral ligaments, but the process was less successful for the cruciate ligaments. The failure tests suggested increased elongation and length at failure for the ligaments and their bundles at 45°. This could be consistent with the higher compliance in static test, but the minimum lengths identified on the collaterals did not explain this difference during failure. The results highlight the possible relationship between position, laxity and elongation at failure in a lateral loading and provide a dataset including 3D coordinates of insertions to continue the investigation using a modelling approach. Perspectives are also outlined to improve upon the laxity determination protocol.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"66 ","pages":"69-97"},"PeriodicalIF":0.0,"publicationDate":"2022-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41111344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}