Stapp car crash journal最新文献

{"title":"Integration of Muscle Pre-tension and Activation to Evaluate Neck Muscle Strain Injury Risk during Simulated Rear Impacts Using a Finite Element Neck Model.","authors":"Matheus A Correia, Stewart D McLachlin, Duane S Cronin","doi":"10.4271/2025-22-0001","DOIUrl":"10.4271/2025-22-0001","url":null,"abstract":"<p><p>Prevention of rear-impact neck injuries remains challenging for safety designers due to a lack of understanding of the tissue-level response and injury risk. Soft tissue injuries have been inferred from clinical, cadaveric, and numerical studies; however, there is a paucity of data for neck muscle injury, commonly reported as muscle pain. The goal of this study was to investigate the effect of muscle pre-tension and activation on muscle strain and injury risk resulting from low-severity rear impacts using a detailed finite element head and neck model (HNM). The HNM was extracted from the GHBMC average stature male model and re-postured to match a volunteer study, with measured T1 kinematics applied as boundary conditions to the HNM. Three cases were simulated for three impact severities: the baseline repostured HNM, the HNM including muscle pre-tension, and the HNM with muscle pre-tension and muscle activation. The head kinematics, vertebral kinematics, muscle strains, and three neck injury criteria were calculated to assess injury risk. The kinematic response of the neck model demonstrated an S-shaped pattern, followed by extension in the rear impact cases. The maximum kinetics, kinematics, and muscle strains occurred later in the impact during the extension phase. The distribution and magnitude of muscle strain depended on muscle pre-tension and activation, and the largest predicted strains occurred at locations associated with muscle injury reported in the literature. The HNM with muscle pre-tension and muscle activation provides a tool to assess rear impact response and could inform injury mitigation strategies in the future.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"69 ","pages":"1-20"},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143410757","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 Injury Risk Functions of THOR-AV 50th Percentile Male Dummy.","authors":"Z Jerry Wang, George Hu","doi":"10.4271/2025-22-0004","DOIUrl":"https://doi.org/10.4271/2025-22-0004","url":null,"abstract":"<p><p>This research investigated injury risk functions (IRF) for the THOR-AV 50th percentile male dummy in accordance with ISO TS18506, focusing on areas with design changes. The IRF development utilized a combination of physical tests and finite element (FE) model simulations. For certain postmortem human subject test cases lacking physical dummy tests, the validated Humanetics THOR-AV FE model (v0.7.2) was used to quickly generate data, with the understanding that final IRFs based on full physical test data might offer greater accuracy. Log-logistic, log-normal, and Weibull survival functions were fitted with 95% confidence intervals. The Akaike Information Criterion, Goodman-Kruskal-Gamma, Area under the Curve of Receiver Operating Characteristic, and Quantile-Quantile plot were employed to assess the prediction strength and relative quality of the final IRF selections. Among the three survival distributions, the Weibull distribution provided the best fit. The lumbar Fz was identified as the best indicator for lumbar spine injury, followed by Lij. The Fz injury risk values at 5%, 25%, and 50% probabilities are 2170N, 3560N, and 4856N for MAIS2+, respectively. The Lij injury risk values at 5%, 25%, and 50% probabilities are 0.44, 0.65, and 0.79 for MAIS2+, respectively. Abdomen pressure from APTS sensors was found to be a weak indicator for abdomen injury prediction, with injury risk values at 5%, 25%, and 50% probabilities being 128, 209, and 268 kPa for MAIS2+, respectively. The total ASIS force from the left and right ASIS load cells was a better injury predictor than the maximum ASIS load from the individual load cells, with injury risk values at 5%, 25%, and 50% probabilities being 542, 1872, and 3522 Newtons for MAIS2+, respectively.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"69 1","pages":"82-113"},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144561281","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":"Proposed Reformulation of Brain Injury Criteria (BrIC) Using Head Rotation-Induced Brain Injury Thresholds Simulated and Derived Directly from A Subhuman Primate Finite Element Model.","authors":"Dominic R Demma, Ying Tao, Liying Zhang, Priya Prasad","doi":"10.4271/2025-22-0003","DOIUrl":"https://doi.org/10.4271/2025-22-0003","url":null,"abstract":"<p><p>Recent studies have found that Brain Injury Criteria (BrIC) grossly overpredicts instances of real-world, severe traumatic brain injury (TBI). However, as it stands, BrIC is the leading candidate for a rotational head kinematics-based brain injury criteria for use in automotive regulation and general safety standards. This study attempts to understand why BrIC overpredicts the likelihood of brain injury by presenting a comprehensive analysis of live primate head impact experiments conducted by Stalnaker et al. (1977) and the University of Pennsylvania before applying these injurious conditions to a finite element (FE) monkey model. Data collection included a thorough analysis and digitization of the head impact dynamics and resulting pathology reports from Stalnaker et al. (1977) as well as a representative reconstruction of the Penn II baboon diffuse axonal injury (DAI) model. Computational modeling techniques were employed on a FE Rhesus monkey model, first introduced by Arora et al. (2019), to derive risk related brain tissue strain thresholds from the laboratory data. The existing critical velocities proposed for BrIC were then scaled until the target strain level associated with each severity level of diffuse brain injury was reproduced in the FE model of the human brain. Overall, this study provides a comprehensive understanding of these two historical non-human primates (NHP) models and predicts a strain based diffuse tissue injury threshold (MPS99.9) of 1.0 and 1.6 for concussion (mild TBI) and DAI (severe TBI), respectively. The findings indicate scale factors of 1.6 to 5.9 times the original BrIC critical velocities, depending on the loading duration, are required to predict severe (AIS 4+) diffuse brain injury. These results allude to a necessity for including angular acceleration and duration as kinematic parameters in an injury criterion that can accurately predict real-world, diffuse brain injuries. This study also attempts to evaluate and recommend a methodology for post-processing strain parameters produced by head models, settling on the use of MPS99.9 and CSDM50.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"69 1","pages":"51-81"},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144561282","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":"Development of A Generic Nearside Impact Test Fixture for Evaluating In-Vehicle Crashworthiness of Wheelchairs.","authors":"Kyle Boyle, Jingwen Hu, Miriam Manary, Nichole R Orton, Kathleen D Klinich","doi":"10.4271/2025-22-0002","DOIUrl":"https://doi.org/10.4271/2025-22-0002","url":null,"abstract":"<p><p>Current voluntary standards for wheelchair crashworthiness only test under frontal and rear impact conditions. To help provide an equitable level of safety for occupants seated in wheelchairs under side impact, we developed a sled test procedure simulating nearside impact loading using a fixed staggered loading wall. Publicly available side impact crash data from vehicles that could be modified for wheelchair use were analyzed to specify a relevant crash pulse. Finite element modeling was used to approximate the side impact loading of a wheelchair during an FMVSS No. 214 due to vehicle intrusion. Validation sled tests were conducted using commercial manual and power wheelchairs and a surrogate wheelchair base fixture. Test procedures include methods to position the wheelchair to provide consistent loading for wheelchairs of different dimensions. The fixture and procedures can be used to evaluate the integrity of wheelchairs under side impact loading conditions.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"69 1","pages":"21-50"},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144561280","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":"Assessment of the skull fracture prediction capability of finite element head models.","authors":"Clément Pozzi, Marc Gardegaront, Lucille Allegre, Philippe Beillas","doi":"10.4271/2025-22-0005","DOIUrl":"https://doi.org/10.4271/2025-22-0005","url":null,"abstract":"<p><p>The development of drones has raised questions about their safety in case of high-speed impacts with the head. This has been recently studied with dummies, postmortem human surrogates and numerical models but questions are still open regarding the transfer of skull fracture tolerance and procedures from road safety to drone impacts. This study aimed to assess the performance of an existing head FE model (GHBMC M50-O v6.0) in terms of response and fracture prediction using a wide range of impact conditions from the literature (low and high-speed, rigid and deformable impactors, drones). The fracture prediction capability was assessed using 156 load cases, including 18 high speed tests and 19 tests for which subject specific models were built. The GHBMC model was found to overpredict peak forces, especially for rigid impactors and fracture cases. However, the model captured the head accelerations tendencies for drone impacts. The formulation of bone elements, the failure representation and the scalp material properties were found of interest for future investigation. The model still predicted a sizable proportion of skull fractures. With failure enabled, it reached a sensitivity of 86.6% and a specificity of 82.0% (n=156). With failure disabled, risk curves with a rating of good according to ISO/TS 18506:2014 were developed using the second principal strain in the outer table cortical solid elements.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"69 1","pages":"114-161"},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144561279","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":"Traumatic Head and Brain Injuries in Helmeted Motorcycle Crashes.","authors":"John Lloyd","doi":"10.4271/2025-22-0006","DOIUrl":"https://doi.org/10.4271/2025-22-0006","url":null,"abstract":"<p><p>This study presents an analysis of 364 motorcycle helmet impact tests, including standard certified full-face, open-face, and half-helmets, as well as non-certified (novelty) helmet designs. Two advanced motorcycle helmet designs that incorporate technologies intended to mitigate the risk of rotational brain injuries (rTBI) were included in this study. Results were compared to 80 unprotected tests using an instrumented 50th percentile Hybrid III head form and neck at impact speeds ranging from 6 to 18 m/s (13 to 40 mph). Results show that, on average, the Head Injury Criterion (HIC) was reduced by 92 percent across certified helmets, compared to the unhelmeted condition, indicating substantial protection against focal head and brain injuries. However, findings indicate that standard motorcycle helmets increase the risk of AIS 2 to 5 rotational brain injuries (rTBI) by an average of 30 percent compared to the unprotected condition, due to the increased rotational inertia generated by the added size and weight of the helmet. Advanced helmets performed, on average, about 5 percent better than standard certified helmets. Non-certified or novelty helmets offer inadequate protection against focal head and brain injuries, though they may offer some insight into rTBI protection. The findings of this study also indicate a critical methodological deficiency in the oblique impact tests utilized in revised motorcycle helmet standards, including ECE 22.06, Snell M2025, and FRHPe-02, which fail to correctly assess rTBI risk. This paper provides recommendations for enhancing motorcycle helmet design to improve protection against rotational traumatic brain injuries.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"69 1","pages":"162-180"},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144561283","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":"Effects of head restraint (HR) interference on child restraint system (CRS) performance in frontal and far-side impacts.","authors":"Julie A Mansfield","doi":"10.4271/2024-22-0003","DOIUrl":"10.4271/2024-22-0003","url":null,"abstract":"<p><p>Forward-facing child restraint systems (FF CRS) and high-back boosters often contact the vehicle seat head restraint (HR) when installed, creating a gap between the back surface of the CRS and the vehicle seat. The effects of HR interference on dynamic CRS performance are not well documented. The objective of this study is to quantify the effects of HR interference for FF CRS and high-back boosters in frontal and far-side impacts. Production vehicle seats with prominent, removeable HRs were attached to a sled buck. One FF CRS and two booster models were tested with the HR in place (causing interference) and with the HR removed (no interference). A variety of installation methods were examined for the FF CRS. A total of twenty-four tests were run. In frontal impacts, HR interference produced small but consistent increases in frontal head excursion and HIC36. Head excursions were more directly related to the more forward initial position rather than kinematic differences caused by HR interference. In far-side impacts, HR interference did not have consistent effects on injury metrics. Overall, these results suggest only slight benefits of removing the HR in frontal impacts specifically. Caregivers should use caution if removing a vehicle HR to ensure that the current child occupant and all future vehicle occupants have adequate head support available in case of a rear impact.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"68 ","pages":"31-56"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142547998","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":"Standardized Assessment of Gravity Settling Human Body Models for Virtual Testing.","authors":"B Wade von Kleeck Iii, Juliette Caffrey, Ashley A Weaver, F Scott Gayzik, Jason Hallman","doi":"10.4271/2024-22-0001","DOIUrl":"10.4271/2024-22-0001","url":null,"abstract":"<p><p>The increased use of computational human models in evaluation of safety systems demands greater attention to selected methods in coupling the model to its seated environment. This study assessed the THUMS v4.0.1 in an upright driver posture and a reclined occupant posture. Each posture was gravity settled into an NCAC vehicle model to assess model quality and HBM to seat coupling. HBM to seat contact friction and seat stiffness were varied across a range of potential inputs to evaluate over a range of potential inputs. Gravity settling was also performed with and without constraints on the pelvis to move towards the target H-Point. These combinations resulted in 18 simulations per posture, run for 800 ms. In addition, 5 crash pulse simulations (51.5 km/h delta V) were run to assess the effect of settling time on driver kinematics. HBM mesh quality and HBM to seat coupling metrics were compared at kinetically identical time points during the simulation to an end state where kinetic energy was near zero. A gravity settling time of 350 ms was found to be optimal for the upright driver posture and 290 ms for the reclined occupant posture. This suggests that reclined passengers can be settled for less time than upright passengers, potentially due to the increased contact area. The pelvis constrained approach was recommended for the upright driver posture and was not recommended for the reclined occupant posture. The recommended times were sufficient to gravity settle both postures to match the quality metrics of the 800 ms gravity settled time. Driver kinematics were found to be vary with gravity settling time. Future work will include verifying that these recommendations hold for different HBMs and test modes.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"68 ","pages":"1-13"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142297162","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 Bending Properties in Paired Human Ribs with and without Costal Cartilage.","authors":"Rose Schaffer, Yun-Seok Kang, Angelo Marcallini, Bengt Pipkorn, John H Bolte, Amanda M Agnew","doi":"10.4271/2024-22-0006","DOIUrl":"10.4271/2024-22-0006","url":null,"abstract":"<p><p>Thoracic injuries, most frequently rib fractures, commonly occur in motor vehicle crashes. With an increased reliance on human body models (HBMs) for injury prediction in various crash scenarios, all thoracic tissues and structures require more comprehensive evaluation for improvement of HBMs. The objective of this study was to quantify the contribution of costal cartilage to whole rib bending properties in physical experiments. Fifteen bilateral pairs of 5th human ribs were included in this study. One rib within each pair was tested without costal cartilage while the other rib was tested with costal cartilage. All ribs were subjected to simplified A-P loading at 2 m/s until failure to simulate a frontal thoracic impact. Results indicated a statistically significant difference in force, structural stiffness, and yield strain between ribs with and without costal cartilage. On average, ribs with costal cartilage experienced a lower force but greater displacement with a longer time to fracture compared to isolated ribs. Comparisons were complicated by varying levels of calcification between costal cartilages and varying geometry with the inclusion of the costal cartilage. This study highlights the important effects of costal cartilage on rib properties and suggests an increased focus on costal cartilage in HBMs in future work.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"68 ","pages":"104-154"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142865810","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 Child Anthropometries in Relation to Modern Vehicle Seat and Booster Dimensions.","authors":"Gretchen H Baker, Rosalie R Connell, Carrie A Rhodes, Julie A Mansfield","doi":"10.4271/2024-22-0004","DOIUrl":"10.4271/2024-22-0004","url":null,"abstract":"<p><p>This study compared modern vehicle and booster geometries with relevant child anthropometries. Vehicle geometries (seat length, seat pan height, shoulder belt outlet height, and roof height) were obtained for 275 center and outboard rear seating positions of US vehicles (MY 2009-2022). Measurements of 85 US boosters (pan height and pan length) and anthropometries of 80 US children between 4-14yo (seated height, thigh length, leg length, and seated shoulder height) were also collected. Comparisons were made between vehicles, boosters, and child anthropometries. Average vehicle seat lengths exceeded child thigh lengths (+9.5cm). Only 16.4% of seating positions had seat lengths less than the child thigh length mean+1SD. Even for children at least 145cm, only 18.8% had thigh lengths greater than the average vehicle seat length. Child thigh lengths were more comparable with average booster seat pan lengths for all multi-mode and high-back designs (-2.0cm) and low-back boosters (+3.1cm). The average observed booster pan height (9.9cm) would help most children achieve seated shoulder heights similar to the Hybrid III 5th percentile Female ATD. Compared to vehicle seats, booster geometries were more compatible with child thigh lengths and assist children in achieving seated shoulder heights more comparable to the vehicle restraint system. This emphasizes the continued need for shorter vehicle seat cushion lengths for these occupants and the need to educate caregivers and promote booster recommendations which highlight the importance of achieving proper belt fit and avoiding slouched postures, even for children greater than 8 years and/or 145cm.</p>","PeriodicalId":35289,"journal":{"name":"Stapp car crash journal","volume":"68 ","pages":"57-88"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142629801","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}