副级吸能机构对客车-轿车正面碰撞影响的分析

为解决客车与轿车在纵梁高度吸能位置正面碰撞不兼容的问题,设计一种客车前部副级吸能机构。利用三维显式有限元分析软件LS-DYNA 3D,建立轿车Taurus和中型客车6900Y面对面100%重叠碰撞下的数值仿真模型。研究副级吸能机构对解决汽车前部吸能高度不兼容问题的影响,对比分析2车正面碰撞过程中轿车方向盘侵入量、侵入速度和客车车门变形量、乘员头部位置加速度。结果表明:未装副级吸能机构时,轿车方向盘侵入速度和Z方向侵入量较大,容易发生钻碰现象;客车前部副级吸能机构能降低轿车方向盘的侵入量和侵入速度,同时能减小客车驾驶室车门变形量,降低乘员头部位置加速度。     

偏置碰撞中轿车左后排乘员损伤的研究

为识别轿车正面偏置碰撞中后排左侧乘员的损伤特点,开展模拟研究。利用HyperMesh有限元软件,建立包含有限元轿车、可变形壁障及假人的基础模型1,并在基础模型1上为假人添加三点式安全带,建立模型2,在模型2基础上为假人创建侧气囊,建立模型3;采用Ls-Dyna软件求解计算,并应用HyperGraph软件分析不同重叠率偏置碰撞下假人的损伤情况;对比基础模型1、模型2、模型3仿真试验的假人损伤情况,分析不同约束系统对左后排假人的保护效能。结果表明:随着碰撞重叠率增大,左后排乘员头部和胸部的加速度峰值均相应减小;碰撞重叠率在试验范围内变化时,颈部所受合力的峰值波动较小;使用安全带能显著降低乘员的损伤;侧气囊对乘员胸部有保护作用。     

轿车斜角碰撞后排左侧乘员损伤仿真研究

为降低后排左侧乘员在轿车60°斜角碰撞刚性壁障时的损伤程度,利用Presys建立有限元轿车、刚性障碍壁和假人整体模型,经Ls-Dyna求解计算后用Presys有限元软件分析30、40、50 km/h车速下的后排左侧乘员损伤情况。结果表明:随着碰撞车速的增高后排左侧假人头部加速度和颈部受力增大;碰撞车速为40 km/h时假人头部Y轴加速度比其他2种碰撞车速大;假人胸部加速度及加速度增幅随着碰撞车速的增加而增大。     

带乘员及约束系统汽车正面碰撞的有限元法仿真研究

采用计算机模拟的方法,对国产某轿车发生正面碰撞时,乘员在佩带三点式安全带的约束状态下的运动响应进行研究,从乘员的运动响应情况、乘员舱的变形情况、假人的HIC值等几个方面分析了该车型的乘员保护安全性能.模拟结果表明,该车达到了安全法规的要求.并探讨了运用有限元法对带乘员及约束系统的整车正面碰撞的计算机模拟方法.     

正面碰撞事故中大客车乘员损伤影响因素分析

为研究乘客在大客车正面碰撞事故中的损伤机理，建立某全承载大客车有限元模型，并通过试验验证有限元模型的仿真精度。基于验证模型对不同碰撞速度条件下大客车车身结构力学响应、生存空间、座椅固定件强度、乘员运动响应和损伤等进行综合分析及评价。结果表明:高速碰撞条件下，驾驶员生存空间容易被侵入，座椅固定件强度存在失效的风险；乘员头部、颈部和胸部的损伤值受碰撞速度、安全带类型和乘员位置影响较大；三点式安全带保护效果明显优于两点式安全带。     

基于车-车碰撞仿真的驾乘人员损伤差异影响因素

为了解车-车碰撞事故中驾乘人员损伤差异影响因素,首先运用PC-Crash软件再现一例真实交通事故,通过分析面包车驾驶员的运动学及损伤响应,验证了其仿真车内乘员损伤的有效性,然后设计了包含6组车速、12个碰撞位置的72次试验,并通过仿真获得人体损伤数据,利用作图法分析所得数据.结果表明:当且仅当车速大于等于50 km/h时,驾乘人员头、胸、腿等部位的损伤才会出现明显差异,且差异程度随碰撞车速增加而增大;当车速大于50 km/h且碰撞位置在被撞车辆左侧或右侧前方时,驾乘人员各部位损伤差异最明显,其中又以腿部损伤最为突出,且靠近撞击侧乘员的损伤更严重.研究成果将为更好地利用损伤认定驾乘关系提供支持.     

大客车正面碰撞乘客约束系统仿真分析

为探究约束系统在全承载客车正面碰撞事故中对乘客损伤的影响,利用有限元分析软件LSDYNA建立某大客车正面碰撞仿真模型,并开展整车50 km/h正面100%重叠碰撞固定刚性壁障试验;从车身变形、加速度曲线和乘员损伤等3方面验证仿真模型;基于已验证的仿真模型,开展不同座椅间距、车厢位置及安全带类型的乘员运动响应和损伤等综合分析与评价。研究结果表明:不同位置车身加速度波形整体趋势相似,但具体峰值和出现时刻存在差异;增大座椅间距和主动预紧安全带能够有效降低降低头部损伤值,而颈部损伤则随之增大;乘客胸部损伤值和大腿力受主动预紧安全带、座椅间距和车厢位置影响不大。     

汽车后排座椅侧气囊仿真系统参数优化研究

为提升侧面碰撞中后排乘员胸腹部保护效果,在国内某款汽车原有侧面碰撞系统模型基础上,构建后排座椅侧气囊(RSAB)仿真试验模型,通过各项零部件试验与气囊模型对标后导入侧面碰撞系统试验模型;分析RSAB及气帘对后排被试的保护性能,针对胸腹部损伤防护优化侧面气囊相关参数,设计正交试验,运用极差分析法,得出最优参数组合,并对比优化前后结果与实车试验数据,验证优化方案的有效性与可行性。研究结果表明:通过选取关键参数,结合正交试验设计和极差分析法,对胸部气囊的泄气孔直径、位置以及点火时刻进行参数匹配优化,得到座椅侧气囊防护最优参数组合为泄气孔位置在上方、点火时刻为5 ms、泄气孔直径为25 mm,胸腹部压缩量可分别降低21.29%和18.93%。     

车对车侧面碰撞兼容性影响因素分析

汽车碰撞兼容性由于能更好地反映真实交通事故,已发展成为被动安全研究领域中最具安全技术潜力的新技术。针对侧面冲击载荷作用下车对车的碰撞兼容性问题,从理论分析和仿真分析角度出发,研究了主要影响因素:两车质量比、汽车前端刚度特性、汽车几何特征对两车碰撞兼容性的影响。结果表明:质量比是影响两车兼容性好坏的关键因素,通过降低汽车前端变形吸能刚度和主吸能位置、提高两车碰撞接触面积等可以提高被撞击车的耐撞性和降低撞击车的攻击性,从而降低所有涉案人员损伤,提高车对车侧面碰撞兼容性。     

大客车侧翻过程中约束系统对乘客安全影响*

为研究约束系统对客车侧翻过程中乘客安全的影响，在经过试验验证的某客车侧翻碰撞有限元模型上截取部分车身截段，建立“车身截段-约束系统-乘员”侧翻仿真模型，开展不同约束条件下乘员运动响应和损伤的综合分析及评价。结果表明:满足《客车上部结构强度要求及试验方法》（GB 17578—2013）法规要求的客车在侧翻过程中仍然可能对乘员造成较严重的头部损伤风险；主动预紧安全带能够在侧翻碰撞过程中，有效缓解乘员的头部和颈部损伤程度；胸部损伤值受不同约束系统影响较小。     

Injuries in Full-Scale Vehicle Side Impact Moving Deformable Barrier and Pole Tests Using Postmortem Human Subjects

Objective: To conduct near-side moving deformable barrier (MDB) and pole tests with postmortem human subjects (PMHS) in full-scale modern vehicles, document and score injuries, and examine the potential for angled chest loading in these tests to serve as a data set for dummy biofidelity evaluations and computational modeling.

Methods: Two PMHS (outboard left front and rear seat occupants) for MDB and one PMHS (outboard left front seat occupant) for pole tests were used. Both tests used sedan-type vehicles from same manufacturer with side airbags. Pretest x-ray and computed tomography (CT) images were obtained. Three-point belt-restrained surrogates were positioned in respective outboard seats. Accelerometers were secured to T1, T6, and T12 spines; sternum and pelvis; seat tracks; floor; center of gravity; and MDB. Load cells were used on the pole. Biomechanical data were gathered at 20 kHz. Outboard and inboard high-speed cameras were used for kinematics. X-rays and CT images were taken and autopsy was done following the test. The Abbreviated Injury Scale (AIS) 2005 scoring scheme was used to score injuries.

Results: MDB test: male (front seat) and female (rear seat) PMHS occupant demographics: 52 and 57 years, 177 and 166 cm stature, 78 and 65 kg total body mass. Demographics of the PMHS occupant in the pole test: male, 26 years, 179 cm stature, and 84 kg total body mass. Front seat PMHS in MDB test: 6 near-side rib fractures (AIS = 3): 160–265 mm vertically from suprasternal notch and 40–80 mm circumferentially from center of sternum. Left rear seat PMHS responded with multiple bilateral rib fractures: 9 on the near side and 5 on the contralateral side (AIS = 3). One rib fractured twice. On the near and contralateral sides, fractures were 30–210 and 20–105 mm vertically from the suprasternal notch and 90–200 and 55–135 mm circumferentially from the center of sternum. A fracture of the left intertrochanteric crest occurred (AIS = 3). Pole test PMHS had one near-side third rib fracture. Thoracic accelerations of the 2 occupants were different in the MDB test. Though both occupants sustained positive and negative x-accelerations to the sternum, peak magnitudes and relative changes were greater for the rear than the front seat occupant. Magnitudes of the thoracic and sternum accelerations were lower in the pole test.

Conclusions: This is the first study to use PMHS occupants in MDB and pole tests in the same recent model year vehicles with side airbag and head curtain restraints. Injuries to the unilateral thorax for the front seat PMHS in contrast to the bilateral thorax and hip for the rear seat occupant in the MDB test indicate the effects of impact on the seating location and restraint system. Posterolateral locations of fractures to the front seat PMHS are attributed to constrained kinematics of occupant interaction with torso side airbag restraint system. Angled loading to the rear seat occupant from coupled sagittal and coronal accelerations of the sternum representing anterior thorax loading contributed to bilateral fractures. Inward bending initiated by the distal femur complex resulting in adduction of ipsilateral lower extremity resulted in intertrochanteric fracture to the rear seat occupant. These results serve as a data set for evaluating the biofidelity of the WorldSID and federalized side impact dummies and assist in validating human body computational models, which are increasingly used in crashworthiness studies.     

Potential of a Precrash Lateral Occupant Movement in Side Collisions of (Electric) Minicars

Objective: In minicars, the survival space between the side structure and occupant is smaller than in conventional cars. This is an issue in side collisions. Therefore, in this article a solution is studied in which a lateral seat movement is imposed in the precrash phase. It generates a pre-acceleration and an initial velocity of the occupant, thus reducing the loads due to the side impact.

Methods: The assessment of the potential is done by numerical simulations and a full-vehicle crash test. The optimal parameters of the restraint system including the precrash movement, time-to-fire of head and side airbag, etc., are found using metamodel-based optimization methods by minimizing occupant loads according to European New Car Assessment Programme (Euro NCAP).

Results: The metamodel-based optimization approach is able to tune the restraint system parameters. The numerical simulations show a significant averaged reduction of 22.3% in occupant loads.

Conclusion: The results show that the lateral precrash occupant movement offers better occupant protection in side collisions.     

Repeatability of a dynamic rollover test system

Objective: The goal of this study was to characterize the rollover crash and to evaluate the repeatability of the Dynamic Rollover Test System (DRoTS) in terms of initial roof-to-ground contact conditions, vehicle kinematics, road reaction forces, and vehicle deformation.

Methods: Four rollover crash tests were performed on 2 pairs of replicate vehicles (2 sedan tests and 2 compact multipurpose van [MPV] tests), instrumented with a custom inertial measurement unit to measure vehicle and global kinematics and string potentiometers to measure pillar deformation time histories. The road was instrumented with load cells to measure reaction loads and an optical encoder to measure road velocity. Laser scans of pre- and posttest vehicles were taken to provide detailed deformation maps.

Results: Initial conditions were found to be repeatable, with the largest difference seen in drop height of 20 mm; roll rate, roll angle, pitch angle, road velocity, drop velocity, mass, and moment of inertia were all 7% different or less. Vehicle kinematics (roll rate, road speed, roll and pitch angle, global Z′ acceleration, and global Z′ velocity) were similar throughout the impact; however, differences were seen in the sedan tests because of a vehicle fixation problem and differences were seen in the MPV tests due to an increase in reaction forces during leading side impact likely caused by disparities in roll angle (3° difference) and mass properties (2.2% in moment of inertia [MOI], 53.5 mm difference in center of gravity [CG] location).

Conclusions: Despite those issues, kinetic and deformation measures showed a high degree of repeatability, which is necessary for assessing injury risk in rollover because roof strength positively correlates with injury risk (Brumbelow 2009). Improvements of the test equipment and matching mass properties will ensure highly repeatable initial conditions, vehicle kinematics, kinetics, and deformations.     

Constrained Laboratory vs. Unconstrained Steering-Induced Rollover Crash Tests

Objective: The goal of this study was to evaluate how well an in-laboratory rollover crash test methodology that constrains vehicle motion can reproduce the dynamics of unconstrained full-scale steering-induced rollover crash tests in sand.

Methods: Data from previously-published unconstrained steering-induced rollover crash tests using a full-size pickup and mid-sized sedan were analyzed to determine vehicle-to-ground impact conditions and kinematic response of the vehicles throughout the tests. Then, a pair of replicate vehicles were prepared to match the inertial properties of the steering-induced test vehicles and configured to record dynamic roof structure deformations and kinematic response.

Results: Both vehicles experienced greater increases in roll-axis angular velocities in the unconstrained tests than in the constrained tests; however, the increases that occurred during the trailing side roof interaction were nearly identical between tests for both vehicles. Both vehicles experienced linear accelerations in the constrained tests that were similar to those in the unconstrained tests, but the pickup, in particular, had accelerations that were matched in magnitude, timing, and duration very closely between the two test types. Deformations in the truck test were higher in the constrained than the unconstrained, and deformations in the sedan were greater in the unconstrained than the constrained as a result of constraints of the test fixture, and differences in impact velocity for the trailing side.

Conclusions: The results of the current study suggest that in-laboratory rollover tests can be used to simulate the injury-causing portions of unconstrained rollover crashes. To date, such a demonstration has not yet been published in the open literature. This study did, however, show that road surface can affect vehicle response in a way that may not be able to be mimicked in the laboratory. Lastly, this study showed that configuring the in-laboratory tests to match the leading-side touchdown conditions could result in differences in the trailing side impact conditions.     

Association Between NCAP Ratings and Real-World Rear Seat Occupant Risk of Injury

Objective: Several studies have evaluated the correlation between U.S. or Euro New Car Assessment Program (NCAP) ratings and injury risk to front seat occupants, in particular driver injuries. Conversely, little is known about whether NCAP 5-star ratings predict real-world risk of injury to restrained rear seat occupants. The NHTSA has identified rear seat occupant protection as a specific area under consideration for improvements to its NCAP. In order to inform NHTSA's efforts, we examined how NCAP's current 5-star rating system predicts risk of moderate or greater injury among restrained rear seat occupants in real-world crashes.

Methods: We identified crash-involved vehicles, model year 2004–2013, in NASS-CDS (2003–2012) with known make and model and nonmissing occupant information. We manually matched these vehicles to their NCAP star ratings using data on make, model, model year, body type, and other identifying information. The resultant linked NASS-CDS and NCAP database was analyzed to examine associations between vehicle ratings and rear seat occupant injury risk; risk to front seat occupants was also estimated for comparison. Data were limited to restrained occupants and occupant injuries were defined as any injury with a maximum Abbreviated Injury Scale (AIS) score of 2 or greater.

Results: We linked 95% of vehicles in NASS-CDS to a specific vehicle in NCAP. The 18,218 vehicles represented an estimated 6 million vehicles with over 9 million occupants. Rear seat passengers accounted for 12.4% of restrained occupants. The risk of injury in all crashes for restrained rear seat occupants was lower in vehicles with a 5-star driver rating in frontal impact tests (1.4%) than with 4 or fewer stars (2.6%, P =.015); results were similar for the frontal impact passenger rating (1.3% vs. 2.4%, P =.024). Conversely, side impact driver and passenger crash tests were not associated with rear seat occupant injury risk (driver test: 1.7% for 5-star vs. 1.8% for 1–4 stars; passenger test: 1.6% for 5 stars vs 1.8% for 1–4 stars).

Conclusions: Current frontal impact test procedures provide some degree of discrimination in real-world rear seat injury risk among vehicles with 5 compared to fewer than 5 stars. However, there is no evidence that vehicles with a 5-star side impact passenger rating, which is the only crash test procedure to include an anthropomorphic test dummy (ATD) in the rear, demonstrate lower risks of injury in the rear than vehicles with fewer than 5 stars. These results support prioritizing modifications to the NCAP program that specifically evaluate rear seat injury risk to restrained occupants of all ages.     

Field investigation of child restraints in side impact crashes

OBJECTIVE: Various test procedures have been suggested for assessing the protection afforded by child restraints (CRS) in lateral collisions. Analyses of real world crashes can be used to identify relevant characteristics of the child, restraint, collision, and injury mechanisms that should be incorporated into the design of the test procedures as well as in the design of related ATDs and injury metrics. The objective of this work is to use in-depth crash investigations of children restrained in CRS in side impacts to elucidate specific sources and mechanisms of injuries and explore the role of crash severity variables such as magnitude and location of intrusion and specific impact angle. METHODS: Real world crashes involving children restrained in forward facing CRS in side impacts were analyzed from Partners for Child Passenger Safety, an on-going child specific crash surveillance system in which insurance claims are used to identify cases. In-depth crash investigations using standardized protocols were used to calculate the crash severity and determine the mechanisms and sources of the injuries sustained. RESULTS: Cases of 32 children restrained in CRS in 30 side impact crashes were examined. Twenty-five percent sustained AIS 2+ injuries. The most common injuries sustained by children restrained in CRS in side impact crashes were to the face, head, and lower extremity. Characteristics of the crashes that appeared related to injury were intrusion that entered the child's occupant space or caused an interior part of the vehicle to enter the child's occupant space, forward component of the crash, and the rotation of the CRS, restrained by a seat belt, towards the side of the impact. CONCLUSIONS: The ability to assess the injury potential in a laboratory setting for the body regions of common injury, the head, face, and lower extremity, must be explored. Characteristics of a regulatory-based test procedure to assess injury risk should include a frontal component to the crash and intrusion into the occupant's seating position. Design enhancements of the CRS should address rotation during lateral impacts. These results provide guidance to current efforts to design and regulate these restraints for the safety of child passengers in side impacts.     

A Multi-body Integrated Vehicle-Occupant Model for Compatibility Studies in Frontal Crashes

Vehicle acceleration and passenger compartment intrusion primarily determine car occupant injury risk. A new integrated vehicle-occupant model was developed and validated to predict these vehicle responses in offset, concentrated or full-width impact with various objects. The multi-body mathematical model consisted of a compartment, dash-panel and toepan-area and a front structure. The front structure was subdivided in 12 segments and a power-train, which were connected to the firewall by kinematic joints. The joints used local stiffness obtained from load-cell barrier crash-tests, and enabled local deformation of the vehicle front Similarly, the dash-panel and toepan were connected to the compartment, which enabled local intrusion into the compartment. A vehicle interior was modeled to enable contact-interactions with occupants, and the firewall geometry was included for interactions with the power-train.

The vehicle-model was validated with full frontal and 50% offset data and predicted vehicle acceleration, crush profile and local intrusion well. The validity of the model indicates its applicability in a wide range of frontal (non-distributed) collisions. Due to the use of local stiffness data, the model can greatly improve accident reconstruction research especially in frontal offset and pole impacts at both high and low speeds. The vehicle-model can be easily adjusted by changing vehicle-mass, size, or local stiffnesses of the front structure, and is a useful tool in compatibility research to estimate trends in car crash compatibility.     

Difference in dummy responses in matched side impact tests of vehicles with and without side airbags

Objective: Insurance Institute for Highway Safety (IIHS) high-hooded side impacts were analyzed for matched vehicle tests with and without side airbags. The comparison provides a measure of the effectiveness of side airbags in reducing biomechanical responses for near-side occupants struck by trucks, SUVs, and vans at 50 km/h.

Method: The IIHS moving deformable barrier (MDB) uses a high-hooded barrier face. It weighs 1,500 kg and impacts the driver side perpendicular to the vehicle at 50 km/h. SID IIs dummies are placed in the driver and left second-row seats. They represent fifth percentile female occupants.

IIHS tests were reviewed for matches with one test with a side airbag and another without it in 2003–2007 model year (MY) vehicles. Four side airbag systems were evaluated: (1) curtain and torso side airbags, (2) head and torso side airbag, (3) curtain side airbag, and (4) torso side airbag.

There were 24 matched IIHS vehicle tests: 13 with and without a curtain and torso side airbags, 4 with and without a head and torso side airbag, 5 with and without a side curtain airbag, and 2 with and without a torso airbag. The head, chest, and pelvis responses were compared for each match and the average difference was determined across all matches for a type of side airbag.

Results: The average reduction in head injury criterion (HIC) was 68 ± 16% (P < .001) with curtain and torso side airbags compared to the HIC without side airbags. The average HIC was 296 with curtain and torso side airbags and 1,199 without them. The viscous response (VC) was reduced 54 ± 19% (P < .005) with curtain and torso side airbags. The combined acetabulum and ilium force (7 ± 15%) and pelvic acceleration (?2 ± 17%) were essentially similar in the matched tests.

The head and torso side airbag reduced HIC by 42 ± 30% (P < .1) and VC by 32 ± 26% compared to vehicles without a side airbag. The average HIC was 397 with the side head and torso airbag compared to 729 without it. The curtain airbag and torso airbag only showed lower head responses but essentially no difference in the chest and pelvis responses.

Conclusion: The curtain and torso side airbags effectively reduced biomechanical responses for the head and chest in 50 km/h side impacts with a high-hooded deformable barrier. The reductions in the IIHS tests are directionally the same as estimated fatality reductions in field crashes reported by NHTSA for side airbags.     

The role of door orientation on occupant injury in a nearside impact: a CIREN, MADYMO modeling and experimental study

OBJECTIVE: This study addressed the effects of vehicle height mismatch in side impact crashes. A light truck or SUV tends to strike the door of a passenger car higher causing the upper border to lead into the occupant space. Conversely, an impact centered lower on the door, from a passenger car, causes the lower border to lead. We proposed the hypothesis that the type of injury sustained by the occupant could be related to door orientation during its intrusion into the passenger compartment. METHOD: Data on door orientation and nearside occupant injuries were collected from 125 side impact crashes reported in the CIREN database. Experimental testing was performed using a pendulum carrying a frame and a vehicle door, impacting against a USDOT SID. The frame allowed the door orientation to be changed. A model was developed in MADYMO (v 6.2) using the more biofidelic dummies, BIOSID, and SIDIIs as well as USDOT SID. RESULTS: In side impact crashes with the lower border of the door leading, 81% of occupants sustained pelvic injury, 42% suffered rib fractures, and the rate of organ injury was 0.84. With the upper border leading, 46% of occupants sustained pelvic injury, 71% sustained rib fracture, and the rate of organ injuries per case increased to 1.13. The differences in the groups with respect to pelvic injury were significant at p = 0.01, rib fracture, p = 0.10, and organ injury, p = 0.001. Experimental testing showed that when the door angle changed from lower to upper border leading, peak T4 acceleration increased by 273% and pelvic acceleration decreased by 44%. The model demonstrated that when the door angle changed from lower to upper border leading, the USDOT SID showed a 29% increase in T4 acceleration and a 57% decrease in pelvic acceleration. The BIOSID dummy demonstrated a 36% increase in T1 acceleration, a 44% increase in abdominal rib 1 deflection, a 91% increase in thoracic rib 1 deflection, and a 33% decrease in pelvic acceleration. CONCLUSIONS: These data add more insight to the problem of mismatch during side impacts, where the bumper of the striking vehicle overrides the door beam, causing the upper part of the door to lead the intrusion into the passenger compartment. Even with the same delta V and intrusion, with the upper border of the door leading, more severe chest and organ injuries resulted. This data suggests that door orientation should be considered when testing subsystems for side impact protection.     

Assessment of Bilateral Thoracic Loading on the Near-Side Occupant Due to Occupant-to-Occupant Interaction in Vehicle Crash Tests

Objective: This study aims, by means of the WorldSID 50th percentile male, to evaluate thoracic loading and injury risk to the near-side occupant due to occupant-to-occupant interaction in combination with loading from an intruding structure.

Method: Nine vehicle crash tests were performed with a 50th percentile WorldSID male dummy in the near-side (adjacent to the intruding structure) seat and a THOR or ES2 dummy in the far-side (opposite the intruding structure) seat. The near-side seated WorldSID was equipped with 6 + 6 IR-Traccs (LH and RH) in the thorax/abdomen enabling measurement of bilateral deflection. To differentiate deflection caused by the intrusion, and the deflection caused by the neighboring occupant, time history curves were analyzed. The crash tests were performed with different modern vehicles, equipped with thorax side airbags and inflatable curtains, ranging from a compact car to a large sedan, and in different loading conditions such as car-to-car, barrier, and pole tests. Lateral delta V based on vehicle tunnel acceleration and maximum residual intrusion at occupant position were used as a measurement of crash severity to compare injury measurements.

Result: In the 9 vehicle crash tests, thoracic loading, induced by the intruding structure as well as from the far-side occupant, varied due to the size and structural performance of the car as well as the severity of the crash. Peak deflection on the thoracic outboard side occurred during the first 50 ms of the event. Between 70 to 150 ms loading induced by the neighboring occupant occurred and resulted in an inboard-side peak deflection and viscous criterion. In the tests where the target vehicle lateral delta V was below 30 km/h and intrusion less than 200 mm, deflections were low on both the outboard (20–40 mm) and inboard side (10–15 mm). At higher crash severities, delta V 35 km/h and above as well as intrusions larger than 350 mm, the inboard deflections (caused by interaction to the far-side occupant) were of the same magnitude or even higher (30–70 mm) than the outboard deflections (30–50 mm).

Conclusion: A WorldSID 50th percentile male equipped with bilateral IR-Traccs can detect loading to the thorax from a neighboring occupant making injury risk assessment feasible for this type of loading. At crash severities resulting in a delta V above 35 km/h and intrusions larger than 350 mm, both the inboard deflection and VC resulted in high risks of Abbreviated Injury Scale (AIS) 3+ injury, especially for a senior occupant.