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The Hybrid-III Rail Safety (H3-RS) anthropomorphic test device (ATD), also known as a crash test dummy, was developed by the Rail Safety and Standards Board (RSSB), DeltaRail (now Resonate Group Ltd.), and the Transport Research Laboratory (TRL) in the United Kingdom between 2002 and 2005 for passenger rail safety applications [1]. The H3-RS is a modification of the standard Hybrid-III 50th percentile male (H3-50M) ATD with additional features in the chest and abdomen to increase its biofidelity and eight sensors to measure deflection. The H3-RS features bilateral (left and right) deflection sensors in the upper and lower chest and in the upper and lower abdomen; whereas, the standard H3-50M only features a single unilateral (center) deflection sensor in the chest with no deflection sensors located in the abdomen. Additional H3-RS research was performed by the Volpe National Transportation Systems Center (Volpe Center) under the direction of the U.S. Department of Transportation, Federal Railroad Administration (FRA) Office of Research, Development, and Technology. The Volpe Center contracted with TRL to conduct a series of dynamic pendulum impact tests [2]. The goal of testing the abdomen response of the H3-RS ATD was to develop data to refine an abdomen design that produces biofidelic and repeatable results under various impact conditions with respect to impactor geometry, vertical impact height, and velocity. In this study, the abdominal response of the H3-RS finite element (FE) model that TRL developed is validated using the results from pendulum impact tests [2]. Results from the pendulum impact tests and corresponding H3-RS FE simulations are compared using the longitudinal relative deflection measurements from the internal sensors in the chest and abdomen as well as the longitudinal accelerometer readings from the impactor. The abdominal response of the H3-RS FE model correlated well with the physical ATD as the impactor geometry, vertical impact height, and velocity were changed. There were limitations with lumbar positioning of the H3-RS FE model as well as the material definition for the relaxation rate of the foam in the abdomen that can be improved in future work. The main goal of validating the abdominal response of the dummy model is to enable its use in assessing injury potential in dynamic sled testing of crashworthy workstation tables, the results of which are presented in a companion paper [3]. The authors used the model of the H3-RS ATD to study the 8G sled test specified in the American Public Transportation Association (APTA) workstation table safety standard [4]. The 8G sled test is intended to simulate the longitudinal crash accleration in a severe train-to-train collision involving U.S. passenger equipment. Analyses of the dynamic sled test are useful for studying the sensitivity of the sled test to factors such as table height, table force-crush behavior, seat pitch, etc., which help to inform discussions on revisions to the test requirements eventually leading to safer seating environments for passengers.

Fixed workstation tables in passenger rail coaches can pose a potential injury hazard for passengers seated at them during an accident. Tables designed to absorb impact energy while minimizing contact forces can reduce the risk of serious injury, while helping to compartmentalize occupants during a train collision. The Rail Safety and Standards Board (RSSB) in the U.K. issued safety requirement GM/RT2100, Issue 5 [1] and the American Public Transportation Association (APTA) in the U.S. issued safety standard APTA PR-CS-S-018-13, Rev. 1 [2] with the goals of setting design and performance requirements for energy-absorbing workstation tables. The U.S. Department of Transportation, Federal Railroad Administration (FRA) Office of Research, Development and Technology directed the Volpe National Transportation Systems Center (Volpe Center) to evaluate the performance of the Hybrid-III Rail Safety (H3-RS) anthropomorphic test device (ATD), also known as a test dummy, in the APTA sled test in order to incorporate a reference to the H3-RS in the safety standard. The Volpe Center contracted with the manufacturer of the H3-RS, Transport Research Laboratory (TRL), in the U.K. to conduct a series of sled tests [3] with energy-absorbing tables, donated by various table manufacturers. The tables were either already compliant with the RSSB table standard or were being developed to comply with the APTA table standard. The sled test specified in Option A of the APTA table standard involves the use of two different 50th percentile male frontal impact ATDs. The H3-RS and the standard Hybrid-III (H3-50M) ATDs performed as expected. The H3-RS, which features bilateral deflection sensors in the chest and abdomen, was able to measure abdomen deflections while the H3-50M, which features a single sensor measuring chest compression, was not equipped to measure abdomen deflection. This study attempts to validate a finite element (FE) model of the APTA 8G sled test with respect to the thorax response of the H3-RS and H3-50M. The model uses a simplified rigid body-spring representation of one of the energy absorbing tables tested by TRL. The FE models of the H3-RS ATD and the H3-50M ATD were provided by TRL and LSTC, respectively. Results from the sled tests and FE simulations are compared using data obtained from the chest accelerometer, the chest and abdomen deflection sensors, and the femur load cells. Using video analysis, the gross motion of the dummies and table are also compared. Technical challenges related to model validation of the 8G sled test are also discussed. This study builds on previous analyses conducted to validate the abdomen response of the H3-RS FE model, which are presented in a companion paper [4].

Objective: Within the EC Seventh Framework project THORAX, the Mod-Kit THOR was upgraded with a new thorax and shoulder. The aim of this study was to investigate whether the THOR ATD met a set of prerequisites to a greater extent than Hybrid III and by that measure whether the dummy could serve as a potential tool for future evaluation of serious head and chest injuries in near-side oblique frontal impacts.Method: A small-overlap/oblique sled system was used to reflect occupant forces observed in oblique frontal crashes. The head and thoracic response from THOR was evaluated for 3 combinations: belt only with no deformation of the driver's side door (configuration A), belt only in combination with a predeformed door (configuration B), and prepretensioning belt and driver airbag (PPT+DAB) in combination with a predeformed door (configuration C). To evaluate head injury risk, the head injury criterion (HIC) and brain injury criteria (BrIC) were used. For evaluation of the thoracic injury risk, 3 injury criteria proposed by the THORAX project were evaluated: Dmax, DcTHOR, and strain (dummy rib fractures).Results: Unlike Hybrid III, the THOR with SD3 shoulder interacted with the side structure in a near-side oblique frontal impact. HIC values for the 3 test configurations corresponded to a 90% (A) and 100% (B and C) risk of Abbreviated Injury Scale (AIS) 2+ head injury, and BrIC values resulted in a 100% risk of AIS 2+ head injury in configurations A and B. In C the risk was reduced to 75%. The AIS 2+ thoracic injury risks based on Dmax were similar (14–18%) for all tests. Based on DcTHOR, AIS 2+ injury risk increased from 29 to 53% as the predeformed door side was introduced (A to B), and the risk increased, to 64%, as a PPT+DAB was added (C). Considering the AIS 2+ injury risk based on strain, tests in A resulted in an average of 3 dummy rib fractures (17%). Introducing the predeformed door (B) increased the average of dummy fractures to 5 (39%), but in C the average number of dummy rib fractures decreased to 4 (28%).Conclusions: THOR with an SD3 shoulder should be the preferred ATD rather than the Hybrid III for evaluating head and thorax injuries in oblique frontal impacts. Thoracic interaction with the predeformed door was not well captured by the 3D IR-Traccs; hence, use of deflection as an injury predictor in oblique loading is insufficient for evaluating injury risk in this load case. However, injury risk evaluation may be performed using the strain measurements, which characterize loading from seat belt and airbag as well as the lateral contribution of the structural impact in the loading condition used in this study.

Thoracic injuries are one of the dominant causes of fatalities and severe injuries in car crashes today. The tools available today for studying these injuries are not up to par with the latest implementation of restraint systems and airbags. THORAX is a collaborative medium scale project under the Seventh Framework, Theme 7 Transport which focusses on reduction and prevention of thoracic injuries through: • Understanding the thoracic injury mechanisms • Implementation of this understanding in numerical computer models and • Implementation of an updated thorax design in a crash test dummy The models and dummy will enable the design and evaluation of advanced restraint systems for a wide variety (gender, age and size) of car occupants. The THORAX project started in February 2009. This paper presents results achieved during the first two years of the project including outcomes of accident surveys, human body modelling activities and hardware dummy developments.

Objectives The mechanisms of upper limb injuries in road traffic accidents have not been widely investigated or understood. The present study was designed to obtain more specific information on upper limb injuries sustained by front seat occupants involved in front- and side-impact collision car accidents. Its purpose was to identify injuries that are a priority for prevention and further research. Methods Hospital records, radiographs and, where appropriate, crash data were reviewed. Data were analyzed to identify the frequency and severity of upper limb injuries, the mechanism of injury and the impairment sustained, in accordance with the American Medical Association guide. The total financial costs for NHS management, as well as that relating to the upper limb injury, were calculated. Results Sixty-two cases were reviewed (34 males), with a mean (range) age of 44 years (18 years to 83 years). There were 20 clavicle fractures of which 18 were right sided, and often attributed to a ‘seat-belt effect’. There were also 17 wrist and 13 forearm fractures. The median (range) upper limb Abbreviated Injury Score was 2 (2 to 4) and the overall Injury Severity Score was in the range 1 to 50 (median 6). In terms of impairment, the upper extremity sensory deficit was in the range 0% to 9% and motor deficit 0% to 22.5%, giving up to 5% sensory and 13.5% motor ‘whole person impairment’. The mean treatment cost for upper limb management was £2200 compared to a mean total injury treatment cost of £11,000 per person. Discussion The present study has served to identify the range and subsequent costs (impairment and financial) of upper limb injuries in road traffic accidents. These data will be used by researchers to advance the design of current and future car crash dummies in the upper limb and to allow accurate finite element remodelling. These data may be used in support of legislative changes in the future.

Background No research establishing the effects of climbing helmet-mounted cameras on head injury biomechanics. Objective Establish the potential effects of climbing helmet-mounted cameras on the injury risks associated with falling object strikes and falls onto flat and angled surfaces. Methods Three experimental studies were developed via the adaptation of European helmet testing standards and regulations. Study 1 performed falling striker tests to the helmet, Study 2 performed linear headform drop tests onto a flat anvil and Study 3 performed oblique headform drop tests onto an anvil angled 15° from vertical. Three helmet categories (hard-shell, foam and hybrid) were impacted at three locations (vertex, front and side), using five camera mounting combinations and three control helmets. Data was collected for the forces, linear accelerations, rotational velocities and rotational accelerations experienced by the headform. Results All helmet and camera combinations investigated by this project complied with current legislative performance criteria, while no combination exceeded published injury thresholds. No increase in head injury risk was observed for the forces transferred to the head during falling object strikes or with the linear accelerations experienced during falls onto flat and angled surfaces. Finally, although greater rotational head velocities and accelerations were observed with falls onto flat and angled surfaces, no injury threshold was exceeded by any investigated helmet and camera combination. Conclusions All helmet and camera combinations investigated by this project complied with current legislative performance criteria, while no combination exceeded published injury thresholds. Further research may be required to establish the effects of additional impact mechanism, helmet or camera mounting configurations.

Thoracic injuries are one of the main causes of fatalities and severe injuries in car crashes. The tools available today for studying these injuries are not up to par with the latest implementation of restraint systems and airbags. THORAX-FP7 is a collaborative medium scale project under the Seventh Framework. It focuses on the reduction and prevention of thoracic injuries through an improved understanding of the thoracic injury mechanisms and the implementation of this understanding in an updated design for the thorax-shoulder complex of the THOR dummy. The updated dummy should enable the design and evaluation of advanced restraint systems for a wide variety (gender, age and size) of car occupants. The hardware development involves fi ve steps: 1) Identifi cation of the dominant thoracic injury types from fi eld data, 2) Specifi cation of biomechanical requirements, 3) Identification of injury parameters and necessary instrumentation, 4) Dummy hardware development and 5) Evaluation of the demonstrator dummy. The THORAX project started in February 2009. This paper presents results achieved so far including outcomes of accident surveys, selection of human response data suitable for the assessment of the dummy performance, human body simulation into the injury criteria and the dummy developments done so far.

Bone mechanical properties are typically evaluated at relatively low strain rates. However, the strain rate related to traumatic failure is likely to be orders of magnitude higher and this higher strain rate is likely to affect the mechanical properties. Previous work reporting on the effect of strain rate on the mechanical properties of bone predominantly used nonhuman bone. In the work reported here, the effect of strain rate on the tensile and compressive properties of human bone was investigated. Human femoral cortical bone was tested longitudinally at strain rates ranging between 0.14–29.1s−1 in compression and 0.08–17 s−1 in tension. Young’s modulus generally increased, across this strain rate range, for both tension and compression. Strength and strain (at maximum load) increased slightly in compression and decreased (for strain rates beyond 1 s−1) in tension. Stress and strain at yield decreased (for strain rates beyond 1 s−1) for both tension and compression. In general, there seemed to be a relatively simple linear relationship between yield properties and strain rate, but the relationships between postyield properties and strain rate were more complicated and indicated that strain rate has a stronger effect on postyield deformation than on initiation of yielding. The behavior seen in compression is broadly in agreement with past literature, while the behavior observed in tension may be explained by a ductile to brittle transition of bone at moderate to high strain rates.

International audience

The WorldSID program was set up to develop a new, worldwide acceptable, advanced technology, side impact crash test dummy for improved assessment of injury risk to car occupants in lateral collisions. Following the release of the mid-sized male WorldSID, the development of the small female WorldSID dummy was initiated by the EC 6th Framework collaborative research project "APROSYS"; in 2004. The main specifications and requirements of the new dummy have been defined in terms of anthropometry, biomechanical response and instrumentation capabilities in general and per body segment. An overview of the specification is given in this paper. Two prototype dummies have been evaluated against a first set of test conditions. Test results are presented here, including pendulum impactor, linearly guided impactor, drop and sled tests. For a prioritised matrix of biomechanical test conditions, the dummy responses were compared against the biomechanical human response requirements. Furthermore, the dummy's repeatability in well-controlled test conditions and its sensitivity to temperature were studied and its compliance to anthropometric requirements is reported. Following the assessment of the dummy's current biofidelity and maturity, recommendations for further dummy improvements are given in the conclusions.

International audience

International audience

International audience

47th Stapp Car Crash Journal, , , -; Six European laboratories have evaluated the biomechanical response of the new advanced frontal impact dummy THOR-alpha with respect to the European impact response requirements. Me results indicated that for many of the body regions (e.g. shoulder, spine, thorax, femur/knee) the THOR-alpha response was close to the human response and more biofidelic than die Hybrid111. In addition, the durability, repeatability and sensitivity for some dummy regions have been evaluated. Based on the tests performed, it was found that the THOR-alpha is less durable than the Hybrid-III. The Jack in durability of the THOR-alpha caused a problem in completing the full test program and in evaluating the repeatability of the dummy. Results have demonstrated that the assessment of frontal impact protection can be greatly improved with a more advanced frontal impact dummy. Regarding biofidelity and injury assessment capabilities, 'the THOR-alpha is a good candidate however it needs to be brought up to standard in other areas. Based on the results obtained recommendations were defined for the improvement of the THOR-alpha dummy. Mots clés libres :performance, biofidelity, thor-alpha, HYBRID-III.