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Purpose: Head injury criterion (HIC) companied by a rotation-based metric was widely believed to be helpful for head injury prediction in road traffic accidents. Recently, the Euro-New Car Assessment Program utilized a newly developed metric called diffuse axonal multi-axis general evaluation (DAMAGE) to explain test device for human occupant restraint (THOR) head injury, which demonstrated excellent ability in capturing concussions and diffuse axonal injuries. However, there is still a lack of comprehensive understanding regarding the effectiveness of using DAMAGE for Hybrid Ⅲ 50th percentile male dummy (H50th) head injury assessment. The objective of this study is to determine whether the DAMAGE could capture the risk of H50th brain injury during small overlap barrier tests. Methods: To achieve this objective, a total of 24 vehicle crash loading curves were collected as input data for the multi-body simulation. Two commercially available mathematical dynamic models, namely H50th and THOR, were utilized to investigate the differences in head injury response. Subsequently, a decision method known as simple additive weighting was employed to establish a comprehensive brain injury metric by incorporating the weighted HIC and either DAMAGE or brain injury criterion. Furthermore, 35 sets of vehicle crash test data were used to analyze these brain injury metrics. Results: The rotational displacement of the THOR head is significantly greater than that of the H50th head. The maximum linear and rotational head accelerations experienced by H50th and THOR models were (544.6 ± 341.7) m/s2, (2468.2 ± 1309.4) rad/s2 and (715.2 ± 332.8) m/s2, (3778.7 ± 1660.6) rad/s2, respectively. Under the same loading condition during small overlap barrier (SOB) tests, THOR exhibits a higher risk of head injury compared to the H50th model. It was observed that the overall head injury response during the small overlap left test condition is greater than that during the small overlap right test. Additionally, an equation was formulated to establish the necessary relationship between the DAMAGE values of THOR and H50th. Conclusion: If H50th rather than THOR is employed as an evaluation tool in SOB crash tests, newly designed vehicles are more likely to achieve superior performance scores. According to the current injury curve for DAMAGE and brain injury criterion, it is highly recommended that HIC along with DAMAGE was prioritized for brain injury assessment in SOB tests.

Head injury criterion (HIC) companied by a rotation-based metric was widely believed to be helpful for head injury prediction in road traffic accidents. Recently, the Euro-New Car Assessment Program utilized a newly developed metric called diffuse axonal multi-axis general evaluation (DAMAGE) to explain test device for human occupant restraint (THOR) head injury, which demonstrated excellent ability in capturing concussions and diffuse axonal injuries. However, there is still a lack of comprehensive understanding regarding the effectiveness of using DAMAGE for Hybrid Ⅲ 50th percentile male dummy (H50th) head injury assessment. The objective of this study is to determine whether the DAMAGE could capture the risk of H50th brain injury during small overlap barrier tests. To achieve this objective, a total of 24 vehicle crash loading curves were collected as input data for the multi-body simulation. Two commercially available mathematical dynamic models, namely H50th and THOR, were utilized to investigate the differences in head injury response. Subsequently, a decision method known as simple additive weighting was employed to establish a comprehensive brain injury metric by incorporating the weighted HIC and either DAMAGE or brain injury criterion. Furthermore, 35 sets of vehicle crash test data were used to analyze these brain injury metrics. The rotational displacement of the THOR head is significantly greater than that of the H50th head. The maximum linear and rotational head accelerations experienced by H50th and THOR models were (544.6 ± 341.7) m/s2, (2468.2 ± 1309.4) rad/s2 and (715.2 ± 332.8) m/s2, (3778.7 ± 1660.6) rad/s2, respectively. Under the same loading condition during small overlap barrier (SOB) tests, THOR exhibits a higher risk of head injury compared to the H50th model. It was observed that the overall head injury response during the small overlap left test condition is greater than that during the small overlap right test. Additionally, an equation was formulated to establish the necessary relationship between the DAMAGE values of THOR and H50th. If H50th rather than THOR is employed as an evaluation tool in SOB crash tests, newly designed vehicles are more likely to achieve superior performance scores. According to the current injury curve for DAMAGE and brain injury criterion, it is highly recommended that HIC along with DAMAGE was prioritized for brain injury assessment in SOB tests. [ABSTRACT FROM AUTHOR]

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As was shown in the previous part of the study, windshields are an important part of the passive safety means of modern low-floor trams with an extraordinary effect on pedestrian safety in a pedestrian–tram collisions. Therefore, maximum attention must be paid to the definition of tram windshield characteristics. This article describes a windshield crash test, from which data are obtained to verify the feasibility of the applied computational approaches. A developed analytical model is utilised for a simple description of the energy balance during collision with an illustrative definition of the important parameters of laminated glass as well as their clear physical interpretations. The finite element analysis (FEA) performed in Ansys software using two versions of material definition, namely a simpler (*MAT_ELASTIC with nonlocal failure criterion) and a more complex (*MAT_GLASS with brittle stress-state-dependent failure) material model, which are presented as suitable for obtaining a detailed description of the shattering process of laminated glass, which can also be used effectively in windshield engineering. [ABSTRACT FROM AUTHOR]

This article represents the first paper in a two-part series dealing with safety during tram–pedestrian collisions. This research is dedicated to the safety of trams for pedestrians during collisions and is motivated by the increased number of lethal cases. The first part of this paper includes an overview of tram face development from the earliest designs to the current ones in use and, at the same time, provides a synopsis and explanation of the technical context, including a link to current and forthcoming legislation. The historical design development can be characterised by three steps, from an almost vertical front face, to leaned and pointed shapes, to the current inclined low-edged windshield without a protruding coupler. However, since most major manufacturers now export their products worldwide and customisation is only of a technically insignificant nature, our conclusions are generalisable (supported by the example of Berlin). The most advantageous shape of the tram's front, minimising the effects on pedestrians in all collision phases, has evolved rather spontaneously and was unprompted, and it is now being built into the European Commission regulations. The goal of the second part of this paper is to conduct a series of tram–pedestrian collisions with a focus on the frontal and side impacts using a crash test dummy (anthropomorphic test device—ATD). Four tram types approaching the collision at four different impact speeds (5 km/h, 10 km/h, 15 km/h, and 20 km/h) were used. The primary outcome variable was the resultant head acceleration. The risk and severity of possible head injuries were assessed using the head injury criterion (HIC15) and its linkage to the injury level on the Abbreviated Injury Scale (AIS). The results showed increasing head impacts with an increasing speed for all tram types and collision scenarios. Higher values of head acceleration were reached during the frontal impact (17–124 g) compared to the side one (2–84 g). The HIC15 values did not exceed the value of 300 for any experimental setting, and the probability of AIS4+ injuries did not exceed 10%. The outcomes of tram–pedestrian collisions can be influenced by the ATD's position and orientation, the impact speed and front-end design of trams, and the site of initial contact. [ABSTRACT FROM AUTHOR]

A rapid rise in the popularity of e-scooters has brought forth an increasing number of e-scooter-related conflicts, crashes, and injuries to pedestrians in many cities. There is a pressing need to understand the factors influencing the severity of injury to pedestrians involved in e-scooter collisions. This paper investigates the dynamics of e-scooter-pedestrian collisions and presents a new method for relating the probability of severe head injury to collision speed in e-scooter-pedestrian collisions. A total of 160 computer simulations representing different collision scenarios have been analyzed. Our results have shown that e-scooter speed is the main determinant of the severity of pedestrian head injury. E-scooter speed ranging from 10 to 15 km/h is found to be critical for pedestrian safety as the probability of severe head injury rises rapidly within this speed range. Moreover, an e-scooter-pedestrian collision is more likely to cause severe head injury to the pedestrian than a bicycle-pedestrian collision within the same speed range. It has also been found that the weight of the e-scooter and the direction of impact do not have a strong influence on the collision metrics, especially on the probability of severe head injury. The study has also investigated the post-collision fall mechanism for different pedestrian profiles and the influence of different impact angles. Finally, some recommendations have been proposed, including a speed limit of not more than 11 km/h for e-scooterist on shared paths where the likelihood of pedestrian and e-scooter conflicts is higher. The recommendations could help authorities develop legislation for safe micro-mobility.

In Malaysia, riding motorcycles is a popular mode of transportation, particularly in urban areas where traffic congestion is prevalent. Additionally, motorcycles are relatively affordable and have low fuel consumption, which makes them an attractive option for many. Per Malaysian traffic laws, riders must wear helmets while riding. As a result, various brands and types of helmets are available for purchase. However, with the increasing popularity of online shopping platforms, many individuals opt to purchase helmets online despite the uncertain quality control of these products. This study aims to assess the effectiveness of three different types of motorcycle helmets in protecting the head from injury. The helmet types evaluated in this unbiased study include fullface, open-face, and half-coverage helmets. The head injury predictors used in this study include Peak Linear Acceleration (PLA), Peak Rotational Acceleration (PRA), Head Injury Criterion (HIC), and Brain Injury Criterion (BrIC). Each helmet was subjected to an impact in a controlled environment using a 6-kg cylinder attached to a pendulum arm, with the impact directed at the front of the helmet at a speed of approximately 6 m/s. Full-face and open-face helmets performed exceptionally well in terms of linear parameters (PLA and HIC). The PLA and HIC of half-coverage helmets are nearly 70% and 50% higher than full-face and open-face helmets. All helmets perform poorly against rotational impact (PRA and BrIC). This shows that helmet design needs to be improved to enhance protection against rotational impact. This study represents the first case study in Malaysia to gather mechanical head injury data comparing the protective performance of different helmet types under both linear and rotational impact. These findings may provide a more accurate understanding of helmet performance in protecting against head injuries. [ABSTRACT FROM AUTHOR]

Existing robots rely on external sensors to detect and prevent potential human-robot collisions. However, with the growing demand for complex and high-speed human-robot interaction, robots with inherently safer actuators are becoming more desirable. Such robots offer robust protection against excessive impact force even when external sensors fail or become unavailable. Robot actuators with low reflected inertia and low effective stiffness are necessary to achieve mechanically safer human-robot interaction. This paper presents novel compliant actuators with high torque-to-inertia ratios and low torque-to-stiffness ratios without compromising the output torque and output stiffness of an actuator. Comparisons with existing actuators demonstrate that a robot with the proposed compliant actuators has a much lower effective mass sensed at the end-effector. Impact analysis is presented to verify the effectiveness of high torque-to-inertia ratios and low torque-to-stiffness ratios. To assess the performance of the proposed robot, a pose repeatability experiment is conducted, which shows that the end-effector position control precision is comparable to existing stiff robots despite the inherent compliance of the actuators. These compliant actuators can be used to build various human-friendly robots and are expected to improve the safety and reliability of human-robot interaction.

This paper employed finite-element simulation together with a human body model (HBM) — THUMS to study the head injury risk of a pedestrian involved in a frontal impact with a sedan car. While previous studies have gained an intensive understanding of the effects of various factors on pedestrian injury, their results were mainly based on standard-sized HBMs. Hence, a scaling procedure was first applied for the THUMS to obtain a model that possesses Vietnamese anthropometry. A total of thirty simulations were conducted to investigate the effect of various parameters, including impact angle, impact location, and impact speed, on the head injury criterion (HIC) of the scaled THUMS. Besides, each simulation covered not only the car-to-pedestrian impact but also the pedestrian-to-ground impact. Thus, the head injury of the pedestrian in both primary impact and secondary impact could be evaluated. Results showed that HIC increased consistently with impact speed for primary impact. An impact at the center of the car was more critical than that at the corner. Whereas, the effect of impact angle varied depending on the impact location. Regarding the secondary impact, HIC value was found to be highly sensitive to the posture of the pedestrian before impacting to the ground. In most cases, HIC was much higher in secondary impact than in primary impact. In other words, secondary impact poses a high risk of fatality to pedestrians in a traffic accident. [ABSTRACT FROM AUTHOR]

To reduce injuries to greyhounds caused by collisions with fixed racing track objects such as the outside fence or the catching pen structures, padding systems are widely adopted. However, there are currently neither recognised standards nor minimum performance thresholds for greyhound industry padding systems. This research is the first of its kind to investigate the impact attenuation characteristics of different padding systems for use within the greyhound racing industry for the enhanced safety and welfare of racing greyhounds. A standard head injury criterion (HIC) meter was used to examine padding impact attenuation performance based on the maximum g-force, HIC level and the HIC duration. Initially, greyhound racing speed was recorded and analysed with the IsoLynx system to understand the potential impact hazard to greyhounds during racing which indicates the necessity for injury prevention with padding. A laboratory test was subsequently conducted to compare the impact attenuation performance of different kinds of padding. Since padding impact attenuation characteristics are also affected by the installation and substrate, onsite testing was conducted to obtain the padding system impact attenuation performance in actual greyhound racing track applications. The test results confirm that the padding currently used within the greyhound industry is adequate for the fence but inadequate when used for rigid structural members such as the catching pen gate supports. Thus, increasing the padding thickness is strongly recommended if it is used at such locations. More importantly, it is also recommended that, after the installation of padding on the track, its impact attenuation characteristics be tested according to the methodology developed herein to verify the suitability for protecting greyhounds from injury.

The Hybrid III 50th percentile (H350) Anthropomorphic Test Devices (ATD) is the most widely used crash test dummy to identify the best seatbelt and airbags configuration for frontal impact load cases. However, the H350 was developed based on the United States (US) anthropometric size, back in 1976. In other words, the restraint system optimized using the H350 is not optimized for other populations. To investigate this issue, a finite element model of Hybrid III 50th percentile (H350M) of Malaysian population was developed and analysed in this work. Validation of the new biofidelity corridors was performed to ensure that this newly crash test dummy can represent the population under consideration. In this study, the H350M was integrated into a finite element vehicle model, to simulate a frontal rigid barrier crash load case performed at 56 km/h and compared with the existing H350. The H350 integrated vehicle-occupant simulation model has been correlated with a physical test. The model managed to achieve the average Correlation and Analysis (CORA) rating of 0.722. The simulation results showed that the newly H350M experienced a higher head acceleration, Head Injury Criterion (HIC15), 3 ms chest acceleration and chest displacement compared to the H350, as they were increased from 64.3 g to 70.6 g, 370 to 542, 49.6 g to 52.6 g, and from 26.5 mm to 26.6 mm, respectively. Generally, higher head acceleration, HIC15 and chest displacement lead to higher injuries during frontal crash accidents. Hence, the recommendations to reduce injuries are also discussed and explored in this study.

The Hybrid III 50th percentile (H350) Anthropomorphic Test Devices (ATD) is the most widely used crash test dummy to identify the best seatbelt and airbags configuration for frontal impact load cases. However, the H350 was developed based on the United States (US) anthropometric size, back in 1976. In other words, the restraint system optimized using the H350 is not optimized for other popula- tions. To investigate this issue, a finite element model of Hybrid III 50th percentile (H350M) of Malaysian population was developed and analysed in this work. Validation of the new biofidelity corridors was performed to ensure that this newly crash test dummy can represent the population under consideration. In this study, the H350M was integrated into a finite element vehicle model, to simulate a frontal rigid barrier crash load case performed at 56 km/h and compared with the existing H350. The H350 integrated vehicle-occupant simulation model has been correlated with a physical test. The model managed to achieve the average Correlation and Analysis (CORA) rating of 0.722. The simulation results showed that the newly H350M experienced a higher head acceleration, Head Injury Criterion (HIC15), 3 ms chest acceleration and chest displacement compared to the H350, as they were increased from 64.3 g to 70.6 g, 370 to 542, 49.6 g to 52.6 g, and from 26.5 mm to 26.6 mm, respectively. Generally, higher head acceleration, HIC15 and chest dis- placement lead to higher injuries during frontal crash accidents. Hence, the recommendations to reduce injuries are also discussed and explored in this study. [ABSTRACT FROM AUTHOR]

This study evaluates the effectiveness of various widely used head injury criteria (HICs) in predicting vulnerable road user (VRU) head injuries due to road traffic accidents. Thirty-one real-world car-to-VRU impact accident cases with detailed head injury records were collected and replicated through the computational biomechanics method; head injuries observed in the analyzed accidents were reconstructed by using a finite element (FE)-multibody (MB) coupled pedestrian model [including the Total Human Model for Safety (THUMS) head–neck FE model and the remaining body segments of TNO MB pedestrian model], which was developed and validated in our previous study. Various typical HICs were used to predict head injuries in all accident cases. Pearson’s correlation coefficient analysis method was adopted to investigate the correlation between head kinematics-based injury criteria and the actual head injury of VRU; the effectiveness of brain deformation-based injury criteria in predicting typical brain injuries [such as diffuse axonal injury diffuse axonal injury (DAI) and contusion] was assessed by using head injury risk curves reported in the literature. Results showed that for head kinematics-based injury criteria, the most widely used HICs and head impact power (HIP) can accurately and effectively predict head injury, whereas for brain deformation-based injury criteria, the maximum principal strain (MPS) behaves better than cumulative strain damage measure (CSDM0.15 and CSDM0.25) in predicting the possibility of DAI. In comparison with the dilatation damage measure (DDM), MPS seems to better predict the risk of brain contusion.

In the crashworthiness of the vehicle, the head injury criterion is the most significant factor in the injury rate. Crash optimization has been employed to enhance the head injury criterion value. Since the head injury criterion value is calculated from acceleration, a surrogate-model-based crash optimization method is generally used. However, when the number of design variables increases, the cost of analysis increases extremely. Conceptual design such as topology optimization is difficult to apply since it has many design variables. A crash optimization methodology that considers the head injury criterion value is proposed based on the equivalent static loads method. The proposed method calculates the head injury criterion value using the finite difference method, and the channel frequency classes filter during linear static-response structural optimization with the equivalent static loads. Two practical large-scale problems are solved to validate the proposed method. For the headform impact on the upper interior, size optimization is carried out to satisfy the constraint on the head injury criterion value while the mass is minimized. Topology optimization is performed in the case of the hood headform impact. The material distribution of the inner panel in the hood is determined to minimize the head injury criterion value. [ABSTRACT FROM AUTHOR]

Purpose: Motor vehicle crashes are one of the leading causes of traumatic brain injuries. Restraint systems of cars are evaluated by crash tests based on human tolerance data, however, the reliability of data currently used has been questioned several times in the literature due to the neglect of certain types of effects, injury types and uncertainties. Our main goal was to re-evaluate the currently applied risk curve by taking the previously neglected effects into account. Methods: In this paper, the probability of traumatic brain injury was determined by reliability analysis where different types of uncertainties are taken into account. The tissue-level response of the human brain in the case of frontal crashes was calculated by finite element analyses and the injury probability is determined by Monte Carlo simulations. Sensitivity analysis was also performed to identify which effects have considerable contribution to the injury risk. Results: Our results indicate a significantly larger injury risk than it is predicted by current safety standards. Accordingly, a new risk curve was constructed which follows a lognormal distribution with the following parameters: μLN = 6.5445 and σLN = 1.1993. Sensitivity analysis confirmed that this difference primarily can be attributed to the rotational effects and tissue-level uncertainties. Conclusions: Results of the tissue-level reliability analysis enhance the belief that rotational effects are the primary cause of brain injuries. Accordingly, the use of a solely translational acceleration based injury metric contains several uncertainties which can lead to relatively high injury probabilities even if relatively small translational effects occur. [ABSTRACT FROM AUTHOR]

In youth association football, the use of different size and/or mass footballs might represent a feasible intervention for addressing heading impact severity and player safety concerns. This study assessed the effects of football size and mass on head impacts based on defensive heading in youth football. Three-dimensional trajectories of U16 youth academy free kicks were modelled to derive three impact trajectories, representing defensive heading in youth football. Three football models (standard: S5, standard-light: S5L, and small: S4) impacted an instrumented headform; Head Injury Criterion (HIC15) and Rotational Injury Criterion (RIC15) were calculated. For headform impacts, S4 and S5L footballs yielded lower HIC15 magnitudes than S5 footballs. Further, S4 footballs yielded lower HIC15 and lower RIC15 magnitudes than S5 and S5L footballs. Initial findings indicated that smaller, S4 footballs reduced linear and rotational head injury criteria for impacts representative of defensive heading in youth football.

In this study, head injury criteria (HIC) and chest severity index (CSI) assessments are made based on finite element simulation. Simulations are carried out through nonlinear finite element analysis software LS-Dyna. The effect on the occupant’s injury of introducing aluminum alloy, AA5182, to automotive side members is highlighted in comparison to the existing model made of steel. The HIC and CSI are taken as the evaluation criteria. The injury criteria are assessed under two impact conditions: full frontal and oblique. The aim of this paper is to analyze the effect of lightweight materials on occupant crash protection. It was shown that the introduction of AA5182 provides a 30.77% reduction in mass while improving the HIC and CSI performance in full frontal impact; whereas only CSI is improved in oblique impact.

The design of an adaptive helmet suspension system that provides optimized head protection under variable impact conditions is reported. The adaptive response is achieved through the use of rate activated tethers (RATs), a flexible strap-like material that uses shear thickening fluids to generate speed-sensitive extensional resistance. The RATs are integrated into a helmet by replacing the webbing system of a traditional construction hardhat with a network of RATs, and performing impact attenuation testing over a range of velocities. Impacts to the crown region of the helmet demonstrate a 50% reduction in peak acceleration experienced by the headform for impact velocities between 1.5 and 3.5 m/s compared to the conventional webbing system, and comparable response to the conventional system at 4.5 m/s. Complementary RAT extensional testing and low velocity helmet compression tests confirm that the rate-sensitive response of the RATs contributes significantly to improved system performance. Additionally, calculations for suspension model systems show that the steady yield force exhibited by RATs over long strokes is a critical feature for minimizing head acceleration, and that the RAT suspension systems are achieving responses remarkably close to the ideal suspension response. [ABSTRACT FROM AUTHOR]

Nowadays, safety is a competitive advantage for automotive products and therefore receives considerable attention by automotive research centers. In this paper, a frontal crash test of sedan product of an under development platform is simulated and occupant head injuries are investigated based on ECE R94 regulation. First, an initial evaluation of the crash behavior of the sedan car is carried out and then airbag, dummy and seat belt are added to the model to study occupant head injuries under crash test. In this study, peak head acceleration and head injury criteria (HIC36) are considered as two output parameters based on ECE R94 regulation. Considering these two output parameters, sensitivity analysis and optimization are performed using Taguchi and analysis of variance (ANOVA) methods. In this way, airbag distance to dummy, trigger time, initial inflator gas temperature and tank pressure are considered as input parameters. Obtained results show that in all computer experiments designed by Taguchi responses values satisfy the requirements of ECE R94. Two different out-of-position conditions are considered by reducing the distance between dummy and airbag relative to the optimum design obtained by Taguchi. The worst case of design and its response values are also predicted using Taguchi. Finally, re-evaluating finite element analyses are performed based on the optimum and the worst cases. The results of these simulations show the validity of approach of this paper. [ABSTRACT FROM AUTHOR]

As an important component of a vehicle, the automotive windshield glazing normally consists of two glass sheets bonded with one polyvinyl butyral (PVB) film. In the context of pedestrian-vehicle accidents, the impact cracking mechanism of the windshield is conductive to pedestrian safety protection and traffic accident reconstruction. The purpose of this paper is to validate the capacity of the intrinsic cohesive zone model (CZM) in impact fracture simulations of a windshield. A windshield finite element (FE) model is established, where cohesive elements are inserted into all the common faces between glass hexahedral finite elements. The fracture behavior of a windshield impacted by a standard adult headform impactor is simulated with the commercial explicit finite element code LS-DYNA. Numerical simulation results are validated by comparison with the corresponding experimental outcomes. For comparison, additional simulations have been performed by the widely used element deletion method (EDM) with a plasticity strain failure criterion. Simulation results show that the intrinsic CZM is more suitable to capture the impact failure characteristics of windshield. Finally, the effects of the glass cohesive strength, mechanical properties of PVB and interfacial adhesion on the impact fracture behavior of the windshield are investigated. [ABSTRACT FROM AUTHOR]

This study compares drop tower tests of four commonly used football helmets, under the National Operating Committee on Standards for Athletic Equipment (NOCSAE) football helmet standard, to show that the tests need modification to include the facemask. In our study, the need for a more robust systematic approach to football helmet testing procedures is emphasized by comparing the Head Injury Criterion (HIC), the Gadd Severity Index (SI), and peak acceleration values for different helmets at different locations on the helmet under modified NOCSAE standard drop tower tests. Drop tests were performed on four modern football helmets at eight impact locations (front, front boss, side, rear, rear boss, top, front top, and front top boss), two different impact velocities (5.46 and 4.88 m/s), and two helmet configurations ('with facemasks' and 'without facemasks'). Statistically significant differences ( p < 0.05) were found in 41% of the comparisons between 'with facemasks' and 'without facemasks'. Addition of the facemask resulted in an increased HIC, SI, and peak acceleration response measures in 62% of these cases. For example, the stiffening boundary conditions arising from the attached facemask can decrease the helmet performance by up to 50% depending on the impact location when considering the peak acceleration ( p < 0.001) as a metric. In terms of location, the top and front top impacts gave the largest HIC, SI, and peak acceleration values. In summary, these comparative drop test results revealed that the current NOCSAE test methods need improvement by attaching the facemasks to helmets and by including two new helmet impact locations (front top and front top boss). The modified NOCSAE football helmet standard test gives a more accurate representation of a helmet's performance and its ability to mitigate on-field impact. [ABSTRACT FROM AUTHOR]

Bicycle riders are among the highest risk group in traffic. A cyclist simulation study captured kinematics and injuries to legs, pelvis, neck, and head for one human body size. We analyzed the number of parameters (forces acting on left and right tibia, head injury criterion, neck tensile force, neck shear force, and pelvic acceleration) for each of the four different cases: bicyclist ride out-residential driveway, motorist overtaking-undetected bicyclist, bicyclist left turn-same direction, and bicyclist right turn-opposite direction. The comparison of simulation outcomes for leg injuries with official hospital records has shown a very good correlation in terms of injury severity prediction. This study concludes that if countermeasures to prevent fatal cyclist injury in car impacts were to be concentrated on mitigating head and neck impact to the windscreen of the car, a dominant share of fatal cyclist crashes and severe traumatic head injury cases at collision speeds exceeding 40 km/h could be prevented. [ABSTRACT FROM AUTHOR]