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The aim of this study was to investigate the feasibility of rider-worn pelvis protection for mitigating injury risk when contacting the motorcycle fuel tank in a crash. A newly developed test apparatus was designed and constructed to simulate the interaction between a rider's pelvis and the motorcycle fuel tank in a frontal crash. Impacts were performed at a velocity of 18 km/h into four motorcycle fuel tanks. Further testing used a rigid fuel tank surrogate and the pelvis surrogate in an unprotected condition and with a series of impact protector prototypes. A subset of prototype samples was also tested at varying tank angles (30°, 37.5°, 45°) and impact speeds (8.5 km/h, 13 km/h, 18 km/h). Analysis of variance was used to determine whether the protector prototypes reduced pelvis response compared to unprotected. Resultant peak pelvis acceleration was reduced by three pelvis impact protector prototypes compared to an unprotected condition. The reduction in peak acceleration occurred without a significant change in the peak pelvis rotational velocity. The pattern of protector performance was consistent at varying fuel tank angles but only reduced the pelvis response at the highest impact speed tested of 18 km/h. The results indicate that there may be potential for using pelvis impact protection to mitigate injury risk by absorbing and/or distributing impact energy that would otherwise be transmitted to the rider's pelvis. However, due to the current paucity in understanding of pelvis biomechanics to anteroposterior loading, it is unknown whether the pelvis acceleration reductions achieved would prevent injury. [ABSTRACT FROM AUTHOR]

Head-first compressive impacts occur in motorcycle crashes and may result in serious to fatal neck injuries to riders. Equipment to protect the riders' necks from these injuries are available in the market; however, their effectiveness in reducing injury risk is not clear, either due to the lack of scientific evidences or assessment with any prevalently accepted standard. This paper presents a finite element ligamentous neck model, developed as a computationally efficient tool, for future use in the computational phase of assessment process of neck protective equipment. The 3D cervical spine was generated using the mean statistical dimensions of vertebrae and proposed constitutive models, provided in the scientific literature. Ligaments, for the vertebra-vertebra and Hybrid III head–vertebra ligamentous joints, were introduced with the aid of published anatomical descriptions. For validation, the response of the head-neck system under compressive loadings and the flexion-extension bending stiffness of the neck at the segment level were compared against experimental data. The advanced CORrelation and Analysis (CORA) algorithm was applied on the validation responses to assess biofidelity of the model. The results indicate that the model is functional and meets ISO/TR9790 standard as a "good" biofidelic model. [ABSTRACT FROM AUTHOR]

Nowadays crash helmets are tested by dropping a free or unrestrained headform in Europe but a guided or restrained headform in the United States. It remains unclear whether the free fall and the guided fall produce similar impact kinematics that cause head injury. A finite element helmet model is developed and compared with experimental tests. The resulting head kinematics from virtual tests are input for a finite element head model to compute the brain tissue strain. The guided fall produces higher peak force and linear acceleration than the free fall. Eccentric impact in the free fall test induces angular head motion which directs some of the impact energy into rotational kinetic energy. Consequently, the brain tissue strain in the free fall test is up to 6.3 times more than that in the guided fall. This study recommends a supplemental procedure that records angular head motion in the free fall test. [ABSTRACT FROM AUTHOR]

A study about the response of motorcycle helmets to impacts is described in this paper and possible ways to improve current designs are discussed. Firstly, a simple unidimensional model of helmet is analyzed and the main parameters that affect its response are pointed out. Subsequently, the generation and testing of the Finite Element model of a commercially available helmet are described and numerical results are compared to experimental results. Finally, the FE modeled is used to compare different design configurations. [ABSTRACT FROM AUTHOR]