Without being able to evaluate blunt thoracic trauma in terms of an acceptable injury criterion, it is not possible to develop or validate non-lethal projectiles, bullet proof vests and chest protectors for sports personnel etc. In order for the assessment of the blunt trauma caused by high speed projectiles, a novel design of a mechanical surrogate of the thorax (Mechanical THOrax for Trauma Assessment: MTHOTA) was conceptualized. An iterative impact analyses in the virtual testing environment were carried out by impacting the finite element model of the mechanical thorax with 37 mm diameter, 100 mm long wooden baton weighing 140 grams (20 m/s and 40 m/s impact speeds) and 37 mm diameter, 28.5 mm long wooden baton weighing 30 grams with 60 m/s impact speed. From the output of every simulation, force dynamic response (force-time), deflection dynamic response (deflection-time) and force-deflection response were elicited and compared with the corresponding human response corridors developed by Wayne State University's researchers. By suitably changing the design parameters of the mechanical surrogate, simulation iterations were continued till the responses were correlated with the human response corridors. Values of viscous criterion (VC max ), product of maximum chest deflection and the rate at which chest deforms, obtained from MTHOTA were in very good agreement with those obtained from the cadaveric test data. The methodology, concept and validation of the MTHOTA have been presented in this paper.

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Abstract. Less lethal kinetic ammunitions with soft noses such as eXact iMpact 1006, National Sports Spartan and B&T have been commonly used by military and law enforcement officers in the situations where lethal force is not warranted. In order to explore new materials to be used as nose in such ammunitions, a scholastic study using finite element simulations has been carried out to evaluate the effectiveness of two rubber like elastomers and a polyolefinic foam (low density, highly compressible, stiff and closed cell type of thermos plastic elastomer). State-of-the art thorax surrogate MTHOTA has been employed for the evaluation of blunt thoracic trauma. Force-rigid wall method was employed for the evaluation of head damage curves for each material. XM 1006 has been used as the benchmark projectile for the purpose of comparison. Both blunt thoracic trauma and head damage criterion point of view, both rubbers (R1 and R2) have yielded high values of VC max and peak impact force. Polyolefinic foam (F1) considered in the study has yielded very promising VC max values and very less peak impact force when compared with those of bench mark projectile XM 1006.

In Australia, few hundreds of vehicle crashes involving animals are being recorded every year. In order to protect the headlights, radiator, engine and bonnet from getting damaged and also to improve the occupant safety, many cars are equipped with vehicle front protection system (VFPS) which are either 'over the bumper' or 'bumper replacement' type. VFPS alters the crush characteristics of the vehicle and in turn affects the airbag triggering characteristics. Hence, non-airbag compliant VFPS would cause more serious damage to the vehicle and potentially serious injuries to the occupants instead of offering additional safety in the event of animal strike or low speed crash. Though FPS is a very common accessory for all passenger vehicles in Australia, not much research is published in regards to the airbag compatibility and other requirements to comply with the safety standards and Australian design rules pertaining to the VFPS. Authors have devised a CAE simulation based methodology to develop airbag compliant VFPS requiring minimum number of vehicle crash tests. In this paper, authors have presented various aspects related to the VFPS design such as styling, mounting points, mounting brackets, material specifications, weight requirement and endurance life, along with the CAE methodology to acquire the airbag compliant VFPS.