1. This work aims at optimizing a helmet. First a discrete dynamic model of a helmet has been proposed for modeling the free fall of the helmet from a height of 2m. The model was solved using Runge Kutta method. The time history of head acceleration has been extracted from this solution and ‘Time bound peak acceleration criteria’ of head injury has been computed After preparing the model it was validated using the available experimental and FEM results. The model was then used for optimization. The objective of optimization is to minimize ‘time bound peak acceleration’ which is taken as an injury criterion representing the effectiveness of the helmet. The optimization is subjected to constraints of maximum total mass and maximum total thickness of the helmet. The optimization has been carried out using conventional method as well as genetic algorithms. Subsequently the sensitivity of the objective function value with respect to different design parameters was studied.

2. The windshield of a car is impacted by pedestrians and riders of two-wheeled vehicles (with or without helmets) in a large proportion of road traffic crashes. This paper reports work on development of a FEM model in PAMCRASH for head windshield impact from outside the car.. This includes a helmet mode and a windshield model. Helmet drop test data, impact data for a standard headform without helmet impacting a windshield and impact data for headform with helmet impacting the windshield is used to verify the model.

1. Development of FE models for human body parts for impact simulation.

1. S Mukherjee, A Chawla et al, Modeling of head impact on laminated glass wind shields, Proceedings of IRCOBI 2000, Montpellier, France, September 2000

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