### EVALUATING THE INFLUENCE OF THE PARAMETERS THAT CHARACTERIZE THE TRAFFIC INCIDENTS BY USING THE SENSITIVITY ANALYSIS OF THE OBTAINED RESULTS

Adrian TODORUŢ, Nicolae CORDOȘ, Monica BĂLCĂU, Alexandru TOACĂ

#### Abstract

This paper analyses the possibilities available for the reconstruction of the retrospective stages of road incidents of a vehicle-vehicle type, by following the evaluation of the velocities before the collision and determining the influence of certain parameters on the obtained results. A fist case study we modified the angle before the collision of a vehicle involved in an incident and we observed its influence on the velocity before the collision. The second case study modified the mass of one of the vehicles and we observed its influence on the velocity before the collision. The main reasons for choosing these two parameters as variables are: the angle before the collision can be changed by the driver without knowing by observing a potential incident situation, in an attempt to avoid the collision; we chose changing the mass of one of the vehicles because it is very seldom that studies take into account the real mass of the vehicle, most of the times the reports take into account the own mass of the vehicle or its total mass, according to the technical specifications. Given the fact that the reconstruction of the stages of traffic incidents are done with the help of conservation of energy, one can use one of the most used methods, namely the method of conservation of energy and the method of conservation of momentum. Thus, taking into account the physical models of the traffic incidents studied, based on the method of conservation of momentum and using mathematical modelling, we can calculate the velocities before the collision of the vehicles. In this respect, we studied two traffic incidents. Because the initial data were based on schematics taken at the site, testimonials, etc., we studied various methods for uncertainty analysis. We studied the level of confidence of the results obtained and a sensitivity analysis of certain variable parameters, thus identifying an interval for the output data, that is, the velocities before the collision with a certain degree of certainty.

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