Work of non-elastic deformation against the deformation ratio of the Subcompact Car Class using the variable correlation method

Przemysław Kubiak

doi:10.1016/j.forsciint.2018.03.033

Work of non-elastic deformation against the deformation ratio of the Subcompact Car Class using the variable correlation method

Forensic Sci Int. 2018 Jun:287:47-53. doi: 10.1016/j.forsciint.2018.03.033. Epub 2018 Mar 27.

Author

Przemysław Kubiak¹

Affiliation

¹ Department of Vehicles and Fundamentals of Machine Design, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland. Electronic address: przemyslaw.kubiak@p.lodz.pl.

PMID: 29653318
DOI: 10.1016/j.forsciint.2018.03.033

Abstract

The presented study considers a Subcompact Car Class in a new non-linear method utilising the work W of car deformation defined as an algebraic function of deformation ratio Cs. In order to develop the experimental data, the method of variable correlation is utilised. Data from the NHTSA (National Highway Traffic Safety Administration) database comprising numerous frontal crash tests are used for the determination of mathematical model parameters. In the non-linear method used up until now, the so-called energetic approach, collisions are treated as non-elastic. The velocity threshold that defines the elastic collision was set to be 11km/h. Such an approach, which is very simplified, determines the linear dependence of energy lost during deformation on deformation coefficient Cs. This coefficient is calculated as a mean value, taking into account the weights of deformation points C₁-C₆. In this paper, the authors propose a more precise non-linear method in order to determine the work of deformation, and have used the more complex form of deformation coefficient.

Keywords: Car accidents; Car crash reconstruction; Crash test; Deformation ratio; Equivalent Energy Speed; Non-linear method; Subcompact.