Development of a new lumped-parameter model for vehicle side-impact safety simulation

Abstract

The current paper describes a simple and yet comprehensive lumped-parameter model (LPM) for simulating the National Highway Traffic Safety Administration (NHTSA) side-impact safety tests for passenger vehicles. The LPM includes new lumped masses, not previously reported in a single multibody model, for key vehicle side-structure systems identified with the help of an energy-based study conducted using explicit finite element analysis of two passenger vehicles. In addition to the vehicle side structure, lumped masses for the NHTSA side-impact barrier and ‘rest of vehicle’, the latter implying the mass of the vehicle minus the combined mass of the side-structure subsystems considered in the LPM, have been incorporated so that the total mass of the system corresponds to that of an actual vehicle—barrier system in a NHTSA side-impact test (Lateral Impact New Car Assessment Program (LINCAP) or FMVSS 214). The lumped masses are interconnected with elastic—plastic springs. A unique feature of the present model is the inclusion of two lumped side-impact dummies for obtaining predictions of the front and rear (thoracic trauma index (TTI)). The validity of the present LPM is established by performing LS-DYNA-based LINCAP simulations of two real-world vehicles, namely the Dodge Neon and Dodge Intrepid, and obtaining a reasonably good correlation of the computed structural and occupant responses as well as TTI (front and rear) with the corresponding test results reported by the NHTSA.

Further results on mathematical models of vehicle localized impact

“…To investigate what are parameters C and t m of such a model, first we need to find the spring stiffness k. By substituting (6) to (4) …”

“…It is an analytical method of formulating a model which can be further used for simulation of a real event. It allows us to establish dynamic equations of the system -differential equationswhich give the complete description of the model's behavior, see the references [6] and [7]. To be able to analyze a given collision, it is often enough (and more efficient) not to examine the complicated crash pulse but just to study its approximation.…”

Investigation of vehicle crash modeling techniques: theory and application

“…The secondary approach frequently utilized in vehicle crash modeling is lumped parameter modeling of viscoelastic systems [8][9][10][11][12][13][14][15][16]. Structural parameters of models like damping or stiffness are estimated based on a given crash scenario.…”

Development of lumped-parameter mathematical models for a vehicle localized impact

“…It allows us to establish dynamic equations of the system -differential equations -which give the complete description of the model's behavior, see Refs. [9] and [10].…”