PTW Passive Safety: Numerical Study of Standard Impact Scenarios with Rider Injury Risk Assessment

Abstract

Powered two-wheeler (PTW) riders and passengers are among the group of vulnerable road users (VRU). This group uses the road transportation system together with other better-protected users such as passenger cars and truck drivers. The main vulnerability of PTW rider lies in their unequal position during the crash, due to the inability of application of the crashworthiness concept during the PTW vehicle design. This inequality could be somehow mitigated by the design of personal protective equipment (PPE). Mostly the design of the PPE’s is led by the standards which often are obsolete and takes into account only simple drop-tests (ECE 22.05). Those tests did not take into account complicated kinematics of the motorcycle accidents and biomechanics of the human body (the assessment is based only on the linear acceleration of the headform center of gravity). The authors propose a virtual approach for the PTW rider injury risk assessment, which coupled with the pre-impact conditions, could be used for the new PPE protection standards preparation. In this paper, authors want to present a numerical study on the most common PTW impact scenarios, which are described in ISO 13232. The simulations of the accidents were conducted in the VPS numerical environment (PAM-Crash explicit solver). Accidents participants, namely opposite vehicle (OV) modeled by finite element method (FEM) approach, powered two-wheeler (PTW) modeled by multibody system (MBS) approach, PTW driver represented by hybrid FE-MBS human body model Virthuman and a helmet (modeled by FE approach) were coupled to represent the 7 most common accident scenarios. The helmet is the only PPE enforced by the law, but not in all territories (Afghanistan, Dominica, Guyana, Mexico, Libya, Senegal, USA). Due to the complexity of the OV FE model, there was a necessity of model simplification and revalidation, which also was done in this work. The results of the simulations were examined with special emphasis on realistic representation of real accident kinematics. In each configuration, an injury risk assessment was done on the PTW rider model. The assessment was done based on injury criterion used by the NCAP, UNE 135900 and the LNL criterion. The paper shows that the virtual approach using the Virthuman human body model could be used for the simulation of PTW accidents. The results of this paper could be used for future PPE design.