Globally, powered two-wheeler (PTW) riders constitute a vulnerable road user group. This study aims to enhance the understanding of thoracic loading experienced by PTW riders in one of the most common crash configurations, PTW front to passenger car side (PFCS) impacts. A scoping review of the literature identified impact parameters describing common thoracic loading in terms of direction, location, distribution, and magnitude.

Four experimental hub and bar post-mortem human subject (PMHS) test series, covering some of the identified variations in thoracic loading, were selected to validate the thorax of the SAFER human body model (HBM). The SAFER HBM demonstrated fair kinetics and kinematics biofidelity for frontal and oblique hub impacts and poor to fair biofidelity for the bar impacts. However, the SAFER HBM can accurately predict the rib fracture risk estimated from the PMHS tests.

The findings demonstrate the potential of current HBMs to represent PTW-specific thoracic loading and support development of PTW rider safety systems in upright PFCS impacts. It also highlights a need for novel PMHS tests, in particular ones where the thorax is loaded above mid sternum and preferably including a vertical force component.