Human body model muscle activation influence on crash response
Whole-Sequence simulations consisting of a pre-crash manoeuvre and a crash scenario were carried out to investigate the effect of muscle activation on Human Body Model (HBM) kinematics and injury predictions during crash. A full factorial combination of two pre-crash manoeuvres (Braking and Left Turn), three crash scenarios (two frontal impacts and one Far-Side impact), and four muscle activation strategies (controllers Off, Active, Hold at a constant control signal and with a Startle response) were run. It was found that for the frontal impacts, the muscle activation did not have any considerable effect on the kinematic response, however HBM injury predictions were affected in the higher acceleration frontal impact. For the Far-Side impact, there was a moderate effect on kinematics in the form of reduced peak inboard head excursion with active muscles. The recommendation from the study is that muscle activations should also be included in the crash-phase of Whole-Sequence simulations to enable HBM simulation to better represent live occupants. However, as the postural control algorithm appears to give high muscle activations during the crash-phase, a strategy to hold the muscle activations constant during the crash is recommended for now.