Occupant Behavior During a One-Lane Change Maneuver Resulting from Autonomous Emergency Steering

The safety of vehicle occupants has evolved recently due to the market implementations of new sensing technologies that enables predicting and identifying hazardous road traffic situations and thus actively prevent or mitigate collisions. The obvious benefits of the active safety systems has also been recognized and acknowledged by the regulatory and consumer bodies responsible for transportation, and as a result, the new standards, regulations and public rewards are being introduced. The active safety systems can prevent or mitigate collisions by controlling the motion of the vehicles through autonomous actuation of either: braking, steering or both simultaneously. The autonomous control of the vehicle inevitably affects the motion of the travelling occupants with respect to the vehicle interior. Depending on the severity of the maneuver, the occupant motion may lead to non-optimal postures for the in-crash phase if the collision is unavoidable or may impair the capability of a driver to resume the control of a car after the autonomous evasive maneuver. These considerations create the direct need for developing the active systems together with passive systems with the ultimate objective to best protect the occupants. This paper presents a simulation methodology for developing new automotive safety systems in an integrative manner that ensures optimal exploitation of benefits of active and passive systems. It also presents the simulation results of the study into the occupant behavior during the emergency evasive maneuver. The investigation was performed using the combination of newly available simulation techniques for modelling the Advanced Driver Assistance Systems (PreScan software) and for modelling the real human behavior under low-g conditions (MADYMO software). The results obtained showed the severity of the out-of-position occupant postures created by the autonomous evasive system. It was also observed that the lateral acceleration, being the effect of the maneuver, may cause the driver to impact the b-pillar, and thus potentially impair the further driving capabilities. The study was performed based on the numerical simulations and some of the model components were not fully validated. Further investigations will follow and will be focused on additional validation of the method and its components and finally on quantitative assessment of the revealed problems. The presented methodology and its application for investigating the occupant behavior under low-g loading shows the relevance of developing the new safety systems in an integrative manner. The simulation methods and techniques will play significant role in the integrated safety systems development processes, allowing to test the conditions of high complexity in order to represent the real life scenarios and thus ensuring better occupant protection.