Obstacle avoidance relevant to risk judgment based on full-scale and driving simulator experiments

The aim of this paper is to clarify the relationship between vehicle behavior at obstacle avoidance and driver risk judgment in consideration with the situations of expected and unexpected obstacle appearance. Experiments were examined not only on the proving ground and on normal road but also in the JARI Driving Simulator. Results show that, 1) the avoidance time which allows no risk judgment was verified, that is the obstacle should be sensed at least 2 seconds before the collision, when taking account of the driver´s cognition and decision times, and 2) the results between full-scale and driving simulator experiments were consistent with each other and consequently it is shown that the driving simulator is effective for investigating such an emergency situation.