To sufficiently display the function as an alarm for a contact possibility without making a driver feel troublesome.
When an own vehicle is running on an ascending road (step S22), a threshold value and a control gain which become parameters for the alarm for a contact possibility are made smaller in response to the gradient of the ascending road (step S22). When the own vehicle is running on a descending road (step S23), the threshold value and the control gain are made larger in response to the gradient of the descending road. The threshold value specifies the alarming timing of the alarm for the contact possibility, and the control gain specifies the strength of the alarm (braking force). Therefore, when the own vehicle is running on the ascending road, for the alarm for the contact possibility, the alarming timing becomes later, and the strength becomes weaker. In the meantime, when the own vehicle is running on the descending road, for the alarm for the contact possibility, the alarming timing becomes earlier, and the strength becomes stronger.
KIMURA TAKESHI
NAITOU MOTOHIRA
USUI HISATAKA
Yoshiaki Naito
Cui Shu Tetsu