A collision avoidance judging section is provided which, based on a relative
connection
between own vehicle and preceding vehicle, carries out a judgment as to whether
or not a possible collision is avoidable by operating at least one of a steering
wheel and a brake pedal, and a collision avoidance estimating section is provided
which, based on the relative connection, carries out an estimation as to whether
or not, after expiration of a predetermined time from the time of detection of
the relative connection, a possible collision is avoidable by operating at least
one of the steering wheel and brake pedal. When the collision avoidance estimating
section estimates that the possible collision is unavoidable, a lower braking force
is produced, and when the collision avoidance judging section judges that the possible
collision is unavoidable, a higher braking force is produced.
