A vehicle driving assist system calculates a risk potential of the subject
vehicle with respect to a front obstacle by estimating a compression
amount of a vertical resilient member which is imaginary provided at the
front of the subject vehicle when the subject vehicle approaches the
front obstacle. The correction amounts of drive force and braking force
and the correction amount of reaction force are calculated based upon the
calculated risk potential so as to perform drive force/braking force
correction control and reaction force control simultaneously.