Method and system of driving assistance for collision avoidance

System of driving assistance for assisting a human driver in safely driving a vehicle called host vehicle, comprising a host vehicle equipped with an on-board processing unit, the host vehicle comprising means for obtaining first information relative to the trajectory of the host vehicle and means for obtaining second information relative to the trajectory of at least one other vehicle in a neighborhood of the host vehicle, said first and second information being obtained at regular time instants, said on-board processing unit comprising a collision risk assessment unit and a decision making unit adapted to trigger an intervention of a collision avoidance system,

• the system being characterized in that it further comprises means for intervention decision adapted to decide whether to trigger the intervention of the collision avoidance system at a current time instant (Tc) or to postpone said intervention decision at a later time instant (Tl) depending upon additional first and second information to be acquired between the current time instant (Tc) and the later time instant (Tl), wherein the means for intervention decision is adapted to:
• a) compute a first decision value depending upon said additional first and second information,
• b) compute a second decision value depending upon a probability to avoid a collision between the host vehicle and any other vehicle if the collision avoidance system is triggered at said later time instant (Tl),
• c) verify a first decision criterion depending on said first decision value and a second decision criterion depending on said second decision value. and
• d) decide to trigger the collision avoidance system at current time instant (Tc) or postponing the intervention decision based on the outcome of the verification,
• the intervention decision taking into account a first expected cost of decision based upon first and second information acquired up to current time instant (Tc) and a second expected decision cost computed using probabilities of said additional first and second information to be acquired between the current time instant (Tc) and the later time instant (Tl), to ensure that a postponement is likely to decrease the probability of unnecessary intervention.