Autonomous driving method and device for a motorized land vehicle

An autonomous driving method for controlling the speed of a motorized land vehicle, called an ego-vehicle, by adaptive speed regulation based on a target speed, the ego-vehicle comprising:

• internal sensing means for electronically measuring or estimating dynamics of the ego-vehicle,
• external sensing means for perceiving an environment of the ego-vehicle, and
• an autonomous driving computer adapted to regulate the speed of the ego-vehicle based on a target speed;
• said autonomous driving computer being in communication with said internal sensing means and said external sensing means to receive information from said internal sensing means and external sensing means;
• said autonomous driving computer regulating a speed of the ego-vehicle in response to output received from said internal sensing means and external sensing means;
• the method comprising the steps of:
• said autonomous driving computer receiving information from said external sensing means indicative of the presence of a first target vehicle;
• said autonomous driving computer electronically determining movement information of the first target vehicle based on said information from said external sensing means;
• said autonomous driving computer receiving information from said internal sensing means regarding dynamics of the ego-vehicle and electronically determining a speed of the ego-vehicle based on said information from said internal sensing means;
• said autonomous driving computer calculating a first relevance indicator for the first target vehicle, the relevance indicator being indicative of a probability of presence of the first target vehicle in front of said ego-vehicle;
• wherein when said autonomous driving computer based on the first relevance indicator determines a loss of detection of the first target vehicle,
• when the first relevance indicator is greater than a predetermined deselection value, said autonomous driving computer calculates an autonomous driving setpoint as a function of the movement information of the first target vehicle, the target speed of the ego-vehicle, and the speed of the ego-vehicle;
• said autonomous driving computer updating the first relevance indicator from a time passed since the last detection of the first vehicle;
• and
• when the relevance indicator is greater than the predetermined deselection value, said autonomous driving computer calculating an autonomous driving setpoint as a function of the movement information of the target vehicle, the target speed of the ego-vehicle, and the speed of the ego-vehicle;
• and
• wherein when said autonomous driving computer, based on information received from said external sensing means, determines the presence of a second target vehicle, said method includes:
• said autonomous driving computer determining movement information of said second target vehicle based on information received from said external sensing means;
• said autonomous driving computer calculating a second relevance indicator for the second target vehicle, said second relevance indicator being indicative of a probability of a presence of the second target vehicle;
• said autonomous driving computer determining a distance between the ego-vehicle and the second target vehicle, said autonomous driving computer determining a distance between the ego-vehicle and the first target vehicle, and
• when the second relevance indicator for the second target vehicle is greater than a predetermined selection value and when the distance between the ego-vehicle and the second target vehicle is smaller than the distance between the ego-vehicle and the first target vehicle, said autonomous driving computer calculating an autonomous driving setpoint based on the movement information of the second target vehicle, the target speed and the speed of the ego-vehicle, and
• regulating the ego vehicle's speed by controlling acceleration or deceleration of the ego-vehicle based on the calculated autonomous driving setpoint.