Method and device for performing a collision avoidance maneuver
Disclosed is a method of executing a collision avoidance maneuver ahead of an object in the surroundings, with which the vehicle is on a collision course. To allow determining the avoiding path in a simplest possible fashion and, in particular, a simplest possible parameterization of the path, the avoiding path is given by a sigmoid (ƒ a o (x); ƒ a o /2 (x); ƒ 2a o (x)), the shape of which is defined by at least one parameter (a; B; c) that is determined depending on the speed of the motor vehicle or a desired maneuver width of the collision avoidance maneuver. Also disclosed is a device which is suitable for implementing the method.
1. A method for executing a collision avoidance maneuver of a motor vehicle, the method comprising:
detecting an object ( 104 ) in the surroundings of the vehicle ( 101 ) with which the motor vehicle ( 101 ) is on a collision course;
determining a path for the collision avoidance maneuver of the motor vehicle ( 101 ), wherein if the path is given by a sigmoid, the shape of which is determined by at least one parameter (B; a; c), with the parameter (B; a; c) being established dependent on at least one of a speed (v) of the motor vehicle and a desired maneuver width (D) of the collision avoidance maneuver;
determining a start point at which the collision avoidance maneuver is started depending on the path established; and
influencing a steering system of the motor vehicle ( 101 ) depending on the path established after the motor vehicle ( 101 ) has reached the start point, wherein in an avoiding maneuver to the left in the vehicle's longitudinal direction,
B
=
D
c
=
1
a
ln
(
D
y
tol
-
1
)
applies to the parameters, where D is the maneuver width of the collision avoidance maneuver and y tol designates a predetermined tolerance.
2. The method as claimed in claim 1 , wherein a parameter (a) determining a gradient of the sigmoid is determined depending additionally on a speed (v) of the motor vehicle ( 101 ) in such a fashion that a lateral acceleration (ay) of the motor vehicle ( 101 ) which occurs in the collision avoidance maneuver does not exceed a predetermined maximum value (ay, Max).
3. The method as claimed in claim 1 , wherein the parameter of the sigmoid determining the gradient of the sigmoid is determined depending on the speed (v) of the motor vehicle ( 101 ) in such a manner that a maximum lateral jerk (β) that occurs in the collision avoidance maneuver does not exceed a predetermined maximum value (β Max ).
4. The method as claimed in claim 1 , wherein the sigmoid is given by
y
(
x
)
=
B
1
+
exp
(
-
a
·
(
x
-
c
)
)
where y(x) is a lateral offset of the motor vehicle and x is the distance to be covered in a longitudinal direction in a system of coordinates ( 301 ), the origin of which is basically identical with the start point of the collision avoidance maneuver and the positive x-direction of which points in the vehicle's longitudinal direction that prevails at the start point, in which case a is the parameter determining the gradient of the sigmoid, and B and c are additional parameters determining the shape of the sigmoid.
5. The method as claimed in claim 1 , wherein the maneuver width (D) is found out depending on the width of the front of an object (F; F′) facing the motor vehicle ( 101 ).
6. The method as claimed in claim 1 , wherein the maneuver width(D) is determined in such a manner that the motor vehicle ( 101 ) is steered from a present lane into the middle of an adjacent lane in the collision avoidance maneuver.
7. A method for executing a collision avoidance maneuver of a motor vehicle, the method comprising:
detecting an object ( 104 ) in the surroundings of the vehicle ( 101 ) with which the motor vehicle ( 101 ) is on a collision course;
determining a path for the collision avoidance maneuver of the motor vehicle ( 101 ), wherein if the path is given by a sigmoid, the shape of which is determined by at least one parameter (B; a; c), with the parameter (B; a; c) being established dependent on at least one of a speed (v) of the motor vehicle and a desired maneuver width (D) of the collision avoidance maneuver;
determining a start point at which the collision avoidance maneuver is started depending on the path established; and
influencing a steering system of the motor vehicle ( 101 ) depending on the path established after the motor vehicle ( 101 ) has reached the start point, wherein an avoiding maneuver to the right in the vehicle's longitudinal direction,
B
=
-
D
c
=
1
a
ln
(
D
y
tol
-
1
)
applies to the parameters, where D designates the maneuver width of the collision avoidance maneuver and y tol is a predetermined tolerance.