Method and control unit for ascertaining a type of collision of a vehicle

1. A method for ascertaining a type of collision of a vehicle, comprising:

receiving, via a reception interface, a first acceleration information item, a second acceleration information item, a third acceleration information item, and a fourth acceleration information item, wherein the first acceleration information item represents an acceleration of the vehicle in a first direction, the second acceleration information item represents an acceleration of the vehicle in a second direction, the third acceleration information item represents an acceleration of the vehicle in a third direction, and the fourth acceleration information item represents an acceleration of the vehicle in a fourth direction, the first and third directions each having a main component in a vehicle longitudinal direction, and the second and fourth directions each having a main component in mutually opposite vehicle transverse directions;

determining a first resultant acceleration information item from the first acceleration information item and the second acceleration information item;

determining a second resultant acceleration information item from the third acceleration information item and the fourth acceleration information item;

combining the first resultant acceleration information item and the second resultant acceleration information item to obtain at least one evaluation information item;

ascertaining the collision type based on the at least one evaluation information item;

comparing a difference to a second predetermined threshold value; and

deploying a passenger restraint unit during the collision based on the comparison between the difference and the second predetermined threshold value,

wherein the difference is:

formed from the first resultant acceleration information item and the second resultant acceleration information item in the combining step; and

compared to at least a first predetermined threshold value to ascertain the collision type.

2. The method as recited in claim 1 , wherein starting points of the main components of the first direction and the second direction are offset with respect to one another in relation to the vehicle transverse direction.

3. The method as recited in claim 1 , wherein:

the first resultant acceleration information item is determined by vector addition of the first and second acceleration information items; and

the second resultant acceleration information item is determined by vector addition of the third and fourth acceleration information items.

4. The method as recited in claim 1 , further comprising:

weighting the first acceleration information item using a first weighting value to obtain a weighted first acceleration information item;

weighting the second acceleration information item using a second weighting value to obtain a weighted second acceleration information item;

weighting the third acceleration information item using a third weighting value to obtain a weighted third acceleration information item; and

weighting the fourth acceleration information item using a fourth weighting value to obtain a weighted fourth acceleration information item;

wherein the first resultant acceleration information item is determined from the weighted first acceleration information item and the weighted second acceleration information item, and the second resultant acceleration information item is determined from the weighted third acceleration information item and the weighted fourth acceleration information item.

5. The method as recited in claim 4 , wherein each of the first weighting value, the second weighting value, the third weighting value, and the fourth weighting value is set as a function of an orientation of acceleration sensors in the vehicle and as a function of a vehicle type.

6. The method as recited in claim 4 , further comprising:

integrating the first resultant acceleration information item;

integrating the second resultant acceleration information item, and

wherein the at least one evaluation information item is obtained by combining the integrated first resultant acceleration information item and the integrated second resultant acceleration information item.

7. The method as recited in claim 1 , wherein the collision type is ascertained as one of an angled collision, an offset collision, or a head-on collision.

8. The method as recited in claim 1 , further comprising: forming a sum from the first resultant acceleration information item and the second resultant acceleration information item in the combining step; and forming a quotient from the difference and the sum; wherein the quotient is compared to a further threshold value in order to at least one of (i) recognize the collision type and (ii) determine a side of the vehicle involved in the collision.

9. The method as recited in claim 1 , wherein each of the first acceleration information item, the second acceleration information item, the third acceleration information item, and the fourth acceleration information item is provided by an acceleration sensor mounted in the vehicle.

10. The method as recited in claim 1 , wherein the collision type is ascertained as one of a collision on a right side of the vehicle or a collision on a left side of the vehicle.

11. The method as recited in claim 1 , further comprising:

filtering, by at least one low pass filter, the first acceleration information item, the second acceleration information item, the third acceleration information item, and the fourth acceleration information item.

12. A control unit for ascertaining a type of collision of a vehicle, comprising:

means for receiving, via a reception interface, a first acceleration information item, a second acceleration information item, a third acceleration information item, and a fourth acceleration information item, wherein the first acceleration information item represents an acceleration of the vehicle in a first direction, the second acceleration information item represents an acceleration of the vehicle in a second direction, the third acceleration information item represents an acceleration of the vehicle in a third direction, and the fourth acceleration information item represents an acceleration of the vehicle in a fourth direction, the first and third directions each having a main component in a vehicle longitudinal direction, and the second and fourth directions each having a main component in mutually opposite vehicle transverse directions;

means for determining a first resultant acceleration information item from the first acceleration information item and the second acceleration information item;

means for determining a second resultant acceleration information item from the third acceleration information item and the fourth acceleration information item;

means for combining the first resultant acceleration information item and the second resultant acceleration information item to obtain at least one evaluation information item;

means for ascertaining the collision type based on the at least one evaluation information item;

means for comparing a difference to a second predetermined threshold value; and

means for deploying a passenger restraint unit during the collision based on the comparison between the difference and the second predetermined threshold value,

wherein the difference is:

formed from the first resultant acceleration information item and the second resultant acceleration information item in the means for combining step, and

compared to at least a first predetermined threshold value to ascertain the collision type.

13. A non-transitory computer-readable data storage medium storing a computer program having program codes which, when executed on a computer, performs a method for ascertaining a type of collision of a vehicle, the method comprising:

receiving, via a reception interface, a first acceleration information item, a second acceleration information item, a third acceleration information item, and a fourth acceleration information item, wherein the first acceleration information item represents an acceleration of the vehicle in a first direction, the second acceleration information item represents an acceleration of the vehicle in a second direction, the third acceleration information item represents an acceleration of the vehicle in a third direction, and the fourth acceleration information item represents an acceleration of the vehicle in a fourth direction, the first and third directions each having a main component in a vehicle longitudinal direction, and the second and fourth directions each having a main component in mutually opposite vehicle transverse directions;

determining a first resultant acceleration information item from the first acceleration information item and the second acceleration information item;

determining a second resultant acceleration information item from the third acceleration information item and the fourth acceleration information item;

combining the first resultant acceleration information item and the second resultant acceleration information item to obtain at least one evaluation information item;

ascertaining the collision type based on the at least one evaluation information item;

comparing a difference to a second predetermined threshold value; and

deploying a passenger restraint unit during the collision based on the comparison between the difference and the second predetermined threshold value,

wherein the difference is:

formed from the first resultant acceleration information item and the second resultant acceleration information item in the means for combining step, and

compared to at least a first predetermined threshold value to ascertain the collision type.