Control device, and method for controlling protective device

1. A control apparatus of a passenger protection apparatus, comprising:

a first acceleration detection part for location at a front of a vehicle to detect a first acceleration in a longitudinal direction of the vehicle;

a second acceleration detection part for location at a center of the vehicle to detect a second acceleration in the longitudinal direction of the vehicle and a third acceleration in a width direction of the vehicle; and

a control part for determining a front face collision based on the first and second accelerations detected by the first acceleration detection part and the second acceleration detection part, respectively to activate the passenger protection apparatus,

wherein the control part comprises:

a speed calculation part for integrating the first and second accelerations to obtain a speed (ΔV);

a level calculation part for calculating a level of a front face collision based on the first acceleration and the second acceleration;

a ΔV offset calculation part for making an offset adjustment of ΔV obtained by integrating the third acceleration so as to attenuate ΔV of the third acceleration based on a head-on collision, in order to obtain ΔV offset ; and

a first determination part for determining a presence of an offset collision or diagonal collision based on the level of the front face collision and the ΔV offset ;

wherein the control part activates the passenger protection apparatus for protecting a side and head of a passenger including a side airbag and a curtain airbag, if it is determined using the first determination part that an offset collision or diagonal collision has occurred.

2. The control apparatus according to claim 1 , wherein the control part compares the ΔV offset with a threshold to determine the presence and direction of an offset collision or diagonal collision.

3. The control apparatus according to claim 2 , wherein the control part comprises either:

a threshold setting part for counting an elapsed time from a time point at which it is determined that the second acceleration is equal to or greater than a start threshold to set the threshold for determining the presence of an offset collision or diagonal collision using the first determination part or the second determination part in accordance with the elapsed time; or

a valid period setting part for setting a valid period of the threshold in accordance with the elapsed time.

4. The control apparatus according to claim 1 , wherein the control part comprises:

a first determination technique for determining the presence and direction of an offset collision or diagonal collision based on a ratio of the third acceleration to the second acceleration; and

second determination part for determining the presence of an offset collision or diagonal collision, using at least one second determination technique for determining the presence and direction of an offset collision or diagonal collision, based on a difference of ΔV based on the first acceleration detected by each first acceleration detection part, upon comprising the first acceleration detection part on both sides in the width direction at the front of the vehicle.

5. The control apparatus according to claim 1 , wherein the control part comprises a processing part for subjecting at least one of the first acceleration, the second acceleration, and the third acceleration to a low pass filter process.

6. The control apparatus according to claim 1 , wherein, based on the first acceleration, the second acceleration, the third acceleration, and ΔV obtained by integrating these accelerations, the level calculation part obtains a logical product of these to obtain the level of a front face collision.

7. A method for controlling a protection apparatus, comprising:

determining a level of a front face collision based on a first acceleration in a longitudinal direction of a vehicle detected by a first acceleration detection part disposed at the front of the vehicle, and a second acceleration in the longitudinal direction detected by a second acceleration detection part disposed at a center of the vehicle;

making an offset adjustment to a speed (ΔV) obtained by integrating a third acceleration in the width direction of the vehicle detected by the second acceleration detection part so as to attenuate ΔV of the third acceleration based on a head-on collision, in order to obtain ΔV offset ;

determining a presence of an offset collision or diagonal collision based on the level of the front face collision, and the ΔV offset ; and

activating the passenger protection apparatus for protecting the side and head of a passenger including a side airbag and a curtain airbag, if it is determined that an offset collision or diagonal collision has occurred.