Restraining system comprising a restraining device for protecting at least one passenger and a method for controlling a restraining system

• US 20030034194A1
• Filed: 07/31/2002
• Published: 02/20/2003
• Est. Priority Date: 08/29/2000
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Koehler, Armin, Roelleke, Michael, Jauch, Thomas
• Granted Patent: US 6,836,716 B2
• Time in Patent Office: Days
• US Class Current: 180/271
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over

Abstract

A restraint system having a restraint device for protecting at least one passenger and a method for controlling a restraint system are proposed, which act so as to transform using a wavelet transformation, a signal measured by an acceleration sensor into a frequency range and in order to determine from the transformed signal the optimal triggering time point for the restraint device. For this purpose, the wavelet-transformed signal, on the one hand, is used for determining features in order to determine a crash type, and, on the other hand, to determine the braking acceleration energy. If the braking acceleration energy lies above a preestablished threshold value and if the identified crash type requires a triggering of the restraint system, then the restraint system is triggered.

Claims

1. A restraint system having a restraint device for protecting at least one passenger, the restraint system having an acceleration sensor (1) for measuring an acceleration of the vehicle, an analog/digital converter (2) for converting an output signal of the acceleration sensor (1) into a digital signal corresponding to the acceleration, a processor (3) for carrying out a wavelet transformation of the digital signal into a frequency signal, a memory (4), and an actuator (5) for controlling the restraint device (6), wherein the processor (3) subdivides the frequency signal into individual frequency ranges, the processor (3), for each frequency range measures the specific maximum and the specific average signal energy in order to extract features;

the processor (3) determines a crash type on the basis of the features, the processor (3) determines from the frequency signal a measure for the braking acceleration energy; and

the processor (3), as a function of the measure and of the crash type, transmits a control signal to the actuator (5).

2. The restraint system as recited in claim 1,

wherein the processor (3) compares the extracted features to the features that are learned and stored in the memory (4), in order to determine the crash type, the learned features being subdivided into records, and crash types being assigned in each case to the records.

3. The restraint system as recited in claim 2,

wherein the processor (3) calculates differences between the extracted features and the records of the stored features, and, if the differences of one record lie beneath a first threshold value, the processor (3) assigns the extracted features to the crash type of this record.

4. The restraint system as recited in claim 3,

wherein the processor (3) compares the measure to a second threshold value that is changeable over time and, if the measure lies above the second threshold value, the processor (3) transmits to the actuator (5) a control signal as a function of the identified crash type.

5. A method for controlling a restraint system (6), the acceleration of a vehicle being measured as an acceleration signal, the acceleration signal being digitalized into a digital signal, the digital signal being transformed using a wavelet transformation into a frequency signal, the restraint system (6) being controlled by an actuator (5), wherein the frequency signal is subdivided into frequency ranges, the specific maximum and specific average signal energies are determined for each frequency range in order to extract features;

the crash type is determined on the basis of the features;

a measure for the braking acceleration energy is determined from the frequency signal; and

a control signal is transmitted to the actuator (5) as a function of the measure and of the crash type.

6. The method as recited in claim 5,

wherein the processor (3) compares the extracted features to the stored features in order to determine the crash type, the stored features being subdivided into records, and the specific crash types being assigned to the records.

7. The method as recited in claim 6,

wherein the processor (3) calculates differences between the extracted features and the records of the stored features, and, if the differences for one record lie below a first threshold value, the processor (3) assigns the extracted features to the crash type of this record.

8. The method as recited in claim 5, 6, or 7,

wherein the processor (3) compares the measure to a second threshold value, and if the measure lies above the second threshold value, the processor (3) transmits a triggering signal to the actuator (5).