Method for operating a seat recognition device and recognition device

Abstract

The invention relates to a method for operating a recognition device (10) for a seat (12) of a motor vehicle, wherein a child seat is recognized as being present on the seat (12) or an adult is recognized as being seated on the seat (12) by means of an electronic evaluation device (24) of the recognition device (10), the airbag device of the seat (12) is activated in dependence on the recognition result, and a relative variance (34) is determined from the ratio of the pressure variance of the pressure acting on the seat (12) to the acceleration variance of the motor vehicle acceleration during a motor vehicle movement, and the recognition and the activation of the airbag device are carried out in dependence on the relative variance (34), wherein a speed variance (30) of the motor vehicle speed (28) is determined by means of the electronic evaluation device (24), and it is determined whether the recognition is carried out in a motor vehicle movement in dependence on the determined speed variance (30). The invention also relates to a recognition device (10).

Description

Technical Field

[0001] This invention relates to a method for operating a motor vehicle seat recognition device. The invention also relates to a recognition device. Background Technology

[0002] Methods for identifying people in seats are known from existing technology. In particular, in this case, people in seats can be categorized as either children in child seats or adults, with adults specifically referring to those who can sit in the seat without the need for seat assistive devices. Furthermore, existing technology knows that, for example, airbag deactivation can be performed when a child seat is identified. This results in greater safety for children in child seats because airbag deployment is prevented if a child seat is identified. For this purpose, both static and dynamic methods are known from existing technology. In the static method, only the pressure acting on the seat is measured to determine whether a child seat is present. In the dynamic method, the vehicle's own motion, especially acceleration, is taken into account, thereby achieving better identification of child seats during driving.

[0003] US2003004628A1 describes a weight-based passenger characterization method that reliably distinguishes children and short adults from strapped-in child seats based on measured passenger weight variance and vehicle acceleration variance. Velocity variance and acceleration variance are used to determine a relative variance, or normalized variance, which compensates for the effects of vehicle operation on rough surfaces. If the normalized variance remains below a first threshold for a predetermined period, the passenger is characterized as being in a child seat; if the normalized variance remains above a second threshold for a predetermined period, the passenger is characterized as either a child or a short adult.

[0004] EP 1470968A1 includes a vehicle passenger identification system comprising at least one pressure sensor disposed beneath foam material of a vehicle seat, at least one temperature sensor, and an electronic control and / or evaluation unit connected to these sensors. A mechanism is provided for causing the temporal characteristics of the output signal of the temperature sensor—particularly in response to changes in ambient temperature—located at intervals from the pressure sensor or seat foam, to approximate the temporal characteristics of the temperature present within the pressure sensor or seat foam area. Summary of the Invention

[0005] The objective of this invention is to provide a method and an identification device that enable better identification or classification of people in a seat.

[0006] This task is accomplished by the method and identification device according to the invention. Advantageous embodiments are described in further technical descriptions.

[0007] One aspect of the invention relates to a method for operating a vehicle seat identification device, wherein an electronic computing device of the identification device is used to identify whether a child seat is in the seat or an adult is seated in the seat, and wherein an airbag device of the seat is activated based on the identification status, and wherein a relative variance is determined from the ratio of the pressure variance (varianz) acting on the seat to the acceleration variance of the vehicle during vehicle movement, and the identification is performed and the airbag device is activated based on the relative variance.

[0008] The regulations stipulate that the speed variance of a motor vehicle should be determined using an electronic computing device, and the determination of whether identification should be performed during the movement of the motor vehicle should be based on the determined speed variance.

[0009] This allows for a better identification or determination of whether it is a children's chair or an adult's chair.

[0010] This invention therefore addresses, in particular, the problem that the criteria for judging dynamic algorithms (in other words, the relative variance) may undesirably increase under highly dynamic / drastically changing driving conditions, for example, when a child seat is installed. Specifically, abrupt acceleration and deceleration, as well as successive acceleration and deceleration, should be considered dynamic driving conditions. This is done because, particularly in the z-direction of the vehicle, the pressure variance is detected to have a stronger influence relative to the acceleration variance.

[0011] To identify relevant conditions as clearly as possible, velocity variance analysis has proven advantageous. In this case, the calculation can be particularly parameterized, for example, regarding the number of velocity values ​​considered for variance calculation. Furthermore, filtering can be implemented, for example, using calculated values ​​via moving averages. If the velocity variance now exceeds a parameterized threshold, a corresponding response can be taken at least for the over-threshold period, for example, resetting the relative variance to an existing parameterized initial value. Additionally, hysteresis or similar functions can be implemented for stabilization, for example, extending the response over a parameterized period.

[0012] This has particular advantages, namely, the ability to identify corresponding acceleration changes in relevant situations such as rapid acceleration and deceleration. Such changes cannot be identified by a single assessment of the absolute pedal position, as is the case in existing technologies. False positives / misreports can occur in identification based on pedal position, for example. This situation would be identified during downhill driving with continuous hard braking. Furthermore, it would also be identified during uphill driving with continuous hard acceleration. Moreover, false negatives can be identified based on pedal position. For example, false negatives would be identified when acceleration changes are below an absolute threshold.

[0013] According to an advantageous implementation, if the speed is below a predetermined speed threshold, a current initial value for the relative variance is determined. In particular, this predetermined speed may, for example, be below 4 km / h. Then, the relative variance is determined accordingly, for example, using a so-called static algorithm that considers only the current pressure. This reliably generates an initial value for the relative variance, which is then dynamically determined based on the current initial value during the vehicle's movement, thereby enabling the corresponding human identification.

[0014] Advantageously, if the velocity variance exceeds a predetermined threshold, identification based on the currently determined relative variance is prohibited. This allows, for example, the prevention of false identifications during relevant conditions. Therefore, false identifications will not occur during, for example, rapid acceleration and changes in acceleration. Thus, better identification of people can be achieved throughout the entire travel range.

[0015] It also proves advantageous that if the velocity variance exceeds a threshold, the initial value of the relative variance is used. In other words, if the velocity variance exceeds the threshold, the initial value of the relative variance is used. Therefore, it is reset and re-determined. This provides a reliable algorithm for determining the person in the seat.

[0016] In another advantageous embodiment, the velocity variance is set based on filtering of velocity values ​​and / or based on the number of velocity values. Therefore, the determination of the velocity variance can be parameterized. Furthermore, these velocity values ​​can be pre-smoothed and taken into account in determining the velocity variance. Additionally, filtering can be implemented, for example, by calculating a moving average.

[0017] Another advantage is that the steering angle variance can be determined, and based on this determined variance, it can be used to determine whether identification should be performed during vehicle movement. This allows for further identification of corresponding driving conditions. The determination of the steering angle variance is particularly similar to the determination of the speed variance.

[0018] Advantageously, the control signals from the vehicle assistance system are also transmitted to the identification device, and the system determines whether occupant identification should be performed during vehicle movement based on the transmitted control signals. In particular, unstable / dynamic driving conditions can also be identified. For example, the anti-lock braking system (ABS) as an assistance system can transmit corresponding intervention as a control signal, thereby prohibiting occupant identification in such situations. Furthermore, requirements for triggering preventative safety systems can be adopted for this purpose. Additionally, the electronic stabilization program as an assistance system can also transmit corresponding intervention as a control signal to the identification device.

[0019] In another advantageous embodiment, the current pressure acting on the seat is measured using a pressure sensor in the seat, and the pressure variance is determined using an electronic computing device based on the measured pressure. For example, the pressure sensor can be placed in the pressure cushion of the seat. This achieves reliable determination of the pressure variance.

[0020] It also proves advantageous to deactivate the airbag system when a child seat is detected and to activate it when an adult is detected. Here, "adult" specifically refers to someone who does not require a booster seat. Adults can also be teenagers who do not require seat assist devices. Therefore, by deactivating airbags such as the passenger airbag, it is possible to prevent airbag deployment when a child seat is detected, thus preventing potential injury to the child inside the seat.

[0021] Another aspect of the invention relates to a recognition device for a motor vehicle seat for identifying whether a child seat is in the seat or an adult is seated in the seat, having at least one electronic computing device, wherein the recognition device is designed to perform the method according to the foregoing aspect. In particular, the method is performed by means of this recognition device.

[0022] Another aspect of the invention relates to a motor vehicle having an identification device according to the foregoing aspects. This motor vehicle is particularly designed as a passenger car. Attached Figure Description

[0023] Other advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and in conjunction with the figures. The features and combinations of features mentioned above in the specification, as well as the features and combinations of features mentioned below in the description of the drawings and / or shown individually in the figures, may be used not only in their respective specified combinations, but also in other combinations or individually, without departing from the scope of the invention, wherein:

[0024] Figure 1 A perspective schematic diagram showing an embodiment of the identification device;

[0025] Figure 2 A schematic graph showing the speed of a motor vehicle and the corresponding speed variance is provided.

[0026] Figure 3 A schematic graph illustrating one embodiment of the method is shown.

[0027] In the figures, identical or functionally identical components are labeled with the same reference numerals. Detailed Implementation

[0028] Figure 1A perspective view of an identification device 10 for a motor vehicle (not shown) is shown. The identification device 10 is particularly designed for a motor vehicle seat 12. The seat 12 particularly includes a backrest 14, a cover 16, a foam pad 18, and a pressure sensor 20. The pressure sensor 20 is particularly composed of at least one silicone / silicone-filled pad 22. Additionally, the identification device 10 has at least one electronic computing device 24 connected to pressure and temperature sensors. Furthermore, the seat 12 has a shock-absorbing base 26.

[0029] Figure 2 A schematic graph showing the speed 28 of the motor vehicle and the corresponding determined speed variance 30.

[0030] In the marked area, particularly in situation 32, a sudden braking action occurs. This is specifically represented by the decline in the speed curve. Here, situation 32 can also be identified as the peak in the speed variance curve.

[0031] In the method for operating the recognition device 10 for the motor vehicle seat 12, the electronic computing device 24 of the recognition device 12 is used to identify whether a child seat is located on the seat 12 or an adult is seated on the seat 12, and an airbag device (not shown) of the seat 12 is activated based on the identification status. The relative variance 34 is determined from the ratio of the pressure variance acting on the seat 12 to the acceleration variance of the motor vehicle during motor vehicle movement. Figure 3 ), and based on the relative variance 34, identification and activation of the airbag device are performed.

[0032] This document stipulates that: the speed variance 30 of the motor vehicle speed 28 is determined by means of electronic computing device 24, and whether identification is performed during the movement of the motor vehicle is determined based on the determined speed variance 30. Figure 2 In particular, it is shown that identification is prohibited within the range of relevant condition 32. Specifically, it can be specified that, for example, identification based on the currently determined relative variance 34 is prohibited if the value is higher than a predetermined threshold 36 used for velocity variance 30.

[0033] Furthermore, it can be specifically stipulated that the speed variance of 30 is set based on the filtering of speed values ​​and / or based on the number of speed values.

[0034] In particular, Figure 2Therefore, a single instance of abrupt braking is demonstrated. This behavior should be identified and subsequently prevented from being identified by the occupants. This is done in particular because the relative variance 34 may undesirably increase in cases of highly dynamic / drastically changing driving conditions such as abrupt braking. The context here is that the pressure variance (especially in the z-direction) is relatively more significantly affected compared to the acceleration variance. In particular, analysis of the speed variance 30 proves advantageous for identifying the relevant condition 32 as clearly as possible. This determination can be parameterized in this case, for example, regarding the number of speed values ​​considered when calculating the speed variance 30, especially the number of pre-smoothed speed values. Furthermore, filtering of the calculated values ​​can be achieved, for example, through moving averages. If the speed variance 30 exceeds a parameterizable threshold, especially threshold 36, a corresponding response can be taken at least for the period exceeding the threshold, for example, resetting the relative variance 34 to an existing parameterizable initial value. Additionally, a hysteresis function or similar function can be implemented for stabilization, for example, extending the response to a parameterizable period.

[0035] The method of the present invention can also be considered for stabilization when a static algorithm is implemented separately. Furthermore, the steering angle variance can be determined, and based on the determined steering angle variance, it can be determined whether occupant identification should be performed during vehicle movement. This allows for further identification of corresponding driving conditions. The determination of the steering angle variance is particularly similar to the determination of the speed variance. Similarly, control signals from the vehicle assistance system can be transmitted to the identification device 10, and based on the transmitted control signals, it can be determined whether occupant identification should be performed during vehicle movement. In particular, unstable / dynamic driving conditions can also be identified. For example, a corresponding intervention can be transmitted as a control signal by the anti-lock braking system (ABS) as an assistance system, in which case occupant identification is thus prohibited. Additionally, a requirement for triggering a preventative safety system can be used for this purpose. Furthermore, the electronic stabilization program as an assistance system can also transmit a corresponding intervention as a control signal to the identification device 10.

[0036] Figure 3 Another schematic graph showing the relative variance of 34 is shown. In particular, Figure 3 The diagram shows the filtered relative variance 38, the initial value 40 for the relative variance 34, the threshold 42 for identifying the child seat, and the threshold 44 for identifying people, especially adults. It is particularly important to identify adults seated in seat 12 during motor vehicle movement. The initial value 40 for the relative variance 34 is determined especially at speeds less than 4 km / h. Thus, at speeds greater than 4 km / h, a parameterizable initial value 40 is output. It is particularly shown here that if the relative variance 34 is higher than the threshold 44, the corresponding airbag device is activated. If the relative variance 34 is lower than the threshold 42, the airbag device is deactivated.

[0037] Determining the speed variance 30 is particularly similar to determining the pressure and acceleration variances at speeds greater than 4 km / h. This requires a corresponding variance range (e.g., using a filtering device) and appropriate pre-filtering. It is now stipulated that if the speed variance 30 exceeds the corresponding threshold 36, the relative variance 34 is reset to its initial value 40, specifically indicated by arrow 46. This establishes a safe state. The output of the speed variance 30 can here be performed in the form of a raw frame. For example, for a test-driving method, it might be meaningful to use direct output instead of relative pressure.

[0038] In summary, the present invention thus proposes that personnel identification and classification are improved by means of the pressure sensor 20 in the seat 12 such that a speed variance 30 exceeding a threshold 36 causes the corresponding signal to be unused or used as an exclusion in the current evaluation, and the parameters are initialized and reset to prevent erroneous evaluations during fluctuations in driving dynamics and to stabilize the determination algorithm. As a key feature of this method, it is specifically stipulated that if the speed variance 30 is higher than the threshold 36, the measurement value is excluded or ignored. This enables driving dynamic-related evaluation of personnel identification or classification, which is better and more stable than simply using, for example, pedal position. Therefore, if the speed variance 30 is higher than the threshold 36, the analysis and use of the speed variance 30 and the ignoring and resetting of the corresponding parameters occur.

[0039] List of reference numerals

[0040] 10 Identification Devices

[0041] 12 seats

[0042] 14 Backrest

[0043] 16 Cover

[0044] 18 Foam Pads

[0045] 20 Pressure Sensors

[0046] 22 Silicone Resin Filler Pad

[0047] 24 Electronic computing devices

[0048] 26 Shock-absorbing base

[0049] 28 Speed

[0050] 30. Velocity Variance

[0051] 32. Relevant Status

[0052] 34 Relative Variance

[0053] 36 Threshold

[0054] 38. Filtered relative variance

[0055] 40 Initial value

[0056] 42 Threshold

[0057] 44 Threshold

[0058] 46 arrows

Claims

1. A method for identifying a seat (12) of a motor vehicle, wherein, -The electronic computing device (24) of the identification device (10) is used to identify whether a child chair is located on the seat (12) or an adult is seated on the seat (12). -Based on the identification result, the airbag device of the seat (12) is activated, and - A relative variance (34) is determined from the ratio of the pressure variance acting on the seat (12) to the acceleration variance of the vehicle during vehicle movement, and the identification and activation of the airbag device are performed based on the relative variance (34). Its characteristics are, The electronic computing device (24) determines the speed variance (30) of the vehicle speed (28), and based on the determined speed variance (30), it is determined whether the identification is performed during the movement of the vehicle. In cases where the relative variance (34) is below a predetermined speed threshold, an actual initial value (40) is determined.

2. The method according to claim 1, characterized in that, If the value exceeds a predetermined threshold (36) of the velocity variance (30), identification based on the currently determined relative variance (34) is prohibited.

3. The method according to claim 2, characterized in that, If the value is higher than the threshold (36) of the velocity variance (30), then the initial value (40) of the relative variance (34) is used.

4. The method according to any one of claims 1 to 3, characterized in that, The velocity variance is set based on the filtering of velocity values ​​and / or based on the number of velocity values ​​(30).

5. The method according to any one of claims 1 to 3, characterized in that, Additionally, the steering angle variance is determined, and the determination of whether the identification is performed during vehicle movement is based on the determined steering angle variance.

6. The method according to any one of claims 1 to 3, characterized in that, Additionally, the control signal of the motor vehicle assistance system is transmitted to the identification device (10), and the identification is determined based on the transmitted control signal to determine whether the identification is performed during motor vehicle movement.

7. The method according to any one of claims 1 to 3, characterized in that, The pressure sensor (20) in the seat (12) is used to measure the current pressure acting on the seat (12), and the pressure variance is determined by the electronic computing device (24) based on the current measured pressure.

8. The method according to any one of claims 1 to 3, characterized in that, The airbag system is deactivated when a child chair is detected and activated when an adult is detected.

9. A recognition device (10) for a motor vehicle seat (12), the recognition device being used to identify whether a child seat or an adult is seated in the seat (12), and having at least one electronic computing device (24), wherein, The identification device (10) is designed to perform the method according to any one of claims 1 to 8.

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