JP5546003B2 - Driving control method for occupant protection device and occupant protection control device - Google Patents

Description

  The present invention relates to a driving control method for an occupant protection device typified by a so-called airbag device and an apparatus therefor, and more particularly to a method for reliably acquiring data useful for operation analysis after activation of the occupant protection device.

  In recent years, in an occupant protection control device that drives and controls an occupant protection device typified by an airbag device, from the viewpoint of further improving the reliability of the occupant protection device, a vehicle collides, for example, an airbag is deployed. In order to analyze the collision situation after the fact and contribute to the validity of the device operation and further improvement of the operation, the operation state data in the vehicle before and after the deployment and the electronic control unit of the control device etc. are non-volatile as the collision information Techniques for recording in a memory have been proposed and put into practical use (see, for example, Patent Document 1 and Patent Document 2).

JP 2000-512955 A (page 3-7, FIG. 1) JP 2002-37014 A (page 3-4, FIGS. 1 to 4)

However, writing data into the non-volatile memory takes time as compared with the case of RAM (Random Access Memory), and in some cases, it may take several seconds.
On the other hand, the electronic control unit used in the passenger protection control device is generally equipped with a backup power source in case the battery is damaged or the power line is disconnected in the event of a collision because of its required functions. Is.
This backup power supply enables the current supply necessary to ignite the inflator for deploying the airbag even when the power supply from the vehicle battery to the electronic control unit is cut off in the event of a collision. The operation of the protection device can be surely ensured.

  However, even if it is a backup power supply, the current supply is limited, and after a certain period of time, the operation of the electronic control unit by the backup power supply is also stopped. In such a case, the backup power supply is not necessarily in a state that allows sufficient current supply to ignite the inflator, and even if the inflator can be ignited and the airbag can be deployed, There is a possibility that all or part of the collision information cannot be recorded in the memory.

  The present invention has been made in view of the above circumstances, and it is possible to drive an occupant protection control device that can reliably acquire minimum data useful for subsequent analysis regardless of whether or not there is a margin of battery power. A control method and an occupant protection control device are provided.

In order to achieve the above object of the present invention, a driving control method for an occupant protection control device according to the present invention includes:
When it is determined that the occupant protection device needs to be activated, the battery state and the backup power supply voltage are recorded in a nonvolatile memory before the occupant protection device is activated.
In order to achieve the above object of the present invention, an occupant protection control device according to the present invention includes:
It has a control unit configured to diagnose the presence or absence of a vehicle collision and determine whether or not the occupant protection device needs to be activated based on the diagnosis result, and the control unit determines that the occupant protection device needs to be activated. An occupant protection control device configured to generate and output a signal for starting the occupant protection device,
The control unit determines whether or not the battery voltage exceeds a predetermined value until it is determined that the activation of the occupant protection device is necessary based on a diagnosis result of the presence or absence of a vehicle collision, and a backup When a power supply voltage is input and it is determined that the occupant protection device needs to be started, a signal for starting the occupant protection device is generated and output according to the determination result. The determination result and the backup power supply voltage are configured to be written in the nonvolatile memory.

  According to the present invention, unlike the conventional case, when the occupant protection device is activated, for example, specifically when it is determined that the occupant protection device needs to be activated, not when the squib is lit, that is, for example, the air When it is determined that the development of the back is necessary, the state of the battery voltage, the backup power supply voltage is written to the nonvolatile memory and recorded, so that the collision information by the conventional method is not recorded, By analyzing the status of the battery voltage recorded in the non-volatile memory and the backup power supply voltage, it is easier to identify the cause of the collision data not being recorded and the collision data is normal. Even when recorded, the consistency of the data can be supported by analysis of the state of the battery voltage recorded in the non-volatile memory and the backup power supply voltage. Becomes ability in which an effect that it is possible to contribute to improving the reliability of equipment.

It is a block diagram which shows the structural example of the passenger | crew protection control apparatus in embodiment of this invention. 2 is a flowchart showing an outline of a drive control process executed by a control unit constituting the occupant protection control device in the embodiment of the present invention shown in FIG. 1. It is a flowchart which shows the more detailed process sequence until it reaches ignition control of the drive control process of the passenger | crew protection control apparatus shown by FIG.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3.
The members and arrangements described below do not limit the present invention and can be variously modified within the scope of the gist of the present invention.
First, the configuration of an occupant protection control device (hereinafter referred to as “the present device”) according to an embodiment of the present invention will be described with reference to FIG.
The apparatus includes a control unit (indicated as “CPU” in FIG. 1) 1, an ignition circuit 2, a nonvolatile memory 3, a lamp drive circuit 4, a backup power supply 5, and a power supply circuit 6. It is configured as.

The control unit 1 has a storage element (not shown) such as a RAM and a ROM centered on, for example, a microcomputer (not shown) having a known and well-known configuration, and provides a failure diagnosis for the entire apparatus. Processing and drive control processing of an occupant protection device to be described later are executed.
The control unit 1 receives a detection signal from the acceleration sensor 9 and is used for a failure diagnosis process and a driving control process for an occupant protection device. Further, the opening / closing state of the ignition switch 10 is input to the control unit 1, and the operation of the control unit 1 is turned on / off in response to the opening / closing of the ignition switch 10. ing.

The ignition circuit 2 is a circuit for igniting the squibs 11a and 11b provided in the airbag devices 7A and 7B provided outside the apparatus, and the squibs 11a and 11b are responsive to a control signal from the control unit 1. It has a well-known and well-known configuration configured to perform an ignition operation.
The non-volatile memory 3 is for recording specific data to be described later. Specifically, for example, the non-volatile memory is formed by using an EEPROM or the like. Such a non-volatile memory 3 is capable of storing and holding data even when the power supply is cut off, as is well known.

The lamp driving circuit 4 is a circuit for turning on the alarm lamp 8 when it is determined as a specified failure state as a result of the failure diagnosis process for the present apparatus executed by the control unit 1.
The power supply circuit 6 stabilizes a battery voltage VB supplied from a vehicle battery (not shown) and supplies it to a necessary part of the apparatus, converts the battery voltage VB into another required voltage, It is to be supplied to the necessary part of the device.

  The backup power source 5 supplies power necessary for the operation of the apparatus when the external power supply to the apparatus is interrupted. Note that when the battery voltage VB is supplied from the outside in a normal operation state, the backup power supply 5 is in a so-called floating operation state in which the power supply circuit 6 receives power supply and enters an operation state.

FIG. 2 shows a flowchart of a schematic procedure of the drive control processing of the occupant protection control device executed by the control unit 1, and the contents thereof will be described with reference to FIG.
The driving control processing of the occupant protection control device is roughly divided into normal processing and interrupt processing. First, the normal processing is composed of basic processing procedures. In FIG. In particular, only processing related to the recording of collision information (collision data) is shown.

That is, the normal process is composed of a plurality of processes that are repeatedly executed at all times. Whether or not a recording request for the nonvolatile memory 3 has occurred after the execution of a plurality of processes not shown in FIG. Is determined (see step S102 in FIG. 2).
In step 102, it is determined that a recording request to the non-volatile memory 3 has occurred. In the interrupt processing described later, a collision data capturing process (see step S700 in FIG. 2) is executed and recording starts. This is when a request is generated.

Therefore, when it is determined in step S102 that a recording request for the nonvolatile memory 3 has occurred (in the case of YES), collision data is recorded in the nonvolatile memory 3 (step S104 in FIG. 2). Next, a series of normal processing starts from the beginning.
If it is determined in step S102 that a recording request for the volatile memory 3 has not occurred (NO), a series of normal processes is started from the beginning.

On the other hand, the interrupt process is executed at predetermined time intervals or every time a predetermined condition is established. In FIG. 2, the diagnosis process (see S200 in FIG. 2) and the subsequent steps. However, illustration of processes performed before that is omitted.
In the following, the interrupt process will be described. In the diagnosis process, it is determined whether or not the apparatus is in a normal operating state, and then the analog data required for the subsequent processes such as the collision diagnosis process. Is converted into digital data in the control unit 1 (step S300 in FIG. 2).

Next, a collision diagnosis process for diagnosing whether or not a collision that requires deployment of the airbag devices 7A and 7B has occurred is performed (see step S400 in FIG. 2).
Next, the state of the external power supply and the state of the backup power source 5 are monitored, and predetermined data relating to the power source is recorded in the nonvolatile memory 3 (details will be described later) (step S500 in FIG. 2). reference). Thereafter, when it is determined by the above-described collision diagnosis processing that ignition to the squibs 11a and 11b is necessary, necessary ignition control is executed (see step S600 in FIG. 2).

Then, a predetermined collision data fetch, that is, a request for writing and recording into the nonvolatile memory 3 is made (see step S700 in FIG. 2).
Here, conventionally, the collision data is, for example, data representing the operation state of the vehicle, the operation state of the control unit 1, and the data representing the operation state of another electronic control unit (not shown). However, it is not necessary to be limited to a specific type of data, and what data should be used as collision data should be appropriately selected according to the type of occupant protection device and the configuration of the control device. .
As described above, this recording request is taken over by the process of step S102 of the normal process, and in the determination of the presence / absence of the recording request in step S102, it is determined that there is a recording request.

Next, a more specific procedure of the process from step S300 to step S600 in the interrupt process described above will be described with reference to the flowchart shown in FIG.
First, in step S300, the battery voltage VB supplied to the apparatus from the outside and the output voltage of the backup power source 5 are each converted from analog to digital and stored in an appropriate storage area in the control unit 1. .

Next, collision diagnosis processing is performed as in the conventional case (see step S400 in FIG. 3).
Next, it is determined whether or not the battery voltage VB exceeds a predetermined OFF voltage (see step S502 in FIG. 3).
Here, the OFF voltage is a voltage at which normal operation of the present apparatus cannot be ensured, and specific values should be set based on specific specifications of individual apparatuses.

  If it is determined in step S502 that the battery voltage VB exceeds the predetermined OFF voltage (in the case of YES), the process proceeds to step S504, which will be described later, while the battery voltage VB has a predetermined OFF voltage. If it is determined that it has not exceeded (in the case of NO), it is determined that the present apparatus is not in a normally operable state, and the process proceeds to step S512 described below. In the embodiment of the present invention, when it is determined that the battery voltage VB does not exceed the predetermined OFF voltage (in the case of NO), an electric wire (not shown) connecting the vehicle battery and the apparatus (not shown) (Not shown) is disconnected, the process proceeds to step S512.

In step S512, the “battery state” is set to “OFF”.
Here, “battery state” is a flag name indicating whether or not the battery voltage VB exceeds the OFF voltage, and “OFF” means that the battery voltage VB does not exceed the OFF voltage. More specifically, in the case of “OFF”, for example, “battery state” is set to “0”.

Next, it is determined whether “OFF time measurement in progress” is “true” (see step S514 in FIG. 3).
Here, “OFF time measurement in progress” is a flag name indicating whether or not the OFF time is being measured, and “OFF time measurement in progress” is set to “true”. Means that has been done. More specifically, in the case of “true”, for example, “during OFF time measurement” is set to “1”.
Here, in the previous step S502, when it is determined that the battery voltage VB does not exceed the predetermined OFF voltage (in the case of NO), measurement of the time during which the state continues is started. The OFF time is the measured time.

If it is determined in step S514 that “OFF time measurement is in progress” is “true” (in the case of YES), that is, if it is determined that the OFF time measurement is currently being performed, “OFF time”. Is up, that is, time measurement is continued (see step S516 in FIG. 3), and the process proceeds to step S506 described later.
On the other hand, if it is determined in step S514 that “OFF time is being measured” is not “true” (NO), that is, if it is determined that the current OFF time is not measured, “OFF time” “Measurement in progress” is set to “true”, and the OFF time measurement is newly started (see step S518 in FIG. 3), and then the process proceeds to step S506 described later.

Next, in step S504, the “battery state” is assumed to be “normal”. Specifically, for example, “battery state” is set to “1” representing “normal”.
At the same time, “OFF time” is reset, and “OFF time measurement in progress” is set to “false”, that is, “0”, for example.

  Then, in the previous collision diagnosis process (see step S400 in FIG. 3), it is determined whether or not the airbag devices 7A and 7B are required to be deployed (see step S506 in FIG. 3). If it is determined that the determination has been made (development determination is present) (in the case of YES), the process proceeds to step S508 described below, whereas if it is determined that there is no expansion determination (in the case of NO), A series of processing is terminated.

In step S508, it is determined whether or not the ignition control is being performed, that is, whether or not the control operation for igniting the squibs 11a and 11b is being performed, and if it is determined that the control is being performed (if YES) ), The ignition control is continued (see step S600 in FIG. 3).
On the other hand, if it is determined in step S508 that the ignition control is not being performed (in the case of NO), the three data of “battery state”, “backup power supply voltage”, and “OFF time” at this time point are: Prior to ignition control, it is recorded in the nonvolatile memory 3 (see step 510 in FIG. 3), and thereafter ignition control is executed (see step S600 in FIG. 3).

As described above, the occupant protection control device according to the embodiment of the present invention is different from the conventional case. When it is determined that the airbag devices 7A and 7B need to be deployed, in other words, ignition control for the squibs 11a and 11b. Before the operation is executed, at least three data of “battery state”, “backup power supply voltage”, and “OFF time” are written to the non-volatile memory 3 and recorded and held. Therefore, it contributes to improving the reliability of the apparatus.
That is, when writing the collision data after ignition control to the nonvolatile memory 3 (see step S104 in FIG. 2), only a part of the scheduled collision data is normally recorded for some reason or all collisions are recorded. It is empirically known that a situation in which collision data is not normally recorded, such as data not being recorded, can occur.

On the other hand, since the three data of “battery state”, “backup power supply voltage”, and “OFF time” are written in the nonvolatile memory 3 at the timing described above, they are more normal than the collision data. The possibility of being recorded is extremely high.
And when these three data are normally recorded, by verifying these three data later, whether or not the cause of the recording of the collision data being normal is at least the backup power source 5, It is possible to determine whether or not the battery voltage is supplied from a vehicle battery (not shown), making it easier to analyze the cause of the fact that some or all of the collision data has not been recorded, and plan In the case where all the collision data being recorded is recorded, it is possible to confirm that the collision data is consistent by verifying the above-mentioned three data, which contributes to improving the reliability of the apparatus. It will be a thing.

  This is suitable for an occupant protection control device in which further improvement in reliability of collision data is desired.

DESCRIPTION OF SYMBOLS 1 ... Control part 2 ... Ignition circuit 3 ... Non-volatile memory 5 ... Backup power supply 7A, 7B ... Airbag apparatus 11a, 11b ... Squib

Claims (4)

A drive control method for an occupant protection control device for controlling the operation of an occupant protection device for protecting a vehicle occupant,
When it is determined that activation of the occupant protection device is necessary, before the occupant protection device is activated, a determination result of whether or not power supply to the occupant protection control device by the battery is normally performed , and by the battery the supply voltage of the backup power supply supplies power to the occupant protection control device in case the power supply to the passenger protection control device is not performed normally, the occupant protection control device, characterized in that recorded in the non-volatile memory Drive control method. The state of the battery indicates whether or not the power supply to the occupant protection control device by the battery is normally performed. When it is determined that the power supply to the occupant protection control device by the battery is cut off, the nonvolatile memory 2. The driving control method for an occupant protection control device according to claim 1, wherein an elapsed time until writing to the vehicle is measured and the measurement result is written to the nonvolatile memory. It has a control unit configured to diagnose the presence or absence of a vehicle collision and determine whether or not the occupant protection device needs to be activated based on the diagnosis result, and the control unit determines that the occupant protection device needs to be activated. An occupant protection control device configured to generate and output a signal for starting the occupant protection device,
Wherein, until it is determined that the start cornerstone of the occupant protection device based on the diagnosis result of the presence or absence of a vehicle collision, the occupant protection device the power supply voltage of a battery for supplying power to the occupant protection control device To a passenger protection control device in case the power supply to the passenger protection control device by the battery is not normally performed. When a power supply voltage of a backup power supply that supplies power is input and it is determined that the occupant protection device needs to be started, a signal for starting the occupant protection device is generated and output according to the determination result The occupant protection control device is configured to write the determination result of the battery voltage and the power supply voltage of the backup power source in a nonvolatile memory before. When it is determined that the battery voltage does not exceed the predetermined voltage, the control unit measures an elapsed time from the determination time, and when it is determined that the occupant protection device needs to be started, the determination is performed. Before the signal for starting the occupant protection device is generated and output according to the result, the measurement result of the elapsed time and the backup power supply voltage are configured to be written in a nonvolatile memory. The occupant protection control device according to claim 3.

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