JP3168820B2 - Vehicle acceleration sensor correction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular acceleration sensor correction device, and more particularly to a vehicular acceleration sensor correction device for correcting a drift of a zero point due to a temporal change of an acceleration sensor when the vehicle is stopped without acceleration. About.

[0002]

2. Description of the Related Art Conventionally, there has been known an apparatus which corrects a zero-point drift due to a temporal change of an acceleration sensor mounted on a vehicle to prevent a decrease in accuracy of acceleration detection due to a temporal change. For example, Japanese Patent Application Laid-Open No. 2-19771 discloses an apparatus that detects an output value of an acceleration sensor when a vehicle stops and determines a correction amount so that the output value becomes zero to perform a correction process. Is disclosed.

When the vehicle is at a standstill, acceleration in the front-rear and left-right directions does not occur with respect to the vehicle, and these accelerations naturally do not act on the acceleration sensor mounted on the vehicle. The output of the sensor focuses on what should originally be zero.

Therefore, in a vehicle equipped with the correction device disclosed in the above publication, the output characteristic of the acceleration sensor is calibrated each time the vehicle stops, and the output characteristic is excellent without being affected by zero point drift due to aging. It is possible to maintain excellent output characteristics.

[0005]

However, the stopping road surface of the vehicle is not always flat, and the vehicle may be stopped on an inclined road. In this case, the gravitational acceleration acts not only in the direction perpendicular to the vehicle but also in the front-rear, left-right directions, and the acceleration sensor moves in the front-rear or left-right direction despite the vehicle being stopped. A state where acceleration is applied is formed.

[0006] On the other hand, the above-mentioned conventional apparatus is configured on the assumption that a zero output is obtained from the acceleration sensor when the vehicle stops, as described above. In some cases, erroneous correction is performed even though the acceleration sensor outputs an accurate output corresponding to the inclination.

[0007] The above-mentioned adverse effect caused by performing the correction of the acceleration sensor when the vehicle is stopped is determined, for example, by using a navigation system or the like to determine whether or not the stopped road surface is a sloping road. The correction can be removed even if it is prohibited, but in order to realize such a function, an expensive and complicated configuration is required, and the cost is greatly increased.

The present invention has been made in view of the above points, and when the output value of the acceleration sensor when the vehicle stops is equal to or less than a predetermined value, it is determined that the vehicle has stopped on a flat road. When the zero value of the acceleration sensor is corrected and the output value exceeding the predetermined value is output, it is determined that the vehicle has stopped on the slope and the zero point correction is not performed.
An object of the present invention is to provide a vehicle acceleration sensor correction device that solves the above-mentioned problems.

[0009]

FIG. 1 is a block diagram showing the principle of a vehicular acceleration sensor correcting apparatus for achieving the above object. That is, as shown in FIG. 1, the above-mentioned object is achieved when the acceleration execution condition
Correction amount determining means M2 for determining a correction amount necessary for zero-correcting the output of the vehicle, vehicle stop detecting means M3 for detecting stop of the vehicle, and the acceleration sensor M when the vehicle stops.
The vehicle stoppage is detected by the inclination determination means M4 for determining whether the output value of the acceleration sensor M1 exceeds a predetermined value and the vehicle stop detection means M3, and the output value of the acceleration sensor M1 is determined by the inclination determination means M4. When it is determined that the value does not exceed the value, the correction condition determining means M5 for determining whether the correction execution condition is satisfied, and the acceleration control when the vehicle is stopped.
An output value exceeding a predetermined value is detected from the
The difference between the output value during the first stop and the output value during the current stop is the predetermined value.
When the following condition continues, the acceleration sensor M
This is achieved by a vehicle acceleration sensor correction device including an abnormality determination unit M6 for determining the first abnormality .

[0010]

Further, in the vehicle acceleration sensor correction device having the above-described structure, there is provided traffic congestion determining means M7 for determining that the vehicle is traveling on a congested road, and the abnormality determining means M6 is provided.
The vehicle acceleration sensor that determines that the abnormality of the acceleration sensor M1 is not performed when the traffic congestion determination unit M7 determines that the vehicle is traveling in congestion is also effective.

[0012]

In the first aspect of the vehicle acceleration sensor correction device according to the present invention, the acceleration sensor M1 generates an output value according to the inclination of the stopped road surface when the vehicle is stopped, as long as the acceleration sensor M1 functions normally. When the vehicle stops on an inclined road, a relatively large output value is output, and when the vehicle stops on a flat road, a relatively small output value is output including a drift due to aging.

Therefore, when an output value exceeding a predetermined value is output from the acceleration sensor M1 when the vehicle stops, it can be determined that the vehicle has stopped on an inclined road irrespective of the presence or absence of drift due to aging. If the output value is less than the predetermined value, it can be determined that the vehicle has stopped on a substantially flat road surface.

On the other hand, the change over time in the output characteristic of the acceleration sensor M1 is a change that occurs relatively slowly, and the zero point output does not suddenly show a large change. Therefore, the drift amount due to the temporal change of the acceleration sensor M1 can be sufficiently corrected by a relatively small correction.

On the other hand, the correction condition determining means M5
Means that the correction execution condition is satisfied only when the vehicle stop is determined by the vehicle stop determination means M3 and the output value exceeding a predetermined value is not output from the acceleration sensor M1 by the inclination determination means M4. judge.

Therefore, the correction amount necessary for the zero point correction of the acceleration sensor M1 is determined by the correction amount determining means M2 only when the vehicle is stopped on a substantially flat road surface. become. Therefore, the determined correction amount is a value that is sufficient to correct the temporal change of the acceleration sensor M1 and that is not affected by the inclination of the stopped road surface.

In the second aspect of the vehicle acceleration sensor according to the present invention, the abnormality determining means M6 receives the supply of the output value exceeding the predetermined value from the acceleration sensor 1 when the vehicle is stopped. This is a case where the vehicle is stopped on a steep road surface or a case where an abnormality has occurred in the acceleration sensor M6.

The road gradient is generally changing,
When the vehicle repeatedly stops running, it is practically rare that the gradient of the stopped road surface is repeatedly detected as substantially the same value.

Therefore, when the abnormality determination means M6 continuously receives an output value that does not greatly differ between the previous stop and the current stop, it is possible to determine that an abnormality has occurred in the acceleration sensor M1. Therefore, in this embodiment,
The abnormality determination means M6 implements highly accurate abnormality determination for the acceleration sensor.

Further, in the third aspect of the vehicle acceleration sensor according to the present invention, when the traffic congestion judging means M7 judges that the vehicle is traveling in congestion, the abnormality judging means M6 sets the acceleration The abnormality determination of the sensor M1 is not performed.

That is, during the traffic congestion, the traveling stop is repeated while traveling a relatively short distance. For this reason, at the time of traffic congestion on an inclined road, almost the same output value is repeatedly supplied from the acceleration sensor M1 to the abnormality determination means M6 every time the vehicle stops, and the vehicle acceleration sensor correction device according to the second aspect described above. According to the above, an abnormality determination can be made even though the acceleration sensor M1 is normal.

On the other hand, in the vehicle acceleration sensor correction device according to the present embodiment, the abnormality determination is not performed in such a situation.
There is no erroneous detection of an abnormal state of the acceleration sensor M1.

[0023]

2 and 3 show a vehicle drive recorder 1 incorporating a vehicle acceleration sensor correction device according to the present invention.
FIG. 1 is an overall configuration diagram of an embodiment of the present invention, showing a functional block configuration diagram and a hardware block configuration diagram, respectively. Hereinafter, the configuration of the drive recorder 10 will be described with reference to these.

The drive recorder 10 is a device that receives various vehicle data from the sensors 20 mounted on the vehicle and records various vehicle data before and after the occurrence of an accident when the vehicle has an accident. Here, in the drive recorder 10 of the present embodiment, as each sensor 20, FIG.
The in-vehicle sensor shown in FIG.

Here, the longitudinal G sensor 21 is a sensor for detecting longitudinal acceleration acting on a vehicle on which the drive recorder 10 is mounted, and accurately detects acceleration in a normal area generated in a normal running state. .

The lateral G sensor 22 is a sensor for detecting the lateral acceleration acting on the vehicle, and similarly to the front and rear G sensor 21, accurately detects the acceleration in the normal area.
The drive recorder 10 records the output values of the front and rear G sensor 21 and the lateral G sensor 22 for the purpose of estimating the vehicle behavior before and after the occurrence of the accident.

Further, the collision sensor 23 is a sensor for detecting a large acceleration which occurs only when a vehicle has a collision accident or the like. The reason why the drive recorder 10 records the output value is to enable highly accurate identification of the time of occurrence of the collision accident.

The front-rear G sensor 21, the lateral G sensor 22, and the collision sensor 23 correspond to the acceleration sensor M1 in the present embodiment (hereinafter, when these are collectively referred to as acceleration sensors 21 to 23). The output value is to be corrected by the drive recorder 10 as described later.

The vehicle speed sensor 24 is disposed, for example, on a drive shaft of the vehicle, and generates a pulse signal at a cycle corresponding to the vehicle speed. The brake sensor 25 detects the brake depression force, and the accelerator sensor 26 detects the accelerator opening. Are sensors that respectively detect. The yaw rate sensor 27 is a sensor that detects the rotational speed of the vehicle about the center of gravity axis, that is, the turning angular speed of the vehicle.

The vehicle speed sensor 24 and the brake sensor 2
5, the accelerator sensor 26 and the yaw rate sensor 27 record their output values in the drive recorder 10 to enable highly accurate vehicle behavior analysis after an accident. In the present embodiment, the drive recorder 10 It also has a function of supplying basic data when making a stop determination.

The drive recorder 10 mainly includes a CPU 11, a ROM 12, a RAM 13, and a backup RAM.
(B-RAM) 14, input port 15, output port 16
Are connected by a common bus 17. In addition, BR
The AM 14 is a nonvolatile data recording medium whose recorded contents are not erased even when the power supply is cut off.

Here, the input port 15 is a device that converts the output signal of each of the sensors 20 described above into a state that can be processed in the drive recorder 10 and takes in the output signal. The output port 16 is a predetermined device in the drive recorder 10. Is a device that outputs an abnormality signal to turn on the indicator lamp 30 when an abnormality determination described later is made as a result of the execution of the process.

The CPU 11 is a device that executes processing according to a program stored in the ROM 12. The data correction device 10a, the vehicle stop determination device 10b, and the correction amount calculation device 10c shown in FIG. 2 are realized by the CPU 11 executing a process described later.
The recording medium 1 shown in FIG.
0d will be realized.

That is, the drive recorder 1 of this embodiment
When 0 is functionally represented, it can be represented as a data correction device 10a, a vehicle stop determination calculation device 10b, a correction amount calculation device 10c, and a recording medium 10d as shown in FIG. Hereinafter, the function of each block will be described.

The data correction device 10a is a block for controlling data recording in the drive recorder 10.
In a normal state, all data supplied from each sensor 20 and correction amount data supplied from a correction amount calculation device 10c described later are supplied to the recording medium 10d together.

The occurrence of a vehicle accident is monitored based on the sensor output of the collision sensor 23 and the like. If an accident is detected, a predetermined recording stop control is performed to wait for a predetermined time after the occurrence of the accident. New writing of vehicle data to the recording medium 10d.

As a result, vehicle data for a predetermined period according to the memory capacity is recorded and retained in the recording medium 10d before and after the occurrence of a vehicle accident, and data effective for later accident analysis can be stored. It is planned.

The vehicle stop determination arithmetic unit 10b detects that the vehicle is in a stopped state based on data necessary for the stop determination such as the output of the vehicle speed sensor 24 among the data output from the sensors 20, The detection result is supplied to the correction amount calculation device 10c.

The correction amount calculating device 10c reads the data to be corrected in this embodiment of the sensors 20, that is, the data of the acceleration sensors 21 to 23 described above, and the vehicle stop determination calculating device 10b stops the vehicle. Upon detection, a correction amount required for zero point correction of each of these acceleration sensors is calculated and supplied to the data correction device 10a.

The reason why the zero point correction is performed for the acceleration sensors 21 to 23 is to correct the drift of the zero point due to a change with time due to the configuration of the acceleration sensors 21 to 23, which is difficult to prevent. It is not of a nature with sudden changes, but the changes always appear slowly.

Therefore, when the zero point outputs of the acceleration sensors 21 to 23 change abruptly and significantly, it can be determined that an abnormality which does not change with time has occurred in the acceleration sensor 20.

Therefore, in the present embodiment, the data correction device 1 which receives the supply of the correction amount from the correction amount calculation device 10c.
0a, when a rapid and large change in the correction amount is detected, the abnormality of the acceleration sensors 21 to 23 is determined, and the data correction device 10a uses the indicator lamp 30.
Lighting control is performed.

Hereinafter, the specific contents of the zero point correction function of the acceleration sensors 21 to 23 and the abnormality determination function of the acceleration sensors 21 to 23, which are characteristic operations of the drive recorder 10, will be described.

FIG. 4 is a flowchart showing an example of a routine executed by the CPU 11 to perform the above functions.

When this routine is started, first, in step 1
At 00, data is input from each sensor 20 described above. When the data input is completed for all the sensors 21 to 27, the process proceeds to step 102.

In step 102, it is determined whether or not the vehicle is stopped based on the input data. Here, in the present embodiment, vehicle speed = 0 km / hr, brake depression force ≧ 5 kgf, accelerator opening degree ≦ 3%, front and rear G (absolute value) ≦
If all of 0.15G, lateral G (absolute value) ≦ 0.15G, and yaw rate (absolute value) ≦ 5 deg / sec are satisfied, it is determined that the vehicle is stopped. The reason why the vehicle stop is not determined only on the condition that the vehicle speed is equal to 0 km / hr is to prevent erroneous detection when the wheels are locked.

Here, this routine is a routine executed to correct the zero point of the acceleration sensor while the vehicle is stopped. If it is determined in step 102 that the vehicle is not stopped, any processing is performed thereafter. This process is terminated without any processing, and the process proceeds to step 104 only when it is determined that the vehicle is stopped.

In step 104, the acceleration sensors 21 to
The output value of the sensor 23 is measured as a correction amount required for zero point correction of the front and rear G sensor 21, the lateral G sensor 22, and the collision sensor 23, respectively.

This step 104 is executed when the vehicle does not generate acceleration in the front-rear direction and in the lateral direction when the vehicle is stopped, as long as the stop surface is not a slope and the acceleration sensors 21 to 23 are normal. Should be essentially zero output from the acceleration sensors 21 to 23,
This is because, if any value is output, the value is considered to be caused by the drift of the zero point with the lapse of time.

After the output values of the acceleration sensors 21 to 23 have been measured as correction amounts in this manner, the process proceeds to step 106.
To calculate the inclination angle corresponding to the output value, assuming that the output values are caused by the inclination of the stopped road surface. In the following step 108, it is determined whether the inclination angle is larger than a predetermined determination value. Is determined.

As a result, when it is determined that the inclination angle is small, that is, when it is determined that the output values of the acceleration sensors 21 to 23 are near zero output, it is determined that the vehicle is stopped on a substantially flat road surface. Judgment proceeds to step 110, where the above output value is recorded as a correction amount, and thereafter, at step 124, the count number described later is reset, and the current process is terminated.

Therefore, when this routine is executed by the CPU 11, the correction amount required for the zero point correction is newly updated every time the vehicle stops on a flat road, and the RAM 1
3, the correction amount corresponding to the latest state of the acceleration sensors 21 to 23 is always recorded.

On the other hand, if it is determined in step 108 that the inclination angle converted from the output value exceeds a predetermined determination value, the process proceeds to step 112 without recording the output value as a correction value. After that, the acceleration sensor 21
23 are executed.

The inclination angle exceeds the predetermined judgment value when the vehicle is stopped on a relatively steep slope or when the acceleration sensors 21 to 23 themselves are abnormal. In such a case, the output is the acceleration sensor 21 to 23.
It is not a value issued as a zero point output from.

As a result, the amount of correction recorded in the RAM 13 is updated only when the output values of the acceleration sensors 21 to 23 when the vehicle stops are relatively small. It is possible to eliminate the influence of the inclination of the stopped road surface on the 23 zero-point correction amounts.

The zero point drift of the acceleration sensors 21 to 23 is a change that occurs within a relatively narrow range. Even when the execution condition of the zero point correction is set as described above, a sufficiently effective correction can be performed. This is as described above.

In step 112, the difference between the tilt angle calculated when the routine was last executed and the tilt angle calculated by the current execution is calculated. Then, in a step 114, it is determined whether or not the difference is smaller than a predetermined determination value.

As a result, if it is determined that the difference is not small, the acceleration sensors 21 to 23 change the output value in accordance with the change in the inclination of the road surface.
1 to 23 determine that they are functioning normally, and thereafter execute the processing of step 124 to end the current processing.

On the other hand, if it is determined in step 114 that the difference between the previous output and the current output is small,
Proceeding to 16, a process for incrementing the counter n is performed. When the vehicle is stopped and the process after step 104 is performed, the counter n determines that the inclination is “large” in step 108 and that the difference is “small” in step 114. It is a counter that counts the number of continuous situations.

Accordingly, the counted number corresponds to the number of continuous repetitions in which the output values exceeding a predetermined value and hardly changing are output from the acceleration sensors 21 to 23 when the vehicle is stopped.

After the counter n has been incremented in this way, the routine proceeds to step 118, where it is determined whether or not the count is 10 or more. If the count has not reached 10 yet, the current process is terminated without any further processing, and the process proceeds to step 120 after waiting for the count to reach 10.

Since the inclination angle of the traveling road is generally not constant, it is extremely unlikely that the road surface inclination at the time of stopping will be substantially the same for 10 consecutive times when the vehicle repeats traveling and stopping. In a rare case, such a situation is likely to be caused by an abnormality in the acceleration sensors 21 to 23.

Therefore, in this embodiment, when the condition of step 118 is satisfied, it is determined in step 120 that the acceleration sensors 21 to 23 are abnormal, and the output values are recorded in the B-RAM 14 which is a nonvolatile recording medium. Then, a process of turning on the indicator lamp 30 is performed in the subsequent step 122, and then the count is reset in a step 124 to end the process.

As a result, the drive recorder 1 of this embodiment
According to 0, when an abnormality occurs in the acceleration sensors 21 to 23 and a large output is continuously generated, the situation is promptly detected as an abnormality and recorded as vehicle data. Therefore, when performing an accident analysis based on the recorded data after the occurrence of the accident, it is possible to effectively prevent erroneous analysis due to the abnormality of the acceleration sensors 21 to 23.

In this embodiment, the abnormality of the acceleration sensors 21 to 23 is determined when the count number of the counter n reaches 10, as described above. However, the abnormality determination value is limited to "10". Not the acceleration sensor 21
It is possible to arbitrarily set an appropriate judgment value for judging the abnormalities of to 23.

Here, in this embodiment, the above-mentioned step 102 is used for the above-mentioned vehicle stop determination means M3, the above-mentioned step 106 is used for the above-mentioned inclination determination means M4, and the above-mentioned step 108 is used for the above-mentioned correction condition determination means M5. The above step 110 is performed by the correction amount determining means M2, and the steps 112 to 118 are performed by the abnormality determining means M10.
Respectively.

The routine shown in FIG. 4 is configured to determine the abnormality when the acceleration sensors 21 to 23 repeatedly and continuously output a high output when the vehicle is stopped. When traveling in congested traffic, traveling / stopping may be repeated while traveling a relatively short distance, and the acceleration sensors 21 to 23 may be repeated.
May be satisfied even though is normal.

FIG. 5 shows a CPU for preventing such erroneous determination.
11 is a flowchart illustrating an example of a routine executed by the control unit 11; Hereinafter, an operation when the CPU 11 executes this routine will be described. In FIG. 5, steps for executing the same processes as those in FIG. 4 are denoted by the same reference numerals, and description thereof will be omitted.

That is, in the routine shown in FIG. 5, it is determined that the vehicle is stopped (step 102), and it is determined that the inclination angle at that time is larger than a predetermined determination value (step 10).
8) If it is determined that the difference between the previous inclination angle and the current inclination angle is small (step 114), step 20 is executed.
At 0, it is determined whether or not the vehicle is traveling in congested traffic. If the vehicle is traveling in congested traffic, steps 116 to 122 are jumped and step 124 is executed.

In this case, even if a substantially constant high output value is repeatedly output from the acceleration sensors 21 to 23 every time the vehicle stops during traffic congestion, the situation is not changed.
The abnormality determination of the acceleration sensors 21 to 23 can be realized with higher accuracy than when the CPU 11 executes the routine shown in FIG.

The congestion determination in step 200 can be performed based on the result of executing a congestion determination routine as shown in FIG. 6 as a subroutine, for example.

Here, when the congestion determination routine shown in FIG. 6 is started, first, in step 300, it is determined whether or not a braking operation is being performed by a brake operation determination. If the brake is not operating, the routine proceeds to step 302, where the running time timer is incremented. This is because the interval at which the braking operation is performed is counted and used as a basis for determining traffic congestion.

After finishing the process of step 302, the process proceeds to step 304, where a process for holding the peak value of the vehicle speed is performed, and the current process ends. This is to determine whether or not the vehicle is congested based on the maximum vehicle speed during traveling.

On the other hand, if it is determined in step 300 that the brake is being operated, step 306 is executed.
The output of the willing running time timer to it is determined whether a predetermined value T ₀ or more.

Here, if the timer output ≧ T ₀ holds, it can be determined that the interval between braking operations is sufficiently long and the vehicle is not traveling in congestion. The peak hold value of the vehicle speed is reset together, and a flag indicating that there is no congestion is set in step 310, and the process is terminated.

On the other hand, if it is determined in step 306 that the timer output ≧ T ₀ is not established, the process proceeds to step 312 to check whether the timer output = 0 is established. Here, when the timer output = 0 is established, it is determined that the brake operation has been continuously performed from the previous processing, and the current processing is ended without performing any processing thereafter.

On the other hand, it is determined that the timer output = 0 is not established in step 312 when the interval between the end of the previous brake operation and the current brake operation is less than T _0. In this case, in step 314, the peak hold value of the vehicle speed becomes 2
It is determined whether the speed is 0 km / hr or less.

If the value exceeds 20 km / hr, it can be determined that the vehicle is traveling at a relatively high speed although the braking operation has been repeated in a relatively short time. it can. Therefore, when such a determination is made, it is determined that there is no traffic congestion, and thereafter, the processing after step 308 is executed, and the processing ends.

On the other hand, if it is determined in step 314 that the peak hold value of the vehicle speed is equal to or less than 20 km / hr, the flow advances to step 316 to increment the traffic congestion counter m. Is 5 or more. The condition of step 314 is a condition that is likely to be satisfied during a traffic jam, and if this condition is repeatedly satisfied, it can be determined that there is a traffic jam.

If it is determined in step 318 that m ≧ 5 is not satisfied, the running time timer and the vehicle speed peak hold value are cleared in step 320, and the above processing is repeatedly executed. When it is determined that ≧ 5 is satisfied, the process proceeds to step 322, where a flag indicating that traffic is congested is set, and the process ends.

As described above, when the CPU 11 executes the above-described congestion determination routine, whether or not the vehicle is traveling on a congested road is surely reflected in the state of the flag indicating that fact. In FIG. 5, in step 200,
Based on the state of the flag, it is possible to accurately determine whether or not the vehicle is congested.

For this reason, the drive recorder 1 of this embodiment
0, when the processing of FIGS. 5 and 6 is executed,
As for the abnormality determination of the acceleration sensors 21 to 23, the erroneous determination during the traffic jam of the vehicle can be reliably prevented.

In this embodiment, the above-mentioned step 2
00 and the congestion determination routine shown in FIG. 6 correspond to the congestion determination means M7 described above.

In the above-described embodiment, the vehicle acceleration sensor correction device according to the present invention is
In this example, the output values of the acceleration sensors 21 to 23 and the correction amount required for zero point correction are stored in the RAM 13.
The actual data correction will be performed at the time of the accident analysis later.
The timing for correcting data based on the correction amount is not limited to this.

That is, the vehicle acceleration sensor correction device according to the present invention can be applied to a system for controlling the vehicle by using the output values of the acceleration sensors 21 to 23 in real time. By correcting the output values of the acceleration sensors 21 to 23 every time the correction amount required for the correction is calculated, high-accuracy detection accuracy of the acceleration can be secured.

[0086]

As described above, according to the first aspect of the present invention, a relatively large output value is output from the acceleration sensor.
In some cases, the output value is due to the road slope.
Or is due to an abnormality in the acceleration sensor
Can be accurately determined, and the output of the acceleration sensor
Output error superimposed on the value that cannot be compensated by zero correction
In such a case, the situation can be reliably detected as abnormal .

[0087]

[0088] Therefore, according to the vehicle acceleration sensor correcting apparatus according to the present invention, in addition to high-precision correction is not affected by over <br/> time change Te normal time odor of the acceleration sensor can be realized, the acceleration When an abnormality occurs in the sensor, it is possible to reliably detect that the output value is not credible.

Further, according to the second aspect of the present invention, similarly to the case where an abnormality occurs in the acceleration sensor, during a vehicle congestion in which a relatively large output value can be repeatedly generated continuously and stably, it is possible to prevent such a problem. No abnormality is determined. Therefore, according to the vehicle acceleration sensor correcting apparatus according to the present invention, it is possible to be more accurately determined an abnormal state of the acceleration sensor.

[Brief description of the drawings]

FIG. 1 is a principle configuration diagram of a vehicle acceleration sensor correction device according to the present invention.

FIG. 2 is a functional block diagram of one embodiment of a drive recorder incorporating the vehicle acceleration sensor correction device of the present invention.

FIG. 3 is a hardware block diagram of one embodiment of a drive recorder incorporating the vehicle acceleration sensor correction device of the present invention.

FIG. 4 is a flowchart illustrating an example of a routine performed by the drive recorder according to the embodiment;

FIG. 5 is a flowchart of another example of the routine executed by the drive recorder of the embodiment.

FIG. 6 is a flowchart illustrating an example of a traffic jam determination routine performed by the drive recorder according to the embodiment.

[Explanation of symbols]

 M1 acceleration sensor M2 correction amount determination means M3 vehicle stop determination means M4 inclination determination means M5 correction condition determination means M6 abnormality determination means M7 congestion determination means 10 drive recorder 21 front and rear G sensor 22 lateral G sensor 23 collision sensor 24 vehicle speed sensor 25 brake sensor 26 Accelerator sensor 27 Yaw rate sensor

Claims (2)

(57) [Claims] When the correction execution condition is satisfied, the vehicle is mounted on the vehicle.
Correction required to zero-correct the output of the accelerometer
Correction amount determining means for determining the amount; vehicle stop detecting means for detecting the stop of the vehicle; output value of the acceleration sensor when the vehicle stops is a predetermined value
Inclination determining means for determining whether or not the vehicle has stopped;detectionMeans that the vehicle has stopped,
The output value of the acceleration sensor is
When it is determined that the value does not exceed the predetermined value, the correction is executed.
Correction condition determining means for determining whether the condition is satisfied;, When the vehicle stops, a predetermined value is exceeded from the acceleration sensor.
Output value is detected, and the output value at the previous stop
The state where the difference from the output value at the time of stopping is less than the predetermined value continues.
Abnormality determination to determine abnormality of the acceleration sensor
Means,  Vehicle acceleration sensor correction device characterized by comprising:
Place. 2. The vehicle acceleration sensor correction device according to claim 1, wherein the congestion determination means determines that the vehicle is traveling on a congested road.
A step, and the abnormality determining means determines whether the vehicle
If it is determined that the vehicle is traveling in a suspended state, the acceleration
An acceleration sensor correction device for a vehicle , wherein the abnormality determination of the sensor is not performed .