JP2012234303A - Consciousness deterioration determining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a consciousness deterioration determining device scarcely causing a non-detection and an erroneous detection when determining a consciousness deterioration of a driver while suppressing a data amount.SOLUTION: The consciousness deterioration determining device 1 according to the present invention includes: a normal steering quantity calculating section 51 for calculating, as a normal steering quantity, steering data with a steering angular speed of equal to or more than a first predetermined value and equal to or less than a second predetermined value, in a normal driving of a driver; a steering deviation degree calculating section 55 for calculating a deviation degree of the steering quantity of the driver from the normal steering quantity; a steering deviation degree determining section 56 for determining whether or not a steering deviation degree is a predetermined value or more; and a consciousness deterioration determining section 57 for determining that the driver is in the consciousness deteriorated state when the steering deviation degree is a predetermined value or more. This device 1 calculates the normal steering amount with the steering data limited to that having the steering angular speed of equal to or more than the first predetermined value and equal to or less than the second predetermined value so as to scarcely cause the non-detection and erroneous detection when determining the consciousness deterioration, while suppressing the data amount.

Description

  The present invention relates to a consciousness decrease determination device that determines a consciousness decrease state of a driver of a vehicle.

  2. Description of the Related Art Conventionally, as a technique for determining a state of consciousness reduction of a driver of a vehicle, an apparatus that issues an alarm when a traveling lane is likely to deviate is disclosed (see Patent Document 1). In the device of Patent Document 1, the warning is prohibited when the driver's arousal level is high, and the vehicle is moving away from the driving lane even though the driver is not operating the steering wheel. Judge that there is a high need for departure warning.

Japanese Patent Laid-Open No. 11-34773

  By the way, as a technique for determining the state of consciousness reduction of the driver of the vehicle, an apparatus for determining whether or not the current steering state is more than a predetermined distance compared to the normal steering state is also conceivable. In this device, it is conceivable to reduce the steering data from the viewpoint of suppressing the amount of data to be calculated. However, if appropriate steering data cannot be acquired, there is a possibility that the consciousness deterioration determination is not detected or erroneously detected.

  Accordingly, an object of the present invention is to provide a consciousness deterioration determination device that performs a consciousness decrease determination of a driver that is less likely to be undetected or erroneously detected while suppressing the amount of data.

  That is, the consciousness decrease determination device according to the present invention provides normal steering amount calculation means for calculating steering data whose steering angular velocity is not less than a first predetermined value and not more than a second predetermined value as a normal steering amount during normal driving of the driver. A steering divergence degree calculating means for calculating a divergence degree between the driver's steering amount and the normal steering amount, a steering divergence degree determining means for determining whether or not the steering divergence degree is a predetermined value or more, and a steering divergence degree Consciousness deterrence determining means for determining that the driver is in a state of reduced consciousness when the vehicle is greater than or equal to a predetermined value.

  According to the present invention, among the steering data during the normal driving of the driver, the steering data whose steering angular velocity is not less than the first predetermined value and not more than the second predetermined value is calculated as the normal steering amount. As a result, steering data having a steering angular velocity less than the first predetermined value or greater than the second predetermined value is not calculated as the normal steering amount. Since only more steering can be extracted, it is possible to perform a consciousness deterioration determination that is less likely to be undetected or erroneously detected.

  In the consciousness deterioration determination device according to the present invention, the normal steering amount calculation means normally steers steering data in which the lateral position of the vehicle with respect to the center of the lane is greater than or equal to a third predetermined value and less than or equal to a fourth predetermined value. It may be calculated as a quantity. In addition to the steering angular velocity described above, by selecting the steering data at the lateral position of the vehicle with respect to the center of the lane, it is possible to perform a consciousness deterrence determination that further suppresses the amount of data and further prevents undetected or erroneous detection. Become.

  In the consciousness deterioration determination device according to the present invention, the normal operation may be a fixed time from the start of operation. Although the driver's consciousness is high for a certain time from the start of driving, if all the steering data for the certain time is calculated as a normal steering amount, the amount of data increases. However, in the present invention, since only the steering data in which the steering angular velocity and / or the lateral position of the vehicle is within a predetermined value range is calculated as the normal steering amount, it is possible to suppress the data amount and perform the consciousness deterioration determination. it can.

  ADVANTAGE OF THE INVENTION According to this invention, the consciousness fall determination apparatus which performs the consciousness fall determination of a driver | operator who is hard to produce undetected and a misdetection can be provided, suppressing data amount.

It is a block diagram which shows the outline | summary of the consciousness fall determination apparatus which concerns on embodiment of this invention. It is explanatory drawing of steering angle dispersion | variation (variation of a steering angle). It is explanatory drawing of steering angle dispersion | variation (variation of a steering angle). It is explanatory drawing about the range of the predetermined value of steering angular velocity. It is explanatory drawing which shows the obstacle avoidance of a vehicle. It is explanatory drawing of the horizontal position in the obstacle avoidance of a vehicle. It is a flowchart which shows operation | movement of the consciousness fall determination apparatus of FIG. It is a flowchart which shows the procedure of the calculation of the normal steering amount in step 12 of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is used for the same element or the same equivalent element, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a block diagram showing a schematic configuration of a consciousness deterioration determining apparatus 1 according to an embodiment of the present invention. The consciousness decrease determination device 1 is a device that is mounted on a vehicle and determines whether or not the consciousness of the driver of the vehicle has decreased.

  This consciousness decrease determination device 1 includes a forward detection sensor 2, a vehicle speed sensor 3, a steering angle sensor 4a, a steering angular velocity sensor 4b, an ECU (Electronic Control Unit) 5, and an alarm unit 6.

  The front detection sensor 2 functions as a front detection unit that detects the front of the vehicle. For example, a camera that images the front of the vehicle is used. The front detection sensor 2 is connected to the ECU 5, and the output signal is input to the ECU 5. A captured image or a captured image of the front detection sensor 2 can be used for detecting a traveling route state (for example, a curvature of the traveling route).

  The vehicle speed sensor 3 functions as vehicle speed detection means for detecting the vehicle speed, and for example, a wheel speed sensor is used. The vehicle speed sensor 3 is connected to the ECU 5 and its output signal is input to the ECU 5.

  The steering angle sensor 4a functions as steering angle detection means for detecting the steering angle of the steering wheel of the vehicle. As the steering angle sensor 4a, for example, a steering angle sensor that detects the rotation angle of the steering shaft is used. The steering angle sensor 4a is connected to the ECU 5, and the output signal is input to the ECU 5. A steering torque sensor may be used instead of the steering angle sensor 4a. In this case, the steering angle of the steering wheel is calculated based on the steering torque value output by the steering torque. Further, as long as the steering angle of the steering wheel can be acquired, any one of them may be used instead of the steering angle sensor 4a.

  The steering angular velocity sensor 4b is a sensor that detects the steering angular velocity input from the steering wheel. The steering angular velocity sensor 4b is connected to the ECU 5, and an output signal thereof is input to the ECU 5.

  The ECU 5 is an electronic control unit that controls the entire apparatus of the consciousness determination device. The ECU 5 mainly includes, for example, a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The circuit includes an output signal circuit and a power supply circuit.

  The ECU 5 includes at least a normal steering amount calculation unit 51, a steering divergence degree calculation unit 55, a steering divergence degree determination unit 56, a consciousness decrease determination unit 57, and an alarm control unit 58.

  The normal steering amount calculation unit 51 calculates the steering amount in the normal driving (when the consciousness is not lowered) of the vehicle driver, and functions as a normal steering amount calculation means. The normal steering amount calculation unit 51 calculates steering data as a normal steering amount during normal driving. The steering data is not particularly limited as long as it is data related to steering. For example, the steering data may be steering angle, steering angle dispersion (variation of steering angle), or steering torque.

  Hereinafter, steering angle dispersion will be described as an example of steering data. The normal steering amount is calculated as the variance of the steering angle of the steering wheel during driving without consciousness reduction for each driver. For example, a plurality or a plurality of steering angles of the steering wheel during driving without consciousness reduction are acquired, and a normal steering amount is calculated as steering angle dispersion based on the steering angle data.

  2 and 3 are explanatory diagrams of steering angle dispersion. As shown in FIG. 2, the dispersion of the steering angle at the time of awakening (during driving without consciousness decrease) is large for subject A and smaller for subject B than A. As described above, individual differences in steering angle dispersion are seen for each driver. For this reason, when the threshold value is made constant, the subject A with a large variation in the steering angle is erroneously detected as being in a consciousness drop state even when awake. On the other hand, as shown in FIG. 3, when a threshold value corresponding to the variance of the steering angle is set for each subject, it becomes easy to prevent undetected and erroneous detection in the consciousness deterioration determination.

  FIG. 4 is an explanatory diagram regarding a range of a predetermined value of the steering angular velocity. As described above, the normal steering amount is calculated as the steering angle variance based on the steering angle data obtained by acquiring a plurality or many steering angles of the steering wheel during normal driving for each driver. However, for example, when 10 minutes from the start of driving is set as the normal driving time, many steering angles of the steering wheel for 10 minutes are acquired, and the normal steering amount is calculated based on the steering angle data, resulting in a large data load. turn into. In addition, when steering angle data having a steering angular velocity equal to or greater than a predetermined value is calculated, even steering data having a very high steering angular velocity may be included.

Therefore, in the consciousness determination apparatus of the present embodiment, two predetermined values, ie, a first predetermined value (lower limit) and a second predetermined value (upper limit) are obtained for the steering angular velocity data acquired simultaneously with the driver's steering angle data. Set and calculate only the steering angle data whose steering angular velocity is not less than the first predetermined value (A ₁ or A ₂ in FIG. 4) and not more than the second predetermined value (B ₁ or B ₂ in FIG. 4). To do. As a result, the amount of calculation of the steering angle data can be reduced while obtaining the steering angle dispersion of the portion necessary for consciousness determination, and the data load is reduced. In FIG. 4, A ₁ and B ₁ indicate steering angular velocities in steering in the right direction, and A ₂ and B ₂ indicate steering angular velocities in steering in the left direction. In other words, in the case of steering in the right direction, steering data with a steering angular velocity of A ₁ or more and B ₁ or less is calculated, and in the case of steering in the left direction, steering data with a steering angular velocity of A ₂ or more and B ₂ or less is calculated. The steering angular velocity means an absolute value of the steering angular velocity.

FIG. 5 is an explanatory view showing obstacle avoidance of the vehicle. As shown in FIG. 5, when the vehicle 70 urgently avoids the obstacle 80, the steering angular velocity becomes extremely large. Also in this case, as described above, when steering angle data having a steering angular velocity equal to or higher than a predetermined value is calculated, such steering angular velocity may be included in the steering data. Therefore, as shown in FIG. 6, a third predetermined value (C ₁ ) and a fourth predetermined value (C ₂ ) are set for the lateral position of the vehicle 70 with respect to the center of the lane, and the vehicle with respect to the center of the lane of the steering data is set. the lateral position is at a third predetermined value or more, and may be calculated fourth steering data is below a predetermined value (data between C ₁ and C ₂₎ as a normal steering amount. As a result, undetected or erroneous detection is less likely to occur, and the amount of data calculated as the normal steering amount is also suppressed.

  The steering angle may be a relative steering angle (relative steering angle) with respect to a travel path on which the vehicle travels. The relative steering angle is a relative steering angle with respect to the travel path. That is, the relative steering angle is small in the case of a steering operation along the traveling road, but the relative steering angle is large in the case of a steering operation not along the traveling road. For example, when the steering wheel is operated on a curve with a large curvature, the absolute value of the steering angle of the steering wheel is large, but when the steering wheel is operated along the curve, the relative steering angle is small. Thus, by calculating the normal steering amount based on the relative steering angle rather than the steering angle (the absolute value thereof), the driver's steering operation characteristics can be accurately determined even when traveling on a curved road. Can be calculated.

  Further, the steering angle information for calculating the normal steering amount may be acquired at the initial stage of the vehicle operation, for example, within a certain time (set time) from the start of the vehicle operation. In the initial stage of driving, there is a high probability that the driver is in an awake state, and it is possible to accurately obtain steering data when the consciousness is not lowered. In addition, in the consciousness determination apparatus according to the present embodiment, only the steering angle dispersion having a steering angular velocity equal to or greater than a predetermined value is calculated as the normal steering amount, so that an increase in the data amount is also suppressed.

  In addition to the steering angle dispersion, the normal steering amount can be a numerical value other than the steering angle variation amount during normal driving, such as a steering amount integrated value, as long as it can represent the driver's normal steering characteristics. May be used to calculate.

The steering divergence calculating unit 55 functions as a steering divergence calculating means for calculating a divergence (steering divergence) between the steering amount of the vehicle driver and the normal steering amount. For example, the steering divergence degree calculation unit 55 calculates the current steering amount of the driver using the steering angle data acquired by the steering angle sensor 4, and the current steering amount is calculated as shown in the following equation (1). The steering divergence D ₁ is calculated by dividing the steering angle (ψ, absolute value), which is the amount, by the steering angle dispersion value (ψu ₁ ), which is the normal steering amount calculated by the normal steering amount calculation unit 51. .
D ₁ = | ψ | / ψu ₁ (1)

In the case of using the relative steering angle, the steering alienation D _2, Pusaiaru the relative steering angle of the present time, if the value of the relative steering angle dispersion is usually steering amount was Pusaiu _2, steering discrepancy D ₂ is , as shown in the following equation (2), it is calculated from dividing the absolute value of the relative steering angle ψr a relative steering angle dispersion value Pusaiu ₂ is a normal steering amount.
D ₂ = | ψr | / ψu ₂ (2)

The relative steering angle ψr is a relative steering angle with respect to the travel path. The relative steering angle ψr is calculated by subtracting the estimated steering angle ψe from the actual steering angle ψ as shown in the following equation (3).
ψr = ψ−ψe (3)

The estimated steering angle ψe is a steering angle necessary for turning a curve on the traveling road, and is calculated by the following equation (4), for example.
ψe = (1 + Kh · v ² ) · l · ρ · R _G (4)
In this equation (4), Kh is the vehicle stability factor, v is the vehicle speed, l is the vehicle wheel base, ρ is the curvature of the road, and _RG is the vehicle steering gear ratio.

  The steering deviation degree determination unit 56 functions as a steering deviation degree determination unit that determines whether or not the steering deviation degree is equal to or greater than a predetermined value. For example, the steering divergence degree determination unit 56 determines whether or not the steering divergence degree calculated by the above-described steering divergence degree calculation unit 55 is greater than or equal to a preset value set in the ECU 5.

  The consciousness decrease determination unit 57 functions as a consciousness decrease determination unit that determines that the driver is in a consciousness decrease state when the steering divergence degree is determined to be greater than or equal to a predetermined value. For example, when the driver is determined to be in a state of reduced consciousness, the consciousness decrease determination unit 57 turns on the consciousness reduction flag to recognize that the driver is in a state of reduced consciousness. When the determination is made, the consciousness reduction flag is turned off to recognize that the driver is not in a consciousness reduction state.

  The alarm control unit 58 controls the output of an alarm control signal to the alarm unit 6 when the driver is in a state of reduced consciousness, and functions as an alarm control unit.

  The above-described normal steering amount calculation unit 51, steering divergence degree calculation unit 55, steering divergence degree determination unit 56, consciousness decrease determination unit 57, and alarm control unit 58 provide the ECU 5 with software such as a program for executing these functions or processes. It is configured by introducing.

  Note that the normal steering amount calculation unit 51, the steering divergence degree calculation unit 55, the steering divergence degree determination unit 56, the consciousness decrease determination unit 57, and the alarm control unit 58 are individually provided as long as their functions or processes can be executed. It may be configured by hardware.

  The alarm unit 6 is an alarm unit that gives an alarm to the driver of the vehicle, and operates according to an alarm control signal output from the ECU 5. As this warning part 6, what gives a warning to a driver through a driver's hearing, vision, and touch is used. For example, as the alarm unit 6, a speaker, a buzzer, a monitor of a navigation system, a display, a lamp, an LED, a handle or a vibration device installed on a seat is used.

  Next, operation | movement of the consciousness fall determination apparatus 1 which concerns on this embodiment is demonstrated. Here, a case where steering angle dispersion is used as an example of steering data will be described below.

  FIG. 7 is a flowchart showing the operation of the consciousness degradation determination apparatus 1. A series of control processes shown in this flowchart are repeatedly executed at a cycle (for example, 100 ms) preset by the ECU 5, for example.

  The control process of this flowchart is started, for example, when the ignition of the vehicle is turned on. First, in step S10 (hereinafter referred to as “S10”, the same applies to other steps), sensor information reading processing is performed. This sensor information reading process is a process of reading sensor information included in output signals of the front detection sensor 2, the vehicle speed sensor 3, and the steering angle sensor 4a.

  Next, the process proceeds to S12, and a normal steering amount calculation process is performed. The normal steering amount calculation process is a process of calculating the steering amount in the normal driving (when the consciousness is not lowered) of the vehicle driver, and is executed by the normal steering amount calculating unit 51, and the steering angle in the normal driving. Variation amount (variance) is calculated as the normal steering amount. More specific calculation processing will be described later.

  Next, the process proceeds to S14, and a steering deviation degree calculation process is performed. The steering divergence degree calculation process is a process of calculating a divergence degree (departure degree) between the steering amount of the vehicle driver and the normal steering amount, and is executed by the steering divergence degree calculating unit 55. For example, the current steering amount of the driver is calculated based on the steering angle data acquired by the steering angle sensor 4a, and the current steering amount is converted to the variance of the relative steering angle that is the normal steering amount calculated in S12 ( The steering deviation degree is calculated by dividing by (relative steering angle dispersion). The steering divergence degree is calculated as the degree of difference between the current steering angle and the normal steering amount with respect to the steering amount at the normal time when the consciousness is not lowered, and is grasped as the distance between the current steering angle and the normal steering amount. . Specifically, the steering divergence degree is calculated using the above-described formula (1) or (2).

  And a process transfers to S16 and it is determined whether a steering deviation degree is more than predetermined value. This determination process is executed by the steering deviation determination unit 56. For example, in the steering divergence degree determination process, it is determined whether or not the steering divergence degree calculated in S14 is greater than or equal to a preset value set in the ECU 5 in advance.

  If it is determined in S16 that the steering divergence degree is less than the predetermined value, the determination process in the consciousness decrease determination unit 57 determines that the driver is not in a consciousness decrease state, and the process proceeds to S18.

  In S <b> 18, recognition processing that does not indicate a decrease in consciousness is performed by the consciousness decrease determination unit 57. For example, a flag for recognizing a driver's consciousness reduction state is turned off.

  On the other hand, when it is determined in S16 that the steering divergence degree is equal to or greater than a predetermined value, a consciousness decrease determination process is performed (S20). For example, a flag for recognizing a driver's reduced awareness state is turned on, and the flag recognizes that the driver is in a reduced awareness state.

  And a process transfers to S22 and an alarm process is performed. The alarm process is a process for outputting an alarm control signal to the alarm unit 6. By this alarm processing, the alarm unit 6 issues an alarm operation to the driver, for example, emits a sound or alarm sound, displays an alarm on the monitor or display, or gives an alarm vibration to the handle or seat. As a result, the driver changes from the consciousness lowered state to the awakened state. When the process of S18 or S22 is finished, a series of control processes are finished.

  FIG. 8 is a flowchart showing an example of the procedure for calculating the normal steering amount in step 12 of FIG. In the present embodiment, the normal steering amount calculation unit 51 is steering angle data in which the steering angular velocity acquired by the steering angular velocity sensor 4b is not less than a first predetermined value and not more than a second predetermined value during normal driving. There is also a function of calculating steering data in which the lateral position of the vehicle is not less than a third predetermined value and not more than a fourth predetermined value as a normal steering amount. Hereinafter, a case where the steering data is steering angle dispersion will be described as an example.

  In S60, the normal steering amount calculation unit 51 determines whether the steering angular velocity is greater than or equal to a first predetermined value and less than or equal to a second predetermined value with respect to the steering angle dispersion during normal driving. When the steering angular velocity is not less than the first predetermined value and not more than the second predetermined value, it is determined whether or not the lateral position of the vehicle with respect to the lane center is not less than the third predetermined value and not more than the fourth predetermined value (S62). . When the lateral position of the vehicle with respect to the center of the lane is not less than the third predetermined value and not more than the fourth predetermined value in S62, the steering angle dispersion is calculated as the normal steering amount (S66).

  On the other hand, when the steering angular velocity is not the first predetermined value or more and not the second predetermined value or less (S60), or when the lateral position of the vehicle with respect to the lane center is not the third predetermined value or more and the fourth predetermined value or less (S62). ) Does not calculate the steering angle dispersion as the normal steering amount (S64). If the steering angular velocities of all the steering angles do not satisfy the above requirement, the steering angle dispersion is not calculated as the normal steering amount. Therefore, if the calculation result that is the past retained data is used as the normal steering amount instead. Good.

  As described above, according to the consciousness decrease determination device according to the present embodiment, the steering data in which the steering angular velocity is not less than the first predetermined value and not more than the second predetermined value during the normal driving of the driver is used as the normal steering amount. A normal steering amount calculating means for calculating, a steering divergence calculating means for calculating a divergence degree between the driver's steering amount and the normal steering amount, and a steering divergence degree for determining whether or not the steering divergence degree is a predetermined value or more. When the degree of steering divergence is equal to or greater than a predetermined value, the detection means is provided with a consciousness reduction determination means that determines that the driver is in a state of reduced consciousness. It is possible to determine a difficult driver consciousness reduction state.

  In addition, embodiment mentioned above demonstrated embodiment of the consciousness fall determination apparatus based on this invention, and the consciousness fall determination apparatus based on this invention is not limited to what was described in this embodiment. The consciousness decrease determination apparatus according to the present invention may be modified from the consciousness decrease determination apparatus according to the embodiment or applied to other things so as not to change the gist described in each claim.

  For example, in the series of control processes shown in FIGS. 7 and 8, if the operational effect of the consciousness deterioration determination device according to the present embodiment can be obtained, a part of the processes may be omitted or additional processes may be performed. .

  Further, the curvature of the travel route is not particularly limited to the detection by the camera image described above. For example, it can be detected based on road route information read from a database stored in a navigation system that can be provided in the consciousness degradation determination device 1 or road shape information acquired from infrastructure information such as road-to-vehicle communication.

  DESCRIPTION OF SYMBOLS 1 ... Consciousness fall determination apparatus, 2 ... Front detection part, 3 ... Vehicle speed sensor, 4a ... Steering angle sensor, 4b ... Steering angular velocity sensor, 5 ... ECU, 6 ... Alarm part, 51 ... Normal steering amount calculating part, 55 ... Steering Deviation degree calculation unit, 56 ... steering deviation degree determination unit, 57 ... decrease in consciousness determination unit, 58 ... alarm control unit.

Claims (3)

In the low consciousness determination device that determines whether the driver of the vehicle is in a low consciousness state,
Normal steering amount calculation means for calculating, as a normal steering amount, steering data whose steering angular velocity is not less than a first predetermined value and not more than a second predetermined value during normal driving of the driver;
Steering deviation degree calculating means for calculating a deviation degree between the steering amount of the driver and the normal steering amount;
Steering deviation degree determining means for determining whether or not the steering deviation degree is a predetermined value or more;
A consciousness reduction determination device comprising: a consciousness decrease determination unit that determines that the driver is in a consciousness decrease state when the steering deviation degree is equal to or greater than a predetermined value.   The normal steering amount calculation means calculates, as the normal steering amount, steering data in which the lateral position of the vehicle with respect to the center of the lane is not less than a third predetermined value and not more than a fourth predetermined value among the steering data. Described consciousness deterioration determination device.   The consciousness deterioration determination device according to claim 1 or 2, wherein the normal operation is a fixed time from the start of operation.

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