JP2012234294A - Consciousness lowering determination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a consciousness lowering determination device capable of accurately determining a driver's consciousness lowering state by determining driver's consciousness lowering after adding a deviation risk of a vehicle in consideration of a vehicle running state.SOLUTION: A consciousness lowering determination device changes a value lower than an already-regulated threshold (a threshold shown with a broken line) by a predetermined value (or a predetermined rate) to the threshold T and determines the threshold T in the case where the number of held values of deviation risk MLC is higher than a setting number a, and in the case where steering is finally conducted in a vehicle M and it is determined that the stored and held deviation risk MLC is on a declining trend, more specifically, in the case of an excessive correction state after non-steering that results from a major correction of handle operation from a state where the vehicle threatens to deviate from a running lane due to non-steering.

Description

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

  Conventionally, as a technique for determining a state of consciousness reduction of a driver of a vehicle, as described in JP-T-2008-542935, an inattentive state of the driver is detected based on the driving operation state of the driver of the vehicle. What to do is known. That is, the technique described in this publication tries to determine that the driver is in an inadvertent state when a steering operation is performed at a steering angle and a steering speed of a predetermined level or more from a state where there is no steering operation. is there.

Special table 2008-542935 gazette

  However, in such a detection technique, it is assumed whether or not the vehicle jumps out of the roadway in a predetermined driving operation assuming that the driver is in a state of reduced consciousness and is in a non-steering state. When the determination criterion is used, there is a problem in that it is impossible to accurately determine an unfavorable state close to a consciousness state in which the steering operation is correctly performed by returning to the conscious state before the vehicle jumps out of the roadway. This is because if the vehicle returns to the conscious state before the vehicle jumps out of the roadway and the steering wheel operation is correctly performed, the above-described determination criteria are not satisfied.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a low consciousness determination device that can accurately determine a low consciousness state of a driver by performing a low consciousness determination of the driver in consideration of the running state of the vehicle and taking into account the risk of departure from the vehicle. Is to provide.

  That is, the consciousness decrease determination device according to the present invention is a consciousness decrease determination device that determines whether or not a vehicle driver is in a consciousness decrease state, and the driver's steering amount is set with respect to a preset normal steering amount. A steering state determination unit that determines whether or not the vehicle is more than a predetermined value, and a vehicle in which the steering state determination unit determines that the driver's steering amount is more than a predetermined value with respect to a preset normal steering amount. A risk storage means for storing the departure risk for the traveling lane of the vehicle, and when the departure risk stored by the risk storage means tends to decrease, based on the departure risk stored by the risk storage means , A threshold value determining means for determining a threshold value for determining whether or not the driver is in a state of reduced consciousness, and the threshold value for determining the deviation risk stored by the risk level storage means. If it is more, the driver is configured with a diminished awareness determination means determines that drowsiness.

  According to the present invention, when it is determined that the driver's steering amount is more than the preset value with respect to the normal steering amount set in advance, the degree of risk of departure from the traveling lane of the vehicle is stored, and the stored departure is stored. When the risk tends to decrease, a threshold for determining whether or not the driver is in a state of reduced consciousness is determined based on the stored departure risk, and the stored departure risk is When it is equal to or greater than the determined threshold, it is determined that the driver is in a state of reduced consciousness. As a result, the driver's steering amount is far from the preset normal steering amount by more than the set value, and the stored deviation risk tends to decrease, that is, it was not normal steering. The threshold value can be determined based on a state in which driving that reduces the degree of danger is performed by the driver who has noticed and the vehicle has left the deviation from the driving lane. For this reason, it is possible to accurately determine and detect a state that is likely to deviate from the driving lane unless the driver notices it, that is, a state of low consciousness or a state that is likely to occur.

  In the consciousness deterioration determining apparatus according to the present invention, the threshold value determining means may determine the threshold value lower when the stored number of deviation risks stored by the risk storage means is equal to or greater than the set number.

  According to the present invention, the threshold is determined to be lower when the stored number of stored deviation risk degrees is equal to or greater than the set number. As a result, it is possible to more accurately determine a state that is likely to deviate from the traveling lane, that is, a state of reduced consciousness, based on the information of the set number or more, and to reduce the possibility of deviating from the traveling lane.

  According to the present invention, it is possible to accurately determine the driver's consciousness reduction state by performing the driver's consciousness reduction determination in consideration of the traveling state of the vehicle and taking the deviation risk of the vehicle into consideration.

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 the deviation risk calculated in the consciousness fall determination apparatus of FIG. It is explanatory drawing of the threshold value determination method. It is explanatory drawing of the threshold value determination method. It is a flowchart which shows operation | movement of the consciousness fall determination apparatus 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.

  The consciousness decrease determination device 1 includes a front detection sensor 2, a vehicle speed sensor 3, a steering angle sensor 4, 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 the presence or absence of an obstacle and detecting a white line on a traveling road. In some cases, obstacle detection may be performed using another sensor such as a millimeter wave radar or a laser radar as the forward detection sensor 2.

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

  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 a normal steering amount calculation unit 51, a steering divergence degree calculation unit 52, a steering divergence degree determination unit 53, a divergence number calculation unit 54, a divergence state determination unit 55, a threshold value determination unit 56, a non-steering state determination unit 57, a deviation risk. A degree calculating unit 58, a departure risk determining unit 59, a consciousness deterioration determining unit 60, and an alarm control unit 61.

  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, for example, the amount of steering angle variation during normal driving as the normal steering amount.

  More specifically, the normal steering amount is calculated as the variance of the relative steering angle of the steering angle of the steering wheel during driving without consciousness reduction. For example, a plurality of or many relative steering angles of the steering angle of the steering wheel during driving without consciousness reduction are acquired, and the normal steering amount is calculated as the variance of the relative steering angle based on the relative steering angle data.

  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 absolute value of the steering angle, the driver's steering operation characteristics can be accurately calculated even when traveling on a curved road. can do.

  Further, the steering angle information for calculating the normal steering amount is acquired at the initial stage of vehicle operation, for example, within a set time from the start of vehicle operation. In the initial stage of driving disclosure, it is highly probable that the driver is in an awake state, and it is possible to accurately acquire steering angle information when the consciousness is not lowered.

  Note that the normal steering amount may be calculated by a numerical value other than the variation amount of the steering angle of the steering wheel during normal driving, such as a steering speed and an integrated steering amount value, as long as the normal steering steering characteristic of the driver can be expressed. Good.

  The steering divergence degree calculation unit 52 functions as a steering divergence degree calculating means for calculating a divergence degree (degree of difference) between the steering amount of the vehicle driver and the normal steering amount. For example, the steering deviation degree calculation unit 52 calculates the current steering amount of the driver using the steering angle data acquired by the steering angle sensor 4, and is calculated by the current steering amount and the normal steering amount calculation unit 51. The steering deviation degree is calculated based on the difference or ratio of the normal steering amount.

  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, when the steering divergence degree is D, the current relative steering angle is ψr, and the normal steering amount ψu, the steering divergence degree D is the absolute value of the relative steering angle ψr as shown in the following equation (1). The value is calculated by dividing the value by the normal steering amount ψu.

D = | ψr | / ψu (1)
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 (2).

ψr = ψ−ψe (2)
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 (3), for example.

ψe = (1 + Kh · v ² ) · l · ρ · R _G (3)
In this equation (3), 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 divergence determination unit 53 functions as a steering state determination unit that determines whether or not the driver's steering amount is more than a preset value away from a preset normal steering amount. For example, the steering divergence degree determination unit 53 determines whether or not the steering divergence degree calculated by the above-described steering divergence degree calculation unit 52 is more than a preset value set in the ECU 5.

  The steering divergence degree determination unit 53, a non-steering state determination unit 57, and a departure risk degree determination unit 59, which will be described later, function as a consciousness reduction determination unit that determines whether or not the driver's consciousness is reduced.

  The departure risk degree calculation unit 58 functions as a departure risk degree calculation means for calculating a departure risk degree with respect to the travel lane of the vehicle. The departure risk is calculated based on at least the vehicle speed, the traveling direction with respect to the traveling lane, and the lateral position with respect to the traveling lane.

  Thus, by calculating the deviation risk with respect to the travel lane of the vehicle based on the vehicle speed, the traveling direction with respect to the travel lane, and the lateral position with respect to the travel lane, the vehicle's physical travel state or behavior state is calculated. Objective deviation risk can be calculated. Compared to the case of calculating the deviation risk of the vehicle only by the lateral position of the vehicle, the vehicle speed and the traveling direction of the vehicle are taken into consideration, so whether the vehicle is trying to avoid an obstacle on the road It is possible to accurately identify whether the person is about to deviate due to a decrease in the consciousness of the person.

  That is, when calculating the vehicle departure risk only from the lateral position of the vehicle, the departure risk is determined to be high when the lateral position of the vehicle is at the end position of the lane. However, in the consciousness deterioration determination device according to the present embodiment, by adding the vehicle speed and the traveling direction of the vehicle to the calculation of the departure risk, the vehicle speed is slow even if the lateral position of the vehicle is at the end position of the lane. If the traveling direction is parallel to the travel path, an appropriate determination can be made if the departure risk is not high.

  The departure risk is calculated as, for example, the minimum yaw rate necessary for avoiding the departure of the vehicle. The departure risk MLC can be calculated by the following equation (4).

MLC = v · (1-cos θ) / (w / 2−y) (4)
As shown in FIG. 2, in equation (4), v is the vehicle speed of the vehicle M, θ is the yaw angle of the vehicle M with respect to the white line (lane marker), w is the lane width, and y is the lateral position of the vehicle M with respect to the lane center Amount). As the vehicle speed v, vehicle speed data based on the output signal of the vehicle speed sensor 3 may be used. As the yaw angle θ, a calculated value of the yaw angle of the vehicle M with respect to the white line may be used based on the output image of the front detection sensor 2. As the lane width w, a lane width value calculated based on an output image of the front detection sensor 2 may be used, or a lane width value acquired based on map information or road information of a navigation system (not shown) may be used. Good. For the lateral position y, an offset amount of the vehicle M calculated based on the output image of the front detection sensor 2 may be used.

  The departure risk may be a value other than the minimum yaw rate necessary for avoiding the departure of the vehicle as long as the risk of departure from the lane of the vehicle becomes larger or smaller. .

  The deviation number calculation unit 54 functions as a risk storage unit that stores the above-described deviation risk degree MLC when the steering deviation degree determination unit 53 determines that the steering deviation degree is more than a set value. . For example, when it is determined that the steering divergence degree is more than a set value, the divergence number calculation unit 54 determines the maximum value among the plurality of deviation risk degrees MLC from the current time to a predetermined time (for example, several seconds to several minutes) before. In addition, the calculation time is stored and held, and the stored number of deviation risk MLC values is incremented by one.

  The divergence state determination unit 55 determines whether or not the retained number of deviation risk MLC values stored and retained is larger than a set number a (a is a preset number represented by an integer) and stored. It functions as a threshold value determination unit that determines whether or not the stored deviation risk MLC tends to decrease when the retained deviation risk MLC value is greater than the set number a. . For example, if the divergence state determination unit 55 determines that the stored number of deviation risk MLC values stored is larger than the set number a, the stored deviation risk MLC is stored as time (calculation time) elapses. It is determined whether or not there is a tendency to decrease.

  The threshold value determination unit 56, when it is determined by the divergence state determination unit 55 that the number of retained deviation risk MLC values is greater than the set number a and the stored retained departure risk MLC tends to decrease. It functions as a threshold value determining means for determining a threshold value for determining whether or not the driver is in a state of reduced consciousness based on the stored deviation risk MLC. For example, when it is determined that the number of retained departure risk MLC values is larger than the set number a and the stored retained departure risk MLC tends to decrease, the threshold determination unit 56 stores and retains these. A value lower than the maximum value of the deviation risk MLC by a predetermined value (or a predetermined ratio) is determined as this threshold value.

  Details of the threshold determination method by the threshold determination unit 56 will be described with reference to FIGS. 3 and 4. FIG. 3 is an explanatory diagram for explaining a threshold determination method by the threshold determination unit 56 when it is not determined that the stored deviation risk MLC tends to decrease. FIG. 4 is a diagram illustrating FIG. It is explanatory drawing for demonstrating the threshold value determination method by the threshold value determination part 56 when it changes to the state from which it was determined that the deviation risk MLC memorize | stored and held had the tendency to reduce. In both FIG. 3 and FIG. 4, the vertical axis indicates the magnitude of the deviation risk MLC, and the horizontal axis indicates the passage of time.

  As shown in FIG. 3 (a), the driver is in a state of reduced consciousness and is not steered for a while in the traveling vehicle M, and the vehicle M is in a state of jumping out of the roadway as it is. As shown in b), if it is not determined that the stored deviation risk MLC tends to decrease, that is, no steering is performed, the steering is not performed and the risk of deviating from the traveling lane increases. In the case of the departure state, the threshold value determination unit 56 sets a value of a size set in advance in the ECU 5 as the threshold value T.

  Here, the retained number of deviation risk MLC values is larger than the set number a, and the vehicle returns to the conscious state before the vehicle M jumps out of the roadway as shown in FIG. When steering is performed at M and it is determined that the stored deviation risk MLC tends to decrease, as shown in FIG. 4B, that is, steering is not performed and the vehicle deviates from the driving lane. In the case of the excessive correction state after no steering where the steering wheel operation has been largely corrected from the state where there is a possibility of the occurrence of the error, the threshold value determination unit 56 indicates the threshold value indicated by the solid line in FIG. 3 (the threshold value indicated by the broken line in FIG. 4). A value lower than the threshold value T by a predetermined value (or a predetermined ratio) is determined and set. This threshold value T is a value that is lower by a predetermined value (or a predetermined ratio) than the maximum value of the deviation risk MLC stored and held.

  The non-steering state determination unit 57 determines whether or not the vehicle driver is in a non-steering state in the steering wheel operation, and functions as a non-steering state determination unit. For example, when the steering angle of the vehicle steering wheel has not changed for a set time or more, it is determined that the vehicle is not steered. When the steering angle of the steering wheel has changed within the set time, it is determined that the vehicle is not in a non-steering state. . At this time, whether or not the steering angle has changed is determined by, for example, determining that there is no change in the steering angle when the steering angle has not changed more than the set angle, and when the steering angle has changed more than the set angle. It is determined that there is a change. As the set time and the set angle, set values set in advance in the ECU 5 are used. The set time and the set angle serve as a determination threshold value for determining whether or not the vehicle is in a non-steering state.

  The departure risk determination unit 59 functions as a departure risk determination unit that determines whether the departure risk of the vehicle is equal to or greater than a set value. As the set value serving as the determination threshold for the departure risk level, a value set in advance in the ECU 5 is used.

  Decrease in consciousness determination unit 60 determines that the driver is in a state of reduced consciousness when deviation risk MLC stored by divergence number calculation unit 54 is equal to or greater than the threshold value determined by threshold value determination unit 56. It functions as a determination means. In addition, when it is determined by the consciousness decrease determination unit 60 that the stored departure risk MLC is not equal to or greater than the determined threshold value, it is determined that the driver is not in a consciousness decrease state.

  For example, when the driver is determined to be in a state of reduced consciousness, the consciousness reduction determination unit 60 turns on the consciousness reduction flag to recognize that the driver is in a state of reduced consciousness, and the driver is not 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 61 functions as an alarm control unit that controls the operation of the alarm unit 6, and outputs an alarm control signal to the alarm unit 6 when it is determined that the vehicle driver is in a state of reduced consciousness. Output.

  The above-described normal steering amount calculation unit 51, steering divergence calculation unit 52, steering divergence degree determination unit 53, divergence number calculation unit 54, divergence state determination unit 55, threshold value determination unit 56, non-steering state determination unit 57, deviation risk The calculation unit 58, the departure risk determination unit 59, the consciousness decrease determination unit 60, and the alarm control unit 61 are configured by introducing software such as a program for executing these functions or processes into the ECU 5.

  In addition, the normal steering amount calculation unit 51, the steering divergence degree calculation unit 52, the steering divergence degree determination unit 53, the divergence number calculation unit 54, the divergence state determination unit 55, the threshold value determination unit 56, the non-steering state determination unit 57, the deviation risk level The calculation unit 58, the departure risk determination unit 59, the consciousness decrease determination unit 60, and the alarm control unit 61 may be configured by individual hardware as long as these functions or processes can be executed.

  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.

  FIG. 3 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 by, for example, turning on the ignition of the vehicle. First, in step S01 (hereinafter referred to as “S01”, the same applies to other steps), sensor information reading process is performed. The 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 4.

  Next, the process proceeds to S02, 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 calculation unit 51. For example, the amount of steering angle variation during normal driving is calculated as the normal steering amount.

  More specifically, the normal steering amount is calculated as the variance of the relative steering angle of the steering angle of the steering wheel during driving without consciousness reduction. For example, a plurality or a plurality of relative steering angles of the steering angle of the steering wheel during normal driving without consciousness reduction are acquired, and the normal steering amount is calculated as the variance of the relative steering angle based on the relative steering angle data. As described above, the relative steering angle is a relative steering angle with respect to the travel path. The normal steering amount calculation process in S02 may be executed as a process different from the series of control processes shown in FIG.

  Next, a steering deviation degree calculation process is performed (S03). The steering divergence degree calculation process is a process for calculating a divergence degree (degree of difference) between the steering amount of the vehicle driver and the normal steering amount, and is executed by the steering divergence degree calculation unit 54. For example, the current steering amount of the driver is calculated based on the steering angle data acquired by the steering angle sensor 4, and the steering divergence is based on the difference or ratio between the current steering amount and the normal steering amount calculated in S02. The degree is calculated. 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 equation (1).

  Then, the process proceeds to S04, and it is determined whether or not the driver's steering amount is more than a set value by a predetermined normal steering amount. This determination process is executed by the steering deviation determination unit 53. For example, in the steering divergence degree determination process, it is determined whether or not the steering divergence degree calculated in S03 is more than a set value set in advance in the ECU 5. This S04 and steering deviation determination processing of S14 described later, non-steering state determination processing of S10 described later, and departure risk determination processing of S12 are consciousness deterioration determination processing for determining whether or not the driver's consciousness is reduced. It functions as.

  If it is determined in S04 that the driver's steering amount is not far from the preset normal steering amount by more than the set value, it is determined that the driver is not in a state of reduced consciousness, and the process proceeds to S05.

  On the other hand, when it is determined in S04 that the driver's steering amount is more than the preset value by a predetermined normal steering amount, the process proceeds to S06. In S06, the divergence number calculation unit 54 stores and holds the maximum value and the calculation time thereof among a plurality of deviation risk MLCs from the present time to a predetermined time (for example, several seconds to several minutes) before. Then, the process proceeds to S07, and the divergence number calculation unit 54 counts up the stored number of deviation risk MLC values by one.

  Then, the process proceeds to S08, and the divergence state determination unit 55 determines whether or not the retained number of deviation risk MLC values stored and retained is greater than the set number a. If it is not determined that the retained number of deviation risk MLC values stored and retained is greater than the set number a, the process returns to S06 and the process proceeds. On the other hand, if it is determined that the stored number of stored deviation risk MLC values is greater than the set number a and it is determined that the stored departure risk MLC tends to decrease, the process proceeds to S09. Will migrate.

  In S09, the threshold value determination unit 56 determines a value that is a predetermined value (or a predetermined ratio) lower than the maximum value of the stored deviation risk MLC as this threshold value. And a process transfers to S10 and it is determined whether a vehicle is a non-steering state. This determination process is a process of determining whether or not the vehicle driver is in a non-steering state in the steering operation, and is executed by the non-steering state determining unit 57. For example, when the steering angle of the vehicle steering wheel has not changed for a set time or more, it is determined that the vehicle is not steered. When the steering angle of the steering wheel has changed within the set time, it is determined that the vehicle is not in a non-steering state. . At this time, whether or not the steering angle has changed is determined as no change in the steering angle when the steering angle has not changed more than the set angle, and there has been a change in the steering angle when the steering angle has changed more than the set angle. It is determined. As the set time and the set angle, set values set in advance in the ECU 5 are used.

  If it is determined in S10 that the vehicle is not in a non-steering state, it is determined that the driver is not in a state of reduced consciousness, and the process proceeds to S05. On the other hand, when it is determined in S10 that the vehicle is in the non-steering state, departure risk degree calculation processing is performed (S11).

  The departure risk degree calculation process is a process of calculating a departure risk degree MLC for the travel lane of the vehicle, and is executed by the departure risk degree calculation unit 58. The departure risk MLC is calculated based on at least the vehicle speed, the traveling direction with respect to the traveling lane, and the lateral position with respect to the traveling lane. The departure risk degree MLC is calculated as, for example, the minimum yaw rate necessary for avoiding the departure of the vehicle. The departure risk MLC is calculated by, for example, the above-described equation (4).

  Then, the process proceeds to S12, and it is determined whether or not the deviation risk MLC of the vehicle is equal to or greater than a threshold value. This determination process is executed by the departure risk determination unit 59. For example, it is determined whether or not the vehicle departure risk MLC calculated in S11 is equal to or greater than a preset threshold value in S09. In this case, the greater the deviation risk MLC, the higher the risk that the vehicle will deviate.

  If it is determined in S12 that the deviation risk MLC of the vehicle is not greater than or equal to the set value, it is determined that the driver is not in a state of reduced consciousness, and the process proceeds to S05. On the other hand, when it is determined in S12 that the deviation risk MLC of the vehicle is greater than or equal to the set value, a steering deviation degree calculation process is performed (S13).

  The steering divergence degree calculation process is a process for calculating a divergence degree (degree of difference) between the steering amount of the vehicle driver and the normal steering amount, and is executed by the steering divergence degree calculation unit 52. For example, the current steering amount of the driver is calculated based on the steering angle data acquired by the steering angle sensor 4, and the steering divergence is based on the difference or ratio between the current steering amount and the normal steering amount calculated in S02. The degree is calculated. 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 equation (1).

  Then, the process proceeds to S14, in which it is determined whether or not the driver's steering amount is more than a set value by a predetermined normal steering amount. This determination process is executed by the steering deviation determination unit 53. For example, in the steering divergence degree determination process, it is determined whether or not the steering divergence degree calculated in S13 is more than a set value set in advance in the ECU 5. The steering deviation determination process of S04 and S14 described above, the non-steering state determination process of S10, and the deviation risk determination process of S12 described above are consciousness decrease determination processes for determining whether or not the driver's consciousness is reduced. It functions as.

  If it is determined in S14 that the steering amount of the driver is not set apart from the preset normal steering amount by more than the set value, it is determined that the driver is not in a state of reduced consciousness, and the process proceeds to S05.

  In S05, a recognition process is performed to indicate that the consciousness is not lowered. For example, a flag for recognizing a driver's consciousness reduction state is turned off.

  On the other hand, when it is determined in S14 that the driver's steering amount is more than the preset value by a predetermined normal steering amount, a consciousness reduction determination process is performed (S15). In the consciousness reduction determination process, since it is determined that the vehicle is in a non-steering state, the deviation risk of the vehicle is greater than or equal to a set value, and the steering deviation is greater than or equal to a set value, This is a process of determining and recognizing that the state is a lowered state. 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 S16 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 processes of S05 and S16 are finished, a series of control processes are finished.

  As described above, according to the consciousness decrease determination device according to the present embodiment, first, when it is determined that the driver's steering amount is more than the preset value with respect to the preset normal steering amount, the vehicle The departure risk MLC for M lanes is stored. Here, when the stored departure risk MLC tends to decrease, a threshold T for determining whether or not the driver is in a state of reduced consciousness is determined based on the stored departure risk MLC. To do. When the stored deviation risk MLC is equal to or greater than the determined threshold T, it is determined that the driver is in a state of reduced consciousness.

  As a result, the driver's steering amount is far from the preset normal steering amount by a set value or more, and the stored deviation risk MLC tends to decrease as shown in FIG. 4 (b). The threshold value can be determined based on a certain state, that is, a state where the driver who notices that the vehicle is not normally steered performs a driving operation that reduces the degree of danger and escapes from the deviation of the traveling lane. For this reason, it is possible to accurately determine and detect a state that is likely to deviate from the driving lane unless the driver notices it, that is, a state of low consciousness or a state that is likely to occur.

  For example, as a comparative example for the consciousness deterioration determination device according to the present embodiment, there is a function of determining a threshold value that is a predetermined value (or a predetermined ratio) lower than the maximum value of the stored deviation risk MLC. If not, the threshold value indicated by the broken line in FIG. 4B remains, so that the steering operation is largely corrected from the state where the steering operation is not performed and there is a possibility of deviating from the traveling lane. The state (the state of FIG. 4A) cannot be determined and detected.

  On the other hand, in the consciousness decrease determination apparatus according to the present embodiment, a function (learning function) that determines a value that is lower than the maximum value of the stored deviation risk MLC by a predetermined value (or a predetermined ratio) as a threshold value (learning function). As shown in FIG. 4B, the steering wheel is not steered and there is a risk of deviating from the driving lane. Can detect and detect events.

  Moreover, in the consciousness deterioration determination apparatus according to the present embodiment, when the stored number of stored deviation risk degrees MLC is equal to or greater than the set number, the threshold T is determined to be lower as described above. As a result, it is possible to more accurately determine the state that is likely to deviate from the driving lane, i.e., the state of low consciousness or the state that is likely to occur, and to deviate from the driving lane based on the information of the set number or more. Can be lower.

  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, the determination processing in S10, S12, and S14 in FIG. 5 may be executed by changing the order. Further, in the series of control processes of FIG. 5, if the operation and effect of the consciousness decrease determination device according to the present embodiment can be obtained, a part of the processes may be omitted or additional processes may be performed.

  DESCRIPTION OF SYMBOLS 1 ... Consciousness fall determination apparatus, 2 ... Front detection sensor, 3 ... Vehicle speed sensor, 4 ... Steering angle sensor, 5 ... ECU, 6 ... Alarm part, 51 ... Normal steering amount calculating part, 52 ... Steering deviation degree calculating part, 53 ... Steering deviation degree determination part, 54 ... Deviation frequency calculation part, 55 ... Deviation state determination part, 56 ... Threshold determination part, 57 ... No steering state determination part, 58 ... Deviation risk degree calculation part, 59 ... Deviation risk degree determination part , 60 ... Decrease in consciousness determination unit, 61 ... Alarm control unit, M ... Vehicle.

Claims (2)

In the low consciousness determination device that determines whether the driver of the vehicle is in a low consciousness state,
Steering state determination means for determining whether or not the driver's steering amount is more than a predetermined value with respect to a preset normal steering amount;
A risk storage for storing a risk of departure of the vehicle from the driving lane when it is determined by the steering state determination means that the steering amount of the driver is greater than a preset normal steering amount by a set value or more. Means,
Whether or not the driver is in a state of reduced consciousness based on the departure risk stored by the risk storage means when the departure risk stored by the risk storage means tends to decrease. Threshold value determining means for determining a threshold value for determining whether or not
Consciousness deterioration determining means for determining that the driver is in a state of reduced consciousness when the deviation risk stored by the risk storage means is greater than or equal to the threshold determined by the threshold determining means;
A device for determining consciousness deterioration, comprising: The threshold value determining means determines the threshold value lower when the stored number of deviation risks stored by the risk storage means is a set number or more.
The consciousness fall determination apparatus according to claim 1.

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