JP2015162127A - Lane deviation prevention support device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lane deviation prevention support device capable of determining lane deviation at timing closer to a driver's sensibility.SOLUTION: A control unit 10 detects a center of a lane where an own vehicle 1 travels, and when a lateral deviate amount on the center of the own vehicle 1 to the detected center of the lane exceeds a predetermined threshold, determines lane deviation. When the control unit 10 determines lane deviation, the control unit 10 actuates an alarm 22, and drives a steering device 21. The control unit 10 individually sets a threshold to the deviate amount to a right side of the own vehicle progress direction, and a threshold to the deviate amount to a left side of the own vehicle progress direction, as the threshold, and sets the threshold on a side where the driver is positioned on the own vehicle 1, smaller than the threshold on an opposite side.

Description

  The present invention relates to a lane departure prevention support device, and belongs to the technical field of a drive support device that supports a driver of a vehicle.

  2. Description of the Related Art Conventionally, there is known a lane departure prevention support device that assists a driver in driving a vehicle so as to prevent the vehicle from deviating from the lane by mistake. For example, Patent Literature 1 discloses a driving support device that outputs an alarm or assists steering in the direction of the lane center when the lateral deviation amount of the host vehicle from the lane center exceeds a predetermined threshold. In particular, Patent Document 1 discloses a case where the driver brings his or her vehicle to the right (in the case of a right-hand drive vehicle) or left (in the case of a left-hand drive vehicle) in the lane in order to confirm the road condition ahead of the preceding vehicle. It is disclosed that the threshold value on the side where the steering handle is mounted in the own vehicle is increased in order to suppress an inappropriate control such that an alarm is issued or the own vehicle is returned to the center of the lane. Yes.

Japanese Patent No. 4760563 (paragraphs 0019 and 0030)

  By the way, in this type of driving support device, the threshold value is set based on the center of the vehicle. That is, a lane departure is determined when the lateral deviation amount (lateral deviation amount) of the vehicle center with respect to the lane center exceeds a predetermined threshold. However, in the case of a right-hand drive vehicle, for example, the driver is positioned on the right side of the vehicle center in the host vehicle. That is, the driver is biased to the right in the traveling direction from the center of the lane since the host vehicle is traveling in the center of the lane. Therefore, when the vehicle is deviated to the right in the traveling direction and a lane departure is determined, the driver feels that the determination timing is late because the driver is relatively large in the lane and is moving to the right. Conversely, when the vehicle is biased to the left in the traveling direction and a lane departure is determined, the driver feels that the timing of the determination is early because the driver is not so far left in the lane. That is, in any case, the lane departure is determined at a timing that does not coincide with the driver's feeling. Such a problem also occurs in the case of a left-hand drive vehicle.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a lane departure prevention support device that can determine lane departure at a timing closer to the driver's feeling.

  In order to solve the above-mentioned problems, the present invention provides a lane center detecting means for detecting the center of a lane in which the host vehicle travels, and a lateral deviation amount of the center position of the host vehicle with respect to the center of the detected lane is predetermined. A lane departure prevention assisting device having a determination means for determining lane departure when a threshold value of the vehicle is exceeded, wherein the threshold value is a threshold value for a lateral deviation amount on the right side in the traveling direction of the host vehicle and a threshold value for a lateral deviation amount on the left side. And setting means for setting the threshold value on the side where the driver is located in the own vehicle to a value smaller than the threshold value on the opposite side.

  According to the present invention, for example, in the case of a right-hand drive vehicle, the threshold for the lateral deviation amount to the right in the traveling direction of the host vehicle is set to a relatively small value, and the threshold for the lateral deflection amount to the left is set to a relatively large value. Is set. Therefore, when the vehicle deviates from the center of the lane to the right side, the lane departure is determined at a relatively early timing. Conversely, when the vehicle deviates from the center of the lane to the left side, the lane departure is determined at a relatively late timing. The As a result, the lane departure is determined at a timing closer to the sense of the driver sitting closer to the right side of the vehicle center from when the host vehicle is traveling in the center of the lane. Such an effect is similarly achieved in the case of a left-hand drive vehicle.

  In short, the present invention sets the lane departure determination threshold value that is conventionally set based on the vehicle center reference based on the driver reference so that the lateral separation distance between the lane center and the vehicle center becomes the right side in the traveling direction. Lane departure was determined when the left side increased to the same extent on the left side, but the lane departure occurred when the lateral separation distance between the center of the lane and the driver increased to the same extent on the right side and left side in the traveling direction. In this configuration, the timing at which lane departure is determined is brought close to the driver's feeling.

  In the present invention, preferably, the setting means corresponds to a distance in the vehicle width direction between the center of the vehicle and the center of the driver's seat, rather than a predetermined basic threshold value set to the same value on the right and left sides in the traveling direction of the host vehicle. The threshold value on the side where the driver is located is reduced by the value, and the threshold value on the opposite side is increased.

  According to this configuration, since the threshold value on the side where the driver is located and the threshold value on the opposite side are set based on the distance in the vehicle width direction between the vehicle center and the driver seat center, the threshold value can be set reasonably and easily. The lane departure is determined at a timing closer to the driver's feeling.

  In the present invention, preferably, the determination means predicts the center position of the host vehicle after a predetermined time has elapsed from the present time, and the lateral deviation amount of the predicted center position of the host vehicle with respect to the center of the lane exceeds the threshold value. When it exceeds, lane departure is judged.

  According to this configuration, since a lane departure after a predetermined time is determined, the lane departure is reliably avoided with a time margin.

  In the present invention, preferably, an alarm device for alerting the driver, a steering device for steering the host vehicle, and when the lane departure is determined by the determination means, the alarm device and the steering device Control means for operating at least one of the above.

  According to this configuration, when the lane departure is determined, the driver's attention is alerted or the host vehicle is steered in a direction to avoid the lane departure, so appropriate measures are taken to avoid the lane departure. It is done.

  The present invention provides a lane departure prevention support device in which lane departure is determined at a timing closer to the driver's sense, and thus contributes to the development and improvement of the technology of the drive support device that supports the driver's vehicle driving.

1 is a system configuration diagram of a lane departure prevention support apparatus according to an embodiment of the present invention. It is a flowchart of the control action which the control unit of the said lane departure prevention assistance apparatus performs. It is explanatory drawing of an effect | action of the said lane departure prevention assistance apparatus. It is a graph which shows the distance of a vehicle center and a white line when a driver | operator feels possibility of lane departure in a right-hand drive vehicle, (a) is a test result in case a driver | operator is the test subject A, (b) is a driver | operator. Is the test result for subject B. Is an explanatory view when the driver in a right hand drive vehicle feels the possibility of lane departure, (a) shows the shows the distance D _L, D _R of the vehicle center and the white line, (b) is a driver and the white line Distances D _L ′ and D _R ′.

(1) Overall Configuration As shown in FIG. 1, a vehicle 1 according to this embodiment is a right-hand drive vehicle in which a steering handle and a driver's seat (both not shown) are arranged on the right side of the vehicle center (not shown). 5), a lane departure prevention support device including a front sensing camera 11, a vehicle speed sensor 12, a yaw rate sensor 13, a steering device 21, and an alarm device 22 is mounted around the control unit 10.

  The control unit 10 is a microprocessor including a CPU, a ROM, a RAM, and the like, and corresponds to a lane center detection unit, a vehicle center position detection unit, a determination unit, a setting unit, and a control unit of the present invention.

  The front sensing camera 11 is an optical camera such as a CMOS (Complementary Metal Oxide Semiconductor) camera, and images the front of the vehicle 1.

  The control unit 10 processes the image data picked up by the front sensing camera 11, and the lateral position yo [m] and yaw angle ψo [rad] of the host vehicle 1 and the curvature R [1 / m] of the lane in which the host vehicle 1 travels. ], The clothoid parameter A [1 / m / m] and the lane width W [m].

  The control unit 10 acquires information regarding the vehicle speed V [m / s] detected by the vehicle speed sensor 12 and information regarding the yaw rate γo [rad / s] detected by the yaw rate sensor 13.

  The steering device 21 includes, for example, a motor and a reduction gear mechanism (both not shown) for steering the host vehicle 1. The alarm device 22 includes, for example, a buzzer (not shown) for alerting the driver. Then, the control unit 10 determines the lane departure of the host vehicle 1 based on the various information, and when the lane departure is determined, the control device 10 operates the steering device 21 and the warning device 22 to avoid the lane departure. Steer the vehicle 1 in the direction or call the driver's attention.

(2) Control content Next, the control operation performed by the control unit 10 will be described with reference to FIG.

  First, the control unit 10 reads various physical quantities in step S1. These physical quantities include the lateral position yo, the yaw angle ψo, the curvature R, the clothoid parameter A and the lane width W generated from the image data of the front sensing camera 11, the vehicle speed V detected by the vehicle speed sensor 12, and the yaw rate. The yaw rate γo detected by the sensor 13 is included.

  Further, the control unit 10 sets a basic alarm area threshold Lo [m]. As shown in FIG. 3, the basic alarm area threshold Lo is a lateral distance from the white line defining the left and right ends of the lane toward the center of the lane. Areas on the right and left sides of the lane from the basic alarm area threshold Lo are basic alarm areas. In the example of FIG. 3, reference symbol L <b> 1 is attached to the right basic alarm area on the right side in the traveling direction of the host vehicle, and reference symbol L <b> 2 is attached to the left basic alarm area. In the present embodiment, the basic alarm area threshold Lo is customized for each vehicle or driver, at the time of vehicle shipment, or by learning control during traveling. The basic alarm area threshold Lo is set to the same value on the right side and the left side in the traveling direction of the host vehicle.

  The control unit 10 stores an alarm area threshold correction amount Lc [m]. In the present embodiment, the alarm area threshold correction amount Lc is a value corresponding to the distance in the vehicle width direction (for example, 0.3 m) between the vehicle center and the driver seat center, as will be described later.

Then, the control unit 10, in step S2, according to the following formula (1), to estimate the center of the lane _{y T.}

y _T = (6A ² ) ⁻¹ (VT) ³ + (2R) ⁻¹ (VT) ² + ψo · VT + yo (1)

Next, in step S3, the control unit 10 estimates the host vehicle future position yo ^* according to the following equation (2).

yo ^* = (1/2) γo · VT ² (2)

In the expressions (1) and (2), T is the forward gaze time [s]. That is, the control unit 10 estimates the center y _T of the lane that the vehicle 1 is running after T seconds, to estimate the center position yo ^* of the vehicle 1 after T seconds.

  Next, in step S4, the control unit 10 sets the correction alarm area threshold value LR on the right side and the correction alarm area threshold value LL on the left side according to the following equations (3) and (4).

LR = Lo + Lc (3)
LL = Lo-Lc (4)

  As is apparent from the equation (3), the right corrected alarm area threshold value LR is larger than the basic alarm area threshold value Lo by the alarm area threshold correction amount Lc. Therefore, as shown in FIG. 3, the right correction alarm area L3, which is an area outside the right side of the lane from the right correction alarm area threshold value LR, is expanded to the lane center side than the right basic alarm area L1. Yes.

  As apparent from the equation (4), the left corrected alarm area threshold LL is a value smaller than the basic alarm area threshold Lo by the alarm area threshold correction amount Lc. Therefore, as shown in FIG. 3, the left corrected alarm area L4, which is the area outside the left side of the lane from the left corrected alarm area threshold value LL, is closer to the left end of the lane than the left basic alarm area L2 (left It is reduced to the white line side.

  Next, in steps S5 and S6, the control unit 10 determines the right lane departure (right departure) and left lane departure (left departure) according to the following equations (5) and (6). That is, if the inequality (5) holds, the control unit 10 determines that the host vehicle 1 may deviate from the lane to the right side, and if the inequality (6) holds, the host vehicle 1 moves the lane to the left side. It is determined that there is a possibility of deviating.

y _T −yo ^* ≧ + {(W / 2) −LR} (5)
^{_{y T -yo * ≦ - {(}} W / 2) -LL} ... (6)

  The right side of inequality (5) is set such that (W / 2)> LR. That is, the value of LR and thus Lc is adjusted so that the right side of inequality (5) does not become 0 (zero) or a negative value. Similarly, the right side of inequality (6) is set such that (W / 2)> LL. That is, the value of LL and thus Lc are adjusted so that the right side of inequality (6) does not become 0 (zero) or a positive value.

Here, as is apparent from FIG. 3, | y _T −yo ^* | is a lateral deviation amount of the center position of the host vehicle 1 with respect to the center of the lane. | (W / 2) −LR | is a lateral distance from the center of the lane to the right correction alarm area L3, that is, “a threshold value for a lateral deviation amount to the right in the traveling direction of the host vehicle”. Is. Since the correction alarm area L3 on the right side is enlarged toward the lane center side (because LR is a value increased from Lo and the value of | (W / 2) −LR | is smaller), an inequality ( 5) is easily established. That is, the right departure is determined at a relatively early timing. On the other hand, | (W / 2) −LL | is the lateral distance from the center of the lane to the left corrected alarm area L4, that is, the “threshold value for the lateral deviation amount to the left in the vehicle traveling direction” Is. Since the correction alarm area L4 on the left side is reduced to the left white line side (because LL is a value reduced from Lo and the value of | (W / 2) −LR | is larger), the inequality (6) is difficult to be established. That is, the left departure is determined at a relatively late timing.

  Next, when it is determined in steps S5 and S6 that the vehicle 1 has deviated to the right or left, in step S7, the control unit 10 avoids the lane departure, that is, the lane center direction (left direction in the case of a right departure). In the case of left departure, the steering device 21 is operated in the right direction). In addition, the alarm device 22 is activated to alert the driver.

  As described above, in step S4, the control unit 10 determines the distance in the vehicle width direction between the vehicle center and the driver seat center than the basic alarm area threshold Lo set to the same value on the right and left sides in the traveling direction of the host vehicle. The right threshold value (| (W / 2) −LR |) where the driver is located is reduced by a value corresponding to (about 0.3 m) (alarm area threshold correction amount Lc), and the left threshold value ( | (W / 2) −LL |) is increased. As a result, the right deviation is determined at a relatively early timing, and the left deviation is determined at a relatively late timing. In short, by correcting the basic warning area threshold Lo set based on the vehicle center reference based on the driver reference, the lateral separation distance between the center of the lane and the vehicle center increases to the same extent on the right and left sides in the traveling direction. The lane departure was determined when the lane departure was determined when the lateral separation distance between the center of the lane and the driver increased to the same extent on the right and left sides in the traveling direction. Thus, the timing when the lane departure is determined is made closer to the driver's feeling.

  Next, the reason why the distance in the vehicle width direction between the vehicle center and the driver seat center is employed as the alarm area threshold correction amount Lc will be described.

  FIG. 4 is a graph showing the distance between the center of the vehicle and the white line when the driver feels the possibility of lane departure in a right-hand drive vehicle, (a) is the test result when the driver is subject A, (b ) Is the test result when the driver is subject B.

  First, consider the case of subject A. As indicated by “◯” in FIG. 4A, when the vehicle is deviated to the left in the lane while traveling at a speed of 60 km / h (angle with the white line on the left: approximately 1.2 ° to 1.6 °) When the center of the vehicle approaches the left white line from approximately 0.6 m to 1.2 m, I feel that the vehicle may depart from the lane to the left. On the other hand, as shown by “Δ” in FIG. 4A, when the vehicle is biased to the right side in the lane under the same conditions, the vehicle center approaches the right white line from about 1.5 m to 1.8 m. , I feel the possibility that the vehicle will deviate right from the lane. In other words, the right side of the vehicle traveling direction feels the possibility of lane departure at an average of about 0.7 m earlier than the left side. This is Case 1.

  Similarly, as indicated by “□” in FIG. 4A, when the vehicle is biased to the left side in the lane while traveling at a speed of 90 km / h (angle with the white line on the left: approximately 0.9 ° to 1.3 °), when the vehicle center approaches the white line on the left from about 1.1 m to 1.4, I feel the possibility that the vehicle will depart from the lane to the left. On the other hand, as shown by “x” in FIG. 4A, when the vehicle is biased to the right side in the lane under the same conditions, the vehicle center approaches the white line on the right from about 1.4 m to 1.8 m. , I feel the possibility that the vehicle will deviate right from the lane. In other words, the right side of the vehicle traveling direction feels the possibility of a lane departure at an average timing about 0.4 m earlier than the left side. This is Case 2.

  Next, consider the case of subject B. As indicated by “◯” in FIG. 4B, when the vehicle is deviated to the left in the lane while traveling at a speed of 60 km / h (angle with the white line on the left: approximately 1.3 ° to 1.7) °) When the vehicle center approaches the white line on the left from about 0.6 m to 1.0 m, the vehicle feels the possibility of deviating from the lane to the left. On the other hand, as indicated by “Δ” in FIG. 4B, when the vehicle is biased to the right side in the lane under the same conditions, the vehicle center approaches the white line on the right from about 1.0 m to 1.3 m. , I feel the possibility that the vehicle will deviate right from the lane. In other words, the right side of the vehicle traveling direction feels the possibility of a lane departure at an average timing about 0.4 m earlier than the left side. This is Case 3.

  Similarly, as indicated by “□” in FIG. 4B, when the vehicle is biased to the left side in the lane while traveling at a speed of 90 km / h (angle with the left white line: approximately 1.0 ° to 1.4 °), when the center of the vehicle approaches the white line on the left from about 0.55 m to 0.85, the vehicle feels the possibility of deviating left from the lane. On the other hand, as shown by “x” in FIG. 4B, when the vehicle is biased to the right side in the lane under the same conditions, the vehicle center approaches the right white line from about 0.95 m to 1.25 m. , I feel the possibility that the vehicle will deviate right from the lane. In other words, the right side of the vehicle traveling direction feels the possibility of a lane departure at an average timing about 0.4 m earlier than the left side. This is Case 4.

  Further discussion will be continued with reference to FIG. 5A and 5B are explanatory diagrams when the driver feels the possibility of lane departure in a right-hand drive vehicle. FIG. 5A shows the distance between the center of the vehicle and the white line, and FIG. 5B shows the relationship between the driver and the white line. Indicates distance.

  As shown in FIGS. 5 (a) and 5 (b), cases 1 to 4 indicate that the driver feels the possibility of lane departure at an earlier timing on the right side in the vehicle traveling direction than on the left side. . For example, in case 1, the right side of the vehicle travel direction senses the possibility of lane departure at an average of about 0.7 m earlier than the left side, and in cases 2 to 4, the possibility of lane departure is about 0.4 m earlier I feel. In this interval, the distance is about 0.6 m, which is twice the distance in the vehicle width direction (about 0.3 m) between the vehicle center and the driver seat center.

  In other words, the subjects A and B have the same lateral distance between the self and the white line on the left and right, in other words, the lateral distance between the self and the lane center is the same on the left and right. When he grows up, he feels the possibility of lane departure. Therefore, the control unit 10 reduces the threshold value (| (W / 2) −LR |) on the right side where the driver is located based on the distance in the vehicle width direction between the vehicle center and the driver seat center, and sets the opposite side. By increasing the left threshold (| (W / 2) −LL |), the threshold can be set reasonably and easily, and the lane departure can be determined at a timing closer to the driver's sense.

(3) as in the above action and the like, the lane deviation prevention support apparatus according to the present embodiment estimates the central y _T of the lane where the vehicle 1 is traveling, to estimate the future position yo ^* of the vehicle 1, estimated lateral deviation amount of the future position yo ^* of the center of the lane y the vehicle with respect to _{T 1 (| y T -yo *} |) is a one having a determined control unit 10 a lane departure when it exceeds a predetermined threshold value, It has the following characteristic configuration.

  That is, the control unit 10 uses the threshold value (| (W / 2) −LR |) for the lateral deviation amount to the right in the traveling direction of the host vehicle and the threshold value (| (W / 2) for the lateral deviation amount to the left as the threshold values. −LL |) is set individually, and the right threshold value (| (W / 2) −LR |) at which the driver is located in the host vehicle 1 is changed to the left threshold value (| (W / 2) − LL |) is set to a smaller value.

  According to this configuration, in the right-hand drive vehicle, the threshold value (| (W / 2) −LR |) for the lateral deviation amount to the right side in the traveling direction of the host vehicle is set to a relatively small value, and the lateral deviation amount to the left side is set. The threshold value (| (W / 2) −LL |) for is set to a relatively large value. Therefore, when the vehicle 1 is deviated from the center of the lane to the right side, the departure from the lane is determined at a relatively early timing (step S5). Conversely, when the vehicle is deviated from the center of the lane to the left side, the timing is relatively late. A lane departure is determined (step S6). As a result, the lane departure is determined at a timing closer to the sense of the driver who is seated on the right side of the vehicle center from when the host vehicle 1 is traveling in the center of the lane.

  In the present embodiment, the control unit 10 corresponds to the distance in the vehicle width direction between the vehicle center and the driver seat center, rather than the basic alarm area threshold Lo set to the same value on the right and left sides in the traveling direction of the host vehicle. The right threshold value (| (W / 2) −LR |) where the driver is located is reduced by the value (alarm area threshold correction amount Lc), and the left threshold value (| (W / 2) −LL |) on the opposite side is reduced. ) Is increased (step S4).

  According to this configuration, based on the distance in the vehicle width direction between the vehicle center and the driver seat center, the right threshold value (| (W / 2) −LR |) where the driver is located and the left threshold value ( Since | (W / 2) −LL |) is set, the threshold can be set reasonably and easily, and the lane departure is determined at a timing closer to the driver's feeling.

In the present embodiment, the control unit 10 estimates the center y _T of the lane where the vehicle 1 after forward fixed point time T [s] is running (step S2), the vehicle 1 after forward fixed point time T [s] Center position yo ^* is estimated (step S3), and lane departure after the forward gaze time T [s] is determined (steps S5 and S6). That is, the control unit 10 predicts a forward fixed point time T [s] the center position of the vehicle 1 after yo ^* from the present time, the predicted vehicle 1 of the center position yo for the central y _T of the lane ^A lane departure is determined when the lateral deviation amount (| y _T -yo ^* |) of ^* exceeds the threshold value.

  According to this configuration, since the lane departure after the forward gaze time T [s] is determined, the lane departure is reliably avoided with a time margin.

  In the present embodiment, an alarm device 22 for alerting the driver and a steering device 21 for steering the host vehicle 1 are provided, and when the lane departure is determined, the control unit 10 The alarm device 22 and the steering device 21 are activated (step S7).

  According to this configuration, when the lane departure is determined, the driver's attention is alerted or the host vehicle 1 is steered in a direction to avoid the lane departure. Therefore, an appropriate measure for avoiding the lane departure is taken. Taken.

  In addition, although the said embodiment was the case of the right-hand drive vehicle, this invention is preferably applicable also to a left-hand drive vehicle.

  The control unit 10 may activate only one of the alarm device 22 and the steering device 21 when a lane departure is determined.

  The alarm device 22 may vibrate the steering handle.

Further, the control unit 10 can be a different approach that is different from the step S2, S3, and estimates the central y _T of the lane where the vehicle 1 is traveling, or even to estimate the future position yo ^* of the vehicle 1 .

1 vehicle 10 control unit (lane center detection means, vehicle center position detection means, determination means, setting means, control means)
11 front sensing camera 12 vehicle speed sensor 13 yaw rate sensor 21 steering device 22 alarm device

Claims (4)

Lane center detection means for detecting the center of the lane in which the host vehicle travels;
A lane departure prevention support apparatus comprising: a determination unit that determines a lane departure when a lateral deviation amount of the center position of the host vehicle with respect to the center of the detected lane exceeds a predetermined threshold,
The threshold value for the lateral deviation amount to the right side in the traveling direction of the host vehicle and the threshold value for the lateral deflection amount to the left side are individually set as the threshold value, and the threshold value on the side where the driver is located in the own vehicle A lane departure prevention support apparatus, comprising setting means for setting a small value. The lane departure prevention support device according to claim 1,
The setting means indicates that the driver is positioned by a value corresponding to the distance in the vehicle width direction between the vehicle center and the driver seat center than a predetermined basic threshold value set to the same value on the right and left sides of the vehicle traveling direction. A lane departure prevention support apparatus characterized in that the threshold value on the side to perform is reduced and the threshold value on the opposite side is increased. In the lane departure prevention support device according to claim 1 or 2,
The determination means predicts the center position of the host vehicle after a predetermined time has elapsed from the present time, and determines a lane departure when a lateral deviation amount of the predicted center position of the host vehicle with respect to the center of the lane exceeds the threshold value. A lane departure prevention support device characterized in that: In the lane departure prevention support device according to any one of claims 1 to 3,
An alarm device to alert the driver,
A steering device for steering the host vehicle;
A lane departure prevention assisting device, comprising: a control unit that activates at least one of the warning device and the steering device when a lane departure is determined by the determination unit.

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