JP2008189148A - Running state detection device - Google Patents

Abstract

A traveling state detection device for detecting a traveling state of a preceding vehicle based on light emitted by a preceding vehicle while distinguishing between light emitted by the preceding vehicle and similar light.
A traveling state detection device 100 captures an image of a vehicle ahead of a vehicle based on image data acquisition means 2 for acquiring image data by photographing the front of the vehicle and image data acquired by the image data acquisition means 2. Based on the determination means 10, the monitoring area determination means 12 for determining a predetermined area in the image data as the monitoring area according to the vehicle type determined by the vehicle type determination means 10, and the change in luminance in the monitoring area determined by the monitoring area determination means 12. Traveling state detecting means 11 for detecting the traveling state of the preceding vehicle. The driving state detection device 100 further includes driving support means 13 that supports driving of the host vehicle according to the driving state of the preceding vehicle detected by the driving state detection means 11.
[Selection] Figure 1

Description

  The present invention relates to a traveling state detection device that detects the traveling state of a preceding vehicle, and in particular, detects the traveling state of a preceding vehicle based on light emitted from a preceding vehicle while distinguishing between light emitted by the preceding vehicle and similar light. The present invention relates to a traveling state detection device.

  2. Description of the Related Art Conventionally, there is known a brake lamp recognition device that captures a traveling direction of a host vehicle with a CCD camera and recognizes that a brake lamp (braking light) of a preceding vehicle is lit based on image data acquired by the photographing. (For example, refer to Patent Document 1).

  The brake lamp recognition device extracts a part having a specific color common to the tail lamp and the brake lamp from the acquired image data, and the brake lamp is turned on when the luminance of the extracted part is equal to or greater than a threshold value. If the luminance of the extracted portion is less than the threshold, it is determined that the tail lamp is only lit.

In addition, when the preceding vehicle is replaced, the brake lamp recognizing device determines whether or not the brake lamp is lit according to each brightness when the tail lamp and the brake lamp are lit in the preceding vehicle after the replacement. Therefore, even if the brightness of the lamps (including tail lamps and brake lamps) of the preceding car after the replacement has changed compared to that of the preceding car before the replacement, the threshold of the preceding car after the replacement It is possible to reliably recognize that the brake lamp is lit.
JP-A-8-221700

  However, since the brake lamp recognition device described in Patent Document 1 determines whether or not the brake lamp of the preceding vehicle is lit based on the luminance of the portion having the specific color, the light emitted from the preceding vehicle (brake lamp) Cannot be distinguished from the similar light (the brake light of the preceding car that travels further ahead of the preceding car, the illumination of the downtown area, the headlight of the oncoming car, sunlight, etc.) and the brake light of the preceding car lights You may mistakenly recognize this.

  Even if a specific color is detected in a part where the brake lamp cannot exist, the useless process of monitoring the luminance of that part is continued in order to determine whether or not the brake lamp is lit. There is a problem of end.

  In view of the above, the present invention has an object to provide a traveling state detection device that detects the traveling state of a preceding vehicle based on the light emitted by the preceding vehicle while distinguishing between the light emitted by the preceding vehicle and the similar light. And

  In order to achieve the above object, a traveling state detection device according to a first aspect of the present invention is based on image data acquisition means for acquiring image data by photographing the front of a vehicle, and image data acquired by the image data acquisition means. Vehicle type determination means for determining the vehicle type of the preceding vehicle, monitoring area determination means for determining a predetermined area in the image data as a monitoring area according to the vehicle type determined by the vehicle type determination means, and the monitoring area determination means And a traveling state detecting means for detecting the traveling state of the preceding vehicle based on the image information in the monitoring area.

  The second invention is a traveling state detection device according to the first invention, further comprising distance data acquisition means for acquiring a distance between the host vehicle and a preceding vehicle, wherein the vehicle type determination means includes the The vehicle type of the preceding vehicle is determined based on at least one of the image data acquired by the image data acquisition means and the distance data acquired by the distance data acquisition means.

  Moreover, 3rd invention is the driving | running | working state detection apparatus which concerns on 1st or 2nd invention, Comprising: The said image data acquisition means is a stereo camera, It is characterized by the above-mentioned.

  According to a fourth aspect of the present invention, there is provided a traveling state detection apparatus according to any one of the first to third aspects, wherein the image data acquisition means is an infrared camera.

  The fifth aspect of the present invention is a traveling state detection device according to any one of the first to fourth aspects of the present invention, which supports driving of the host vehicle according to the traveling state of the preceding vehicle detected by the traveling state detection means. The vehicle is further provided with driving support means.

  With the above-described means, the present invention can provide a traveling state detection device that detects the traveling state of the preceding vehicle based on the light emitted by the preceding vehicle while distinguishing between the light emitted by the preceding vehicle and the similar light.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration example of a traveling state detection device according to the present invention. A traveling state detection device 100 is an in-vehicle device for detecting a traveling state of a preceding vehicle, and includes a control unit 1 and a camera 2. The inter-vehicle distance sensor 3, the storage device 4, the sound output device 5, and the brake control device 6.

  The control unit 1 is a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an NVRAM (Non-Volatile Random Access Memory), and the like. Necessary information is acquired from the camera 2, the inter-vehicle distance sensor 3, and the storage device 4 via an in-vehicle network such as a LIN (Local Interconnect Network), and after performing various calculations based on the acquired information, the audio output device 5 Then, a control signal is transmitted to the brake control device 6 to control these devices.

  In addition, the control unit 1 stores programs corresponding to the vehicle type determination unit 10, the traveling state detection unit 11, the monitoring area determination unit 12 and the driving support unit 13 in the NVRAM, and develops these programs on the RAM for handling. CPU is caused to execute the process.

  The camera 2 is an image data acquisition means for capturing an image of the periphery of the vehicle and acquiring image data of the periphery of the vehicle. For example, a CCD (Charge-Coupled Device) color camera installed near a room mirror in the vehicle interior And the image data ahead of the own vehicle is acquired.

  The camera 2 may be a stereo camera capable of measuring the distance to the subject, an infrared camera capable of photographing at night, or an infrared stereo camera having both functions. Good.

  The camera 2 may switch the color camera (normal mode) to the infrared camera (night vision mode) when lighting of a headlight or the like is started.

  The inter-vehicle distance sensor 3 is distance data acquisition means for acquiring distance data to objects around the own vehicle, and is, for example, a millimeter wave radar installed in the front grille. Measure the distance between the cars. The inter-vehicle distance sensor 3 may be an infrared laser radar or an ultrasonic sensor.

  The storage device 4 is a device for storing information required by the traveling state detection device 100. For example, the storage device 4 is a non-volatile storage medium such as a hard disk or a flash memory. Have

  The vehicle-specific lamp information DB 40 is a database that stores information on the position and size of lamps (hereinafter referred to as “lamp information”) for each vehicle type such as a large vehicle, a normal passenger car, or a motorcycle.

  The lights include reverse lights, emergency flashing indicators, turn indicators, auxiliary turn indicators, brake lights, auxiliary brake lights, large rear reflectors, rear upper end lights, rear fog lights, parking lights, tail lights or There are number lights etc.

  The voice output device 5 is a device for outputting voice, for example, an in-vehicle speaker, and outputs a voice message, a warning sound, or the like according to a control signal output from the control unit 1.

  The brake control device 6 is a device for controlling the braking force by the brake. For example, the brake control device 6 drives a motor or an actuator in accordance with a control signal output from the control unit 1 to automatically generate the braking force by the brake. Control the brake assist force when the brake is operated.

  Next, various units included in the control unit 1 will be described.

  The vehicle type determination means 10 is a means for determining the vehicle type of the vehicle on the image. For example, the image data obtained by the camera 2 is subjected to image processing such as binarization processing and edge extraction processing to obtain the image of the preceding vehicle. (Including an entire image and a partial image of the preceding vehicle; hereinafter referred to as “preceding vehicle image”), and the extracted preceding vehicle image and a registered image of the vehicle type stored in advance in the storage device 4 (for each vehicle type). The vehicle type of the preceding vehicle is determined by comparing the entire image and the partial image) with pattern matching.

  Further, when the camera 2 is a stereo camera, the vehicle type determination means 10 derives the size or shape of the preceding vehicle based on the distance data of the preceding vehicle acquired by the camera 2, and determines the vehicle type of the preceding vehicle from the derived size or shape. The vehicle type of the preceding vehicle may be determined based on the preceding vehicle image and the distance data acquired by the camera 2.

  Further, the vehicle type determination means 10 uses the distance data of the preceding vehicle acquired by the inter-vehicle distance sensor 3 instead of the distance data of the preceding vehicle acquired by the camera 2 or in addition to the distance data of the preceding vehicle. The size or shape of the vehicle may be derived, and the vehicle type of the preceding vehicle may be determined from the derived size or shape.

  Further, the vehicle type determination means 10 may determine the vehicle type of the preceding vehicle by reading the number of the license plate from the acquired image data, and using the existing determination technology such as a neural network, the acquired image data and distance The vehicle type of the preceding vehicle may be determined based on the data.

  The vehicle type determination means 10 executes the vehicle type determination of the preceding vehicle every time the control unit 1 detects the preceding vehicle based on the image data acquired by the camera 2 or the distance data acquired by the inter-vehicle distance sensor 3. Then, the determination result is recorded in the storage device 4.

  The traveling state detection unit 11 is a unit for detecting the traveling state of the preceding vehicle. For example, a monitoring area (for example, a high-mount brake lamp (braking auxiliary light) of the preceding vehicle) is located in the image data acquired by the camera 2. The change in the image information (luminance, color tone, etc.) of the vehicle is monitored, and the brake of the preceding vehicle was operated as if the high-mount brake lamp was lit when the luminance exceeded the threshold. Is detected.

  In addition, the driving state detection means 11 performs the brake operation only when the luminance values in the plurality of monitoring areas increase simultaneously (for example, when the left and right brake lamps of the preceding vehicle are lit simultaneously). You may make it detect.

  This is because a plurality of brake lamps in one preceding vehicle are normally lit at the same time, and therefore it can be estimated that the brake lamps are not lit when the brightness values in a plurality of monitoring areas do not increase simultaneously. This is because the detection accuracy of the running state can be improved by making the detection conditions stricter.

  Note that the traveling state detection unit 11 periodically calculates, for example, the average luminance, intermediate luminance, maximum luminance, minimum luminance, or the like of all pixels included in the monitoring area as the luminance value of the monitoring area (for example, at intervals of one second). To do.

  In addition, the running state detection unit 11 compares the brightness of all the pixels included in the monitoring area with a threshold value, and the ratio of the number of pixels whose brightness value is equal to or greater than the threshold value to the total number of pixels is a predetermined ratio ( For example, when it exceeds 50%, it may be detected that the lights in the monitoring area are lit.

  In addition, the traveling state detection unit 11 determines, for example, an area having a specific color in the image data (for example, red for a brake lamp, orange for a hazard lamp (emergency blinking display lamp), etc.) as a monitoring area. The threshold value may be continuously updated based on the value when the luminance is low and the value when the luminance is high while learning the luminance change of the monitoring area.

  Even if the preceding vehicle has changed and the brightness of the lamps (including the tail lamp and brake lamp) of the preceding vehicle after the replacement has changed compared to that of the preceding vehicle before the replacement, the preceding vehicle after the replacement This is to ensure that it is possible to reliably recognize that the brake lamp is turned on.

  In this case, the traveling state detection unit 11 records the luminance value in each monitoring area in the RAM provided in the control unit 1, and manages the luminance value in each monitoring area recorded in the RAM in chronological order. In a high luminance state (for example, a state in which a brake lamp is lit), a medium luminance state (for example, a state in which a tail lamp is lit), or a low luminance state (for example, a state in which the lamp is turned off) ) Is continuously updated (in this case, two threshold values are prepared).

  The monitoring area determination means 12 is a means for determining a monitoring area (an area in which the driving state detection means 11 monitors the brightness of the preceding vehicle so as to detect the driving state of the preceding vehicle). The means 10 determines the vehicle type of the preceding vehicle in the image data acquired by the camera 2, reads the lighting information corresponding to the determined vehicle type from the vehicle-specific lighting information DB 40, and determines the position and size of the monitoring area.

  In the lamp information, for example, the position and size of the lamp are registered as a relative position and size with respect to the preceding vehicle image (for example, the width of the preceding vehicle image (expressed in pixels from the upper left corner of the preceding vehicle image). )) To the right, and the pixel at the position moved 3/4 below the height of the preceding vehicle image (expressed in pixels) is the center position of the lights. The size consisting of one-fourth the width of the vehicle image and one-fifth the height of the preceding vehicle image is registered as the size of the lights.), The preceding vehicle image acquired by the camera 2 If it is small (meaning that the inter-vehicle distance is large), the monitoring area is also set small according to the size of the preceding vehicle image.

  The driving support means 13 is a means for supporting the driving of the host vehicle based on the traveling state of the preceding vehicle detected by the traveling state detecting means 11. For example, the traveling state detecting means 11 detects a brake operation in the preceding vehicle. In this case, a control signal is transmitted to the voice output device 5 to output a voice message “attention ahead” from the vehicle-mounted speaker.

  The driving support means 13 sends a control signal to the brake control device 6 when the traveling state detection means 11 detects a brake operation in the preceding vehicle so that the braking force by the brake is automatically generated, The brake assist force may be strengthened, or the gear ratio may be changed to generate an engine brake.

  The driving support means 13 calculates the relative speed or the relative acceleration of the preceding vehicle with respect to the own vehicle based on the image data acquired by the camera 2 or the distance data acquired by the inter-vehicle distance sensor 3 when strengthening the brake assist force. The brake assist force may be determined according to the calculated relative speed or relative acceleration.

  2A and 2B are rear views of various vehicles. FIG. 2A is a rear view of a large vehicle, FIG. 2B is a rear view of a normal passenger car, and FIG. 2C is a rear view of a motorcycle. Respectively.

  FIG. 3 is a diagram showing the position and size of the monitoring area corresponding to various vehicles, and FIG. 3A is a preceding vehicle image of a large vehicle determined to be present in the image data by the vehicle type determination means 10. The size R1 is indicated by a one-dot chain line, and the monitoring areas F10 and F11 corresponding to the large vehicle determined by the monitoring area determining means 12 with reference to the vehicle type lighting information DB 40 are indicated by solid lines.

  Similarly, FIG. 3B shows the preceding vehicle image size R2 of the ordinary passenger car by a one-dot chain line frame, and shows the monitoring areas F20 to F22 corresponding to the ordinary passenger car by a solid line frame.

  FIG. 3C shows a preceding vehicle image size R3 of the motorcycle by a one-dot chain line, and shows a monitoring area F30 corresponding to the motorcycle by a solid line frame.

  The monitoring area determining means 12 actively determines the monitoring area according to the vehicle type of the preceding vehicle determined by the vehicle type determining means 10, but conversely, the predetermined area is excluded from the area to be monitored. The monitoring area may be determined passively.

  FIG. 4 is a diagram showing the position and size of the monitoring area when there is a preceding vehicle and a preceding vehicle, and shows that the preceding vehicle is a motorcycle and the preceding vehicle is a normal passenger car.

  In this case, the vehicle type determination unit 10 determines that the preceding vehicle is a motorcycle based on the output of the inter-vehicle distance sensor 3 and acquires the preceding vehicle image size R3, and the monitoring region determination unit 12 determines the preceding vehicle image size R3. And the monitoring area F30 is determined based on the lighting information in the vehicle-specific lighting information DB 40.

  As a result, the traveling state detection device 100 is configured so that the traveling state detection unit 11 does not turn on the brake lamp of the motorcycle in the monitoring area F30 even when the braking lamp of the ordinary passenger car that is the preceding vehicle is turned on. The driving support by the driving support means 13 is not started assuming that no change is seen in the running state of the motorcycle.

  Thereby, the traveling state detection apparatus 100 can reliably prevent erroneous detection of the traveling state of the preceding vehicle due to the light emitted from the preceding vehicle.

  Next, a process (hereinafter referred to as “monitoring area determination process”) in which the traveling state detection apparatus 100 determines a monitoring area will be described with reference to FIG. FIG. 5 is a flowchart showing the flow of the monitoring area determination process.

  First, the control unit 1 of the traveling state detection device 100 determines whether there is a preceding vehicle based on the image data acquired by the camera 2 or the distance data acquired by the inter-vehicle distance sensor 3 (step S1).

  When it determines with a preceding vehicle not existing (NO of step S1), the control part 1 complete | finishes a monitoring area | region determination process. This is because it is not necessary to monitor the traveling state of the preceding vehicle.

  When it is determined that there is a preceding vehicle (YES in step S1), the control unit 1 determines the vehicle type of the preceding vehicle by the vehicle type determination unit 10 (step S2) and stores the previous determination result by the vehicle type determination unit 10. Read from the device 4 (step S3).

  Thereafter, the control unit 1 compares the current determination result with the previous determination result, and confirms whether or not the current determination is the first determination (step S4).

  When it is confirmed that the previous determination result does not exist and is the first determination (YES in Step S4), the control unit 1 refers to the vehicle-specific lamp information DB 40 in the storage device 4 by the monitoring area determination unit 12. Then, the monitoring area corresponding to the vehicle type determined this time is determined as the monitoring area to be actually used (step S5).

  Then, the control part 1 starts the brake determination process mentioned later (step S6), and complete | finishes the monitoring area | region determination process.

  When it is confirmed that the previous determination result exists and is not the first determination (NO in step S4), the control unit 1 determines whether or not the vehicle type by the current determination is different from the vehicle type by the previous determination. (Step S7).

  When it is determined that the vehicle type determined by the current determination is different from the vehicle type determined by the previous determination (YES in step S7), the control unit 1 refers to the vehicle type lighting information DB 40 in the storage device 4 by the monitoring area determination unit 12. Then, after updating the current monitoring area with the monitoring area corresponding to the vehicle type determined this time (step S8), a brake determination process described later is started (step S6), and the monitoring area determination process is ended.

  When it is determined that the vehicle type determined by the current determination and the vehicle type determined by the previous determination are the same (NO in step S7), the control unit 1 uses the current monitoring area as it is without updating the monitoring area. Then, a brake determination process described later is started (step S6), and the monitoring area determination process is ended.

  Next, with reference to FIG. 6, a process (hereinafter referred to as “brake determination process”) in which the traveling state detection device 100 determines whether or not there is a brake operation in the preceding vehicle will be described. FIG. 6 is a flowchart showing the flow of the brake determination process.

  First, the controller 1 of the traveling state detection device 100 determines the inter-vehicle distance L between the host vehicle and the preceding vehicle based on image data acquired by the camera 2 (stereo camera) or distance data acquired by the inter-vehicle distance sensor 3. And the inter-vehicle distance L is compared with the threshold value α (step S10).

  When the inter-vehicle distance L is equal to or greater than the threshold value α (NO in step S10), the control unit 1 determines that the influence of the traveling state of the preceding vehicle on the host vehicle is small and does not start driving support by the driving support means 13 without starting driving support. The determination process is terminated.

  On the other hand, when the inter-vehicle distance L is less than the threshold value α (YES in step S10), the control unit 1 acquires the luminance K of the monitoring area determined by the monitoring area determination unit 12, and determines the luminance K and the threshold value β. Compare (step S11).

  When the brightness K is less than the threshold value β (NO in step S11), the control unit 1 detects a state in which the preceding vehicle continues to travel without brake operation by the traveling state detection unit 11, and the traveling state of the preceding vehicle The brake determination process is terminated without starting the driving assistance by the driving assistance means 13 on the assumption that the influence of the vehicle on the own vehicle is small.

  On the other hand, when the brightness K is equal to or higher than the threshold value β (YES in step S11), the control unit 1 detects the state in which the brake operation is performed on the preceding vehicle by the traveling state detection unit 11, and has an influence on the own vehicle. If not, the driving support by the driving support means 13 is started (step S12).

  Thereafter, the control unit 1 causes the driving support means 13 to transmit a control signal to the audio output device 5 to output a caution message such as “caution ahead” or “please decelerate”, or cause the brake control device 6 to output a control signal. Is transmitted to automatically decelerate the vehicle or increase the brake assist force to end the brake determination process.

  With the above configuration, the traveling state detection device 100 more strictly determines the monitoring area according to the vehicle type of the preceding vehicle, so that the detection accuracy of the traveling state of the preceding vehicle is improved, and erroneous detection or detection omission of the traveling state is prevented. As a result, the traveling safety of the host vehicle can be improved.

  Moreover, since the driving | running | working state detection apparatus 100 determines the monitoring area | region according to the vehicle type of a preceding vehicle, after measuring the inter-vehicle distance between the own vehicle and a preceding vehicle, it is similar to the light which a preceding vehicle emits, and its light For example, even if the preceding vehicle is a motorcycle, the preceding vehicle is a normal passenger car or a large vehicle, and a large number of lights overlap or confuse, The traveling state of the motorcycle can be detected with high accuracy.

  Moreover, since the driving | running | working state detection apparatus 100 limits a monitoring area | region to a necessary and sufficient area | region, it can allocate a resource intensively to a required process, preventing a useless process.

  In addition, since the traveling state detection device 100 centrally monitors a limited monitoring area until it becomes necessary and sufficient, even if the visibility of the preceding vehicle is poor due to a high beam or dense fog of an oncoming vehicle, The detection accuracy can be improved, and erroneous detection and detection omission of the running state can be prevented. As a result, the traveling safety of the host vehicle can be improved.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, it is detected that the brake operation has been performed on the preceding vehicle based on the brightness of the brake lamp of the preceding vehicle in the monitoring area determined for each vehicle type. The lane change of the preceding vehicle may be detected in advance based on the brightness of the direction indicator.

  In this case, the traveling state detection device 100 detects the traveling state of not only a preceding vehicle traveling in the same lane as the own vehicle but also a preceding vehicle traveling in a lane different from the own vehicle.

  Further, the traveling state detection device 100 may detect in advance a right or left turn of the preceding vehicle based on the brightness of the blinker lamp of the preceding vehicle in the monitoring area, or based on the brightness of the hazard lamp of the preceding vehicle in the monitoring area. Thus, it may be detected that the preceding vehicle has approached a traffic jam.

  Further, in the above-described embodiment, the driving state detection device 100 transmits a control signal to the voice output device 5 and outputs a voice message from the vehicle-mounted speaker when the driving state detection unit 11 detects a brake operation in the preceding vehicle. To alert the driver, but display a warning message on a display device such as a liquid crystal display or head-up display in the navigation system, wind up the seat belt, or vibrate the steering wheel or seat. It may be possible to call the attention of the person.

It is a figure which shows the structural example of the driving | running | working state detection apparatus which concerns on this invention. It is a figure which shows the rear view of various vehicles. It is the figure (the 1) which shows the position and size of the monitoring area | region corresponding to various vehicles. It is the figure (the 2) which shows the position and size of the monitoring area | region corresponding to various vehicles. It is a flowchart which shows the flow of a monitoring area | region determination process. It is a flowchart which shows the flow of a brake determination process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control part 2 Camera 3 Inter-vehicle distance sensor 4 Memory | storage device 5 Audio | voice output device 6 Brake control apparatus 10 Vehicle type determination means 11 Running condition detection means 12 Monitoring area | region determination means 13 Driving support means 40 Vehicle type lamp information DB
100 Traveling state detection device F10, F11, F20 to F22, F30 Monitoring area R1 to R3 Preceding vehicle image size

Claims (5)

Image data obtaining means for photographing the front of the vehicle and obtaining image data;
Vehicle type determination means for determining the vehicle type of the preceding vehicle based on the image data acquired by the image data acquisition means;
Monitoring area determining means for determining a predetermined area in the image data as a monitoring area according to the vehicle type determined by the vehicle type determining means;
A traveling state detection unit that detects a traveling state of a preceding vehicle based on image information in the monitoring region determined by the monitoring region determination unit;
A traveling state detection device comprising: It further comprises distance data acquisition means for acquiring the distance between the host vehicle and the preceding vehicle,
The vehicle type determination unit determines a vehicle type of a preceding vehicle based on at least one of the image data acquired by the image data acquisition unit and the distance data acquired by the distance data acquisition unit.
The traveling state detection device according to claim 1. The image data acquisition means is a stereo camera;
The traveling state detection device according to claim 1 or 2. The image data acquisition means is an infrared camera;
The traveling state detection device according to any one of claims 1 to 3. Driving assistance means for assisting driving of the host vehicle according to the traveling state of the preceding vehicle detected by the traveling state detection means;
The traveling state detection device according to any one of claims 1 to 4.

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