JP2009205608A - Lane recognizing device, and program for recognizing vehicle and lane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lane recognizing device, and a program for recognizing a vehicle and lane capable of shortening a period in which recognition of a relative position of the vehicle and a lane mark is inhibited while securing reliability of lane mark detection. <P>SOLUTION: The lane recognizing device comprises a lane mark position recognizing means 13, and a reliability restoration determination value setting means 12. The lane mark position recognizing means 13 cancels recognition of the relative position when a first lane mark detection rate as an average detection rate of lane marks by a lane mark detection means 11 in a plurality of predetermined immediate cycles is not more than a reliability degradation determination value, and then, restarts the recognition of the relative position when the first lane mark detection rate reaches more than a reliability restoration determination value higher than the reliability degradation determination value. The reliability restoration determination value setting means 12 sets the reliability restoration determination value depending on a form of a change of a local detection rate of the lane mark by the lane mark detection means 11 in the plurality of the predetermined immediate cycles when the first lane mark detection rate drops to not more than the reliability degradation determination value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lane recognition device, a vehicle, and a lane recognition program for detecting a lane mark that divides a road lane and recognizing a relative position between the vehicle and the lane mark.

Conventionally, road images are acquired at predetermined intervals by a camera mounted on a vehicle, and lane mark image portion candidates detected from each road image are collected for a short period of time, and the camera coordinates of each image portion are implemented. There has been proposed a technique for calculating a relative distance between a lane mark and the host vehicle by converting to spatial coordinates (for example, see Non-Patent Document 1).
Kenichi Kajita, Kiyozumi Kajiura, Tetsuo Ikeda, “Development of White Line Recognition System in Lane Keep Assist System”, HONDA R & D Technical Review Vol. 12 No. 1, April 2000

  In the above-described conventional technology, candidates for the image portion of the lane mark detected from the road images acquired at successive predetermined intervals are collected for a short period of time and converted into real space coordinates. Recognizes real space position. In this case, as shown in FIG. 6, an average lane mark detection rate in the immediately preceding predetermined period is generally employed as a measure of the reliability of recognition of the real space position of the lane mark. .

6, the result of the lane mark detection processing is executed at predetermined cycle T _10, when the lane mark is detected shown in ○, and indicates when the lane mark is not detected in ×. Also, when the reliability of the lane mark detection is judged to be high and the relative position between the lane mark and the vehicle is recognized, a circle is shown, and the lane mark detection reliability is judged to be low. The case where the recognition of the relative position to the vehicle is stopped is indicated by x.

Then, the reliability of lane mark detection is determined when the number of periods in which lane marks are detected is equal to or greater than m in the period period (t _{11 to} t _p1 ) for n periods immediately before the determination time point t _p1 . It is determined that the reliability of lane mark detection is high, and the relative position between the lane mark and the vehicle is recognized.

In this case, when switching from a state where no lane mark is detected (a state where x continues, to t ₁₄ ) to a state where a lane mark is detected (shift from x to ○, t ₁₅ to), at least m Until the time corresponding to × T ₁₀ has elapsed, it is not determined that the reliability of lane mark detection has increased, and therefore, recognition of the relative position between the lane mark and the vehicle cannot be started.

  Therefore, for example, when a vehicle passes through an intersection or travels at a branch / junction point at an interchange, the vehicle travels temporarily in a place where no lane mark is laid, and the reliability of lane mark detection is improved. When the recognition of the relative position between the lane mark and the vehicle is stopped due to the decrease, the lane mark detection is judged to be highly reliable even if the lane mark is restored to the laid state after that. It takes a certain amount of time.

  As a result, there is an inconvenience that the period during which the steering assist control for maintaining the lane or the deviation warning control from the lane cannot be performed is based on the recognition result of the relative position between the lane mark and the vehicle. .

  The present invention has been made in view of the above background, and the period during which the recognition of the relative position between the lane mark and the vehicle is prohibited can be shortened while ensuring the high reliability of lane mark detection. An object is to provide a lane recognition device, a vehicle, and a lane recognition program.

  The present invention has been made to achieve the above object, and a lane recognition device according to the present invention is a lane mark for distinguishing road lanes from a road image around the vehicle imaged by a camera mounted on the vehicle. Lane mark detecting means for executing a process for detecting the lane mark and a relative position between the lane mark and the vehicle based on a lane mark detection result by the lane mark detecting means, When the first lane mark detection rate, which is the average detection rate of lane marks by the lane mark detection means in the predetermined period, is less than or equal to a predetermined reliability decrease determination value, the recognition of the relative position is stopped. After that, when the first lane mark detection rate becomes equal to or higher than the reliability recovery determination value higher than the reliability decrease determination value, the level at which the recognition of the relative position is resumed. Mark position recognizing means, and when the first lane mark detection rate is equal to or lower than the reliability decrease determination value, the lane mark local detection rate by the lane mark detection means in the plurality of immediately preceding predetermined periods And a reliability recovery determination value setting means for setting the reliability recovery determination value according to the change mode.

  In the present invention, when the first lane mark detection rate is equal to or lower than the reliability decrease determination value, the local detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before is determined. Although the details of the mode of change will be described later, it reflects to some extent the reliability recovery status of the subsequent lane mark detection. Accordingly, the reliability recovery determination value setting means is configured to use the lane mark detection means in the plurality of immediately preceding predetermined cycles when the first lane mark detection rate is equal to or lower than the reliability decrease determination value. The reliability recovery determination value is set in accordance with the manner in which the local detection rate changes.

  As a result, as compared with the case where the reliability recovery determination value is set to a constant value, the reliability of lane mark detection is ensured, and the relative lane mark by the lane mark position recognition unit is compared with the vehicle. A period until the position recognition is restarted can be shortened.

  The reliability recovery determination value setting means may detect the lane mark in the first half period of the plurality of the predetermined cycles immediately before when the first lane mark detection rate is equal to or lower than the reliability decrease determination value. Whether the second lane mark detection rate, which is the lane mark detection rate by the means, is higher than a predetermined level than the third lane mark detection rate, which is the lane mark detection rate by the lane mark detection means in the second half period. When the second lane mark detection rate is higher than the third lane mark detection rate by the predetermined level or more, the reliability recovery determination value is set to the first reliability recovery determination value. When the second lane mark detection rate is not higher than the predetermined level by the second lane mark detection rate, the reliability recovery determination value is referred to as the first reliability recovery determination value. And setting to a higher second reliability recovery determination value.

  In the present invention, when the first lane mark detection rate becomes equal to or lower than the reliability decrease determination value, the lane mark by the local lane mark detection means in the first half period of the plurality of the predetermined periods immediately before is determined. When the second lane mark detection rate that is the detection rate of the second lane mark is higher than the third lane mark detection rate that is the detection rate of the lane mark by the local lane mark detection means in the second half period, by a predetermined level or more, Since the local detection rate of the lane mark is rapidly decreasing, it can be assumed that the lane mark is suddenly interrupted.

  In this way, the lane mark is suddenly interrupted when there is a high possibility that the lane mark is temporarily traveling in a place where the lane mark is not laid (intersection, intersection / intersection, etc.). In this case, after passing through such a place, it is expected that the vehicle will promptly return to the situation where it travels on the road where the lane mark is laid. Therefore, in this case, a lane mark is detected by setting the reliability recovery determination value to the lower first reliability recovery determination value by the reliability recovery determination value setting means. When this happens, the recognition of the relative position between the lane mark and the vehicle by the lane mark position recognizing means can be resumed promptly.

  Even if the reliability recovery judgment value is set to a low value in this way, the situation of traveling on the road where the lane mark is laid continues due to the passage of an intersection, etc., and the lane mark detection means detects the lane mark. Since the reliability is assumed to be high, it can be excluded to ensure the high reliability of lane mark detection.

  On the other hand, when the second lane mark detection rate is not higher than the predetermined level by more than the third lane mark detection rate, a situation in which the lane mark is difficult to detect continues as when the lane mark is blurred. Can be assumed.

  The situation in which the lane mark is in such a manner that it is difficult to detect the lane mark is expected to continue, for example, until the lane mark repair is completed. Therefore, in this case, the reliability of the lane mark detection is low by setting the reliability recovery determination value to the higher second reliability recovery determination value by the reliability recovery determination value setting means. In this situation, the recognition of the relative position between the lane mark and the vehicle by the lane mark position recognition unit can be prevented from being resumed, and the reliability of the recognition of the relative position can be maintained.

  The reliability recovery determination value setting means sets the first lane mark detection rate within the predetermined time after setting the reliability recovery determination value to the first reliability recovery determination value. The reliability recovery determination value is set to the second reliability recovery determination value when the reliability recovery determination value is not greater than or equal to.

  In the present invention, after the reliability recovery determination value is set to the first reliability recovery determination value by the reliability recovery determination value setting means, the first lane mark detection rate is set to the first reliability within a predetermined time. When the reliability recovery judgment value of 1 or more is not reached, it can be assumed that the situation where it is difficult to detect the lane mark by the lane mark detection means continues. Therefore, in this case, by setting the reliability recovery determination value to the second reliability recovery determination value higher than the first reliability recovery determination value by the reliability recovery determination value setting means, It is possible to prevent the recognition of the relative position between the lane mark and the vehicle by the lane mark position recognition unit in a situation where the reliability of the lane mark detection is low, and maintain the reliability of the recognition of the relative position. it can.

  Next, the vehicle according to the present invention executes a process for detecting a lane mark that divides a road lane from a camera and an image of a road around the host vehicle captured by the camera at predetermined intervals. Based on the detection result of the lane mark by the detection means and the lane mark detection means, the relative position between the lane mark and the host vehicle is recognized, and the average of the lane marks by the lane mark detection means in a plurality of immediately preceding predetermined periods When the first lane mark detection rate, which is a typical detection rate, falls below a predetermined reliability decrease determination value, the recognition of the relative position is stopped, and then the first lane mark detection rate is Lane mark position recognition means for recognizing the relative position when the reliability recovery determination value is higher than the reliability decrease determination value, and the first lane mark detection rate When the reliability drop determination value is equal to or lower than the reliability decrease determination value, the reliability recovery determination value is set according to a mode of a change in the local detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before. And a reliability recovery judgment value setting means for setting.

  According to the present invention, similarly to the lane recognition device of the present invention described above, the reliability recovery determination value setting means is configured such that when the first lane mark detection rate is equal to or lower than the reliability decrease determination value. The reliability recovery determination value is set in accordance with the change in the local detection rate of the lane mark by the lane mark detection means in the plurality of immediately preceding predetermined cycles.

  As a result, as compared with the case where the reliability recovery determination value is set to a constant value, the reliability of lane mark detection is ensured, and the relative lane mark by the lane mark position recognition unit is compared with the vehicle. A period until the position recognition is restarted can be shortened.

  Further, the lane recognition program of the present invention uses a computer having means for accessing data of a captured image of a camera mounted on a vehicle to determine a lane of the road from an image of a road around the vehicle captured by the camera. A process for detecting the lane mark to be classified is executed at predetermined intervals, and based on the detection result of the lane mark by the lane mark detection means, the relative position between the lane mark and the vehicle is recognized, When the first lane mark detection rate, which is the average detection rate of the lane mark by the lane mark detection unit in the plurality of immediately preceding predetermined cycles, is less than or equal to a predetermined reliability decrease determination value, the relative position When the first lane mark detection rate becomes equal to or higher than the reliability recovery determination value higher than the reliability decrease determination value Lane mark position recognizing means for recognizing the relative position, and the computer, when the first lane mark detection rate is equal to or lower than the reliability decrease determination value, in a plurality of immediately preceding predetermined cycles. The lane mark detection unit functions as a reliability recovery determination value setting unit that sets the reliability recovery determination value in accordance with a change in the local detection rate of the lane mark.

  By causing the computer to execute the lane recognition program of the present invention, the lane recognition device of the present invention and the lane mark detection means, the lane mark position recognition, and the reliability recovery determination value setting means of the vehicle described above. Can be configured.

  An example of an embodiment of the present invention will be described with reference to FIGS. Referring to FIG. 1, a lane recognition device 10 is used by being mounted on a vehicle 1 (vehicle of the present invention), and classifies a traveling lane from a road image captured by a camera 2 that images the front of the vehicle 1. For this purpose, the lane mark laid on the road is detected and the relative position between the lane mark and the vehicle 1 is recognized.

  Further, data on the relative position between the lane mark recognized by the lane recognition device 10 and the vehicle 1 is output to an ECU (Electronic Control Unit) 20 of the vehicle 1. Based on the relative position between the lane mark and the vehicle 1, the ECU 20 performs lane maintenance control for assisting driving of the steering so that the vehicle 1 is maintained in the traveling lane, and a situation in which the vehicle 1 is likely to deviate from the traveling lane. When this happens, lane departure warning control is performed to give a warning (by voice output from a speaker (not shown), etc.).

  Next, referring to FIG. 2, the lane recognition device 10 detects a lane mark (white line, yellow line, cat's eye, Bots Dots, etc.) from the road image ahead of the vehicle imaged by the camera 2. By detection means 11, reliability recovery determination value setting means 12 for setting a reliability recovery determination value for determining that the reliability of lane mark detection by lane mark detection means 11 has been recovered, and lane mark detection means 11 Lane mark position recognition means 13 for determining the reliability of lane mark detection and recognizing the relative position between the lane mark and the vehicle when the lane mark detection reliability is high, and whether or not the lane mark detection means 11 detects lane mark detection And a ring buffer 14 for storing data indicating.

  The lane recognition device 10 is an electronic unit configured by a microcomputer (corresponding to the computer of the present invention) or the like, and by causing the microcomputer to execute the lane recognition program of the present invention, the microcomputer It functions as mark detection means 11, reliability recovery determination value setting 12, and lane mark position recognition means 13.

  The lane mark detection means 11 captures the front of the vehicle with the camera 2 at every control period (corresponding to a predetermined period of the present invention) of the lane recognition device 10 to acquire a road image, and the edge point extracted from the image is detected. A straight line extraction process such as a Hough transform is performed to detect a lane mark image portion. As shown in FIG. 5A, the lane mark detection result (with lane mark / without lane mark) in the immediately preceding n control cycles has a size n (n = 30 in this embodiment). The data is sequentially stored in the ring buffer 14.

  The lane mark position recognizing unit 13 converts the camera coordinates of the image portion of the lane mark detected by the lane mark detecting unit 11 into real space coordinates, and determines the relative position between the vehicle 1 and the lane mark in the real space. recognize.

  Further, the lane mark position recognition unit 13 determines the reliability of lane mark detection by the lane mark position detection unit 11. Only when it is determined that the reliability of the lane mark detection is high, the relative position between the vehicle 1 and the lane mark based on the detection result of the lane mark by the lane mark position detection means 11 is recognized, and the reliability of the lane mark detection. When it is determined that the lane mark is low, the recognition of the relative position between the vehicle 1 and the lane mark based on the lane mark detection result by the lane mark position detection unit 11 is stopped.

  Hereinafter, according to the flowcharts shown in FIGS. 3 to 4, the determination of the reliability of the lane mark detection by the lane mark position recognition means 13, and the execution and stop of the relative position recognition of the vehicle 1 and the lane mark based on the determination result. Switching processing and reliability recovery determination value setting processing by the reliability recovery determination value setting means 12 will be described. The processes according to the flowcharts shown in FIGS. 3 to 4 are repeatedly executed every control cycle of the lane recognition device 10.

  In STEP 1 of FIG. 3, data indicating the lane mark detection result (with lane mark detection / without lane mark detection) by the lane mark detection unit 11 is stored in the ring buffer 14. Subsequent STEP2 to STEP5 are processes by the lane mark position recognizing means 13, and the lane mark position recognizing means 13 is the data corresponding to the last n pieces of data from the data stored in the ring buffer 14 in STEP2 according to the following equation (1). An average lane mark detection rate Rt (corresponding to the first lane mark detection rate of the present invention) in the control cycle is calculated.

  Where Rt: average lane mark detection rate in the last n control cycles, n: ring buffer size (30 in this embodiment), m: number of data stored indicating lane mark detection.

  In subsequent STEP 3, the lane mark position recognizing means 13 determines whether or not the determination of the reliability of the lane mark detection in the previous control cycle is OK. When the reliability determination in the previous control cycle is OK, the process proceeds to STEP 4 where the lane mark position recognition unit 13 determines that the lane mark detection rate Rt has a reliability decrease determination value Th2 (50% in this embodiment). It is determined whether or not it is higher.

  When the lane mark detection rate is higher than the reliability decrease determination value Th2, the process proceeds to STEP5, and the lane mark position recognizing means 13 outputs data for notifying the reliability OK to the ECU 20. The lane mark position recognizing unit 13 recognizes the relative position between the vehicle 1 and the lane mark in the real space based on the detection result of the image portion of the lane mark by the lane mark detecting unit 11, and the relative position data. Is output to the ECU 20.

  And ECU20 which received the data which notify reliability OK from the lane recognition apparatus 10, and the data of the relative position of the vehicle 1 and a lane mark performs lane maintenance control and lane departure warning control which were mentioned above.

  On the other hand, when the lane mark detection rate Rt is equal to or lower than the reliability decrease determination value Th2 in STEP 4, the process proceeds to STEP 30 in FIG. STEP 30 to STEP 32 and STEP 40 in FIG. 4 are processes by the reliability recovery determination value setting means 12.

  As shown in FIG. 5B, the reliability recovery determination value setting unit 12 determines the first half period of the ring buffer 14 (the amount of n / 2 pieces of stored data on the past side) according to the following equation (2). ) For the local lane mark detection rate Rf (corresponding to the second lane mark detection rate of the present invention), and the second half period (n / 2 on the current side) of the ring buffer 14 by the following equation (3): Local lane mark detection rate Rb (corresponding to the third lane mark detection rate of the present invention) in the stored data).

  Rf: local lane mark detection rate in the first half period of the ring buffer 14, n2: half of the ring buffer size n (30 in this embodiment), m2: first half period of the ring buffer 14 (past side) The number of stored data indicating the presence of lane mark detection in (n / 2 stored data).

  However, Rb: local lane mark detection rate in the latter half period of the ring buffer 14, n1: half of the ring buffer size n (30 in this embodiment), m1: the latter half period of the ring buffer 14 (current side) The number of stored data indicating the presence of lane mark detection in (n / 2 stored data).

  The lane mark position recognizing means 13 determines whether the lane mark detection rate Rb in the second half of the ring buffer 14 is lower than 10% and the lane mark detection rate Rf in the first half of the ring buffer 14 is higher than 90%. Judge whether or not. The difference between 90% and 10% in this determination corresponds to the predetermined level of the present invention.

  Here, when the lane mark detection rate Rb in the second half of the ring buffer 14 is lower than 10% and the lane mark detection rate Rf in the first half of the ring buffer 14 is higher than 90%, the lane mark Can be assumed to have suddenly switched from a state that is easy to detect to a state that is difficult to detect.

  In this way, the lane mark is laid down, for example, at the intersection or intersection at the intersection or interchange where the lane mark suddenly switches from the state where it is easy to detect to the state where it is difficult to detect. This is a case where a point that has not been reached is reached. In this case, it is assumed that it is a very short time to travel in a place where no lane mark is laid, and it is assumed that the vehicle quickly returns to a state where it travels in the lane where the lane mark is laid.

  Therefore, in this case, the process proceeds to STEP 31, and the reliability recovery determination value setting means 12 sets the reliability recovery determination value Th1 to 60% (corresponding to the first reliability recovery determination value of the present invention). As a result, in the determination of the reliability recovery of the lane mark detection described later, a state in which the reliability is likely to be achieved is obtained.

  Here, referring to FIG. 5A, reliability is restored when the lane mark detection unit 11 continues to be in a state where no lane mark is detected and then switches to a state in which the lane mark is detected. When the determination value Th1 is set to 80%, when the time of at least 24 control cycles (24/30 × 100 = 80%) has elapsed since switching to the state where the lane mark is detected, The lane mark detection rate Rt is equal to or higher than the reliability recovery determination value Th1.

  On the other hand, when the reliability recovery judgment value Th1 is set to 60%, after switching to the state in which the lane mark is detected, 18 control cycles at the shortest (18/30 × 100 = 60%) When the time elapses, the lane mark detection rate Rt becomes equal to or higher than the reliability recovery determination value Th1.

  Therefore, by setting the reliability recovery determination value Th1 to 60%, it can be expected that the time required for recovering the reliability of lane mark detection is shortened by the time corresponding to 6 control cycles.

In subsequent STEP 32, the lane mark position recognizing means 13 is a timer for limiting the period for setting the reliability recovery judgment value Th1 to 60% (the set time of this timer corresponds to the predetermined time of the present invention). In step 33, data for notifying the ECU 20 of reliability NG is output. In this case, the lane mark position recognizing unit 13 does not execute the process of recognizing the relative position between the vehicle 1 and the lane mark based on the detection result of the lane mark by the lane mark detecting unit 11.

  On the other hand, in STEP 30, the local lane mark detection rate Rb in the second half period of the ring buffer 14 is lower than 10%, and the local lane mark detection rate Rf in the first half period of the ring buffer 14 is higher than 90%. If the condition that the value is too high is not satisfied, the process branches to STEP40.

  Here, when the condition that the lane mark detection rate Rb in the second half period of the ring buffer 14 is lower than 10% and the lane mark detection rate Rf in the first half period of the ring buffer 14 is higher than 90% is not satisfied. It can be assumed that the difference between the lane mark detection rate Rf in the first half period of the ring buffer 14 and the lane mark detection rate Rb in the second half period is small, and that the lane mark detection rate has been lowered overall. it can.

  In this way, the lane mark detection rate may decrease as a whole when the lane mark is worn. In this case, the lane mark detection rate is low when the lane mark detection rate is low. It is assumed that it will continue until it ends and reaches the section where the lane mark is not drawn.

  Therefore, in this case, the process branches to STEP 40, and the reliability recovery determination value setting means 12 sets the reliability recovery determination value Th1 to 80% (corresponding to the second reliability recovery determination value of the present invention). As a result, in the determination of the reliability recovery of the lane mark detection described later, the process proceeds to STEP 33 in a state where it is difficult to achieve reliability OK.

  Thus, when reliability NG is output at STEP33, in the next control cycle, it branches to STEP10 at STEP3 of FIG. STEP 10 to STEP 12 and STEP 20 to STEP 22 are processes for determining whether or not the reliability of lane mark detection by the lane mark detection means 11 has been recovered.

  In step 10, the lane mark position recognizing unit 13 determines whether the average lane mark detection rate Rt based on the data stored in the ring buffer 14 immediately before calculated by the above equation (1) is higher than the reliability recovery determination value Th1. Judge whether or not. When the lane mark detection rate Rt is higher than the reliability recovery determination value Th1, the process proceeds to STEP11, and the lane mark position recognition unit 13 sets the reliability recovery determination value Th1 to 80%.

  As a result, when the reliability recovery determination value Th1 is set to 60%, the reliability recovery determination value Th1 is returned to the normal value of 80%. In subsequent STEP 12, the lane mark position recognizing unit 13 outputs data indicating the reliability OK to the ECU 20. Further, the relative position between the vehicle 1 and the lane mark in the real space is recognized based on the detection result of the lane mark image portion by the lane mark detection means 11, and data of the relative position is output to the ECU 20.

  On the other hand, if the lane mark detection rate Rt is less than or equal to the reliability recovery judgment value Th1 in STEP 10, the process branches to STEP 20, and the lane mark position recognizing means 13 starts when the timer is started in STEP 32 of FIG. , It is determined whether or not the timer is up.

  When the timer is up, the process proceeds to STEP 21. STEP 21 is a process performed by the reliability recovery determination value setting means 12, and the reliability recovery determination value setting means 12 sets the reliability recovery determination value Th1 to 80%, which is a normal value. Thereby, after the reliability recovery determination value Th1 is set to 60%, the reliability recovery determination is made when the lane mark detection rate Rt does not become higher than the reliability recovery determination value Th1 until the timer expires. The value Th1 returns to the standard value of 80%.

  Therefore, after the reliability determination value Th1 is set low (60%), the reliability recovery determination value Th1 is returned to the normal value (60% →) when the situation where the reliability of lane mark detection does not improve continues. 80%). This prevents the lane mark position recognizing means 13 from restarting the recognition process of the relative position between the vehicle 1 and the lane mark in a state where the reliability of the lane mark detection is low. The reliability of the relative position recognition can be maintained high.

  In this embodiment, as shown in FIG. 5B, the local lane mark detection rate Rf in the first half period of the ring buffer 14 and the local lane mark detection rate Rb in the second half period are used. Although the reliability recovery judgment value Th1 is set, the local detection of the lane mark is performed based on the result of the presence / absence of the lane mark detection in each control cycle in the predetermined period immediately before being stored in the ring buffer 14. The effect of the present invention can be obtained by setting the reliability recovery judgment value Th1 according to the mode of change of the rate.

  For example, the local lane mark detection rate is calculated for every three consecutive buffers of the ring buffer 14, and the reliability is restored when a mode of change in which the local lane mark detection rate rapidly decreases is detected. The determination value Th1 may be set lower than the normal value.

  In this embodiment, the time for setting the reliability recovery determination value Th1 to a value (60%) lower than the normal value (80%) is limited by the timer. The effects of the present invention can be obtained.

Explanatory drawing which showed the mounting aspect to the vehicle of the lane recognition apparatus of this invention. The block diagram of the lane recognition apparatus shown in FIG. The flowchart of the process of the reliability judgment of lane mark detection, and the switching of execution and stop of relative position recognition between the vehicle and the lane mark based on the result of the reliability judgment. 10 is a flowchart of reliability recovery determination value setting processing. Explanatory drawing of a ring buffer and a local lane mark detection rate. Explanatory drawing of the reliability judgment of a lane mark detection.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Camera, 10 ... Lane recognition device, 11 ... Lane mark detection means, 12 ... Reliability recovery judgment value setting means, 13 ... Lane mark position recognition means, 14 ... Ring buffer, 20 ... ECU

Claims (5)

Lane mark detection means for executing a process for detecting a lane mark that divides a road lane from a road image around the vehicle imaged by a camera mounted on the vehicle at predetermined intervals;
Based on the detection result of the lane mark by the lane mark detection unit, the relative position between the lane mark and the vehicle is recognized, and the average detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before is determined. When the first lane mark detection rate is equal to or lower than a predetermined reliability decrease determination value, the recognition of the relative position is stopped, and then the first lane mark detection rate is determined as the reliability decrease determination. Lane mark position recognition means for resuming the recognition of the relative position when the reliability recovery determination value is higher than the value,
When the first lane mark detection rate becomes equal to or lower than the reliability decrease determination value, according to the aspect of the change in the local detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before A lane recognition device comprising: a reliability recovery determination value setting means for setting the reliability recovery determination value. The lane recognition device according to claim 1,
When the first lane mark detection rate is equal to or lower than the reliability decrease determination value, the reliability recovery determination value setting unit is configured to perform the lane mark detection unit in the first half period of the plurality of the predetermined cycles immediately before. Whether or not the second lane mark detection rate, which is the lane mark detection rate, is higher than a predetermined level than the third lane mark detection rate, which is the lane mark detection rate by the lane mark detection means in the second half period. Judgment
When the second lane mark detection rate is higher than the third lane mark detection rate by the predetermined level or more, the reliability recovery determination value is set to a first reliability recovery determination value, and the second lane mark detection rate is When the lane mark detection rate is not higher than the predetermined level by more than the third lane mark detection rate, the reliability recovery determination value is set to a second reliability recovery determination value higher than the first reliability recovery determination value. A lane recognition device characterized by being set to: In the lane recognition device according to claim 1 or 2,
The reliability recovery determination value setting means sets the first reliability recovery determination value to the first reliability recovery determination value, and then sets the first lane mark detection rate within the predetermined time. The lane recognition device according to claim 1, wherein when the recovery determination value is not greater than or equal to the recovery determination value, the reliability recovery determination value is set to the second reliability recovery determination value. A camera,
Lane mark detection means for executing processing for detecting a lane mark that divides the lane of the road from a road image around the host vehicle captured by the camera at predetermined intervals;
Based on the detection result of the lane mark by the lane mark detection unit, the relative position between the lane mark and the host vehicle is recognized, and the average detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before is determined. When the first lane mark detection rate is equal to or lower than a predetermined reliability decrease determination value, the recognition of the relative position is stopped, and then the first lane mark detection rate is determined as the reliability decrease determination. Lane mark position recognition means for resuming the recognition of the relative position when the reliability recovery determination value is higher than the value,
When the first lane mark detection rate becomes equal to or lower than the reliability decrease determination value, according to the aspect of the change in the local detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before And a reliability recovery determination value setting means for setting the reliability recovery determination value. A computer having means for accessing data of a captured image of a camera mounted on a vehicle;
Lane mark detection means for executing processing for detecting a lane mark that divides a road lane from a road image around the vehicle imaged by the camera at predetermined intervals;
Based on the detection result of the lane mark by the lane mark detection unit, the relative position between the lane mark and the vehicle is recognized, and the average detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before is determined. When the first lane mark detection rate is equal to or lower than a predetermined reliability decrease determination value, the recognition of the relative position is stopped, and then the first lane mark detection rate is determined as the reliability decrease determination. Lane mark position recognition means for resuming the recognition of the relative position when the reliability recovery determination value is higher than the value,
When the computer detects that the first lane mark detection rate is equal to or lower than the reliability decrease determination value, a change in the local detection rate of the lane mark by the lane mark detection unit in the plurality of predetermined periods immediately before the first lane mark detection rate A lane recognition program that functions as a reliability recovery determination value setting means for setting the reliability recovery determination value according to the aspect.

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