Display control device for vehicles and road condition detection device for vehicles

Abstract

To provide a display control device for vehicles and a road condition detection device for vehicles to prevent problems with display and other controls when using a camera to obtain information.SOLUTION: A display control device 1 for a vehicle acquires information regarding a road condition while the vehicle is driving based on images or videos captured by a forward camera 301. Then, based on road map information or vehicle information regarding the vehicle's behavior, the reliability Drel of the information regarding the condition is determined, and the information regarding the condition (curvature C) is updated to the newly acquired information according to the reliability Drel.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a display control device for a vehicle and a road condition detection device for a vehicle. [Background technology]

[0002] There is a technology that generates an image showing the condition of the road ahead of the vehicle and displays the image on a display to encourage the driver to recognize the condition of the road. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-145434 A Summary of the Invention [Problem to be solved by the invention]

[0004] As systems become more sophisticated, the development of technology that displays information on road conditions in real time, in addition to landmarks such as road signs, is progressing. However, when cameras are used to obtain information, the complexity of the boundary lines that divide lanes (called "lane marks") makes it difficult to use on general roads, and currently, only consideration is being given to using such systems on expressways, where it is considered to be relatively easy. When using such systems on general roads, there is a concern that detection of road shape, particularly curvature, one of its indicators, based on images from cameras is not stable, and hunting occurs in the display, which may make drivers feel uneasy.

[0005] In view of this situation, the present invention aims to provide a vehicle display control device and a vehicle road condition detection device that can suppress problems occurring in the display and other controls when a camera is used to acquire information. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, a vehicle display control device according to one embodiment of the present invention comprises a road information acquisition means for acquiring information regarding the condition of the road on which the vehicle is traveling based on an image or video captured by a front camera positioned so as to capture the road in front of the vehicle, a reliability determination means for determining the reliability of the information regarding the condition acquired by the road information acquisition means based on map information of the road or vehicle information regarding the behavior of the vehicle, a road information update means for updating the information regarding the condition to the latest information acquired by the road information acquisition means depending on the reliability determined by the reliability determination means, and a road information display means for displaying the information updated by the road information update means.

[0007] A road condition detection device for a vehicle according to another aspect of the present invention comprises a road information acquisition means for acquiring information regarding the condition of the road on which the vehicle is traveling based on an image or video captured by a front camera positioned so as to capture the road in front of the vehicle, a reliability determination means for determining the reliability of the information regarding the condition acquired by the road information acquisition means based on map information of the road or vehicle information regarding the behavior of the vehicle, and a road information update means for updating the information regarding the condition to the latest information acquired by the road information acquisition means depending on the reliability determined by the reliability determination means. Effect of the Invention

[0008] According to one embodiment of the present invention, the reliability of information acquired from an image or video captured by a forward camera is determined, and information used for display and other controls is updated according to the reliability. This makes it possible to prevent a situation in which, when a forward camera is used to acquire information, detection becomes unstable or hunting occurs in the display, causing the driver to feel uneasy or causing problems in the display or other controls. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing a configuration of a display control device for a vehicle according to an embodiment of the present invention; [Diagram 2] 2 is a schematic diagram showing an internal configuration of a controller (display controller) according to the above embodiment. FIG. [Diagram 3] 10 is a flowchart showing an overall flow of control (curvature display control) performed by a display controller. [Figure 4] 10 is a flowchart showing the content of an update possibility determination process in the control. [Diagram 5] 4 is a flowchart showing the contents of a gain setting process in the control; [Figure 6] 11 is a schematic diagram showing an example of a curvature display image that can be switched by the above control. FIG. [Figure 7] FIG. 11 is an explanatory diagram showing an example of update availability determination using a count value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] FIG. 1 shows an overall configuration of a display control device 1 for a vehicle according to an embodiment of the present invention.

[0012] The display control device 1 according to this embodiment includes a display controller 101. The display controller 101 is configured as an electronic control unit. The display control device 1 further includes a vehicle position sensor 201, an acceleration sensor 202, and other sensors capable of acquiring information used for control by the display controller 101, as well as a direction indicator 203, a camera for monitoring the front (hereinafter referred to as a "front camera") 301, an in-vehicle navigation system 401, and an external communication unit 501.

[0013] The display controller 101 is composed of a microcomputer equipped with a central processing unit (CPU), an input / output interface, and storage devices such as ROM and RAM. The display controller 101 constitutes the calculation section of the display control device 1, and receives output signals from various sensors that constitute the detection section of the display control device 1, such as the vehicle position sensor 201. The display controller 101 then performs a predetermined calculation related to display control based on the output information of the sensors, generates a command signal according to the result, and outputs it to the display unit 601.

[0014] The vehicle position sensor 201 detects the current position of the vehicle. The vehicle position sensor 201 is equipped with a satellite positioning system (GPS) receiver, and outputs the current position of the vehicle detected via the GPS to the display controller 101. The display controller 101 can grasp the current position of the vehicle on a road map by comparing it with map information provided by an in-vehicle navigation system 401, which will be described later.

[0015] The acceleration sensor 202 detects the acceleration acting on the vehicle and outputs the detected acceleration to the display controller 101. A six-axis inertial sensor (IMU) can be used as the acceleration sensor 202, and the IMU can detect translational acceleration along three mutually orthogonal axes and angular velocities centered on each of these three axes. Based on these translational accelerations and angular velocities, the acceleration sensor 202 detects the vehicle's forward / rearward acceleration, left / right acceleration, and up / down acceleration, as well as pitching angular velocity, yawing angular velocity (hereinafter referred to as "yaw rate"), and rolling angular velocity.

[0016] The direction indicator 203 indicates the direction when the vehicle turns right, turns left, or changes course. In this embodiment, the output signal of the direction indicator 203 is an index indicating whether or not the driver intends to change lanes. The display controller 101 receives the output signal of the direction indicator 203, and determines whether or not the driver intends to change lanes based on this signal.

[0017] The front camera 301 is installed so that the front of the vehicle fits within its field of view, and is capable of photographing the road ahead of the vehicle, and if there is another vehicle traveling ahead of the vehicle, it is capable of photographing the vehicle. In addition to the road itself, the front camera 301 includes objects installed on the road, such as road markings and signs installed on the side of the road, as targets. In this embodiment, the front camera 301 is capable of analyzing the image of the road that has been photographed and identifying the shape of the road, such as the curvature and width of the road. The front camera 301 is configured as a camera module equipped with an imaging unit and a calculation unit, and can be installed inside the vehicle interior by being built into the rearview mirror at the top of the windshield, for example.

[0018] The in-vehicle navigation system 401 has pre-stored map information of roads, and also stores information related to the number of lanes on the road, information on road markings such as going straight, turning right or turning left, and information on traffic regulations such as legal speed limits or maximum speeds and one-way streets in association with the map information. The in-vehicle navigation system 401 is capable of communicating with the vehicle position sensor 201 and is equipped with a dedicated display on which it displays the current position of the vehicle together with the road map.

[0019] The external communication unit 501 acquires information related to a construction section or an accident through wireless communication with the outside. The external communication unit 501 includes a receiver for a road traffic information and communication system (VICS (registered trademark)), and outputs road traffic information acquired through VICS (registered trademark), specifically, position information related to a construction section or an accident site, to the display controller 101. The external communication unit is not limited to this, and may acquire information related to a construction section or the like through road-to-vehicle communication.

[0020] The display unit 601 displays to the driver information about the road on which the vehicle is currently traveling, specifically, the condition of the road extending ahead of the vehicle. In this embodiment, the information displayed by the display unit 601 includes the curvature of the road or information related thereto, and the display unit 601 receives a signal indicating the curvature of the road as a command signal from the display controller 101.

[0021] The display unit 601 can be realized by a meter display, a head-up display (HUD), or any other suitable type of display unit. For example, in the case of a meter display, it can be realized by incorporating a screen for displaying road conditions into the meter display behind the handle (i.e., the steering wheel), and in the case of a head-up display, it can be realized by forming an area for displaying road conditions in the projection area of ​​the windshield.

[0022] The display controller 101 is connected to the forward camera 301, the in-vehicle navigation system 401, and the external communication unit 501 via an in-vehicle network based on the CAN protocol or the like so as to be able to communicate with each other.

[0023] FIG. 6 is a schematic diagram showing an example of an image (in this embodiment, a curvature display image IMG) displayed by the display unit 601. As shown in FIG.

[0024] In this embodiment, an image IMG showing the curvature of the road (hereinafter referred to as a "curvature display image") is displayed as information on the road condition, and is switched depending on the magnitude of the curvature. FIG. 6 shows, as an example, a curvature display image IMG that is displayed when the vehicle V is traveling on a road R that curves to the left ahead of the vehicle (i.e., a left curved road). FIG. 6(a) shows a curvature display image IMG1 when the vehicle V is traveling on a left curved road R1 with the smallest curvature, in other words, the largest curve radius, and FIG. 6(c) shows a curvature display image IMG3 when the vehicle V is traveling on a left curved road R3 with the largest curvature, in other words, the smallest curve radius. FIG. 6(b) shows a curvature display image IMG2 when the vehicle V is traveling on a left curved road R2 with a curvature magnitude between the above.

[0025] In this embodiment, the curvature display images IMG (IMG1, IMG2, IMG3) express the curvature of the road R by the degree of curvature of the left and right lane marks LN1, LN2 indicating the road R or the boundary line of the lane. Specifically, in the curvature display image IMG1 of FIG. 6(a) which has the smallest curvature, the lane marks LN1, LN2 are displayed as extending straight ahead of the vehicle V. In contrast, in the curvature display image IMG3 of FIG. 6(c) which has the largest curvature, the lane marks LN1, LN2 are displayed as curving significantly to the left. Here, the direction in which the lane marks LN1, LN2 curve matches the curvature direction of the road R. In this embodiment, in addition to the road R and the lane marks LN1, LN2, an arrow A (A1, A2) pointing in the curvature direction of the road R is also displayed. The curvature display images IMG2 and IMG3 indicate that the curve direction of the road R is leftward with left-facing arrows A1 and A2, and indicate the degree of the curve, i.e., the magnitude of the curvature, with the lengths of the arrows A1 and A2. Specifically, the arrow A2 of the curvature display image IMG3 shown in Fig. 6(c) is longer than the arrow A1 of the curvature display image IMG2 shown in Fig. 6(b), indicating that the curvature indicated by the curvature display image IMG3 is greater than the curvature indicated by the curvature display image IMG2.

[0026] In this way, Fig. 6 shows the curvature of the left curve road R by switching between three curvature display images IMG1, IMG2, and IMG3 according to the magnitude of the curvature, including 0. However, there is no limit to the number of stages for switching the curvature display images IMG, and an appropriate number other than 3 may be used. For example, it is possible to display the curvature of the left curve road R by switching between six images, including the case where the curvature is 0.

[0027] FIG. 2 shows a schematic diagram of the internal configuration of the display controller 101 according to this embodiment.

[0028] In this embodiment, the display controller 101 includes, as basic elements, a map information acquisition unit B101, a vehicle information acquisition unit B102, a road information acquisition unit B103, a reliability determination unit B104, a road information update unit B105, and an information display control unit B106. The functions of these units are realized in software by a central processing unit included in the display controller 101 reading a control program stored in a storage device and performing calculations in accordance with the program.

[0029] The map information acquisition unit B101 acquires the current position of the vehicle from the vehicle position sensor 201, as well as road map information from the in-vehicle navigation system 401 and information on construction zones or accidents from the external communication unit 501. As described above, the information acquired by the display controller 101 from the in-vehicle navigation system 401 includes, in addition to road map information, information on the number of lanes on the road being traveled, information on road markings such as going straight, turning right or turning left, and information on traffic laws. The information acquired by the display controller 101 from the external communication unit 501 includes position information on the construction zone or the site of the accident.

[0030] The vehicle information acquisition unit B102 acquires the yaw rate YAW of the vehicle from the acceleration sensor 202 as information relating to the behavior of the vehicle, and receives the output signal of the direction indicator 203.

[0031] The road information acquisition unit B103 acquires the road curvature C as information relating to the road conditions from the front camera 301. The road information acquisition unit B103 constitutes the "road information acquisition means" according to this embodiment.

[0032] The reliability determination unit B104 determines the reliability of the information on the situation acquired by the road information acquisition unit B103 (hereinafter referred to as "acquired information") based on the map information acquired from the map information acquisition unit B101 and the vehicle information acquired from the vehicle information acquisition unit B102. In this embodiment, the reliability of the curvature C acquired by the road information acquisition unit B103 is determined, and this determination is based on the type of road on which the vehicle is traveling, the presence or absence of a branch road ahead of the vehicle, an increase or decrease in the number of lanes ahead of the vehicle, the presence or absence of a construction zone ahead of the vehicle, the yaw rate YAW of the vehicle, and the presence or absence of the driver's intention to change lanes.

[0033] As a general tendency, if the road on which the vehicle is traveling is an expressway, the reliability can be determined to be high, and if the road is a general road, the reliability can be determined to be low. If there is a fork in the road ahead of the vehicle, the reliability can be determined to be low, and if there is no fork, the reliability can be determined to be high. If there is an increase or decrease in the number of lanes ahead of the vehicle, the reliability can be determined to be low, and if there is no increase or decrease in the number of lanes and the number of lanes is constant, the reliability can be determined to be high. If there is no construction zone ahead of the vehicle, the reliability can be determined to be high, and if there is a construction zone, the reliability can be determined to be low. Furthermore, if the driver has no intention of changing lanes, the reliability can be determined to be high, and if there is an intention of changing lanes, the reliability can be determined to be low. The yaw rate YAW of the vehicle can be converted into the curvature of the trajectory followed by the vehicle and compared with the curvature of the road acquired from the front camera 301, and can be used as an index of reliability. Based on the degree of agreement or discrepancy between the two curvatures, if the discrepancy is large, the reliability is determined to be low, and if the discrepancy is small, the reliability is determined to be high.

[0034] The map information acquisition unit B101, the vehicle information acquisition unit B102, and the reliability determination unit B104 constitute a "reliability determination means" according to this embodiment.

[0035] The road information update unit B105 updates the information recognized by the display controller 101 as information relating to road conditions to the latest information acquired by the road information acquisition unit B103, depending on the reliability determined by the reliability determination unit B104. In other words, the update conditions for the acquired information are switched depending on this reliability. If the reliability of the acquired information is high, the update conditions are strengthened and updates are performed more frequently. In contrast, if the reliability of the acquired information is low, the update conditions are relaxed and updates are performed less frequently. The road information update unit B105 constitutes the "road information update means" according to this embodiment.

[0036] The information display control unit B106 generates a command signal indicating the information after the update by the road information update unit B105, and outputs this to the display unit 601. The display unit 601 generates or selects and displays the updated information, that is, an image (curvature display image) IMG according to the curvature. The information display control unit B106 constitutes the "road information display means" according to this embodiment.

[0037] Fig. 3 is a flowchart showing the overall flow of control (hereinafter referred to as "curvature display control") performed by the display controller 101. Fig. 4 shows the contents of update possibility determination processing in the curvature display control, and Fig. 5 shows the contents of gain setting processing in the curvature display control. The display controller 101 executes the curvature display control at a predetermined cycle after power is turned on by operating the start switch.

[0038] 3, in S101, the curvature C of the road is detected. In this embodiment, the curvature C is detected by acquiring the curvature C from the front camera 301 as information on the road condition, and the curvature C newly acquired in the current control is hereinafter referred to as the "acquired curvature."

[0039] In S102, it is determined whether the curvature of the road, that is, the acquired curvature C, has changed from the current curvature (hereinafter referred to as the "set curvature") Cset recognized by the display controller 101. In this embodiment, the range of the curvature C is divided into three ranges according to its magnitude, specifically, a minimum first range including the case where the curvature C is 0, an intermediate second range larger than the first range, and a maximum third range even larger than the second range. Then, it is determined whether the acquired curvature C has transitioned to a range different from the current range. If the acquired curvature C is different from the set curvature Cset, in other words, if the acquired curvature C has deviated from the current range to which the set curvature Cset belongs and transitioned to a range different from the current range, the process proceeds to S103, and if the acquired curvature C maintains the current range, the process proceeds to S107.

[0040] In S103, a determination is made as to whether or not the acquired curvature C can be updated. This determination is made according to the procedure shown in the flowchart of FIG.

[0041] In S104, if the reliability of the acquired curvature C is high and the update is possible as a result of the update possibility determination, the process proceeds to S105, and if the reliability of the acquired curvature C is low and the update is not possible, the process proceeds to S107.

[0042] In S105, the set curvature Cset is updated to the acquired curvature C. As a result, the display controller 101 recognizes the curvature C newly acquired in the current control as the curvature of the road.

[0043] In S106, the display of the curvature by the display unit 601, that is, the curvature display image IMG is changed. The display controller 101 instructs the display unit 601 to display the curvature display image IMG1 shown in Fig. 6(a) when the acquired curvature C belongs to the first range, instructs the display unit 601 to display the curvature display image IMG2 shown in Fig. 6(b) when the acquired curvature C belongs to the second range, and instructs the display unit 601 to display the curvature display image IMG3 shown in Fig. 6(c) when the acquired curvature C belongs to the third range.

[0044] In S107, the current curvature display image IMG is maintained, and the display of the curvature by the display unit 601 is maintained.

[0045] 4, in S201, the gain G is set. The gain G is set in accordance with the procedure shown in the flowchart of FIG.

[0046] In S202, an increment value N of the count value CNT for each control cycle is calculated. The increment value N is calculated by multiplying a base value N0 by a gain G (N=N0×G). The base value N can be set appropriately, but is set to 1 in this embodiment (i.e., N=G). In the update feasibility determination process according to this embodiment, a count value CNT for determination is set, and an increment value N is set as the change in the count value CNT. Then, the count value CNT is compared with a predetermined threshold value CNT1, and if the count value CNT has increased to this threshold value CNT1 by adding the increment value N, it is determined that the curvature can be updated. The count value CNT corresponds to an "update determination value" according to this embodiment.

[0047] In S203, the count value CNT is updated by adding the increment value N to the current count value CNT (CNT=CNT+N).

[0048] In S204, it is determined whether the updated count value CNT is equal to or greater than the threshold value CNT1. If the count value CNT is equal to or greater than the threshold value CNT1, the process proceeds to S206, and if it is less than the threshold value CNT1, the process proceeds to S205.

[0049] In S205, it is determined whether or not a change has occurred in the curvature of the road, in other words, whether or not a change has occurred in the curvature C detected by the front camera 301. If no change has occurred in the curvature C and the curvature C is constant, the process returns to S201 and continues the update possibility determination process, whereas if a change has occurred in the curvature C, it is determined that a change has occurred in the curvature C (i.e., the acquired curvature) that is the subject of the update possibility determination, that is, the subject of the reliability determination, and the process proceeds to S207 to stop the update possibility determination.

[0050] In S206, it is determined that the update is possible.

[0051] In S207, it is determined that the update is not possible.

[0052] In the flowchart shown in FIG. 5, at S301, external information is acquired. The external information includes the type of the road on which the vehicle is traveling, the presence or absence of a branch road ahead of the vehicle, the increase or decrease in the number of lanes ahead of the vehicle, the presence or absence of a construction section ahead of the vehicle, the vehicle's yaw rate YAW, and the presence or absence of the driver's intention to change lanes.

[0053] At S302, based on the external information acquired at S301, the reliability of the curvature C acquired from the front camera 301 is determined, and an evaluation value Drel serving as an index is calculated. Then, at S303 to S306, a distribution according to the evaluation value Drel is performed, and at S307 to S311, a gain G according to the evaluation value Drel is set. In the present embodiment, the reliability is divided into five levels with D1, D2, D3, and D4 as boundary values. Specifically, in descending order of reliability, they are reliability 1 (D1 ≤ Drel), reliability 2 (D2 ≤ Drel < D1), reliability 3 (D3 ≤ Drel < D2), reliability 4 (D4 ≤ Drel < D3), and reliability 5 (Drel < D4). Reliability 1 is the highest reliability, and reliability 5 is the lowest reliability.

[0054] In the determination of the reliability, when the type of the road on which the vehicle is traveling is a highway and the deviation of the curvature C acquired from the front camera 301 with respect to the curvature (hereinafter referred to as "converted curvature") Ccnv converted from the yaw rate YAW is less than a predetermined value (that is, when the deviation of the acquired curvature C with respect to the converted curvature Ccnv is small), the reliability of the curvature C is determined as the highest reliability 1.

[0055] On the contrary, when the deviation of the acquired curvature C with respect to the converted curvature Ccnv is equal to or greater than the predetermined value and the deviation is large, the evaluation criterion is switched depending on whether the type of the road is a highway or an ordinary road.

[0056] When the deviation of the acquired curvature C with respect to the converted curvature Ccnv is large and the type of the road is a highway, the following criteria are used.

[0057] The acquired curvature C is compared with the curvature of the clothoid curve. When the degree of sign agreement between the two is less than a predetermined value, it is determined as the lowest confidence level 4 among confidence levels 2 to 4. The clothoid curve is a curve adopted for the curved section of a highway, particularly for the connection section between a straight section and a curved section. In the present embodiment, the display controller 101 stores in advance the curvature of the clothoid curve in association with map information.

[0058] When the degree of sign agreement between the acquired curvature C and the curvature of the clothoid curve is equal to or greater than a predetermined value and any of the following conditions a) to d) is satisfied, it is determined as the intermediate confidence level 3 among confidence levels 2 to 4. a) There is a branch road ahead of the vehicle. b) There is an increase or decrease in the number of lanes ahead of the vehicle. c) There is a construction section ahead of the vehicle. d) The driver intends to change lanes.

[0059] When the degree of sign agreement between the acquired curvature C and the curvature of the clothoid curve is equal to or greater than a certain value and none of the above conditions a) to d) is satisfied, it is evaluated as the highest confidence level 2 among confidence levels 2 to 4.

[0060] And when the deviation of the acquired curvature C from the converted curvature Ccnv is large and the road type is a general road, the confidence level of the curvature C is determined as the lowest confidence level 5.

[0061] In S307, assuming that the confidence level of the curvature C is the highest (confidence level 1), the gain G is set to the largest value G1.

[0062] In S308, assuming that the confidence level of the curvature C is relatively high (confidence level 2), the gain G is set to a value G2 (<G1) smaller than that in the case of confidence level 1.

[0063] In S309, assuming that the confidence level of the curvature C is intermediate (confidence level 3), the gain G is set to a value G3 (<G2) smaller than that in the case of confidence level 2.

[0064] In S310, assuming that the reliability of the curvature C is relatively low (reliability 4), the gain G is set to a value G4 (<G3) smaller than that in the case of reliability 3.

[0065] In S311, assuming that the reliability of the curvature C is the lowest (reliability 5), the gain G is set to the smallest value G5 (<G4).

[0066] FIG. 7 is an explanatory diagram showing an example of update permission determination using the count value CNT.

[0067] In the present embodiment, count values CNT (CNTa, CNTb, CNTc) are set for each of the curvature display images IMG1, IMG2, IMG3, and by comparing each count value CNT with the threshold value CNT1, it is determined whether the curvature C can be updated and whether the curvature display image IMG can be switched.

[0068] Here, assume a case where the curvature C decreases and then increases from the state where the display unit 601 is displaying the curvature display image IMG2 shown in FIG. 6(b). Due to the decrease in the curvature C acquired from the front camera 301 (at time t1), the count value CNT (that is, the second count value CNTb for medium curvature) is reset to 0, and the reliability of the decreased curvature C is determined. An increment value N (=N0×G) corresponding to the reliability is sequentially added to the count value CNT (that is, the first count value CNTa for small curvature). When the first count value CNTa increases to the threshold value CNT1 (at time t2), it is determined that an update is possible, the set curvature Cset is updated with the acquired curvature C, and the curvature display image IMG is changed to the first image IMG1 for small curvature shown in FIG. 6(a).

[0069] Thereafter, when the acquired curvature C from the front camera 301 increases (time t3), the first count value CNTa is reset to 0, the reliability of the increased curvature C is determined, and an increment value N (=N0×G) according to the reliability is sequentially added to the second count value CNTb. When the second count value CNTb increases to the threshold value CNT1 (time t4), it is determined that updating is possible, the set curvature Cset is updated with the acquired curvature C, and the curvature display image IMG is changed to the second image IMG2 for medium curvature shown in FIG. 6(b).

[0070] Similarly, when the acquired curvature C from the front camera 301 further increases (time t5), the second count value CNTb is reset to 0, the reliability of the increased curvature C is determined, and an increment value N (=N0×G) according to the reliability is sequentially added to the third count value CNTc for large curvatures. When the third count value CNTc increases to the threshold value CNT1 (time t6), it is determined that updating is possible, the set curvature Cset is updated with the acquired curvature C, and the curvature display image IMG is changed to the third image IMG3 for large curvatures shown in FIG. 6(c).

[0071] The display control device 1 for a vehicle according to this embodiment has the above-mentioned configuration. The effects obtained by this embodiment will be described below.

[0072] The reliability of information on road conditions obtained from an image or video captured by the forward camera 301 is determined, and information used for display and other controls is updated according to this reliability. This makes it possible to prevent a situation in which detection is unstable or hunting occurs in the display when the forward camera 301 is used to obtain information, causing problems in the display or other controls. For example, it is possible to avoid a situation in which hunting occurs in the display, causing the driver to feel uneasy.

[0073] By displaying information that has been updated according to the reliability, it is possible to encourage the driver to be aware of the conditions of the road on which he or she is traveling, without making the driver feel uneasy.

[0074] For example, by displaying the curvature of the road on which the vehicle is traveling while driving autonomously, the driver can confirm that the vehicle's driving conditions (e.g., steering) are in line with the shape of the road, providing a sense of security.

[0075] Here, the higher the reliability of the information obtained from the forward camera 301, for example, the curvature C, the more frequently the information is updated to the latest information, making it possible to display information that matches the actual road conditions as closely as possible.

[0076] Furthermore, a count value CNT that can be increased or decreased is set, and whether or not updating is possible is determined based on this count value CNT, and the amount of change (increment value N in this embodiment) added to or subtracted from the count value CNT is made different depending on the reliability of the information. For example, by switching the gain G, the increment value N is increased as the reliability increases, and the increment value N is decreased as the reliability decreases. This makes it possible to uniformly evaluate information acquired from the front camera 301 with different reliability, and simplifies control.

[0077] The count value CNT is not limited to being increased by different increment values ​​N, but the change may have a positive or negative value depending on the reliability, and when the reliability is high, the count value CNT may be increased by a positive change, and when the reliability is low, the count value CNT may be decreased by a negative change.

[0078] In this embodiment, the display control device 1 is configured for the purpose of displaying information itself, and after the power is turned on by the vehicle start switch, the display control device 1 is always activated, so that the driver can always recognize the road curvature and its changes through the curvature display image IMG while driving the vehicle. The display control device 1 is not limited to this, and can also be configured to be provided with an activation switch so that the driver can select between activation and stop by operating the activation switch.

[0079] Furthermore, the display control device 1 may be configured to operate as a part of another device or in cooperation with another device to display information. For example, the display control device 1 displays information as a part of a driving assistance device of a vehicle that performs automatic cruise control or in cooperation with the same. By performing automatic cruise control, the steering angle of the vehicle is automatically controlled so that the vehicle maintains the lane in which it is traveling or follows another vehicle ahead. The display control device 1 displays information such as curvature acquired from the forward camera 301 and updated according to the reliability on the display unit 601, and provides the information to the driving assistance device. The driving assistance device refers to the provided information and reflects it in the automatic cruise control. [Explanation of symbols]

[0080] V...vehicle, display control device...1, 101...display controller, 201...vehicle position sensor, 202...acceleration sensor, 203...direction indicator, 301...forward camera, 401...in-vehicle navigation system, 501...external communication unit, 601...display unit.

Claims

1. a road information acquisition means for acquiring information regarding the condition of the road on which the vehicle is traveling based on an image or video captured by a front camera disposed so as to be able to capture an image of the road ahead of the vehicle; a reliability determination means for determining reliability of the information on the situation acquired by the road information acquisition means based on map information on the road or vehicle information on the behavior of the vehicle; a road information update means for updating the information regarding the situation to the latest information acquired by the road information acquisition means in accordance with the reliability determined by the reliability determination means; and a road information display means for displaying information updated by the road information update means.

2. The display control device for a vehicle according to claim 1 , wherein the road information acquisition means acquires a curvature of the road as the information relating to the situation.

3. 3. The display control device for a vehicle according to claim 1, wherein the road information update means updates the information more frequently as the reliability of the information relating to the situation becomes higher.

4. 4. The vehicle display control device according to claim 3, wherein the road information update means has an update determination value that is set to be increaseable or decreaseable, and updates the information when the update determination value reaches a predetermined value, and the amount of change that is added to or subtracted from the update determination value at each predetermined time is made different depending on the reliability of the information.

5. 4. The display control device for a vehicle according to claim 3, wherein the map information includes at least one of the following: a type of road on which the vehicle is traveling, the presence or absence of a branching road ahead of the vehicle, an increase or decrease in the number of lanes ahead of the vehicle, and the presence or absence of a construction zone ahead of the vehicle.

6. The display control device for a vehicle according to claim 3 , wherein the vehicle information includes at least one of a yaw rate of the vehicle and whether or not the driver has an intention to change lanes.

7. a road information acquisition means for acquiring information regarding the condition of the road on which the vehicle is traveling based on an image or video captured by a front camera disposed so as to be able to capture an image of the road ahead of the vehicle; a reliability determination means for determining reliability of the information on the situation acquired by the road information acquisition means based on map information on the road or vehicle information on the behavior of the vehicle; a road information update means for updating the information relating to the situation to the latest information acquired by the road information acquisition means in accordance with the reliability determined by the reliability determination means.

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