Driving assistance device and driving assistance method

Abstract

To provide a driver assistance device and driver assistance method that can reduce the stress that the proposed solution causes to the driver. [Solution] The acquisition unit 11 of the driving assistance device 10 of this disclosure acquires map information and the location information of the vehicle. If the determination unit 12 determines that the road on which the vehicle is traveling is a road with multiple lanes based on the information acquired, the image acquisition unit 13 acquires image information of the area around the vehicle, and the speed acquisition unit 14 acquires the speed of the vehicle. The measurement unit 15 measures, based on the image information of the area around the vehicle, the difference in the number of other vehicles that have overtaken the vehicle (first number) and the number of other vehicles that have been overtaken by the vehicle (second number) at predetermined time intervals for each of the multiple lanes. The suggestion unit 16 suggests a recommended lane to the driver of the vehicle, determined from among the multiple lanes based on the difference in the number of vehicles. Here, the measurement unit 15 changes the predetermined time interval according to the speed of the vehicle.

Description

Technical Field

[0001] The present invention relates to a driving support device and a driving support method.

Background Art

[0002] During traffic jams, lane changes were made based on the driver's and passengers' visual observations and intuition. Therefore, when changing lanes, there was a problem that the driver was under great stress due to the burden on the driver who visually confirmed, differences in opinions with passengers, and the lane change turning out to be in the wrong direction.

[0003] In Patent Document 1, based on the comparison between a set vehicle speed preset to keep the host vehicle running at a constant speed, the driving situation of a preceding vehicle that travels ahead of the host vehicle in the driving lane where the host vehicle travels, and the driving situation of an adjacent vehicle that travels ahead of the host vehicle in an adjacent lane adjacent to the driving lane, a recommended driving lane for the host vehicle to travel is determined, and a driving support technique for automatically making a proposal based on the recommended driving lane is disclosed.

[0004] In Patent Document 2, a driving support technique is disclosed in which the number of vehicles traveling in a target lane that the observation vehicle has overtaken or passed by is counted to estimate the congestion-related state in the target lane.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Suggestions such as recommended lanes to drivers can cause stress to them. Patent documents 1 and 2 had the problem that the number of suggestions to drivers could be too high, potentially causing significant stress to the drivers.

[0007] This disclosure aims to provide a driver assistance device and driver assistance method that can reduce the stress that the proposed device imposes on the driver, taking into consideration such challenges. [Means for solving the problem]

[0008] The driver assistance device of this disclosure is An acquisition unit that acquires map information including location information for each road and information on the number of lanes provided on each road, and location information of the vehicle itself. A determination unit that determines whether the road on which the vehicle is traveling is a road with multiple lanes, based on the map information and the location information of the vehicle, If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, an image acquisition unit acquires image information of the area around the vehicle. If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, the speed acquisition unit acquires the speed of the vehicle, A measuring unit measures, based on image information captured of the area around the vehicle, the difference between the number of other vehicles that overtook the vehicle (number 1) and the number of other vehicles that were overtaken by the vehicle (number 2) at predetermined time intervals for each of the multiple lanes on the road the vehicle is traveling on. Based on the difference in the number of vehicles, the system determines a recommended lane from among multiple lanes on the road on which the vehicle is traveling, and proposes the determined recommended lane to the driver of the vehicle. The aforementioned measuring unit is The predetermined time interval is changed according to the speed of the vehicle.

[0009] The driver assistance method disclosed herein is: Computers Map information including location information for each road and information on the number of lanes provided on each road, and location information of the vehicle itself are acquired. Based on the map information and the location information of the vehicle, it is determined whether the road on which the vehicle is traveling is a road with multiple lanes. If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, then image information of the area around the vehicle is acquired. If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, the speed of the vehicle is obtained. Based on image information captured around the vehicle, for each of the multiple lanes on the road the vehicle is traveling on, the difference between the number of other vehicles that have overtaken the vehicle (number 1) and the number of other vehicles that have been overtaken by the vehicle (number 2) is measured at predetermined time intervals that are changed according to the speed of the vehicle. Based on the aforementioned difference in the number of vehicles, a recommended lane is determined from among the multiple lanes provided on the road on which the vehicle is traveling, and the determined recommended lane is proposed to the driver of the vehicle. [Effects of the Invention]

[0010] This disclosure makes it possible to provide a driver assistance device and driver assistance method that can reduce the stress that the proposed device imposes on the driver. [Brief explanation of the drawing]

[0011] [Figure 1] This is a block diagram showing an example of the configuration of a driver assistance system according to the first embodiment. [Figure 2] This flowchart shows an example of the operation of the driver assistance system according to the first embodiment. [Figure 3] This figure shows an example of the output screen of an output device that includes recommended lanes suggested to the driver of the vehicle by the suggestion unit of the driver assistance system according to the first embodiment. [Figure 4]FIG. 0 is a diagram showing an example of an output screen including a recommended lane proposed to a driver of a host vehicle by a proposal unit of a driving support system according to the first embodiment. [Figure 5] FIG. 3 is a flowchart showing an example of the operation of the driving support system according to the second embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of the operation of the driving support system according to the second embodiment. MODE FOR CARRYING OUT THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted as necessary for clarity of explanation.

[0013] As used herein, the term "road" refers to a passage provided for people and vehicles to pass through, and at least one lane is provided on the road. The term "lane" refers to a strip provided on the road so that vehicles can pass safely and smoothly. There are several types of lanes. For example, the types of lanes include a running lane, an overtaking lane, an acceleration lane, and a deceleration lane. A running lane is a lane used for normal driving. An overtaking lane is a lane used for overtaking other vehicles. An acceleration lane is a lane used for a vehicle to accelerate at a highway merge point or the like. A deceleration lane is a lane used for a vehicle to decelerate at a highway exit or the like. At intersections, lanes for proceeding in a specific direction, such as a right-turn lane or a left-turn lane, are also provided on the road. The term "host vehicle" refers to a vehicle to be subjected to driving support by the driving support systems 1 and 2 of the present disclosure. The term "other vehicle" refers to a vehicle different from the "host vehicle".

[0014] (First Embodiment) First, the configuration of the driving support system 1 according to the first embodiment will be described with reference to FIG. 1. FIG. 1 is a block diagram showing an example of the configuration of the driving support system 1 according to the first embodiment.

[0015] As shown in FIG. 1, the driving support system 1 includes a driving support device 10, a car navigation device 20, a camera 30, a speed sensor 40, an input device 50, and an output device 60. Hereinafter, the driving support device 10, the car navigation device 20, the camera 30, the speed sensor 40, the input device 50, and the output device 60 are collectively referred to as components of the driving support system 1.

[0016] The driver assistance device 10 is a computer. Specifically, the driver assistance device 10 is configured as a computer comprising a processor and memory. The processor may be, for example, a microprocessor, an MPU (Micro Processing Unit), or a CPU (Central Processing Unit). The processor may include multiple processors. The memory consists of a combination of volatile memory and non-volatile memory. The memory may include storage located separately from the processor. In this case, the processor may access the memory via an I / O interface not shown. The processor executes one or more programs that include a set of instructions for causing the computer to perform the algorithms described with reference to the drawings. The programs include a set of instructions (or software code) for causing the computer to perform one or more functions described in the embodiments when loaded into the computer. The programs may be stored in a non-temporary computer-readable medium or a tangible storage medium. Examples, but not limited to, include computer-readable media or physical storage media such as random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drives (SSDs) or other memory technologies, CD-ROMs, digital versatile discs (DVDs), Blu-ray® discs or other optical disc storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices. Programs may be transmitted over temporary computer-readable media or communication media. Examples, but not limited to, include temporary computer-readable media or communication media such as electrical, optical, acoustic or other forms of propagating signals.

[0017] The driver assistance device 10 is implemented, for example, as a server. However, the driver assistance device 10 is not limited to a server and may be implemented, for example, as equipment installed in a vehicle. The driver assistance device 10 also communicates with the car navigation system 20, camera 30, speed sensor 40, input device 50, and output device 60. The communication method is wireless or wired.

[0018] The car navigation system 20 is a computer. The car navigation system 20 can be implemented as, for example, a server. However, the car navigation system 20 is not limited to a server and may be implemented as, for example, a device installed in a vehicle. The car navigation system 20 stores map information, the vehicle's location information, and the vehicle's route information. The map information includes location information for each road. The map information also includes information on the number of lanes on each road. The location information is, for example, GNSS (Global Navigation Satellite System) information. The route information is information that shows the route from the current location to the destination.

[0019] Camera 30 is, for example, a visible light camera, an infrared camera, or a LiDAR. Camera 30 is, for example, placed in the vehicle. Camera 30 may also be a camera such as a drive recorder that is already installed in the vehicle. Camera 30 captures images of the area around the vehicle and transmits the captured image information of the area around the vehicle to the driver assistance device 10.

[0020] The speed sensor 40 is, for example, a magnetic speed sensor, an optical speed sensor, or an acceleration sensor. The speed sensor 40 is installed in the vehicle. The speed sensor 40 may also be a speed sensor that is pre-installed in the vehicle. The speed sensor 40 measures the speed of the vehicle and transmits the measured speed information of the vehicle to the driver assistance device 10.

[0021] The input device 50 is, for example, a touch panel. The input device 50 is installed in the vehicle. The input device 50 receives input from the driver of the vehicle and transmits the input information to the driver assistance device 10.

[0022] The output device 60 is, for example, a display or a speaker. The output device 60 is located in the vehicle. The output device 60 receives information from the driver assistance system 10 and outputs the received information to the driver of the vehicle.

[0023] The driving support device 10 includes an acquisition unit 11, a determination unit 12, an image acquisition unit 13, a speed acquisition unit 14, a measurement unit 15, and a suggestion unit 16.

[0024] The acquisition unit 11 acquires map information from the car navigation system 20. The acquisition unit 11 also acquires the location information of its own vehicle from the car navigation system 20.

[0025] The determination unit 12 determines, based on map information and the vehicle's location information, whether the road the vehicle is traveling on has multiple lanes. Here, a road with multiple lanes means a road with multiple lanes on one side (one direction). The determination unit 12 also determines which of the multiple lanes on the road the vehicle is traveling on is using.

[0026] If the image acquisition unit 13 determines that the road on which the vehicle is traveling has multiple lanes, it acquires image information of the vehicle's surroundings from the camera 30. In the same case, the speed acquisition unit 14 acquires the vehicle's speed information from the speed sensor 40.

[0027] Furthermore, the acquisition unit 11, determination unit 12, image acquisition unit 13, and speed acquisition unit 14 of the driving support device 10 may also have the following additional functions. The acquisition unit 11 acquires route information for the vehicle from the car navigation system 20. Alternatively, the acquisition unit 11 may acquire location information for the vehicle's destination from the car navigation system 20 instead of route information for the vehicle. In that case, the acquisition unit 11 may generate route information for the vehicle based on the map information, the vehicle's location information, and the location information for the vehicle's destination.

[0028] Furthermore, the determination unit 12 determines, based on map information, the vehicle's location information, and the vehicle's route information, whether the distance from the vehicle's current location to the junction where the vehicle plans to turn right or left is greater than or equal to a predetermined distance. The predetermined distance refers to the distance required for the vehicle to turn right or left. The junction where the vehicle plans to turn right or left may include, for example, the exit of the highway or the entrance to a service area that the vehicle is heading towards while traveling on a highway.

[0029] The image acquisition unit 13 acquires image information of the vehicle's surroundings from the camera 30 if it determines that the road the vehicle is traveling on is a road with multiple lanes, and that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance. In the same case, the speed acquisition unit 14 acquires the vehicle's speed information from the speed sensor 40. It should be noted that the image acquisition unit 13 and the speed acquisition unit 14 may acquire information not only when it is determined that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance, but also when the vehicle is outside the area from which it can return from the turning road, or when the vehicle is not in a lane change prohibited area.

[0030] The measurement unit 15 measures the difference between the number of other vehicles that have overtaken the vehicle (the first number) and the number of other vehicles that have been overtaken by the vehicle (the second number) for each of the multiple lanes on the road the vehicle is traveling on, at predetermined time intervals T, based on image information of the vehicle's surroundings. The measurement unit 15 also sets the predetermined time interval T based on the vehicle's speed information. For example, if the vehicle's speed is the first speed, the measurement unit 15 sets the time interval T to the first time interval T1 (e.g., 1 minute). On the other hand, if the vehicle's speed is the second speed, which is faster than the first speed, the measurement unit 15 sets the time interval T to a longer time interval T2 (e.g., 5 minutes) than the first time interval T1. This is because the faster the vehicle's speed, the better the flow of traffic in the lane the vehicle is traveling in can be judged. When the lane flow is good, the time interval T is set to be longer to reduce the number of measurements of the first and second numbers and the number of recommended lane suggestions (described later) associated with the measurements. Reducing the number of times the system suggests a recommended lane can reduce stress on the driver of the vehicle.

[0031] The measurement unit 15 may also measure the difference in the number of vehicles between the first and second vehicles at a predetermined time interval T for each of the multiple lanes on the road on which the vehicle is traveling that the vehicle is not traveling in, at least one lane in which the vehicle is not traveling.

[0032] The suggestion unit 16 determines a recommended lane from among the multiple lanes on the road on which the vehicle is traveling, based on the measured difference in the number of vehicles between the first and second vehicles. Specifically, the suggestion unit 16 determines a lane as a recommended lane if the difference in the number of vehicles between the first and second vehicles (where the first vehicle > the second vehicle) is greater than or equal to a predetermined vehicle threshold A, that is, a lane where the flow of traffic is judged to be good. Here, the vehicle threshold A indicates the number of vehicles required for the target lane to be judged to have a good flow of traffic. Here, the recommended lane may be one lane or multiple lanes. The suggestion unit 16 then proposes the determined recommended lane to the driver of the vehicle via the output device 60. If there are multiple determined recommended lanes, the suggestion unit 16 may prioritize the multiple recommended lanes and propose them to the driver of the vehicle via the output device 60.

[0033] Next, the operation of the driver assistance system 1 according to the first embodiment will be explained using Figures 2, 3, and 4.

[0034] Figure 2 is a flowchart showing an example of the operation of the driver assistance system 1 according to the first embodiment. As shown in Figure 2, the driver assistance system 1 starts the following series of processes upon receiving a start command from the vehicle's driver via the input device 50. The driver assistance system 1 also repeats the following series of processes at predetermined intervals. Furthermore, the following series of processes stops upon receiving a stop command from the vehicle's driver via the input device 50.

[0035] First, in step S101, the acquisition unit 11 acquires map information, vehicle location information, and vehicle route information from the car navigation system 20.

[0036] Next, in step S102, the determination unit 12 determines, based on the map information and the vehicle's position information, whether the road the vehicle is traveling on has multiple lanes. If it is determined that the road the vehicle is traveling on has multiple lanes (YES in step S102), the process proceeds to step S103. On the other hand, if it is determined that the road the vehicle is traveling on does not have multiple lanes (NO in step S102), the process ends.

[0037] In step S103, the determination unit 12 also determines, based on the map information, the vehicle's position information, and the vehicle's route information, whether the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance. If it is determined that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance (YES in step S103), the process proceeds to step S104. On the other hand, if it is determined that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is not greater than or equal to a predetermined distance (NO in step S103), the process ends.

[0038] In step S104, the speed acquisition unit 14 acquires the vehicle's speed information from the speed sensor 40. Next, in step S105, the measurement unit 15 sets the measurement time interval T based on the vehicle's speed information. Next, in step S106, the image acquisition unit 13 acquires image information of the surroundings of the vehicle from the camera 30.

[0039] Next, in step S107, the measurement unit 15 measures, based on image information of the area around the vehicle, the difference between the number of other vehicles that have overtaken the vehicle (number 1) and the number of other vehicles that have been overtaken by the vehicle (number 2) for each of the multiple lanes on the road the vehicle is traveling in, at a predetermined time interval T.

[0040] Next, in step S108, the suggestion unit 16 determines whether there is a lane where the difference in the number of vehicles between the first and second vehicles is greater than or equal to the vehicle threshold A (provided that the first vehicle > second vehicle). If it is determined that there is a lane where the difference in the number of vehicles between the first and second vehicles is greater than or equal to the vehicle threshold A (YES in step S108), the process proceeds to step S109. On the other hand, if it is determined that there is no lane where the difference in the number of vehicles between the first and second vehicles is greater than or equal to the vehicle threshold A (NO in step S108), the process ends.

[0041] In step S109, the suggestion unit 16, via the output device 60, suggests to the driver of the vehicle that the lane in question is a recommended lane if the difference between the number of vehicles in the first lane and the number of vehicles in the second lane is equal to or greater than the vehicle threshold A. The recommended lane is a lane in which the flow of traffic is judged to be good.

[0042] Figure 3 shows an example of the screen of the output device 60, which includes recommended lanes suggested to the driver of the vehicle by the suggestion unit 16 of the driver assistance system 1 according to the first embodiment.

[0043] As shown in Figure 3, the road on which the vehicle is traveling includes multiple lanes X1, X2, X3, X4, and X5. The suggestion unit 16 suggests X3, X4, and X5 as recommended lanes from among the lanes X1 to X5. If there are multiple recommended lanes, the suggestion unit 16 may output multiple recommended lanes with assigned priorities. For example, the recommended lanes X3, X4, and X5 may be output with assigned priorities based on color or other factors.

[0044] Figure 4 shows another example of the screen of the output device 60, which includes recommended lanes suggested to the driver of the vehicle by the suggestion unit 16 of the driver assistance system 1 according to the first embodiment. As shown in Figure 4, the road on which the vehicle is traveling includes multiple lanes, Y1 and Y2. The vehicle is traveling in lane Y2. If the suggestion unit 16 determines that lane Y1 is the most promising recommended lane, it outputs an arrow indicating Y1, the recommended lane.

[0045] The driver assistance system 1 according to the first embodiment determines whether the road on which the vehicle is traveling is a road with multiple lanes. If the driver assistance system 1 determines that the road on which the vehicle is traveling is a road with multiple lanes, it measures the difference in the number of vehicles between the first number of vehicles that have overtaken the vehicle and the second number of vehicles that have been overtaken by the vehicle, based on image information captured around the vehicle, for each of the multiple lanes on the road on which the vehicle is traveling, at a predetermined time interval T. Based on the difference in the number of vehicles, the driver assistance system 1 determines a recommended lane from among the multiple lanes on the road on which the vehicle is traveling, which is the lane in which the vehicle is recommended to travel, and proposes the determined recommended lane to the driver of the vehicle. In this way, the driver assistance system 1 can automatically propose a lane change to the driver of the vehicle as a recommended lane, which is a lane in which the flow of traffic is judged to be good. Therefore, compared to changing lanes based on the driver's or passenger's visual observation and intuition, the stress placed on the driver of the vehicle can be reduced.

[0046] Furthermore, if the driver assistance system 1 determines that the road on which the vehicle is traveling has multiple lanes, it changes a predetermined time interval T according to the vehicle's speed. For example, the faster the vehicle's speed, the better the traffic flow in the lane the vehicle is traveling in, and if the traffic flow is good, it determines that a quick lane change is unnecessary and sets a longer time interval T. By doing so, the driver assistance system 1 can reduce the number of times it measures the difference in the number of vehicles between the first and second vehicles and suggests recommended lanes, thereby reducing the stress placed on the driver of the vehicle by unnecessary lane change suggestions.

[0047] Furthermore, if the driver assistance system 1 determines that the distance from the vehicle's current location to the junction where the vehicle plans to turn right or left is greater than a predetermined distance, it measures the difference in the number of vehicles between the first and second lanes at predetermined time intervals T for each of the multiple lanes provided on the road the vehicle is traveling on. When the vehicle is close to the junction where it plans to turn right or left, it often does not change lanes. The driver assistance system 1 only suggests a recommended lane when the vehicle is far from the junction where it plans to turn right or left. By doing so, the driver assistance system 1 can reduce the number of times it measures the difference in the number of vehicles between the first and second lanes and suggests a recommended lane, thereby further reducing the stress placed on the driver of the vehicle by unnecessary lane change suggestions.

[0048] (Second embodiment) Next, the configuration of the driver assistance system 2 according to the second embodiment will be described.

[0049] The driver assistance system 2 has the same components as the driver assistance system 1 according to the first embodiment. However, the driver assistance system 2 has the following additional functions of its components compared to the components of the driver assistance system 1.

[0050] The acquisition unit 11 acquires map information from the car navigation system 20. The acquired map information further includes information on the type of road set for each road. Road types include, for example, expressways, national roads, and general roads. The map information also includes information on the legal speed limit set for each road type.

[0051] The determination unit 12 determines the type of road the vehicle is traveling on based on map information and the vehicle's location information. For example, the determination unit 12 determines whether the type of road the vehicle is traveling on is an "expressway," a "national road," or a "general road."

[0052] The measurement unit 15 obtains information on the legal speed limit set for the type of road on which the vehicle is traveling from map information. The measurement unit 15 determines whether the time the vehicle has been traveling while the difference between the legal speed limit and the vehicle's speed is equal to or greater than a predetermined speed threshold B is equal to or greater than a predetermined time threshold C. Based on this determination result, the measurement unit 15 changes the start timing of the measurement of the difference in the number of vehicles between the first and second vehicles.

[0053] Specifically, the measurement unit 15 starts measuring the difference in the number of vehicles between the first and second vehicles if the vehicle's travel time while the difference between the legal speed and the vehicle's speed is equal to or greater than a predetermined speed threshold B is equal to or greater than a predetermined time threshold C. On the other hand, the measurement unit 15 does not start measuring the difference in the number of vehicles between the first and second vehicles if the vehicle's travel time while the difference between the legal speed and the vehicle's speed is equal to or greater than a predetermined speed threshold B is not equal to or greater than a predetermined time threshold C. In other words, the measurement unit 15 starts measuring the difference in the number of vehicles between the first and second vehicles if it determines that a quick lane change is necessary when the traffic flow in the lane the vehicle is traveling in remains poor. On the other hand, the measurement unit 15 does not start measuring the difference in the number of vehicles between the first and second vehicles if it determines that a quick lane change is unnecessary when the traffic flow in the lane the vehicle is traveling in remains good.

[0054] Furthermore, the measurement unit 15 determines the speed threshold B and the time threshold C according to the type of road. For example, on an expressway, the number of other vehicles that overtake your vehicle or the number of other vehicles that are overtaken by your vehicle will be greater than on an ordinary road. In this case, the suggestion unit 16 changes the speed threshold B and the time threshold C according to the type of road in order to reduce the influence of differences in vehicle flow due to the type of road on the determination of the recommended lane.

[0055] The proposal unit 16 determines the lane where the difference in the number of vehicles between the first and second lanes (however, the first number of vehicles > the second number of vehicles) is greater than or equal to a predetermined vehicle threshold A, that is, the lane where the flow of vehicles is judged to be good, as the recommended lane. Furthermore, the proposal unit 16 changes the vehicle threshold A according to the type of road. Here, the proposal unit 16 changes the vehicle threshold A according to the type of road in order to reduce the influence of differences in vehicle flow due to the type of road on the determination of the recommended lane.

[0056] Next, the operation of the driver assistance system 2 according to the second embodiment will be explained using Figures 5 and 6.

[0057] Figures 5 and 6 are flowcharts showing an example of the operation of the driver assistance system 2 according to the second embodiment.

[0058] As shown in Figures 5 and 6, the driver assistance system 2 starts the following series of processes upon receiving a start command from the driver of its own vehicle via the input device 50. The driver assistance system 2 also repeats the following series of processes at predetermined intervals. The driver assistance system 2 stops the following series of processes upon receiving a stop command from the driver of its own vehicle via the input device 50.

[0059] First, in step S201, the acquisition unit 11 of the driver assistance device 10 of the driver assistance system 2 acquires map information, vehicle location information, and vehicle route information from the car navigation system 20.

[0060] Next, in step S202, the determination unit 12 determines, based on the map information and the vehicle's position information, whether the road the vehicle is traveling on has multiple lanes. If it is determined that the road the vehicle is traveling on has multiple lanes (YES in step S202), the process proceeds to step S203. On the other hand, if it is determined that the road the vehicle is traveling on does not have multiple lanes (NO in step S202), the process ends.

[0061] In step S203, the determination unit 12 also determines, based on map information, the vehicle's position information, and the vehicle's route information, whether the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance. If it is determined that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance (YES in step S203), the process proceeds to step S204. On the other hand, if it is determined that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is not greater than or equal to a predetermined distance (YES in step S203), the process ends.

[0062] In step S204, the determination unit 12 determines the type of road the vehicle is traveling on based on the map information and the vehicle's location information. Here, the determination unit 12 determines whether the type of road the vehicle is traveling on is an "expressway," a "national road," or a "general road."

[0063] If it is determined in step S204 that the type of road the vehicle is traveling on is a "highway", the process proceeds to step S205. In step S205, the speed acquisition unit 14 acquires the vehicle's speed information from the speed sensor 40.

[0064] In step S206, the measurement unit 15 determines whether the time the vehicle has been traveling while the difference between the legal speed limit set for "expressway" and the vehicle's speed is equal to or greater than the speed threshold B1 is equal to or greater than the time threshold C1. If it is determined that the type of road the vehicle is traveling on is an "expressway", then for example, the speed threshold B1 is set to "20 km" and the time threshold C1 is set to "20 minutes". If it is determined that the time the vehicle has been traveling while the difference between the legal speed limit set for expressway and the vehicle's speed is equal to or greater than the speed threshold B1 is equal to or greater than the time threshold C1 (YES in step S206), the process proceeds to step S207. If it is determined that the time the vehicle has been traveling while the difference between the legal speed limit set for expressway and the vehicle's speed is equal to or greater than the speed threshold B1 is equal to or greater than the time threshold C1 (NO in step S206), the process ends.

[0065] In step S207, the measurement unit 15 starts the measurement process. Next, in step S208, the measurement unit 15 sets the measurement time interval T based on the vehicle's speed information. Next, in step S209, the image acquisition unit 13 acquires image information of the surroundings of the vehicle from the camera 30.

[0066] Next, in step S210, the measurement unit 15 measures, based on image information of the area around the vehicle, the difference between the number of other vehicles that have overtaken the vehicle (number 1) and the number of other vehicles that have been overtaken by the vehicle (number 2) for each of the multiple lanes on the road the vehicle is traveling in, at a predetermined time interval T.

[0067] Next, in step S211, the suggestion unit 16 determines whether there is a lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A1 (however, the first vehicle > second vehicle). Here, if it is determined that the type of road on which the vehicle is traveling is a "highway", for example, the vehicle threshold A1 is set to "10 vehicles". If it is determined that there is a lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A1 (YES in step S211), the process proceeds to step S212. On the other hand, if it is determined that there is no lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A1 (NO in step S211), the process ends.

[0068] In step S212, the suggestion unit 16, via the output device 60, suggests to the driver of the vehicle that the lane in question is a recommended lane if the difference between the number of vehicles in the first lane and the number of vehicles in the second lane is equal to or greater than the vehicle threshold A1.

[0069] Furthermore, if it is determined in step S204 that the type of road the vehicle is traveling on is a "national highway," the process proceeds to step S213. In step S213, the speed acquisition unit 14 acquires the vehicle's speed information from the speed sensor 40. Next, in step S214, the measurement unit 15 determines whether the time the vehicle has been traveling while the difference between the legal speed limit set for "national highway" and the vehicle's speed is equal to or greater than the speed threshold B2 is equal to or greater than the time threshold C2. Here, if it is determined that the type of road the vehicle is traveling on is a "national highway", for example, the speed threshold B2 is set to "15 km" and the time threshold C2 is set to "10 minutes". If it is determined that the time the vehicle has been traveling while the difference between the legal speed limit set for expressways and the vehicle's speed is equal to or greater than the speed threshold B2 is equal to or greater than the time threshold C2 (YES in step S214), the process proceeds to step S215. If it is determined that the time the vehicle has been traveling while the difference between the legal speed limit set for expressways and the vehicle's speed is equal to or greater than the speed threshold B2 is equal to or greater than the time threshold C2 (NO in step S214), the process ends.

[0070] In step S215, the measurement unit 15 starts the measurement process. Next, in step S216, the measurement unit 15 sets the measurement time interval T based on the vehicle's speed information. Next, in step S217, the image acquisition unit 13 acquires image information of the surroundings of the vehicle from the camera 30.

[0071] Next, in step S218, the measurement unit 15 measures, based on image information of the area around the vehicle, the difference between the number of other vehicles that have overtaken the vehicle (number 1) and the number of other vehicles that have been overtaken by the vehicle (number 2) for each of the multiple lanes on the road the vehicle is traveling in, at a predetermined time interval T.

[0072] Next, in step S219, the suggestion unit 16 determines whether there is a lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A2 (however, the first vehicle > second vehicle). Here, if it is determined that the type of road on which the vehicle is traveling is a "national highway", for example, the vehicle threshold A2 is set to "8 vehicles". If it is determined that there is a lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A2 (YES in step S219), the process proceeds to step S220. On the other hand, if it is determined that there is no lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A2 (NO in step S219), the process ends.

[0073] In step S220, the suggestion unit 16, via the output device 60, suggests to the driver of the vehicle that lane in question is a recommended lane if the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A2.

[0074] Furthermore, if it is determined in step S204 that the type of road on which the vehicle is traveling is a "general road," the process proceeds to step S221.

[0075] In step S221, the speed acquisition unit 14 acquires the vehicle's speed information from the speed sensor 40. Next, in step S222, the measurement unit 15 determines whether the time the vehicle has been traveling while the difference between the legal speed set for "general roads" and the vehicle's speed is equal to or greater than the speed threshold B3 is equal to or greater than the time threshold C3. Here, if it is determined that the type of road the vehicle is traveling on is "general road", for example, the speed threshold B3 is set to "10 km" and the time threshold C3 is set to "5 minutes". If it is determined that the time the vehicle has been traveling while the difference between the legal speed set for expressways and the vehicle's speed is equal to or greater than the speed threshold B3 is equal to or greater than the time threshold C3 (YES in step S222), the process proceeds to step S223. If it is determined that the time the vehicle has been traveling while the difference between the legal speed set for expressways and the vehicle's speed is equal to or greater than the speed threshold B3 is equal to or greater than the time threshold C3 (NO in step S222), the process ends.

[0076] In step S223, the measurement unit 15 starts the measurement process. Next, in step S224, the measurement unit 15 sets the measurement time interval T based on the vehicle's speed information. Next, in step S225, the image acquisition unit 13 acquires image information of the surroundings of the vehicle from the camera 30.

[0077] Next, in step S226, the measurement unit 15 measures, based on image information of the area around the vehicle, the difference between the number of other vehicles that have overtaken the vehicle (number 1) and the number of other vehicles that have been overtaken by the vehicle (number 2) for each of the multiple lanes on the road the vehicle is traveling in, at a predetermined time interval T.

[0078] Next, in step S227, the suggestion unit 16 determines whether there is a lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A3 (provided that the first vehicle > second vehicle). If it is determined that the type of road on which the vehicle is traveling is "general", then for example, the vehicle threshold A3 is set to "6 vehicles". If it is determined that there is a lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A3 (YES in step S227), the process proceeds to step S228. On the other hand, if it is determined that there is no lane where the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A3 (NO in step S227), the process ends.

[0079] In step S228, the suggestion unit 16, via the output device 60, suggests to the driver of the vehicle that lane in question is a recommended lane if the difference in the number of vehicles between the first and second vehicles is equal to or greater than the vehicle threshold A3.

[0080] The driver assistance system 2 according to the second embodiment provides the same effects as the driver assistance system 1 according to the first embodiment.

[0081] Furthermore, the driver assistance system 2 determines whether the time the vehicle has been traveling while the difference between the legal speed set for the road on which the vehicle is traveling and the vehicle's speed is equal to or greater than a predetermined speed threshold is equal to or greater than a predetermined time threshold. Based on this determination, the driver assistance system 2 changes the timing at which it starts measuring the difference in the number of vehicles between the first and second vehicles. Specifically, the driver assistance system 2 starts measuring the difference in the number of vehicles between the first and second vehicles if the time the vehicle has been traveling while the difference between the legal speed and the vehicle's speed is equal to or greater than a predetermined speed threshold B is equal to or greater than a predetermined time threshold C. On the other hand, the driver assistance system 2 does not start measuring the difference in the number of vehicles between the first and second vehicles if the time the vehicle has been traveling while the difference between the legal speed and the vehicle's speed is equal to or greater than a predetermined speed threshold B is not equal to or greater than a predetermined time threshold C. In other words, the driver assistance system 2 starts measuring the difference in the number of vehicles between the first and second vehicles if it determines that a quick lane change is necessary when the traffic flow in the lane on which the vehicle is traveling remains poor. On the other hand, if the traffic flow in the lane the vehicle is traveling in remains smooth, the driver assistance system 2 does not initiate measurement of the difference in the number of vehicles between the first and second lanes, as it deems a rapid lane change unnecessary. By doing so, the driver assistance system 2 can reduce the number of times it measures the difference in the number of vehicles between the first and second lanes and suggests recommended lanes, thereby further reducing the stress placed on the driver of the vehicle by unnecessary lane change suggestions. Furthermore, the driver assistance system 2 determines the speed threshold B and the time threshold C according to the type of road. By doing so, the driver assistance system 2 can reduce the influence of differences in vehicle flow due to road type on the determination of the recommended lane.

[0082] Furthermore, the driver assistance system 2 changes the vehicle threshold A, which is compared with the difference in the number of vehicles between the first and second vehicle counts, according to the type of road, in order to determine the recommended lane with good vehicle flow. By doing so, the driver assistance system 2 can reduce the influence of differences in vehicle flow due to the type of road on the determination of the recommended lane.

[0083] Although the present disclosure has been described above with reference to embodiments, the present disclosure is not limited to the embodiments described above. Various modifications to the structure and details of the present disclosure are possible, as can be understood by those skilled in the art within the scope of the present disclosure. Furthermore, each embodiment can be combined with other embodiments as appropriate.

[0084] Each drawing is merely illustrative to illustrate one or more embodiments. Each drawing may be associated with one or more other embodiments rather than with only one specific embodiment. As those skilled in the art will understand, various features or steps described with reference to any one drawing can be combined with features or steps shown in one or more other drawings, for example, to create embodiments not explicitly shown or described. Not all features or steps shown in any one drawing to illustrate an exemplary embodiment are necessarily required, and some features or steps may be omitted. The order of steps shown in any of the drawings may be changed as appropriate. [Explanation of Symbols]

[0085] 1. Driver assistance system 2. Driver assistance systems 10. Driving support systems 11 Acquisition Department 12 Judgment section 13 Image acquisition unit 14 Speed ​​acquisition section 15 Measurement section 16 Proposal Department 20 Car Navigation 30 Cameras 40 Speed ​​Sensor 50 Input devices 60 Output device

Claims

1. An acquisition unit that acquires map information including location information for each road and information on the number of lanes provided on each road, and location information of the vehicle itself. A determination unit that determines whether the road on which the vehicle is traveling is a road with multiple lanes, based on the map information and the location information of the vehicle, If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, an image acquisition unit acquires image information of the area around the vehicle. If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, the speed acquisition unit acquires the speed of the vehicle, A measuring unit measures, based on image information captured of the area around the vehicle, the difference between the number of other vehicles that overtook the vehicle (number 1) and the number of other vehicles that were overtaken by the vehicle (number 2) at predetermined time intervals for each of the multiple lanes on the road the vehicle is traveling in. Based on the difference in the number of vehicles, the system determines a recommended lane from among multiple lanes on the road on which the vehicle is traveling, and proposes the determined recommended lane to the driver of the vehicle. The aforementioned measuring unit is The predetermined time interval is changed according to the speed of the vehicle. Driving assistance system.

2. The acquisition unit is, The vehicle acquires information about the route from its current location to its destination. The determination unit, Based on the information of the aforementioned route, it is determined whether the distance from the vehicle's current location to the branching point where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance. The aforementioned measuring unit is If it is determined that the distance from the vehicle's current location to the junction where the vehicle is scheduled to turn right or left is greater than or equal to a predetermined distance, the difference in the number of vehicles between the first and second lanes is measured at predetermined time intervals for each of the multiple lanes provided on the road the vehicle is traveling on. The driving support device according to claim 1.

3. The aforementioned map information is This further includes information on the type of road set for each road, and information on the legal speed limit set for each type of road, The aforementioned measuring unit is Based on the map information and the location information of the vehicle, it is determined whether the time the vehicle has been traveling while the difference between the legal speed limit set for the road on which the vehicle is traveling and the speed of the vehicle is equal to or greater than a predetermined speed threshold is equal to or greater than a predetermined time threshold. Based on the judgment result, the start timing for measuring the difference in the number of units between the first and second units will be changed. The driving support device according to claim 1 or 2.

4. The aforementioned proposal section is, From among the multiple lanes provided on the road on which the vehicle is traveling, a lane whose difference in the number of vehicles is equal to or greater than a predetermined threshold is selected as a recommended lane, and the selected recommended lane is proposed to the driver of the vehicle. Based on the map information and the location information of the vehicle, the predetermined vehicle threshold is changed according to the road type set for the road on which the vehicle is traveling. The driving support device according to claim 3.

5. Computers Map information including location information for each road and information on the number of lanes provided on each road, and location information of the vehicle itself are acquired. Based on the map information and the location information of the vehicle, it is determined whether the road on which the vehicle is traveling is a road with multiple lanes. If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, then image information of the area around the vehicle is acquired. If it is determined that the road on which the vehicle is traveling is a road with multiple lanes, the speed of the vehicle is obtained. Based on image information captured around the vehicle, for each of the multiple lanes on the road the vehicle is traveling on, the difference between the number of other vehicles that have overtaken the vehicle (number 1) and the number of other vehicles that have been overtaken by the vehicle (number 2) is measured at predetermined time intervals that are changed according to the speed of the vehicle. Based on the difference in the number of vehicles, a recommended lane is determined from among the multiple lanes provided on the road on which the vehicle is traveling, and the determined recommended lane is proposed to the driver of the vehicle. Driving assistance methods.

Images