Vehicle control device

Abstract

To provide a vehicle control device capable of reducing discomfort of a driver due to provision of a driving support against the intension of the driver to the driver.SOLUTION: A vehicle control device comprises: a sensor for acquiring information related to a road including a lane L1 on which an own vehicle travels and information related to a behavior of the own vehicle; and a processor to which a driving support to suppress a deviation of the own vehicle to a second lane is provided when it is determined based on the information, that there is a high possibility of the own vehicle to deviate to the second lane adjacent to the first lane from the first lane on which the own vehicle currently travels. When it is detected that the own vehicle is traveling on a fast lane and also it is detected that another vehicle is approaching the own vehicle from behind the own vehicle on the first lane, the device executes processing to prohibit provision of the driving support, processing to interrupt the provision of the driving support, or processing to provide the driving support by degenerating.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vehicle control device that controls a vehicle so that, when it is determined that there is a high possibility that the vehicle will deviate from the lane in which it is currently traveling, driving assistance is provided to the driver of the vehicle to prevent the vehicle from deviating from the lane. [Background technology]

[0002] A vehicle control device has been proposed that controls a vehicle so that, when it is determined that there is a high possibility that the vehicle will deviate from the lane in which the vehicle is currently traveling (hereinafter referred to as the "first lane"), driving assistance for preventing the vehicle from deviating from the first lane is provided to the driver of the vehicle (see, for example, Patent Document 1 below). This vehicle control device (hereinafter referred to as the "conventional device") controls an alarm device so that an alarm sound is generated when it is determined that there is a high possibility that the vehicle will deviate from the first lane. Another vehicle control device proposed of this type is a device (automatic steering device) that controls a steering device so that the vehicle is positioned in the center of the first lane when it is determined that there is a high possibility that the vehicle will deviate from the first lane. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-96377 A Summary of the Invention

[0004] Here, a scene is assumed in which another vehicle approaches from behind the vehicle while the vehicle is traveling in the overtaking lane (first lane). In this scene, the driver of the vehicle may attempt to deviate the vehicle to the left (or right) from the first lane (to move the vehicle to the second lane adjacent to the first lane) in order to give way to the other vehicle (following vehicle). If the vehicle control device provides the above-mentioned driving assistance (alarm or automatic steering) against the driver's intention, the driver may find the driving assistance annoying.

[0005] An object of the present invention is to provide a vehicle control device that can reduce discomfort felt by the driver caused by driving assistance being provided to the driver against the driver's intention.

[0006] In order to solve the above problem, a vehicle control device (1) of the present invention includes a sensor (20) that acquires information about a road including a first lane (L1) on which a vehicle (V) is traveling and information about a behavior of the vehicle, and a processor (10) that executes a process of controlling the vehicle (V) so that a driving assistance for suppressing the vehicle from departing into a second lane (L2) adjacent to the first lane is provided to the driver of the vehicle when it is determined based on the information that there is a high possibility that the vehicle will deviate from the first lane into a second lane (L2) adjacent to the first lane. The sensor is capable of acquiring information about a vehicle (V1) traveling around the vehicle, and when the processor detects that the vehicle is traveling in an overtaking lane and that another vehicle is approaching the vehicle from behind in the first lane based on various information acquired from the sensor, the processor executes a process for prohibiting the provision of the driving assistance, a process for interrupting the provision of the driving assistance, or a process for providing the driving assistance in a degraded form.

[0007] When a vehicle is traveling in a passing lane and another vehicle approaches from behind, the driver of the vehicle is likely to move the vehicle into a lane adjacent to the passing lane in order to give way to the other vehicle. In view of this, the vehicle control device according to the present invention can prohibit or suspend the provision of the driving assistance in a scene in which another vehicle approaches from behind while the vehicle is traveling in the passing lane (hereinafter referred to as a "specific scene"). In addition, the vehicle control device may be capable of providing a reduced level of driving assistance in a specific scene, compared to other scenes (hereinafter referred to as a "normal scene"). For example, the vehicle control device changes various parameters (thresholds) related to the satisfaction or non-success of a condition for prohibiting the provision of driving assistance in a specific scene, compared to a normal scene. In addition, for example, the vehicle control device may change various parameters (thresholds) related to the satisfaction or non-success of a condition for suspending the provision of driving assistance in a specific scene, compared to a normal scene, in order to make the condition for prohibiting the provision of driving assistance more likely to be satisfied. Also, for example, the vehicle control device may reduce the degree of driving assistance (for example, the volume of the warning sound, the magnitude of the steering torque of the automatic steering) in a specific scene compared to a normal scene. According to the vehicle control device according to the present invention configured as described above, it is possible to reduce the discomfort of the driver caused by the driving assistance being provided to the driver against the driver's intention (the intention to deviate the vehicle from the lane). [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram of a vehicle control device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view showing (A) a scene in which lane departure prevention control is executed and (B) a scene in which lane departure prevention control is not executed. [Diagram 3] FIG. 3 is a flowchart of a program that realizes a function of determining whether or not to provide driving assistance depending on the scene (a function of determining a value to be assigned to a threshold value). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 1, a vehicle control device 1 (lane departure prevention device) according to one embodiment of the present invention is applied to a vehicle V (hereinafter referred to as "host vehicle") equipped with an automatic driving function. The vehicle control device 1 has a function (lane departure prevention function) of executing lane departure prevention control (automatic steering) for preventing the host vehicle from departing from the lane in which it is traveling when the automatic driving function is disabled (when the driver is actively performing driving operations).

[0010] (Specific Configuration) As shown in FIG. 1, the vehicle control device 1 includes an ECU 10, an on-vehicle sensor 20, and a steering device 30.

[0011] The ECU 10 includes a microcomputer including a CPU 10a, a ROM 10b, a RAM 10c, a timer 10d, etc. The ECU 10 is connected to other ECUs via a CAN (Controller Area Network).

[0012] The on-board sensors 20 include a radar 21 , a sonar 22 , an exterior camera 23 , a navigation system 24 , a speed sensor 25 , a steering sensor 26 and a driver sensor 27 .

[0013] The radar 21 includes a transmission / reception unit and a signal processing unit. The transmission / reception unit emits millimeter wave band radio waves (hereinafter referred to as "millimeter waves") to the surrounding area of ​​the vehicle and receives millimeter waves (reflected waves) reflected by three-dimensional objects (other vehicles, guard rails, poles, etc.) located within the emission range. The signal processing unit recognizes the distance between the vehicle and the three-dimensional object, the relative position (direction) of the three-dimensional object with respect to the vehicle, etc. based on the time from when the transmission / reception unit emits the millimeter waves to when it receives the reflected waves, the phase difference between the transmitted millimeter waves and the received reflected waves, the attenuation of the reflected waves, etc., and provides the recognition result to the ECU 10.

[0014] The sonar 22 intermittently emits ultrasonic waves to the surrounding area of ​​the vehicle and receives ultrasonic waves (reflected waves) reflected by a three-dimensional object. The sonar 22 recognizes the distance between the vehicle and the three-dimensional object, the relative position (direction) of the three-dimensional object with respect to the vehicle, etc. based on the time from when the ultrasonic waves are transmitted to when the reflected waves are received, and provides the recognition result to the ECU 10.

[0015] The exterior camera 23 includes an imaging device and an image analysis device. The imaging device has, for example, a built-in CCD. The imaging devices are installed at the front, rear, right side, and left side of the vehicle. Each imaging device captures a predetermined area around the vehicle at a predetermined frame rate to obtain image data. The image analysis device analyzes the image data obtained from each imaging device and recognizes objects existing around the vehicle from the images. For example, the image analysis device recognizes other vehicles, lane marks (division lines that divide driving lanes, curbs, medians, etc.), and provides the recognition results to the ECU 10.

[0016] Based on multiple GPS signals, the navigation system 24 acquires information about the vehicle's current location (latitude and longitude), direction of travel, information about the road including the lane on which the vehicle is traveling (the number of lanes that make up the road, the degree of curves), and the like, and provides this information to the ECU 10.

[0017] The speed sensor 25 acquires the speed vs of the host vehicle and provides it to the ECU 10 .

[0018] The steering sensor 26 detects the angle of rotation of the steering wheel by the driver (the angle (steering angle θ) between the neutral position and the current angular position) and provides the detected angle to the ECU 10 .

[0019] The driver sensor 27 includes an in-vehicle camera. The in-vehicle camera includes an imaging device and an image analysis device. The imaging device is installed on the dashboard of the vehicle. The imaging device captures images of the driver's face at a predetermined frame rate to obtain image data. The image analysis device analyzes the image data obtained from the imaging device, calculates the driver's alertness AR (or fatigue level) based on the image, and provides the calculation result to the ECU 10.

[0020] The steering device 30 adjusts the steering angle of the steering wheels (left front wheel and right front wheel). The steering device 30 includes a steering ECU and a steering mechanism. The steering device 30 further includes an actuator (e.g., an electric motor) that drives the steering mechanism to change the steering angle, and a steering angle sensor that acquires the steering angle (actual steering angle) of the steering wheels. The ECU 10 determines a target value of the steering angle (actual steering angle) of the steering wheels based on various information acquired from the on-board sensor 20. For example, when there is a high possibility that the host vehicle will deviate from the lane, the ECU 10 determines a target value of the steering angle so that the host vehicle is located in the center in the width direction of the lane. The steering ECU acquires the target value from the ECU 10 and controls the actuator so that the actual steering angle output from the steering angle sensor matches the target value.

[0021] (Lane Departure Suppression Control) Based on information acquired from the on-board sensor 20, the ECU 10 successively determines whether or not there is a high possibility of the host vehicle deviating from the lane L1 (see FIG. 2A and FIG. 2B) in which the host vehicle is traveling. Specifically, the ECU 10 acquires the position P of the host vehicle's center of gravity in the width direction of the lane L1 (amount of deviation to the right or left from the center in the width direction (lateral direction) of the lane L1), the degree of curvature of the lane L1, the curve direction, the width W of the lane L1, and the like, from the exterior camera 23 and the navigation system 24. The ECU 10 also acquires the speed vs and the steering angle θ from the speed sensor 25 and the steering sensor 26, respectively. Next, based on this information, the ECU 10 calculates the lateral speed vy of the host vehicle's center of gravity relative to the lane L1 (speed vector in the width direction of the lane L1). Next, the ECU 10 calculates (predicts) a time Δt required for the host vehicle to deviate from the lane L1 based on the speed vy, the position P, and the width W. Then, the ECU 10 determines that the host vehicle is highly likely to deviate from the lane L1 when the time Δt is less than a threshold value Δtth. In this case, the ECU 10 executes lane departure suppression control (driving assistance) that controls the steering device 30 so that the host vehicle is positioned in the center of the lane L1.

[0022] However, when the turn signal of the host vehicle is activated, even if the ECU 10 determines that the host vehicle is likely to deviate from the lane L1 in the direction indicated by the turn signal, the ECU 10 does not execute the lane departure suppression control. In other words, in this case, execution of the lane departure suppression control is prohibited.

[0023] In addition, even if the turn signal is not activated, if the speed vy is relatively high, there is a high possibility that the driver is intentionally causing the vehicle to deviate from the lane L1. Therefore, the ECU 10 does not execute lane departure suppression control if the following condition X is satisfied. [Condition X] The speed vy is greater than or equal to the threshold vyth.

[0024] Incidentally, in a scene where another vehicle V1 approaches from behind the host vehicle while the host vehicle is traveling in the passing lane (lane L1), the driver of the host vehicle is likely to intentionally deviate the host vehicle from lane L1 in order to yield to the other vehicle (the following vehicle). Therefore, the ECU10 sequentially determines whether the following condition Y is satisfied. [Condition Y] · The host vehicle is traveling in the passing lane. · The rate of decrease Δdr (absolute value) of the distance (inter-vehicle distance Δd) between the other vehicle V1 traveling immediately behind the host vehicle and the host vehicle is equal to or greater than the threshold value Δdrth. · It is possible to avoid (change lanes) the host vehicle to the lane L2 adjacent to the lane L1 (there are no other vehicles in the lateral region of the host vehicle and the regions of a predetermined length located before and after it). · The arousal level AR of the driver of the host vehicle is equal to or greater than the threshold value ARth.

[0025] In a scene where the condition Y is satisfied (a specific scene), the ECU10 lowers the threshold value vyth. That is, in a scene where the condition Y is not satisfied (a normal scene (FIG. 2A)), the ECU10 assigns a value vya that is relatively large compared to the threshold value vyth, and in a specific scene (FIG. 2B), it assigns a value vyb (<vya) that is relatively small compared to the threshold value vyth. As a result, in a specific scene, even in a situation where the speed vy is relatively low, the condition X is satisfied. That is, in a specific scene, compared to a normal scene, it becomes more difficult to execute the lane departure suppression control.

[0026] Next, with reference to FIG. 3, a program PR1 executed by the CPU10a of the ECU10 (hereinafter simply referred to as the "CPU") to realize a function of determining the value assigned to the threshold value vyth according to whether the condition Y is satisfied will be described.

[0027] The CPU executes the program PR1 at a predetermined cycle when the ignition switch of the host vehicle is in the ON state. The CPU starts the execution of the program PR1 from step 100 and proceeds to step 101.

[0028] In step 101, the CPU determines whether or not the host vehicle is traveling in the passing lane based on information acquired from the navigation system 24. If the CPU determines that the host vehicle is traveling in the passing lane (101: Yes), the CPU proceeds to step 102. On the other hand, if the CPU does not determine that the host vehicle is traveling in the passing lane (101: No), the CPU proceeds to step 106.

[0029] In step 102, the CPU determines whether the decrease rate Δdr (absolute value) of the inter-vehicle distance Δd is equal to or greater than a threshold Δdrth. If the CPU determines that the decrease rate Δdr is equal to or greater than the threshold Δdrth (102: Yes), the CPU proceeds to step 103. If the CPU does not determine that the decrease rate Δdr is equal to or greater than the threshold Δdrth (102: No), the CPU proceeds to step 106.

[0030] In step 103, the CPU determines whether or not the host vehicle can be evacuated to lane L2. If the CPU determines that the host vehicle can be evacuated to lane L2 (103: Yes), the CPU proceeds to step 104. On the other hand, if the CPU does not determine that the host vehicle can be evacuated to lane L2 (103: No), the CPU proceeds to step 106.

[0031] In step 104, the CPU determines whether the wakefulness AR is equal to or greater than the threshold value ARth. If the CPU determines that the wakefulness AR is equal to or greater than the threshold value ARth (104: Yes), the CPU proceeds to step 105. On the other hand, if the CPU does not determine that the wakefulness AR is equal to or greater than the threshold value ARth (104: No), the CPU proceeds to step 106.

[0032] If the CPU advances the process to step 105, it assigns a relatively small value vyb to the threshold value vyth. If the CPU advances the process to step 106, it assigns a relatively large value vya to the threshold value vyth. Then, the CPU advances the process to step 107, where it ends the execution of the program PR1.

[0033] (Effect) As described above, the vehicle control device 1 is configured to make it more difficult to execute lane departure suppression control in a specific scene where condition Y is satisfied, compared to a normal scene. This makes it possible to reduce discomfort felt by the driver in a specific scene, caused by the driver being provided with driving assistance contrary to the driver's intention (the intention to cause the vehicle to deviate from the lane).

[0034] <Modification 1> The ECU 10 may suspend (override) the execution of the lane departure prevention control when a predetermined condition Z is satisfied after the execution of the lane departure prevention control is started. The condition Z is satisfied, for example, when the rate of change θr of the steering angle θ is equal to or greater than the threshold value θrth while the lane departure prevention control is being executed. In this example, the ECU 10 assigns a smaller value to the threshold value θrth in a specific scene where the condition Y is satisfied while the lane departure prevention control is being executed, compared to a normal scene. This allows the driver to suspend the lane departure prevention control by turning the steering wheel relatively gently in the specific scene. In other words, even if the lane departure prevention control is started against the driver's intention, the driver can suspend the lane departure prevention control by a simple operation, so that the discomfort of the driver is low.

[0035] <Modification 2> In the above embodiment, when there is a high possibility that the host vehicle will deviate from the lane L1, the vehicle control device 1 controls the steering device 30 so as to suppress the deviation. The mode of driving assistance is not limited to this. For example, the vehicle control device 1 may control the alarm device so as to issue an alarm in the scene. The driver corrects the steering angle θ in response to this alarm, thereby suppressing the host vehicle from deviating from the lane L1. Also, in this example, the ECU 10 may prohibit an alarm in a specific scene where the condition Y is satisfied, regardless of whether the condition X is satisfied or not. Also, instead of prohibiting an alarm in the specific scene, the volume of the alarm sound may be reduced compared to the normal scene. That is, the ECU 10 may provide a reduced driving assistance in the specific scene compared to the normal scene.

[0036] <Modification 3> The vehicle control device 1 may be configured such that, when condition Y is satisfied, execution of lane departure suppression control is prohibited regardless of whether condition X is satisfied or not.

[0037] <Modification 4> In the above embodiment, condition X is satisfied when the lateral speed vy of the host vehicle is equal to or greater than a threshold value vyth. Alternatively, condition X may be satisfied when the rate of change (acceleration) of speed vy, steering angle θ, rate of change of steering angle θ, etc. are equal to or greater than threshold values. In this case, ECU 10 may lower those threshold values ​​when condition Y is satisfied. [Explanation of symbols]

[0038] 1...vehicle control device, 10...ECU, 20...vehicle-mounted sensor, 30...steering device

Claims

[Claim 1] A sensor for acquiring information regarding a road including a first lane on which the host vehicle is traveling and information regarding a behavior of the host vehicle; a processor that is capable of executing a process of controlling the host vehicle so that, when it is determined based on the information that there is a high possibility that the host vehicle will deviate from the first lane to a second lane adjacent to the first lane, a driving assistance for suppressing the host vehicle from deviating into the second lane is provided to a driver of the host vehicle; A vehicle control device comprising: The sensor is capable of acquiring information about vehicles traveling around the host vehicle, When the processor detects that the host vehicle is traveling in an overtaking lane and detects that another vehicle is approaching the host vehicle from behind in the first lane based on various information acquired from the sensor, the processor executes a process for prohibiting the provision of the driving assistance, a process for suspending the provision of the driving assistance, or a process for providing the driving assistance in a degraded manner. A vehicle control device configured as above.

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