JP2022169405A - Vehicle driving support device - Google Patents

Abstract

To make it possible to provide a support with a more appropriate content according to a driving characteristic of a driver and in consideration of a support acceptability of the driver in a driving support technique to avoid contact with a risk target such as a pedestrian.SOLUTION: A vehicle driving support device acquires driving type information predetermined based on a characteristic in driving by a driver for avoiding a risk target, determines to provide driving support in a different mode according to the driving type information when detecting the risk target on a side of a road in a traveling direction of the vehicle, and executes the determined mode of driving support.SELECTED DRAWING: Figure 6

Description

Application for application of Article 30, Paragraph 2 of the Patent Law Issuer name: Society of Automotive Engineers of Japan, Publication name: 2020 Autumn Conference Scientific Lecture Preprints Literature number: 20206052 No. 119-20 p. 1-6, Publication date: October 16, 2020 (Publications, etc.) Society of Automotive Engineers of Japan 2020 Autumn Meeting October 21, 2020

TECHNICAL FIELD The present invention relates to driving assistance technology for vehicles such as automobiles, and more particularly, when there is an object on the side of the road that may come into contact with a moving vehicle, such as a pedestrian or a bicycle, the collision is avoided. It relates to a device that provides driving assistance for

As a driving support technology for vehicles such as automobiles, objects that may come into contact with the vehicle, such as pedestrians, bicycles, parked vehicles, and other obstacles (hereinafter referred to as "risk targets") ) exists, various proposals have been made to urge the driver to steer or decelerate the vehicle, or to automatically steer or decelerate the vehicle in order to avoid contact with the risk object. It is For example, in Patent Document 1, the time to collision (TTC) until the vehicle contacts an object in front of the vehicle is a predetermined time or less, and the lateral distance between the object and the vehicle is a predetermined distance or less. A device is disclosed that warns the driver when the vehicle enters a certain extended warning area and the driver does not perform an avoidance operation such as a braking operation or a steering operation. Further, in Patent Document 2, when the vehicle approaches and passes through an object in front of the vehicle while the vehicle is running, the distance in the vehicle width direction between the vehicle and the object at the start of steering to avoid contact with the object ( side distance), the clearance distance for approaching the object, and the vehicle speed when passing the object sideways are collected, and from these data, the tendency of the driver's driving operation when avoiding the object is estimated. Next, when approaching and passing an object in front of the vehicle, the driver is instructed to steer according to the side distance and the clearance based on the estimated tendency of the driver's driving operation. A configuration is disclosed for determining the timing of providing driving assistance by providing information prompting the driver to perform driving assistance, applying a reaction force to the steering wheel, or operating a steering actuator to intervene in steering by the driver.

JP 2012-48460 JP 2015-130069

By the way, in general, the manner or mode of driving a vehicle differs from driver to driver, and there are also variations in driving operations for avoiding contact with risk targets such as pedestrians. In fact, the risk sensitivity (degree of risk of contact) and situational awareness/judgment for the risk object differ depending on the driver. The quality and timing of evasive maneuvers also differ depending on the driver. Therefore, it would be preferable if the driving assistance technology for avoiding contact with a risk target could change the content of the driving assistance more appropriately according to the characteristics of the driver's driving. Conversely, if the content of the provided driving assistance is difficult for the driver to accept, that is, if the driver feels annoyed or uneasy about the driving assistance, the driver may decide not to operate the driving assistance. In some cases, the vehicle may stop, and in such a case, the long-awaited driving assistance will not be provided.

Thus, one object of the present invention is to provide driving assistance technology for avoiding contact with risk objects such as pedestrians, in accordance with the driver's driving characteristics and the acceptability of the driver's assistance. It is to be able to provide support with more appropriate content in consideration of

In this regard, according to research by the inventors of the present invention, in driving to avoid a risk object, the characteristics of the driving, namely, the timing of the start of the avoidance action, the side passage of the risk object, Drivers can be classified into several types (types) based on vehicle speed, lateral distance, etc., and each type of driver (hereinafter referred to as "driving type") has a risk target. It became clear that there are driving tendencies (steering or braking, etc.) that are easy to take when avoiding. Therefore, when providing driving assistance for avoiding risky objects, the assistance should be provided in a form that is easy for the driver to accept, according to the driving type and in accordance with the tendency of driving that is easy to take for each driving type. If it is, it is considered that the driver will enjoy the assistance without feeling annoyed or anxious about the driving assistance. This knowledge is utilized in the present invention.

According to the present invention, the above problem is solved by a driving support device for a vehicle,
a driving type information acquisition means for acquiring driving type information of the driver determined in advance based on characteristics of the driver of the vehicle during driving for risk object avoidance;
risk object detection means for detecting a risk object on the side of the road in the traveling direction of the vehicle;
When the risk target is detected, the driving support mode determination means determines a driving support mode for avoiding the risk target, and provides different modes of driving support according to the acquired driving type of the driver. means for deciding to provide;
driving assistance execution means for executing the determined driving assistance mode.

In the above configuration, the "risk object" may be pedestrians, bicycles, parked vehicles, and various other obstacles, as already mentioned. "Driver's driving type information" refers to information about the driver's driving behavior, including steering and braking operations to avoid risks when there is a risk object in the direction of travel of the vehicle. This is information on the driving type when the drivers are classified into types based on the characteristics of the operation, for example, the steering is the main or the braking is the main. Data related to the driving situation collected when the driver avoids the actual risk target, or when the driver uses a simulated driving device such as a driving simulator to avoid the risk target, for example, It can be determined by the start time of evasive action, the minimum vehicle speed when passing the risk object sideways, the sideways distance, and the like. "Risk object detection means" is any means that can detect the situation around the vehicle, such as an in-vehicle camera or a radar device, or from the information around the vehicle obtained by a GPS device, etc. It may be a means for detecting a risk object such as a pedestrian present in the road. The 'driving assistance determining means' determines to provide different forms of driving assistance according to the driving type acquired by the driving type information acquiring means. "Mode of driving assistance" refers to the time to start providing driving assistance after the risk object is detected, the content of the driving assistance to be provided, for example, how to assist avoidance by steering, and how to assist avoidance by braking. "Driving assistance in a different manner depending on the acquired driving type of the driver" means that steering and braking are performed in a manner suitable for each driving type. is set for driving assistance. Then, the 'driving assistance execution means' instructs the driver to perform driving operations using an HMI (Human Machine Interface) device by voice or visual display so that the driving assistance is provided in the determined manner. It is configured to give a control command to each device of the vehicle in order to provide information, change the steering force of the steering wheel or the stepping force of the pedal, and execute automatic steering control and automatic braking control.

According to the device of the present invention described above, when providing driving assistance for avoiding a risk object, the driving characteristics of each driver when avoiding the risk object, for example, steering mainly for avoiding the risk object or braking is used, and the driving assistance is adapted to the characteristics, in other words, in a manner that the driver can easily accept without feeling annoyed or uneasy. is attempted to provide According to such a configuration, it is expected that the situation in which the driver stops the operation of the driving assistance because the driver feels that the driving assistance provided is unnecessary. can be more reliably enjoyed by the driver.

Regarding the classification of the "driving type" of the driver in the configuration of the device of the present invention, more specifically, according to research by the inventors of the present invention, which will be described later, the driving type of the driver is: It has been shown that the characteristics of driving when avoiding a risk target can be determined based on the start time of the avoidance action, the minimum vehicle speed when passing the risk target on the side, and the lateral distance when passing the risk target on the side. there is Here, the start timing of the avoidance action is the time from the time when the vehicle is expected to reach the side of the risk target to the time when braking or steering for avoidance of the risk target is executed, that is, the avoidance action is started. The length of time between the start and the time the vehicle is expected to reach the side of the object at risk (for which no collision actually occurs, but Since TTC is commonly used, this length of time is also referred to as TTC in this specification.). The minimum vehicle speed when passing the side of the risk object may be the minimum speed detected while the vehicle is passing the side of the risk object. The lateral distance when passing the side of the risk object is the distance between the side of the vehicle on the side of the risk object and the side of the vehicle on the side of the risk object in the lateral direction of the vehicle when the vehicle passes the side of the risk object. measured by the distance between Specifically, when each driver drives to avoid a risk target, (1) the TTC representing the start timing of the avoidance action exceeds a predetermined time (for example, 4 seconds), ( 2) The vehicle speed when passing the side of the risk object is below a predetermined vehicle speed (for example, 30 km/h); .5m) were each satisfied or not, and among these conditions, if the number of satisfied conditions is one or less, the first type is the satisfied condition If the number of is two or more, classifying it as the second type, distinguish the tendency of driving to avoid risk objects in each of the first type and the second type. It was possible to capture

Therefore, in the above-described device of the present invention, the driving type of the vehicle driver is classified into the first type and the second type based on the characteristics obtained during driving for risk object avoidance as described above. etc., and when driving a vehicle that provides driving assistance, for each driving type of the driver, the tendency of driving to avoid each risk object is determined. Adaptively configured aspects of driving assistance may be provided. The conditions referred to for determining the driving type are not limited to those described above, and may be appropriately selected through experiments or the like. Also, the predetermined values (predetermined time, predetermined speed, predetermined distance, etc.) referred to for determination of each condition may be set through experiments or the like through adaptation.

As already mentioned, the driver's driving type is determined based on the detection results obtained from simulated driving using a simulated driving device such as a driving simulator, or the detection results obtained from actual driving to avoid risks of the vehicle. In that case, in order to suppress variations in determination, it is preferable to use condition values measured when a specific running state, which may be appropriately set, is established. Specifically, for example, (a) a straight road section without a median line (road width of about 3m to 5m), (b) initial speed (running speed before encountering risk) (about 40km/h to 50km/h) , (c) when there is no vehicle in the oncoming lane, detection of the condition value for determining the driving type may be performed. However, it is not limited to this, and an appropriate state may be set as appropriate.

Specifically, the driving assistance provided by the device of the present invention includes, as described above, provision of driving operation information, change in steering force of the steering wheel or pedaling force, automatic steering control, automatic braking control, and the like. Where possible, particularly in the device of the present invention, the content of driving assistance is changed according to the driving type of the driver. For example, in driving to avoid risk objects, in the case of a driving type that mainly uses steering, it provides driving assistance that mainly uses steering, and in the case of a driving type that mainly uses braking. , the mode of driving assistance may be set so as to provide driving assistance focused on braking.

Regarding this point, according to research by the inventors of the present invention, etc., which will be explained later, when the driving type is the first type, when driving to avoid risky objects, steering is often performed mainly. Specifically, the steering is performed before the braking operation, and depending on the type of risk target (children's pedestrians, adult pedestrians, bicycles, etc.), the side distance when passing the side of the risk target is Experimental results show that there is a slight difference, and that the minimum vehicle speed when passing on the side of the risk target is not significantly affected by the width of the road. On the other hand, according to the same research, when the driving type is the second type, when driving to avoid risky objects, braking is often the main focus. Specifically, braking precedes steering. After executing the operation, there was no significant difference in the lateral distance when passing the side of the risk object depending on the type of risk object, and the minimum vehicle speed when passing the side of the risk object was Experimental results show that the road is lower than the wide road.

Therefore, in the embodiment of the device of the present invention, for example, when the driving type is the first type, when the risk object is detected, the target side distance when the risk object passes sideways is calculated. The value is variably set according to the type of the detected risk object, and the target value of the minimum vehicle speed when the risk object passes sideways is set to a safe value regardless of the width of the road. While the driving assistance for steering and braking is executed so that the target value of The target value for the side distance of is set to a safe value regardless of the type of the detected risk object, and the target value for the minimum vehicle speed when passing the risk object sideways is set according to the width of the road. Variable settings may be made and driving assistance for steering and braking may be carried out so that their target values are achieved. Further, the timing for starting driving assistance may be appropriately set in accordance with the timing (TTC) for starting avoidance action in each driving type. In addition, according to research, it has been found that the second type tends to start evasive behavior earlier than the first type, so in the case of the second type, , the driving assistance for braking may be started, and in the case of the first type, the driving assistance for steering may be started from time to time.

By the way, it is conceivable that the avoidance action of the risk object will change regardless of the driving type of the driver, depending on whether there is an oncoming vehicle or not when avoiding the risk object. Regarding this point, according to the research by the inventors of the present invention, which will be explained later, the tendency to use braking became stronger in any driving type, but the tendency to use braking before and after passing an oncoming vehicle became stronger. No significant change was observed in any of the driving types with respect to which way the vehicle passed the side of the risk target. From this, it can be said that the presence or absence of an oncoming vehicle need not be taken into consideration so much when determining the mode of driving assistance to be provided in each of the first type and the second type. Therefore, based on the results of the above research, in the configuration that determines the mode of driving assistance according to the first type and the second type, regardless of whether or not there is an oncoming vehicle, it is not always possible to change the configuration. It is not essential, therefore, it is advantageous in that the control configuration can be simplified (in order to set the mode of driving assistance more strictly, the presence or absence of an oncoming vehicle may be taken into consideration, and in that case also, the present invention can be applied). range should be understood).

Thus, according to the above-described device of the present invention, driving assistance is provided in a manner that is easy for the driver to accept in accordance with the driving characteristics of the driver. It is expected that the feeling of anxiety and anxiety will be reduced, thereby reducing the situation in which the operation of driving support is stopped. In the embodiments exemplified below, the number of driving types to be determined is two in the configuration for determining the mode of driving assistance for each driving type of the driver, but it is further subdivided into The mode of driving assistance to be provided may also be subdivided and set to suit each type. As described above, the form of driving assistance provided may be operation guidance for executing a preferable driving operation by providing information from the HMI device, automatic steering control, or automatic braking control. Alternatively, it may be both, and it should be understood that both cases are within the scope of the present invention.

Other objects and advantages of the present invention will become apparent from the following description of preferred embodiments of the invention.

FIG. 1(A) is a schematic diagram of a vehicle equipped with a preferred embodiment of a vehicle driving assistance device according to the present invention. FIG. 1B is a block diagram showing the configuration of a system in one embodiment of a vehicle driving support system according to the present invention. FIGS. 2A and 2B show the positional relationship between the vehicle and the risk target, which explain the parameters referred to when determining the driving type of the driver in the vehicle driving support system of the present embodiment. It is a representation figure. FIG. 3(A) is a diagram showing the frequency distribution for each driving type of the start timing of the operation for avoiding the risk object in an experiment investigating driving tendencies during driving to avoid the risk object. . FIG. 3B is a diagram showing the ratio of operations performed to avoid risky objects by driving type and road type in an experiment investigating driving tendencies during driving to avoid risky objects. The numbers in the figure are the percentage frequency of each item. Fig. 4 (A) shows the average value of the side distance when the risk object passes sideways for each type of risk object by driving type in an experiment investigating driving tendencies during driving to avoid the risk object. It is a figure which shows (circle) and a standard deviation (error bar). Figure 4 (B) shows the average minimum vehicle speed (○ ) and standard deviation (error bars). Figure 5 (A) and (B) show, in an experiment investigating driving tendencies during driving to avoid risky objects, an oncoming vehicle was detected before passing a risky object by driving type and by road type. The distribution of the positions of oncoming vehicles when the own vehicle passes the side of the risk target is shown in each of the situations in which the oncoming vehicle passes in the vicinity and in which the oncoming vehicle can be seen in the distance in the direction of travel. In the figure, 0 on the horizontal axis is the state where the vehicle passes the oncoming vehicle when passing the risk target side, and + is the state where the oncoming vehicle is in front of the vehicle when the risk target is passing sideways - is the state in which the oncoming vehicle is behind the own vehicle when the risk target passes sideways (passing the oncoming vehicle first). FIG. 6 is a diagram showing, in the form of a flowchart, an example of processing for determining and executing a driving assistance mode for each driving type in the vehicle driving assistance device of the present embodiment.

DESCRIPTION OF SYMBOLS 10... Vehicle 12 FL, FR, RL, RR... Wheel 28... Differential gear 30... Steering gear 32... Steering wheel 34... Steering booster 36R, L... Tie rod 40... Braking device 42... Wheel cylinder 44... Brake pedal 45... Master Cylinder 46 Hydraulic circuit 60 Electronic control unit 62 Yaw rate, lateral acceleration sensor 65 Longitudinal acceleration sensor 70 On-vehicle camera 72 On-vehicle radar device 74 GPS device

Vehicle Configuration Referring to FIG. 1A, in a vehicle 10 such as an automobile in which a preferred embodiment of the driving assistance system of the present invention is incorporated, the left and right front wheels 12FL and 12FR and the left and right front wheels 12FL and 12FR are arranged in a normal manner. Rear wheels 12RL, 12RR, drive system device (only some ), a steering device 30 for controlling the steering angle of the front wheels (a steering device for the rear wheels may also be provided), and a braking system device 40 for generating braking force on each wheel. to be installed. The driveline system operates in the usual manner from an engine and/or electric motor (not shown; it may be a hybrid drive system having both an engine and an electric motor) to a transmission (not shown). , through a differential gear device 28, driving torque or rotational force is transmitted to the rear wheels 12RL, 12RR. The steering device 30 transmits the rotation of a steering wheel (steering wheel) 32 actuated by the driver to tie rods 36L and R while boosting the rotational torque by a booster 34 to steer the front wheels 12FL and 10FR. A power steering device may be employed. In particular, in this embodiment, automatic steering control may be executed as one mode of driving assistance after the detection of the risk object on the side of the road. A structure capable of applying steering torque or controlling a turning angle based on a command from the device 60 may be employed.

The braking system 40 operates wheel cylinders 42i (i=FL, FR, RL , RR and so on), that is, the braking force at each wheel is adjusted. Hydraulic circuit 46 includes various valves (master cylinder cut valve, hydraulic holding valve, etc.) that selectively connect the wheel cylinders of each wheel to a master cylinder, an oil pump, or an oil reservoir (not shown) in a conventional manner. , pressure reducing valves) are provided, and in normal operation, in response to depression of the brake pedal 44, pressure from the master cylinder 45 is supplied to the respective wheel cylinders 42i. In particular, in this embodiment, automatic braking control may be executed as one mode of driving assistance after the detection of the risk object on the side of the road. braking force can be generated by applying brake pressure to the wheel cylinder 42i of each wheel based on the command of . The braking system device 40 may be of a type that pneumatically or electromagnetically applies a braking force to each wheel, or any other type for those skilled in the art.

In addition, in the vehicle 10 to which the preferred embodiment of the driving support control system of the present invention is applied, an in-vehicle camera 70 and a radar device 72 for detecting the situation around the vehicle are provided. (Pedestrians, bicycles), obstacles, parked vehicles, etc. can be detected, the type can be identified, the distance to the object in the direction of travel, the distance in the lateral direction (side distance), and the relative speed can be detected. The type, for example, the width of the road and the presence or absence of the median line may be recognized. A GPS device (car navigation system) 74 may be provided that communicates with GPS satellites and acquires various information such as the surrounding conditions and position information of the own vehicle.

The operation control of each part of the vehicle and the operation control of the driving support system according to the present embodiment are executed by the electronic control unit 60 . The electronic control unit 60 may include a microcomputer and drive circuits of conventional type having a CPU, ROM, RAM and input/output port devices interconnected by a bi-directional common bus. The configuration and operation of each part of the driving support system of this embodiment, which will be described later, may be realized by the operation of an electronic control unit (computer) 60 according to a program. The electronic control unit 60 includes information s1 to s3 from an in-vehicle camera 70, a radar device 72, a GPS device 74, etc., a steering angle θ, a brake pedal depression amount θb, a detection value ax of the front and rear G sensors 65, a wheel speed Vwi (i=FL, FR, RL, RR), etc., detected values from various sensors used as parameters for driving assistance of the present embodiment executed in a manner described later are input, and as driving assistance, driving A control command to an HMI device that provides operation advice to a person, or a control command representing a control amount in automatic steering control or automatic braking control, or the like is output to a corresponding device. Various parameters necessary for various controls to be executed in the vehicle of this embodiment, for example, various detection signals such as the yaw rate γ and/or the lateral acceleration Yg from the gyro sensor 62 are input, and various of control commands may be output to corresponding devices. Furthermore, as will be explained later, an input device for inputting the driver's driving type information to the electronic control unit 60, for example, a device that accepts input from a touch panel of a navigation device, a smartphone, etc., may be provided.

Device Configuration Referring to FIG. 1B, the driving support system according to the present embodiment generally includes a driving type acquisition section, a risk object detection section, a support mode determination section, and a driving support control execution section.

More specifically, the driving type acquisition unit, as will be described in detail later, classifies the driving tendency of the vehicle driver into types based on the respective characteristics of driving during avoidance of the risk object. It functions to obtain information about the driver's type (driving type). Determination of the driving type of the driver is performed in advance based on the characteristics of the operation detected when the risk target avoidance operation is performed under predetermined conditions. The avoidance operation of the risk target for determining the driving type may be performed by a simulated driving device such as a driving simulator, or may be performed while the vehicle is actually running. There may be. The driving type information may be acquired from any device that inputs driving type information, such as an input terminal of a navigation device or an input device capable of receiving information from a smartphone, as shown in the figure, or may be acquired from an in-vehicle device. (for example, driving type information determined based on the characteristics of the operation during the avoidance operation of the risk target acquired during the previous run) stored in advance in the storage device.

The risk object detection unit selects objects in the vicinity of the vehicle recognized in an arbitrary manner by the environment recognition device from information such as an image representing the situation in the vicinity of the vehicle, such as an in-vehicle camera 70 and a radar device 72, and detects the progress of the vehicle. When there is an object on the side of the road ahead of the vehicle that may come into contact with the vehicle, the object is detected as a risk object, and furthermore, the type of the risk object and the distance from the vehicle in the direction of travel of the vehicle are detected. relative distance of the risk object, relative velocity, lateral distance, which is the relative distance of the risk object from the side of the vehicle in the lateral direction of the vehicle, and the like. Positional information such as the existence and types of risk targets and relative distances can be detected in any manner. Pedestrians (adults and children), bicycles, parked vehicles, various stationary objects, and the like may be objects at risk.

The assistance mode determination unit refers to the driving type information from the driving type acquisition unit and the risk object information from the risk object detection unit, and determines the driving assistance provided for the avoidance operation of the risk object as will be described later. , different modes of driving assistance are determined depending on the driving type of the driver. In the form of driving assistance provided, specifically, the start time of driving assistance, the target value of vehicle speed or deceleration in braking assistance, the lateral distance between the risk object in steering assistance or the target value of the steering angle may be set at different timings or values depending on the driving type of the driver.

The driving support control execution unit, in accordance with the driving support start timing and the content of the driving support determined by the support mode determination unit, determines the location information of the risk target, the state quantity of the vehicle (vehicle speed, acceleration/deceleration, yaw rate, etc.), While referring to the steering angle of the steering wheel and the amount of depression of the brake pedal, it is configured to give a control command to the HMI device, the braking control device, or the steering control device in order to execute driving assistance. One form of driving assistance that is provided is that the HMI device provides the driver with audio or visual indications (image , lights on) to provide maneuver advice (steering, brake pedal depression, etc.). Also, the response of the braking control system or the steering control system may be changed to guide the driver's operation to achieve a target value in the maneuver for avoiding the risk object (e.g., the steering target such as changing the steering reaction force of the steering wheel according to the steering direction so that it approaches the value). Further, a control command may be given to automatically operate the braking control device or the steering control device in order to achieve the target value in the operation for avoiding the risk object. In that case, automatic braking control or automatic steering control may be performed in any manner to achieve the respective target values.

Device Operation (1) Overview As already described, in the device of the present embodiment, in driving assistance provided to assist driving for avoidance of risk objects, the driver In order to prevent the driver from feeling annoyed or anxious about the driving assistance, the assistance is provided in a mode according to the driving tendency of the driver. In this regard, as already mentioned, the inventors of the present invention, in their research on the tendency of driving to avoid risky objects, found that the tendency of a driver to drive is a risk factor under given conditions. Based on the amount related to the characteristics of driving detected when avoiding the object, it is possible to classify driving types, and it was found that each driving type can be grasped. Therefore, in this embodiment, based on the knowledge obtained from research on the tendency of driving to avoid such risk objects, driving assistance is provided so that it is easier to accept driving assistance for each driving type. is selected. In the following, knowledge obtained from research on the tendency of driving to avoid risky objects by the inventors of the present invention and specific processing operations of the device of the present embodiment will be described.

(2) Experimental Findings In order to investigate the tendency of driving to avoid the risk object, the inventors of the present invention conducted a driving simulator in which the risk object was present on the side of the road in various situations. We asked the subjects to simulate driving of a vehicle that overtakes the target while avoiding it, measured the driving operation (steering, braking operation) and the running position of the vehicle at that time, and analyzed the results. In the experiment, the subject was given an image (resolution: 4K (4096 x 2160 pixels)) of a situation in which the presence and situation of pedestrians and oncoming vehicles about 100m away in the driving simulator can be fully recognized. While watching, the driver was asked to drive the vehicle while avoiding pedestrians and the like. A road with a center line (hereinafter referred to as road type A) and a road without a center line (hereinafter referred to as road type B) were used as the roads shown in the image. Both roads do not have sidewalks separated by curbs or guardrails, but have roadside strips marked with lines outside the roadway. , Road type B has a one-sided road width of 3.0 m and a side strip width of 0.75 m. The center line of road type A is a dashed line, and it is possible to run on the right side. Children (moving at a speed of 4 km/h), adults (moving at a speed of 5 km/h), and bicycles (moving at a speed of 10 km/h) are used as risk targets when walking near the outside line of the roadway (hereafter, walking position Inside) and when walking on the outside of the road 0.5m from the roadway outside line (hereafter, walking position 0utside). Regarding the vehicle speed, the speed (initial speed) until the risk target starts to be seen is set to 30km/h, 40km/h, 50km/h, or 60km/h, and the vehicle is set to be in the center of the lane. In the 140 m distance from when the risk target starts to appear until the risk target is overtaken, the vehicle speed and lateral position can be changed by the driver's braking operation and steering wheel operation. In addition, if there is no oncoming vehicle on the oncoming lane side of the road, and if the risk target and the oncoming vehicle are almost at the same position if the vehicle is driven at the initial speed (hereinafter referred to as oncoming vehicle - near), the initial speed will be maintained. When the vehicle comes next to the risk target, the oncoming vehicle is still 40 to 60m ahead (hereafter referred to as oncoming vehicle - far). There were 18 subjects.

In the above simulated driving experiment, the start timing of each of the braking operation and the steering wheel steering to avoid the risk object (see Fig. 2 (A)), the minimum speed during the side passage of the risk object (Fig. 2 Vmin in (B)), lateral distance when the risk target passes sideways (GAP in FIG. 2B), position of the oncoming vehicle when the risk target passes sideways (only when there is an oncoming vehicle) was detected. Regarding the operation to avoid the risk target, the braking operation is started when the brake pedal opening reaches 5%, and the steering wheel is turned to the right to avoid the risk target. and the trajectory is displaced to the right. The start timing of the operation to avoid the risk object was measured by TTC (the length of time between the start of the avoidance action and the time when the vehicle is expected to reach the side of the risk object) ( See FIG. 2(A)). TTC is calculated by Δ/Vini from the distance Δ to the risk target at the start of the avoidance action and the vehicle speed Vini.

Various analyzes were conducted on the results, and the starting time (TTC), the starting time (TTC), The minimum speed (Vmin) when passing the risk target sideways and the average value of the lateral distance (GAP) when passing the risk target sideways, respectively, depending on whether or not two or more of the following conditions are satisfied, the driver were classified into driving types, it was found that the tendency of each driving type can be grasped.
・Condition 1: Do you take evasive action early (TTC ≥ 4 seconds)?
・Condition 2: Sufficient deceleration (Vmin≤30km/h)
・Condition 3: Do you keep a distance from pedestrians (GAP > 1.5m)?
Thus, when the number of conditions 1 to 3 that are satisfied is 0 or 1, driving type A (first type) is used, and if the number of conditions 1 to 3 that are satisfied is 2 or 3, driving type B is used. (Second type), and the results of analysis of driving tendencies will be explained for each.

(About prioritized operations)
Referring to FIG. 3(A), first, looking at the start timing (TTC) of the avoidance action of the risk object by driving type, as shown in the figure, for both driving types A and B, those who are early start operating from TTC = 10 seconds. Many subjects started the operation at a TTC of 4 to 6 seconds for the driving type B and at a TTC of 3 to 5 seconds for the driving type A. Next, referring to FIG. 3(B), in terms of the ratio of operations executed when avoiding risk targets by driving type and road type, road type A is steering only (51 %) and no operation (41%). Driving type B mainly uses both braking and steering (51%) and only steering (33%). In Type A, the ratio of using braking increases, but only steering is dominant (54%), while in Driving Type B, both braking and steering (68%) increase significantly. In addition, in road type B, among the subjects who used both braking and steering, the percentage of subjects who performed the braking operation before steering the steering wheel was 70% in driving type A. For type B, it was 92%. From this, while driving type A mainly avoids steering by steering, driving type B mainly avoids by braking, and driving type B starts avoiding action earlier than driving type A. It is understood that Therefore, in the driving assistance, in the case of driving type A, steering assistance is provided first, and in the case of driving type B, braking operation assistance is provided first, Moreover, it was suggested that by starting the assistance earlier in the case of driving type B than in the case of driving type A, it is possible to more effectively adapt the driving assistance to the tendency of each driving type.

(Differences depending on the type of risk target)
With reference to FIG. 4(A), the side distance GAP at the time of side passage of the risk object for each type of risk object for each driving type (road type B, initial speed 40 km / h, no oncoming vehicle , walking position Inside), driving type B was significantly greater than driving type A. In addition, when looking at the types of risk targets, there was almost no difference depending on the type of risk targets in the case of driving type B, but in the case of driving type A, there was a difference depending on the type of risk targets. . This suggests that driving type A responds more sensitively to the type of risk object. Therefore, in driving support, in the case of driving type A, the target value of the side distance GAP is set to be variably adapted according to the type of risk target, and in the case of driving type B, In this case, regardless of the type of risk target, setting the target value of the lateral distance GAP to be longer than that of driving type A suggests that driving assistance can be more effectively adapted to the tendency of each driving type. .

(differences depending on the type of road)
With reference to FIG. 4(B), the minimum speed Vmin (in the case where the initial speed is 40 km/h or 50 km/h and there is no oncoming vehicle) for each driving type and road type when passing the side of the risk target is Looking at it, regardless of the road type, driving type B has a lower minimum speed Vmin than driving type A. In the case of driving type A, there is almost no difference in minimum speed Vmin depending on the road type, and In the case of driving type B, it was found that road type B, which has a narrower road width than road type A, has a significantly lower minimum speed. Therefore, in driving support, in the case of driving type A, the minimum speed target value is set so that the vehicle passes the side of the risk target at an appropriate speed regardless of the type of road. In the case of driving type B, by setting the minimum speed target value variably according to the type of road (for example, the narrower the road width, the lower the minimum speed target value is set) , suggesting that the driving assistance can be more effectively adapted to the tendency of each driving type.

(Difference due to presence of oncoming vehicle)
FIG. 5(A) shows the frequency distribution of the positions of oncoming vehicles when the vehicle passes the side of the risk target under oncoming vehicle-near conditions for each driving type and road type. B) shows the frequency distribution of the position of the oncoming vehicle when the vehicle passes the side of the risk target under the oncoming vehicle - far condition on road type B for each driving type. Referring to the same figure, first, for driving type A, under both conditions of oncoming vehicle - close and oncoming vehicle - far, regardless of the road type, without waiting for the oncoming vehicle to pass each other, the side of the risk target It is understood that there is a tendency to pass through On the other hand, regarding driving type B, it is understood that there is a tendency to pass on the side of the risk target after passing the oncoming vehicle regardless of the road type under both oncoming vehicle - near and oncoming vehicle - far conditions. be. Therefore, in each of the driving type A and the driving type B, it is understood that there is almost no difference in evasive behavior depending on the position of the oncoming vehicle, although the timing of passing the risk object on the side is different from each other. From the results of experiments so far, it has been suggested that driving assistance that mainly focuses on steering in driving type A and braking in driving type B is effective. Since it is possible to cope with the difference in avoidance behavior against oncoming vehicles in each of driving type B Since braking is the main function, it is expected that the vehicle will be decelerated by driving assistance and that the oncoming vehicle will pass before the risk target passes sideways.) It was suggested that it is not necessary to change the mode of driving support due to the presence of a car (when performing more precise driving support, the mode of driving support may be changed due to the presence of an oncoming vehicle. , it should be understood that such cases are also within the scope of the present invention.).

(3) Apparatus Operation (i) Discrimination of Driving Type As described above, in the apparatus of the present embodiment, different types of driving assistance are provided depending on the driving type of the driver. Prior to driving the vehicle, a determination of the driver's driving type is made. As already mentioned, such a determination can be made by using a simulated driving device such as a driving simulator, or by actually driving a vehicle, as in the case of the above experiment, when the driver detects that there is a risk target on the side of the road. Measure the start time (TTC), the minimum speed (Vmin) when the risk target passes sideways, and the lateral distance (GAP) when the risk target passes sideways when an avoidance maneuver is performed in a situation where , and whether or not the measured values satisfy the conditions 1 to 3 above, respectively, and the driving type may be determined according to the result. In particular, in the case of discriminating the driving type using values detected in actual running, in order to suppress variation in discrimination, when a specific running state is established, for example,
(a) Straight road section without median line (road width about 3m to 5m),
(b) initial speed (running speed before risk encounter) (approximately 40 km/h to 50 km/h);
(c) there are no oncoming vehicles;
It is preferable to use the value detected when the condition is satisfied. In one aspect of the present embodiment, the driving type may be distinguished into the driving type A and the driving type B as in the above experiment, but the driving type may be further subdivided. good. In addition, in the above conditions, the set predetermined value may be appropriately set to another value by adaptation. Furthermore, parameters selected as conditions and respective thresholds may be used regardless of the above experimental examples, and it is understood that such cases also belong to the scope of the present invention. should.

Although not shown, in order to discriminate the driving type, the device includes means for collecting and recording data during driving when approaching the risk target, means for selecting data for discriminating the driving type, Means for determining driving type may be provided so that timely data collection and driving type determination are performed while the vehicle is running.

(ii) Device processing process Referring to FIG. 6, in one form of the driving assistance device according to the present embodiment, generally speaking, the acquisition of driving type information (step 1), driving according to the driving type Setting of support start time (steps 2-6), detection of risk target status and road conditions when risk target is detected (steps 7-8), setting of driving support mode according to driving type (steps 9- 13), execution of driving assistance (steps 14 to 18) is executed. The processing of FIG. 6 may be repeatedly executed in a predetermined processing cycle determined according to the processing speed of the device when driving assistance is requested.

Specifically, in the processing, first, the driver's driving type information, which has been determined as described above, is referred to (step 1). Then, the start timing of driving support is set according to the driving type (steps 2 to 6). Here, the start timing of driving assistance may be set by the TTC up to the risk target when the risk target is detected. In addition, depending on the driving type, the timing for starting the braking operation and the timing for starting the steering may differ. , and the start timing of driving assistance for steering (steering assistance start timing) Ts_S may be set separately. Specifically, for example, when the driving type is determined in the same manner as in the above experiment, in the case of driving type A (step 2), the braking support start time Tb_S and the steering support start time Ts_S are set in advance. When the values Tb_S←Tb_A and Ts_S←Ts_A are set appropriately determined by experiments or the like (step 4), it is known from the results of the above experiments that it is preferable to precede driving assistance with respect to steering. Therefore, Ts_A>Tb_A is set. In the case of driving type B (step 3), the braking support start time Tb_S and the steering support start time Ts_S are set to values Tb_S←Tb_B and Ts_S←Ts_B, which are appropriately determined in advance by experiments or the like. On the other hand (step 5), since it is known from the results of the above experiment that it is preferable to precede the braking operation with driving assistance, Tb_B>Ts_B is set. Here, from the results shown in FIG. 3A, since driving type B tends to start the avoidance action earlier than driving type A, braking support start timing Tb_S (=Tb_B) for driving type B is , the steering assistance start timing Ts_S (=Ts_A) of the driving type A may be set larger. When the driving type is unknown (U), values Tb_S.rarw.Tb_U and Ts_S.rarw.Ts_U appropriately determined by experiments or the like may be set (step 6).

Then, while the vehicle is running, the presence or absence of a risk target on the side of the road is monitored. , and the type of road (road width, presence/absence of a median line, etc.) are detected (step 8). Then, according to the driving type, the driving assistance to be provided is set in a manner suitable for the driving tendency. Specifically, for example, when the driving type is determined in the same manner as in the above experiment, in the case of driving type A (step 9), as shown in FIG. The lateral distance GAP changes sensitively with respect to the type of road, and as shown in FIG. The target value of the side distance GAP when passing the risk object sideways is set variably according to the type of the risk object (for example, the target value of the side distance GAP may be set larger in the order of adults, bicycles, and children). ), the target value of the minimum vehicle speed Vmin when passing through the side of the risk object for assisting the braking operation may be set to an appropriately determined value regardless of the road type (step 11). In the case of driving type B (step 10), as shown in FIG. , the minimum vehicle speed Vmin changes sensitively with respect to the type of road. The target value of the minimum vehicle speed Vmin at risk target side passage for assisting the braking operation may be variably set according to the road type (for example, road The narrower the width, the smaller the target value of the minimum vehicle speed Vmin is set, and when there is no median line, the target value of the minimum vehicle speed Vmin may be set smaller than when there is a median line (step 12). Here, according to the tendency shown in the results of FIG. may be set larger than any of the target values of the lateral distance GAP for driving type A. According to the tendency shown in the results of FIG. However, since the minimum vehicle speed Vmin is set lower than that for the driving type A, any of the target values for the minimum vehicle speed Vmin for the driving type B may be set lower than the minimum vehicle speed Vmin for the driving type A. Note that the driving type is unknown. In case (U), the target value of the lateral distance GAP and the target value of the minimum vehicle speed Vmin may be set to appropriately determined values (step 13). It may be determined by fit through, etc.

Thus, when the vehicle approaches the risk target and TTC falls below the braking support start time Tb_S (step 14), braking operation support is executed (step 15), and when TTC falls below the steering support start time Ts_S (step 16), assistance for steering is executed (step 17). In the case of driving type A, since Ts_A>Tb_A is set to Ts_S>Tb_S, assistance for steering is started first. On the other hand, in the case of driving type B, since Ts_B<Tb_B is set to Ts_S<Tb_S, the assistance for the braking operation is started first. When the driving type is unknown (U), the assistance corresponding to the longer one of the braking assistance start timing Tb_S and the steering assistance start timing Ts_S is executed first.

Specifically, when the vehicle passes the side of the risk target, the side distance GAP is set to the target value set above. The display may guide the driver to steer, the steering torque may be adjusted so as to make it easier to turn the steering wheel in the target steering direction, or automatic steering control may be executed. Steering guidance, steering angle or yaw rate control to achieve a lateral distance GAP target value is based on the immediate relative position or even relative velocity of the risk object, steering angle sensor readings, yaw rate readings, etc. It may be achieved by any method. Specifically, in assisting the braking operation, audio or visual indication is provided through the HMI device so that the minimum vehicle speed Vmin when the vehicle passes the side of the risk target becomes the target value set above. may prompt the driver to brake, adjust the reaction forces of the accelerator and brake pedals to facilitate deceleration, or perform automatic braking control. Induction of braking, deceleration or vehicle speed control to achieve the target value of the minimum vehicle speed Vmin depends on the immediate relative position or further relative speed of the risk object, the detection value of the acceleration/deceleration sensor and the vehicle speed value (from the wheel speed value may be calculated as appropriate.), etc., and may be achieved by any method.

The driving assistance described above ends after the vehicle has passed the side of the risk object, and the above process is executed each time the next risk object is detected (step 7).

As described with reference to FIG. 5, based on the results of the above experiment, the processing of this embodiment is executed in the same way regardless of whether or not there is an oncoming vehicle when the risk target is detected. may be configured. This is advantageous in that the configuration of the control for driving assistance does not become complicated. However, in order to set the mode of driving assistance more precisely, the mode of driving assistance may be subdivided and set according to the presence or absence and position of an oncoming vehicle.

The start timing of the avoidance action of the risk object in the above configuration may be measured by the distance (Δ in FIG. 2A) from the vehicle to the risk object instead of the TTC. should be understood to fall within the scope of

Thus, according to the configuration of the present embodiment described above, it is possible to change the strength of the driving assistance in accordance with the driving tendency of the driver. This makes it possible to reduce the driver's annoyance with the driving assistance, thereby reducing the possibility of stopping the driving assistance.

Although the above description has been made with respect to the embodiments of the present invention, many modifications and changes can be easily made by those skilled in the art, and the present invention is limited only to the above-exemplified embodiments. It will be clear that the invention is non-limiting and can be applied to a variety of devices without departing from the concept of the invention.

Claims (1)

A driving support device for a vehicle,
a driving type information acquisition means for acquiring driving type information of the driver determined in advance based on characteristics of the driver of the vehicle during driving for risk object avoidance;
risk object detection means for detecting a risk object on the side of the road in the traveling direction of the vehicle;
When the risk target is detected, the driving support mode determination means determines a driving support mode for avoiding the risk target, and provides different modes of driving support according to the acquired driving type of the driver. means for deciding to provide;
and driving assistance executing means for executing the determined driving assistance mode.

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