JP3772813B2 - VEHICLE DRIVE OPERATION ASSISTANCE DEVICE, VEHICLE DRIVE OPERATION ASSISTANCE METHOD, AND VEHICLE USING THE METHOD - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving operation assistance device for a vehicle that assists a driver's operation.
[0002]
[Prior art]
Conventional vehicle driving assistance devices detect the situation (obstacles) around the vehicle and determine the potential risk potential at that time (see, for example, Patent Document 1). This vehicle driving operation assisting device controls the steering assist torque based on the calculated degree of risk, thereby suppressing a steering operation that tends to cause an unexpected situation.
Prior art documents related to the present invention include the following.
[Patent Document 1]
Japanese Patent Application Laid-Open No. 10-211886
[Patent Document 2]
Japanese Patent Laid-Open No. 10-166889
[Patent Document 3]
Japanese Patent Laid-Open No. 10-166890
[0003]
[Problems to be solved by the invention]
However, the above-described vehicle driving operation assisting device promotes prohibition of operation in a specific inappropriate situation, and in a complicated situation where both steering and acceleration / deceleration operations are required, driving is performed. It was difficult to prompt the operation in the appropriate direction.
[0004]
[Means for Solving the Problems]
The vehicle driving assistance device according to the present invention calculates an obstacle detection means for detecting an obstacle existing around the own vehicle and a risk potential for the obstacle of the own vehicle based on a signal from the obstacle detection means. A risk potential calculating means that controls the operation of the vehicle equipment so as to prompt the driver to perform driving operations related to the forward and backward movements and the left and right movements of the host vehicle based on the signal from the risk potential calculation means; The ratio of the driving operation assistance in the front-rear direction and the driving operation assistance in the left-right direction with respect to the driver is corrected according to the running condition detection means for detecting the running condition of the host vehicle and the running condition detected by the running condition detection means. Operation auxiliary correction means, The traveling state detecting means detects the host vehicle speed as the traveling state, and the operation assist correcting means is when the own vehicle speed detected by the traveling state detecting means is greater than or equal to a predetermined value, compared to when the own vehicle speed is less than the predetermined value. Correction to increase the ratio of driving assistance in the front-rear direction To do.
[0005]
According to the driving state of the host vehicle, the ratio of the operation assistance in the front-rear direction and the left-right direction for the driver is corrected, and the operation instructions from important directions are corrected. . In particular, when the vehicle speed is equal to or higher than a predetermined value, the ratio of driving assistance in the front-rear direction is corrected to be larger than when the vehicle speed is lower than the predetermined value Therefore, more important information can be communicated to the driver in an easy-to-understand manner, and driving operations can be assisted appropriately.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
<< First Embodiment >>
A vehicle operation assistance device according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a system diagram showing a configuration of a vehicular driving assist device 1 according to a first embodiment of the present invention. FIG. 2 is equipped with a vehicular driving assist device 1 for a vehicle according to the present invention. It is a block diagram of the vehicle to which a driving operation assistance method is applied.
[0007]
First, the configuration of the vehicle driving assistance device 1 will be described. The laser radar 10 is attached to a front grill part or a bumper part of the vehicle and scans infrared light pulses in the horizontal direction. The laser radar 10 measures the reflected wave of the infrared light pulse reflected by a plurality of reflectors in front (usually the rear end of the front vehicle), and determines the distance between the plurality of front vehicles from the arrival time of the reflected wave. Detect the distance and its direction. The detected inter-vehicle distance and presence direction are output to the controller 50. In the present embodiment, the presence direction of the front object can be expressed as a relative angle with respect to the host vehicle. The forward area scanned by the laser radar 10 is about ± 6 deg with respect to the front of the host vehicle, and a forward object existing within this range is detected. The laser radar 10 detects not only the inter-vehicle distance to the vehicle ahead and the direction in which it is present, but also the relative distance to the obstacle such as a pedestrian existing in front of the host vehicle and the direction in which it exists.
[0008]
The front camera 20 is a small CCD camera, a CMOS camera, or the like attached to the upper part of the front window, detects the state of the front road as an image, and outputs it to the controller 50. The detection area by the front camera 20 is about ± 30 deg in the horizontal direction, and the front road scenery included in this area is captured as an image.
[0009]
The rear side camera 21 is two small CCD cameras or CMOS cameras mounted near the left and right ends of the upper part of the rear window. The rear side camera 21 detects the road behind the host vehicle, in particular, the situation on the adjacent lane as an image, and outputs it to the controller 50.
[0010]
The vehicle speed sensor 30 detects the traveling vehicle speed of the host vehicle from the number of rotations of the wheels and outputs it to the controller 50.
[0011]
The controller 50 controls the vehicle driving operation assisting device 1 as a whole. The controller 50 uses the vehicle speed input from the vehicle speed sensor 30, the distance information input from the laser radar 10, and the vehicle periphery image information input from the front camera 20 and the rear side camera 21 to Detect obstacle status. The controller 50 detects an obstacle situation around the host vehicle by performing image processing on image information input from the front camera 20 and the rear side camera 21. Here, the obstacle situation around the host vehicle includes the inter-vehicle distance to the other vehicle traveling in front of the host vehicle, the presence and degree of approach of the other vehicle approaching the adjacent lane from the rear of the host vehicle, and the lane identification line (white line). The left and right positions of the vehicle, that is, the relative position and angle, and the shape of the lane identification line. Also, pedestrians and motorcycles that cross the front of the vehicle are detected as obstacles.
[0012]
The controller 50 calculates the risk potential of the host vehicle for each obstacle based on the detected obstacle situation. Further, the controller 50 calculates the total risk potential around the host vehicle by combining the risk potentials for the respective obstacles, and performs control according to the risk potential as will be described later.
[0013]
The steering reaction force control device 60 is incorporated in the steering system of the vehicle, and controls the torque generated by the servo motor 61 in response to a command from the controller 50. The servo motor 61 controls the torque generated according to the command value from the steering reaction force control device 60, and can arbitrarily control the steering reaction force generated when the driver operates the steering wheel.
[0014]
The accelerator pedal reaction force control device 80 controls the torque generated by the servo motor 81 incorporated in the link mechanism of the accelerator pedal 82 in response to a command from the controller 50. The servo motor 81 controls the reaction force generated according to the command value from the accelerator pedal operation reaction force control device 80, and can arbitrarily control the pedal force generated when the driver operates the accelerator pedal 82. .
[0015]
The brake pedal reaction force control device 90 controls the brake assist force generated by the brake booster 91 in response to a command from the controller 50. The brake booster 91 controls the brake assist force generated according to the command value from the brake pedal reaction force control device 90, and can arbitrarily control the pedaling force generated when the driver operates the brake pedal 92. . As the brake assist force increases, the brake pedal operation reaction force decreases, and the brake pedal 92 is easily depressed.
[0016]
Next, the operation of the vehicle driving assistance device 1 according to the first embodiment will be described. The outline of the operation will be described below.
The controller 50 determines the traveling vehicle speed of the host vehicle, the relative position between the host vehicle and other vehicles existing in the front or rear side of the host vehicle, the moving direction thereof, the relative position of the host vehicle with respect to the lane identification line (white line), and the like. Recognize obstacles around your vehicle. The controller 50 obtains the risk potential of the own vehicle for each obstacle based on the recognized obstacle situation. The controller 50 further calculates the reaction force control amount in the front-rear direction and the reaction force control amount in the left-right direction by adding the risk potential for each obstacle for each component in the front-rear direction and the left-right direction.
[0017]
The calculated reaction force control amount in the front-rear direction is output to the accelerator pedal reaction force control device 80 and the brake pedal reaction force control device 90 as a reaction force control command value in the front-rear direction. The accelerator pedal reaction force control device 80 and the brake pedal reaction force control device 90 control the accelerator pedal reaction force characteristic and the brake by controlling the servo motor 81 and the brake booster 91 according to the input reaction force control command values. Change the pedal reaction force characteristics. By changing the accelerator pedal / brake pedal reaction force characteristics, the actual accelerator pedal operation amount and brake pedal operation amount of the driver are controlled to be promoted to appropriate values.
[0018]
On the other hand, the calculated reaction force control amount in the left-right direction is output to the steering reaction force control device 60 as a reaction force control command value in the left-right direction. The steering reaction force control device 60 changes the steering reaction force characteristic by controlling the servo motor 61 in accordance with the input control reaction force command value. By changing the steering reaction force characteristic, control is performed so as to promote the actual steering angle of the driver to an appropriate steering angle.
[0019]
As described above, the vehicle driving operation assistance device 1 according to the first embodiment controls the reaction force generated when the accelerator pedal / brake pedal is depressed or the steering wheel is operated according to the risk potential. It assists the driver's acceleration / deceleration operation and steering operation of the host vehicle, and assists the driver's driving operation appropriately. However, when the reaction force in the vehicle front-rear direction and the left-right direction is controlled in the same manner, it may be difficult for the driver to know from which direction the information is more important.
[0020]
For example, when the host vehicle approaches the corner by traveling alone, the operational reaction forces in the front-rear direction and the left-right direction are controlled according to the approaching state to the corner. When the vehicle is relatively far from the corner, the risk potential in the front-rear direction is mainly transmitted to the driver as the operating reaction force of the accelerator pedal and brake pedal, and as the vehicle approaches the corner, the risk potential in the left-right direction is gradually driven as the steering reaction force. Communicated to the person. After the vehicle enters the corner, the risk potential in the left / right direction is mainly transmitted to the driver.
[0021]
On the other hand, when the host vehicle follows the preceding vehicle and approaches the corner, before entering the corner, mainly the risk potential in the front-rear direction is transmitted as a pedal reaction force according to the degree of approach with the preceding vehicle. If the vehicle enters the corner while following the preceding vehicle, a risk potential related to the corner is generated in addition to the forward and backward risk potential of the preceding vehicle. Therefore, it is difficult to determine whether the forward / backward risk potential transmitted as the pedal reaction force is due to the preceding vehicle or the corner. In this state, since the risk potential due to the preceding vehicle is the most important information, the driver tends to consider that all the risk potential at this point is due to the preceding vehicle. Therefore, if the risk potential in the left-right direction is transmitted as the steering reaction force after entering the corner, it becomes difficult for the driver to understand what the steering reaction force is due to.
[0022]
Therefore, in the first embodiment of the present invention, the ratio of the front / rear / left / right ratio of the risk potential distribution around the vehicle is modified (deformed) according to the driving state, so that particularly important information can be easily understood. To experience.
[0023]
Hereinafter, how the reaction force characteristic command value, that is, the reaction force control command value is determined in the first embodiment will be described with reference to FIG. FIG. 3 is a flowchart showing a processing procedure of the driving operation assistance control processing in the controller 50 according to the first embodiment. This processing content is continuously performed at regular intervals, for example, every 50 msec.
[0024]
-Processing flow of controller 50 (Fig. 3)-
First, the travel state is read in step S101. Here, the traveling state is information relating to the traveling state of the host vehicle including the obstacle state around the host vehicle. Specifically, the relative distance and relative angle to the forward vehicle detected by the laser radar 10 and the relative position of the white line relative to the host vehicle based on the image input from the front camera 20 (that is, the displacement and relative angle in the left-right direction). ), The shape of the white line and the relative distance and relative angle to the forward traveling vehicle are read, and further the relative distance and relative angle to the traveling vehicle existing behind the adjacent lane based on the image input from the rear side camera 21 are read. Furthermore, the host vehicle speed detected by the vehicle speed sensor 30 is read. Further, based on the images detected by the front camera 20 and the rear side camera 21, the type of obstacle existing around the vehicle, that is, whether the obstacle is a four-wheeled vehicle, a two-wheeled vehicle, a pedestrian, or the like. recognize.
[0025]
In step S102, the current vehicle surroundings are recognized based on the driving state data read and recognized in step S101. Here, the relative position, the moving direction and the moving speed of each obstacle with respect to the host vehicle detected before the previous processing cycle and stored in a memory (not shown), and the current running state data obtained in step S101 Thus, the current relative position of each obstacle to the host vehicle, the moving direction and the moving speed thereof are recognized. Then, it recognizes how other vehicles or white lines that are obstacles to the traveling of the host vehicle are arranged around the host vehicle and how they move relatively.
[0026]
In step S103, a margin time TTC (Time To Collision) for each recognized obstacle is calculated for each obstacle. The margin time TTCk for the obstacle k is obtained by the following (Equation 1).
[Expression 1]
TTCk = (Dk−σ (Dk)) / (Vrk + σ (Vrk)) (Formula 1)
Here, Dk: relative distance from the host vehicle to the obstacle k, Vrk: relative speed of the obstacle k with respect to the host vehicle, σ (Dk): variation in relative distance, σ (Vrk): variation in relative speed, respectively Show.
[0027]
Relative distance and relative speed variations σ (Dk), σ (Vrk) are sensors that recognize an obstacle k in consideration of the degree of influence when an uncertain state of the detector or an unexpected situation occurs. And the type of the recognized obstacle k.
[0028]
The laser radar 10 is a correct distance regardless of the detection distance, that is, the relative distance between the host vehicle and the obstacle, as compared with the detection of an obstacle by the front camera 20 or the rear side camera 21 using a camera such as a CCD. Can be detected. Therefore, for example, as shown in FIG. 4A, when the relative distance Dk to the obstacle k is detected by the laser radar 10, the variation σ (Dk) is set to a substantially constant value regardless of the relative distance Dk. To do. On the other hand, when the relative distance Dk is detected by the cameras 20 and 21, the variation σ (Dk) is set to increase exponentially as the relative distance Dk increases. However, when the relative distance Dk of the obstacle k is small, the relative distance can be detected more accurately by the camera than when the relative distance Dk is detected by the laser radar. Set to a smaller value.
[0029]
For example, when the relative distance Dk is detected by the laser radar 10, the variation σ (Vrk) of the relative speed Vrk is set so as to increase in proportion to the relative speed Vrk as shown in FIG. On the other hand, when the relative distance Dk is detected by the cameras 20 and 21, the relative speed variation σ (Vrk) is set to increase exponentially as the relative speed Vrk increases. FIGS. 4A and 4B show an example in which the detected obstacle is a four-wheeled vehicle.
[0030]
When an obstacle situation is detected by the front camera 20 and the rear side camera 21, the type of the obstacle can be recognized by performing image processing on the detected image. Therefore, as shown in FIGS. 5A and 5B, when the obstacle status is detected by the cameras 20 and 21, the relative distance and the relative speed variation σ (Dk) according to the type of the recognized obstacle. ), Σ (Vrk). FIGS. 5A and 5B show variations σ (Dk) and σ (Vrk) when a four-wheeled vehicle, a two-wheeled vehicle, a pedestrian, and a lane marker (white line) are detected as the obstacle k, respectively. Yes.
[0031]
The relative distance Dk is detected by the cameras 20 and 21 because the detection accuracy is higher as the size of the obstacle k is larger. For example, as shown in FIG. The distance variation σ (Dk) is set smaller than the variation σ (Dk) in the case of a two-wheeled vehicle or a pedestrian. On the other hand, the relative speed variation σ (Vrk) is set so that the variation σ (Vrk) increases as the moving speed assumed for each obstacle k increases, as shown in FIG. 5B, for example. That is, since the moving speed of the four-wheeled vehicle is assumed to be higher than the moving speed of the two-wheeled vehicle or the pedestrian, the variation σ (Vrk) when the obstacle k is a four-wheeled vehicle when the relative speed Vrk is the same. It is set larger than the variation σ (Vrk) in the case of a two-wheeled vehicle or a pedestrian. As shown in FIGS. 5A and 5B, the relative distance and relative speed variation σ (Dk) and σ (Vrk) with respect to the lane marker are the relative distance and relative speed variation σ ( Dk) is set smaller than σ (Vrk).
[0032]
When the obstacle k is detected by both the laser radar 10 and the camera 20, for example, the margin time TTCk for the obstacle k is calculated using the larger variations σ (Dk) and σ (Vrk). can do.
[0033]
In step S104, the risk potential RPk for each obstacle k is calculated using the margin time TTCk calculated in step S103. Here, the risk potential RPk for each obstacle k is obtained by the following (Equation 2).
[Expression 2]
RPk = (1 / TTCk) × wk (Formula 2)
Here, wk: indicates the weight of the obstacle k. As shown in (Expression 2), the risk potential RPk is expressed as a function of the allowance time TTCk using the reciprocal of the allowance time TTCk. The larger the risk potential RPk, the greater the degree of approach to the obstacle k. Show.
[0034]
The weight wk for each obstacle k is set according to the type of the detected obstacle. For example, when the obstacle k is a four-wheeled vehicle, a two-wheeled vehicle, or a pedestrian, the weight wk = 1 is set because the importance, that is, the degree of influence when the own vehicle approaches the obstacle k is high. On the other hand, when the obstacle k is a lane marker, the importance when the host vehicle approaches or comes in contact is relatively smaller than other obstacles, so the weight wk is set to about 0.5, for example. Also, even when the same lane marker has an adjacent lane beyond the lane marker, and when there is no lane beyond the lane marker and only a guardrail is present, the weight at the time of proximity of the host vehicle differs, so the weight wk is different. It can also be set as follows.
[0035]
The lane marker is distributed in a certain range of existing directions, rather than being determined in one direction. Therefore, the lane markers around the own vehicle detected by the cameras 20 and 21 are divided into minute angles based on the own vehicle, and the respective risk potentials are calculated from the relative positions of the lane markers for the minute angles. Further, the risk potential RPlane is calculated by integrating the risk potential for a minute angle in the existence direction range. That is, the risk potential RPlane for the lane marker is expressed by the following (Equation 3).
[Equation 3]
RPlane = ∫ ((1 / TTClane) × wlane) dL (Formula 3)
[0036]
In step S105, components in the vehicle front-rear direction are extracted from the risk potential RPk for each obstacle k calculated in step S104 and added to calculate a total front-rear risk potential for all obstacles existing around the vehicle. . The front-rear risk potential RPlongitudinal is calculated by the following (formula 4). The risk potential RPk for each obstacle k includes the risk potential RPlane for the lane marker.
[Expression 4]
RPlongitudinal = Σ _k (RPk × cos θk) (Formula 4)
Here, θk: indicates the direction in which the obstacle k exists with respect to the host vehicle, and when the obstacle k exists in the front direction of the vehicle, that is, in front of the host vehicle, θk = 0 and the obstacle k exists in the rear direction of the vehicle , Θk = 180.
[0037]
In the subsequent step S106, components in the left-right direction of the vehicle are extracted from the risk potential RPk for each obstacle k calculated in step S104 and added to calculate a comprehensive left-right risk potential for all obstacles existing around the vehicle. To do. The left-right risk potential RPlateral is calculated by the following (Formula 5).
[Equation 5]
RPlateral = Σ _k (RPk × sin θk) (Formula 5)
[0038]
In step S107, based on the running state data read in step S101, it is determined how to correct the front-rear direction reaction force control amount and the left-right direction reaction force control amount according to the current running state. Here, as shown in FIG. 6, the current traveling state is determined under the following three conditions, and the reaction force control amount correction method is determined. (1) Conditions for correcting so that operation assistance in the longitudinal direction of the vehicle is increased.
When the traveling vehicle speed of the host vehicle is a predetermined vehicle speed, for example, 70 km / h or more.
(2) Conditions for correcting the operation assistance in the left-right direction of the vehicle to be large.
When the vehicle is traveling in the city.
(3) Conditions for correction so that the absolute value of the risk potential RP increases.
a. When the driver is fatigued.
b. When the driving environment of your vehicle is bad. For example, during bad weather such as rain or fog, or when driving at night.
[0039]
The condition (2) can be determined according to, for example, map information by the navigation system or the vehicle speed. When determining based on the own vehicle speed, if the own vehicle speed is traveling at a predetermined vehicle speed, for example, 40 km / h or less, it is determined that the vehicle is traveling in an urban area. The fatigue state of the driver in the condition (3a) can be determined based on, for example, continuous running time. Specifically, when the time from when the ignition switch is turned on until it is turned off is a predetermined time, for example, 2 hours or more, the driver can be determined to be in a fatigued state. For example, the driving environment in the condition (3b) determines whether or not it is raining based on the wiper operation state, and determines whether or not fog is generated based on the lighting state of the fog lamp. For example, it is determined whether it is nighttime based on the lighting state of the headlamp.
[0040]
When the absolute value of the risk potential RP is increased, the absolute values of both the front-rear direction risk potential RPlongitudinal and the left-right direction risk potential RPlateral are increased, and both the front-rear direction and left-right operation assistance are increased.
[0041]
The calculation of the front-rear direction reaction force control amount and the left-right direction reaction force control amount is performed in subsequent steps S108 and S109, respectively, but gains for correcting each reaction force control amount are set according to the running state. Keep it.
[0042]
When the current traveling state is applicable to the condition (1), the longitudinal gain Glongitudinal is corrected so as to increase, for example, Glongitudinal = 1.5 is set, and the operational reaction force control amount in the longitudinal direction is corrected. When the current traveling condition is applied to the condition (2), the lateral gain Glateral is corrected so as to increase, for example, Glateral = 1.5 is set, and the lateral reaction force control amount is corrected. When the current running condition is applicable to the condition (3), the longitudinal gain Glongitudinal and the lateral gain Glateral are corrected so as to increase, for example, Glongitudinal = 1.5, Glateral = 1.5, and the longitudinal direction And the operation reaction force control amount in the horizontal direction is corrected. When the current running state does not apply to any of the conditions (1) to (3) (normal state), the front / rear direction gain Glongitudinal = 1 and the left / right direction gain Glateral = 1 are set, and the reaction force control is performed. The amount is not corrected.
[0043]
In step S108, from the longitudinal risk potential RPlongitudinal calculated in step S105, the longitudinal control command value, that is, the reaction force control command value FA output to the accelerator pedal reaction force control device 80 and the brake pedal reaction force control device 90 are output. The reaction force control command value FB to be calculated is calculated. In accordance with the forward / backward risk potential RPlongitudinal, the greater the risk potential, the greater the risk potential, the control reaction force is generated in the direction to return the accelerator pedal 82 and the brake pedal 92 is controlled in the direction in which the brake pedal 92 is more easily depressed. Generate reaction force. Thus, the driver's operation is prompted from the accelerator pedal operation to the brake pedal operation.
[0044]
FIG. 7 shows the relationship between the longitudinal risk potential RPlongitudinal and the accelerator pedal reaction force control command value FA. As shown in FIG. 7, when the longitudinal risk potential RPlongitudinal is smaller than a predetermined value RPmax, the accelerator pedal reaction force control command value FA is calculated so as to generate a larger accelerator pedal reaction force as the longitudinal risk potential RPlongitudinal is larger. To do. When the front-rear risk potential RPlongitudinal is equal to or greater than a predetermined value RPmax, the accelerator pedal reaction force control command value FA is fixed to the maximum value FAmax so as to generate the maximum accelerator pedal reaction force.
[0045]
FIG. 8 shows the relationship between the longitudinal risk potential RPlongitudinal and the brake pedal reaction force control command value FB. As shown in FIG. 8, when the front-rear risk potential RPlongitudinal is equal to or greater than a predetermined value RPmax, the brake pedal reaction force control is performed so that the smaller the front-rear risk potential RPlongitudinal, the smaller the brake pedal reaction force, that is, the greater the brake assist force. Command value FB is calculated. When the longitudinal risk potential RPlongitudinal becomes larger than the predetermined value RP1, the reaction force control command value FB is fixed to FBmin so as to generate the minimum brake pedal reaction force. When the longitudinal risk potential RPlongitudinal is smaller than the predetermined value RPmax, the brake pedal reaction force control command value FB is set to zero, and the brake pedal reaction force characteristic is not changed.
[0046]
Further, a predetermined longitudinal gain Glongitudinal is added to the calculated longitudinal reaction force command values FA and FB to obtain an actual reaction force command value. When the current traveling state is applicable to the condition (1) or the condition (3), the actual reaction force command value is calculated using the corrected longitudinal gain Glongitudinal = 1.5. On the other hand, when the current traveling state satisfies the condition (2) and in the normal state, the actual reaction force command value is calculated using the longitudinal gain Glongitudinal = 1.
[0047]
In step S109, the left-right direction control command value, that is, the steering reaction force control command value FS to the steering reaction force control device 60 is calculated from the left-right risk potential RPlateral calculated in step S106. In accordance with the left-right direction risk potential RPlateral, the greater the risk potential, the larger the steering reaction force is generated in the direction of returning the steering angle of the steering wheel, that is, in the direction of returning the steering wheel to the neutral position.
[0048]
FIG. 9 shows the relationship between the left-right risk potential RPlateral and the steering reaction force control command value FS. In FIG. 9, when the left-right risk potential RPlateral is positive, it indicates that the risk potential is in the right direction, and when the left-right risk potential RPlateral is negative, it indicates that the risk potential is in the left direction. ing.
[0049]
As shown in FIG. 9, when the absolute value of the left-right risk potential RPlateral is smaller than the predetermined value RPmax, the steering reaction force in the direction of returning the steering wheel to the neutral position increases as the absolute value of the risk potential increases. A steering reaction force control command value FS is set. When the absolute value of the left-right risk potential RPlateral is greater than or equal to a predetermined value RPmax, the maximum steering reaction force control command value FSmax is set so that the steering wheel is quickly returned to the neutral position.
[0050]
Further, a predetermined left-right gain Glateral is added to the calculated steering reaction force control command value FS to obtain an actual reaction force command value. When the current traveling state is applicable to the condition (2) or the condition (3), the actual reaction force command value is calculated using the corrected lateral gain Glateral = 1.5. On the other hand, when the current traveling state satisfies the condition (1) and in the normal state, the actual reaction force command value is calculated using the lateral gain Glateral = 1.
[0051]
In step S110, the front / rear direction control command values FA and FB calculated in step S108 are output to the accelerator pedal reaction force control device 80 and the brake pedal reaction force control device 90, and the left / right direction control command value FS calculated in step S109 is steered. Output to reaction force control command value 60. As a result, the series of processes is completed.
[0052]
Thus, in the first embodiment described above, the following effects can be obtained.
(1) The controller 50 determines the traveling conditions such as the relative position of the other vehicle existing in front of or behind the host vehicle and its moving direction (relative speed), the traveling vehicle speed of the host vehicle, and the relative position of the host vehicle to the white line. Recognize and calculate the risk potential RP for each obstacle based on the driving situation. Based on the risk potential RP, the controller 50 controls the operation of the vehicle device so as to prompt the driver to perform driving operations related to the front-rear motion and the left-right motion of the host vehicle. At this time, the ratio of the operation assistance in the front-rear direction and the left-right direction for the driver is corrected according to the traveling state of the host vehicle. In other words, since the operation instruction from the important direction is corrected so as to increase, more important information can be transmitted in an easy-to-understand manner to the driver, and the driving operation can be appropriately promoted in the direction in which the risk potential RP is lowered.
(2) By correcting the control amount in the front-rear direction and the control amount in the left-right direction by the vehicle device according to the traveling state, the operation assistance in the front-rear direction and the left-right direction is corrected. Thereby, the operation instruction from the important direction can be easily transmitted to the driver.
(3) The front-rear direction control amount and the left-right direction control amount of the vehicle device are corrected according to the host vehicle speed. Specifically, when the host vehicle speed is equal to or higher than a predetermined vehicle speed, the longitudinal control amount is corrected so as to increase. Therefore, the risk potential RP from a more important direction is transmitted to the driver, and the driving operation is performed in an appropriate direction. Can be encouraged.
(4) The front-rear direction control amount and the left-right direction control amount of the vehicle device are corrected depending on whether or not the host vehicle is in a city running state. Specifically, since the left / right direction control amount is corrected to increase during city driving, the risk potential RP from a more important direction is transmitted to the driver, and the driving operation is encouraged in an appropriate direction. it can.
(5) The front-rear direction control amount and the left-right direction control amount of the vehicle device are corrected according to the driver's fatigue level. Specifically, when the driver is tired, the absolute value of the risk potential RP is corrected so that both the front-rear direction control amount and the left-right direction control amount are increased. Can be communicated to the driver.
(6) The front-rear direction control amount and the left-right direction control amount of the vehicle device are corrected according to the traveling environment of the host vehicle. Specifically, during bad weather such as rain and fog or during night driving, the absolute value of the risk potential RP is corrected so that both the front-rear direction control amount and the left-right direction control amount increase. It can be easily communicated to the driver.
(7) Since the operation reaction force generated by the accelerator pedal 82 is controlled in order to promote the driving operation related to the longitudinal movement of the host vehicle, the acceleration / deceleration operation by the driver can be appropriately assisted.
(8) Since the reaction force generated by the brake pedal 92 is controlled in order to promote the driving operation related to the longitudinal movement of the host vehicle, the driver's acceleration / deceleration operation can be appropriately assisted.
(9) Since the steering reaction force of the steering wheel is controlled in order to promote the driving operation related to the left-right motion of the host vehicle, the steering operation by the driver can be assisted appropriately.
(10) The risk potential RP was calculated as a function of the margin time TTC to the obstacle, and the longitudinal component RPlongitudinal and the lateral component RPlateral of the risk potential RP were calculated. Since the front-rear direction control amount and the left-right direction control amount are set based on the front-rear direction component RPlongitudinal and the left-right direction component RPlateral, depending on the distribution of the risk potential RPk generated by each obstacle k, It is possible to appropriately assist the driving operation in the left-right direction.
[0053]
<< Second Embodiment >>
Next, a vehicle driving assistance device according to a second embodiment of the present invention will be described. The configuration of the vehicle driving operation assisting device according to the second embodiment is the same as that of the first embodiment shown in FIGS. Here, differences from the first embodiment will be mainly described.
[0054]
As in the first embodiment, the controller 50 corrects the operation reaction force control amount in the front-rear direction and the left-right direction according to the traveling state. However, in the second embodiment, the operational reaction force control amount is corrected by calculating the risk gain Grp corresponding to the direction of each obstacle present around the vehicle and correcting the risk potential RP.
[0055]
How such reaction force control command values are determined in such control will be described below with reference to FIG. FIG. 10 is a flowchart showing the procedure of the driving assistance control process in the controller 50 according to the second embodiment of the present invention. This processing content is continuously performed at regular intervals, for example, every 50 msec.
[0056]
-Processing flow of controller 50 (FIG. 10)-
The processing in steps S201 to S203 is the same as the processing in steps S101 to S103 in the flowchart of FIG.
[0057]
In step S204, a risk gain Grp for correcting the risk potential RP corresponding to the running state and the direction in which the obstacle exists is calculated. First, in order to correct the risk potential RP according to the traveling state and the obstacle direction, the current traveling state is determined for the above-mentioned conditions (1) to (3) (see FIG. 6), and the risk potential RP correction method That is, a method of correcting the operation reaction force control amount is determined. And in order to implement | achieve this correction | amendment, the risk gain Grp is set according to the presence direction (theta) k of the obstruction k.
[0058]
FIG. 11 shows an example of the characteristic of the risk gain Grp with respect to the direction k of the obstacle k. In FIG. 11, the horizontal axis represents the absolute value of the direction k of the obstacle k relative to the host vehicle, and the vertical axis represents the risk gain Grp. Θk = 0 deg when the obstacle k exists in front of the vehicle, θk = 180 deg when it exists on the rear side of the vehicle, and | θk | = 90 deg when the obstacle k exists on the right side or the left side of the vehicle. .
[0059]
As shown in FIG. 11, when the traveling state is the condition (1), for example, there is a preceding vehicle, the risk gain Grp = 2 when the direction θk = 0 of the obstacle k, and the direction θk of the obstacle k. As the absolute value of increases, the risk gain Grp decreases. In the condition (1), when the obstacle k exists rearward from the side and 90 ≦ | θk | ≦ 180, the risk gain Grp = 1. When the traveling state is the condition (2), for example, there are motorcycles on the left and right sides of the vehicle, the risk gain Grp = 2 when the direction of the obstacle k | θk | = 90 deg, and the direction θk of the obstacle k The risk gain Grp decreases as the absolute value decreases or increases. In the condition (2), when the obstacle k exists in front of or behind the vehicle and | θk | = 0, 180 deg, the risk gain Grp = 1. When the traveling state is the condition (3), the risk gain Grp = 1.5 regardless of the direction θk of the obstacle k. When the running state is a normal state that does not apply to any of the conditions (1) to (3), the risk gain Grp = 1.
[0060]
The controller 50 calculates the risk gain Grp corresponding to the existence direction θk for each obstacle k according to FIG. 11 according to the traveling state and the obstacle state.
[0061]
In step S205, the risk potential RPk for each obstacle k is calculated using the margin time TTCk calculated in step S203 and the risk gain Grp calculated in step S204. Here, the risk potential RPk for each obstacle k is obtained by the following (formula 6).
[Formula 6]
RPk = (1 / TTCk) × wk × Grp (Formula 6)
Here, wk: indicates the weight of the obstacle k. The calculation method of the weight wk is the same as that in the first embodiment described above. The risk potential RPk is corrected according to the running state and the direction of the obstacle by integrating the risk gain Grp, and the risk potential RPk increases as the risk gain Grp increases.
[0062]
In step S206, components in the vehicle front-rear direction are extracted from the risk potential RPk for each obstacle k calculated in step S205 and added to calculate a total front-rear risk potential for all obstacles existing around the vehicle. . The front-rear direction risk potential RPlongitudinal can be calculated using (Equation 4) as in the first embodiment.
[0063]
In step S207, components in the vehicle left-right direction are extracted from the risk potential RPk for each obstacle k calculated in step S205 and added to calculate a comprehensive left-right risk potential for all obstacles present around the vehicle. . The left-right direction risk degree RPlateral can be calculated using (Equation 5) as in the first embodiment.
[0064]
The subsequent processing in steps S208 to S210 is the same as the processing in steps S108 to S110 in the flowchart of FIG. 3 described above.
[0065]
Note that the risk gain characteristics shown in FIG. 11 can also be expressed as shown in FIG. 12 corresponding to the vertical and horizontal directions of the vehicle.
[0066]
Thus, in the second embodiment described above, the following effects can be obtained in addition to the effects of the first embodiment described above.
(1) The risk potential RP is corrected according to the traveling state, and the front-rear direction control amount and the left-right direction control amount of the vehicle device are set based on the corrected risk potential RP, thereby assisting operation assistance in the front-rear direction and the left-right direction. to correct. Thereby, the operation instruction from the important direction can be easily transmitted to the driver.
(2) The risk potential RP for the obstacle is corrected according to the vehicle speed and the direction in which the obstacle exists. For example, when the host vehicle speed is equal to or higher than a predetermined vehicle speed and there is a preceding vehicle, the gain Grp integrated with the risk potential RP for the preceding vehicle is set to be larger than that in the normal state. As a result, the control amount in the front-rear direction larger than that in the normal state is set, and the risk potential RP from a more important direction can be transmitted to the driver in an easy-to-understand manner and the driving operation can be promoted in an appropriate direction. Moreover, since the risk potential RP is corrected according to the direction θk of each obstacle k, a more appropriate operation instruction can be given according to the situation of each obstacle k.
(3) The risk potential RP for the obstacle is corrected according to the direction of the obstacle and whether or not the host vehicle is in the urban area. For example, when a motorcycle or the like is present beside the vehicle while traveling in an urban area, the gain Grp integrated with the risk potential RP for the motorcycle is set larger than that in the normal state. As a result, a left / right control amount larger than that in the normal state is set, and the risk potential RP from a more important direction can be transmitted to the driver in an easy-to-understand manner to drive the driving operation in an appropriate direction. Moreover, since the risk potential RP is corrected according to the direction θk of each obstacle k, a more appropriate operation instruction can be given according to the situation of each obstacle k.
(4) The risk potential RP for the obstacle is corrected according to the driver's fatigue level. Specifically, when the driver is tired, the gain Grp integrated with the risk potential RP is set larger than that in the normal state. Thereby, the front-rear direction control amount and the left-right direction control amount larger than the normal state are set, and the risk potential RP can be easily transmitted to the driver.
(5) The risk potential RP for the obstacle is corrected according to the traveling environment of the host vehicle. Specifically, the gain Grp integrated to the risk potential RP is set to be larger than that in the normal state during bad weather such as rain or fog and during night driving. Thereby, the front-rear direction control amount and the left-right direction control amount that are larger than the normal state are set, and the risk potential RP can be transmitted to the driver in an easily understandable manner.
[0067]
In the above embodiment, when the current running state of the vehicle meets a plurality of conditions, the gains Glongitudinal, Glateral, and Grp are set so as to give the driver the greatest operational assistance. For example, in the first embodiment, when the traveling state satisfies the conditions (1) and (3), the correction corresponding to the condition (3) is performed. Thereby, the operation assistance in the front-rear direction and the left-right direction is greater than in the normal state, and the risk potential RP can be easily communicated to the driver.
[0068]
In the above embodiment, the driving state is determined under three conditions and the correction method for operation assistance is determined. However, if the risk potential from a more important direction can be easily communicated to the driver, the driving state is further increased. It is also possible to determine a correction method by determining many or few conditions.
[0069]
In the above embodiment, the risk potential RP is calculated by multiplying the reciprocal of the margin time TTC by the weight w. However, the present invention is not limited to this. The risk potential RP is defined as a function of the margin time TTC, and the same effect can be obtained as long as the risk potential RP increases as the margin time TTC decreases. Furthermore, if the risk potential for the obstacle can be accurately shown according to the obstacle situation around the host vehicle, the risk potential can be calculated without using the margin time TTC.
[0070]
Further, when calculating the margin time TTCk and the risk potential RPk, the relative distance to each obstacle k, the relative speed variations σ (Dk), σ (Vrk), and the weight wk of each obstacle k are considered. However, it is not limited to this. For example, the margin time TTCk can be calculated without considering the variation σ, or the risk potential RPk can be calculated without considering the weight wk. When setting the variation σ, the variation σ can be set only according to the type of detector, or the variation σ can be determined by combining the type of detector and the type of obstacle. However, by determining the variation σ according to the type of the detector and the type of the obstacle and considering the variation σ and the weight wk, it is possible to calculate a more accurate margin time and risk potential.
[0071]
In the above-described embodiment, the configuration is such that the longitudinal movement of the vehicle is controlled using the accelerator pedal reaction force control device 80 and the brake pedal reaction force control device 90. However, the present invention is not limited to this. Only one can be used. That is, in the present invention, not only the accelerator pedal 82, the brake pedal 92, or the steering wheel 62, but also the operation of various vehicle devices is controlled so that the driving operation in the vehicle front-rear direction and the left-right direction by the driver is in an appropriate direction. It only needs to be encouraged.
[0072]
In the above embodiment, the ratio of the front / rear driving operation assistance and the left / right driving operation assistance is corrected by correcting the front / rear / left / right control amount or the risk potential RP according to the running state. However, by combining both corrections, for example, the risk potential RP is corrected according to the running state, the front / rear / left / right direction control amount is calculated based on the corrected risk potential RP, and the front / rear / The left-right direction control amount can also be corrected.
[0073]
In the above embodiment, the brake assist force is generated by using the negative pressure of the engine by the brake booster 91. However, the present invention is not limited to this. For example, the brake assist force is generated by using oil pressure by computer control. You can also.
[0074]
The vehicle to which the vehicle driving operation assistance method according to the present invention is applied is not limited to the configuration shown in FIG.
[0075]
In the embodiment of the vehicle driving operation assisting device according to the present invention described above, the laser radar 10, the front camera 20, the rear side camera 21, and the vehicle speed sensor 30 are used as the obstacle detection means. The present invention is not limited to this as long as an obstacle present in the surroundings can be detected. For example, a millimeter wave radar can also be used. Further, the controller 50 is used as a risk potential calculation means, a running state detection means, an operation auxiliary correction means, an operation amount correction means, and a risk potential correction means. In addition, a steering reaction force control device 60, an accelerator pedal reaction force control device 80, and a brake pedal reaction force control device 90 were used as vehicle equipment control means. However, the vehicle driving assist device according to the present invention is not limited to these. For example, an image processing apparatus that performs image processing on image signals input from the front camera 20 and the rear side camera 21 may be provided, and this may be used as an obstacle detection unit.
[Brief description of the drawings]
FIG. 1 is a system diagram of a vehicle driving assistance device according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of a vehicle equipped with the vehicle driving assist device shown in FIG.
FIG. 3 is a flowchart showing a processing procedure of a driving assistance control program in the vehicle driving assistance device of the first embodiment.
4A is a diagram showing the magnitude of variation in relative distance depending on the sensor type, and FIG. 4B is a diagram showing the magnitude of variation in relative speed depending on the sensor type.
FIG. 5A is a diagram showing the magnitude of relative distance variation due to obstacle types, and FIG. 5B is a diagram showing the magnitude of relative speed variation due to obstacle types.
FIG. 6 is a diagram showing conditions in the first embodiment.
FIG. 7 is a graph showing characteristics of an accelerator pedal reaction force control command value with respect to a front-rear risk potential.
FIG. 8 is a diagram showing characteristics of a brake pedal reaction force control command value with respect to a front-rear risk potential.
FIG. 9 is a diagram showing a characteristic of a steering reaction force control command value with respect to a left-right risk potential.
FIG. 10 is a flowchart showing a processing procedure of a driving assistance control program in the vehicle driving assistance device of the second embodiment.
FIG. 11 is a diagram illustrating an example of a characteristic of a risk gain Grp with respect to an obstacle existing direction.
FIG. 12 is a diagram illustrating an example of a characteristic of a risk gain Grp with respect to an obstacle existing direction.
[Explanation of symbols]
10: Laser radar
20: Front camera
21: Rear side camera
30: Vehicle speed sensor
50: Controller
60: Steering reaction force control device
80: Accelerator pedal reaction force control device
90: Brake pedal reaction force control device

Claims (16)

Obstacle detection means for detecting obstacles around the host vehicle;
Risk potential calculation means for calculating a risk potential for the obstacle of the host vehicle based on a signal from the obstacle detection means;
Vehicle equipment control means for controlling the operation of the vehicle equipment based on a signal from the risk potential calculation means so as to prompt the driver to perform a driving operation related to the back-and-forth motion and left-right motion of the host vehicle;
Traveling state detecting means for detecting the traveling state of the host vehicle;
According to the driving state detected by the driving state detection unit, operation assist correction means for correcting a ratio of driving operation assistance in the front-rear direction and driving operation assistance in the left-right direction with respect to the driver,
The traveling state detecting means detects the vehicle speed as the traveling state,
The operation assistance correction means has a larger ratio of driving assistance in the front-rear direction when the own vehicle speed detected by the traveling state detection means is greater than or equal to a predetermined value, compared to when the own vehicle speed is less than the prescribed value. A driving operation assisting device for a vehicle, characterized in that correction is performed. The vehicle driving assistance device according to claim 1,
The operation assist correction unit includes an operation amount correction unit that corrects a control amount in the front-rear direction and a control amount in the left-right direction by the vehicle device control unit,
The operation amount correction means corrects the front-rear direction control amount to be larger when the host vehicle speed is equal to or higher than the predetermined value compared to when the host vehicle speed is lower than the predetermined value, thereby assisting the driver in driving operation. A driving operation assisting device for a vehicle, wherein The vehicle driving operation assistance device according to claim 2,
The traveling state detection means detects whether the host vehicle is in an urban driving state in addition to the host vehicle speed as the traveling state,
The vehicle operation assisting device, wherein the operation amount correction unit corrects the front-rear direction control amount and the left-right direction control amount according to a detection result of the traveling state detection unit. The vehicle driving operation assistance device according to claim 2,
The traveling state detection means detects the driver's fatigue level as the traveling state, in addition to the vehicle speed,
The operation amount correction means corrects the front-rear direction control amount and the left-right direction control amount according to the host vehicle speed and the degree of fatigue detected by the running state detection means. apparatus. The vehicle driving operation assistance device according to claim 2,
The travel state detection means detects the travel environment of the host vehicle as the travel state, in addition to the host vehicle speed,
The operation amount correction means corrects the front-rear direction control amount and the left-right direction control amount in accordance with the host vehicle speed and the travel environment detected by the travel state detection means. apparatus. The vehicle driving assistance device according to claim 1,
The operation assistance correction means includes risk potential correction means for correcting the risk potential calculated by the risk potential calculation means,
The risk potential correction means corrects the risk potential according to the driving state, and causes the vehicle equipment control means to set a control amount in the front-rear direction and a control amount in the left-right direction based on the corrected risk potential, A driving operation assisting device for a vehicle, wherein the driving operation assisting for a person is corrected. The vehicle driving operation assistance device according to claim 6,
The obstacle detecting means detects the direction of the obstacle;
The risk potential correcting means is a fault that exists in front of the own vehicle when the own vehicle speed detected by the running state detecting means is equal to or higher than the predetermined value, compared to a case where the own vehicle speed is less than the predetermined value. A vehicular driving assisting device, wherein the risk potential is corrected so that the risk potential for an object is increased. The vehicle driving assistance device according to claim 7,
The traveling state detection means detects whether the host vehicle is in an urban driving state in addition to the host vehicle speed as the traveling state,
The risk potential correcting unit corrects a risk potential for the obstacle according to a detection result of the traveling state detecting unit and a direction of the obstacle detected by the obstacle detecting unit. Driving operation assist device for vehicles. The vehicle driving assistance device according to claim 7,
The traveling state detection means detects the driver's fatigue level as the traveling state, in addition to the vehicle speed,
The risk potential correcting means calculates a risk potential for the obstacle according to the own vehicle speed and the degree of fatigue detected by the running state detecting means and the direction of presence of the obstacle detected by the obstacle detecting means. A vehicular driving operation assisting device that corrects the vehicle. The vehicle driving assistance device according to claim 7,
The travel state detection means detects the travel environment of the host vehicle as the travel state, in addition to the host vehicle speed,
The risk potential correction means calculates the risk potential for the obstacle according to the host vehicle speed and the traveling environment detected by the traveling state detection means, and the presence direction of the obstacle detected by the obstacle detection means. A vehicular driving operation assisting device that corrects the vehicle. In the driving assistance device for vehicles according to any one of claims 1 to 10,
The vehicular equipment control means includes at least an accelerator pedal reaction force control means for controlling an operation reaction force generated by an accelerator pedal. The vehicle driving assist device for a vehicle according to any one of claims 1 to 11,
The vehicle equipment control means comprises at least a brake pedal reaction force control means for controlling an operation reaction force to be generated by a brake pedal. The vehicle driving assist device for a vehicle according to any one of claims 1 to 12,
The vehicle equipment control means includes at least a steering reaction force control means for controlling a steering reaction force of a steering wheel. In the driving assistance device for a vehicle according to any one of claims 1 to 13,
The obstacle detection means detects a relative distance and a relative speed to the obstacle,
The risk potential calculation means calculates a margin time obtained by dividing a relative distance to the obstacle by a relative speed, calculates a risk potential for the obstacle as a function of the margin time, and depends on a direction to the obstacle Calculating the longitudinal component and the lateral component of the risk potential,
The vehicle device control means sets the front-rear direction control amount and the left-right direction control amount of the vehicle device based on the front-rear direction risk potential and the left-right direction risk potential calculated by the risk potential calculation unit. Driving operation assist device for vehicles. Detect obstacles around your vehicle,
Based on the detected state of the obstacle, the risk potential for the obstacle of the host vehicle is calculated,
Based on the calculated risk potential, the operation of the vehicle equipment is controlled so as to prompt the driver to perform driving operations related to the front-rear motion and the left-right motion of the host vehicle,
Detecting the running state of the vehicle,
According to the driving state, the ratio of the driving operation assistance in the front-rear direction and the driving operation assistance in the left-right direction for the driver is corrected,
Detecting the vehicle speed as the running state,
When the host vehicle speed is equal to or higher than a predetermined value , the driving operation assist method for the vehicle is corrected so that the ratio of the driving operation assist in the front-rear direction is larger than when the host vehicle speed is less than the predetermined value. . A vehicle comprising the vehicular driving assist device according to any one of claims 1 to 14 .

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