JP4811075B2 - Avoidance operation calculation device, avoidance control device, vehicle including each device, avoidance operation calculation method, and avoidance control method - Google Patents

Description

  The present invention relates to an avoidance operation calculation device, an avoidance control device, a vehicle including each device, an avoidance operation calculation method, and an avoidance control method for avoiding an obstacle on a road on which the host vehicle is traveling.

  Conventionally, it is possible for a vehicle to detect an obstacle existing ahead of the host vehicle on the road on which the vehicle (the host vehicle) is traveling. When an obstacle is detected, the host vehicle is decelerated by braking control. To prevent the host vehicle from reaching the position of the obstacle.

However, there is a case where it is impossible to avoid reaching the position of the obstacle even if the host vehicle is decelerated. Therefore, the host vehicle is operated by performing braking control and steering control so that the host vehicle A motion control device that avoids reaching the position is considered. In this motion control device, when it is determined that the obstacle cannot be avoided even if the host vehicle is decelerated by the braking control, the first yaw rate necessary for turning to avoid the obstacle and the current vehicle are determined. The generated second yaw rate is calculated, the first yaw rate and the second yaw rate are compared, the larger absolute value is set as the target yaw rate, and the braking force of the left and right wheels is determined based on this target yaw rate. Since the turning force is applied to the host vehicle by the difference and the steering, the host vehicle can be prevented from reaching the position of the obstacle (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2001-247023

  However, in the above-described motion control device, turning force is applied to the host vehicle by braking control and steering control. However, in order to achieve a target yaw rate calculated to avoid a front obstacle by turning, sudden braking and sudden braking are performed. There is a possibility that a proper steering is required. In general, in a vehicle, when a driving operation such as sudden braking and sudden steering is executed, a force exceeding the maximum value (limit value) of the grip force of the tire may be applied to the vehicle.

  Accordingly, an object of the present invention is to provide a driving operation amount that allows the host vehicle to avoid an obstacle by braking control and steering control without applying a force exceeding the maximum grip force of the tire of the host vehicle to the vehicle. An object of the present invention is to provide an avoidance operation calculation device that calculates, an avoidance control device that performs a driving operation calculated by the avoidance operation calculation device, a vehicle including these devices, an avoidance operation calculation method, and an avoidance operation calculation method.

  In order to solve the above-described problem, an avoidance operation calculation device according to the present invention detects an obstacle detection unit that detects an obstacle existing on a road ahead of the host vehicle, and detects a traveling state of the host vehicle. Vehicle information detection means; avoidance operation amount generation means for generating an avoidance operation amount for the vehicle to avoid the obstacle based on detection information from the vehicle information detection means and the obstacle detection means; The avoidance operation amount generating means includes the avoidance operation amount within a range where a combined force of acceleration force, deceleration force and lateral force generated in the host vehicle is smaller than a maximum value of the grip force of the tire of the host vehicle. Is calculated.

  According to the avoidance operation calculating device according to the present invention, the combined force of acceleration force, deceleration force, and lateral force generated in the host vehicle by the amount of avoidance operation calculated to avoid the obstacle is calculated as the grip force of the tire of the host vehicle. It can be made smaller than the maximum value. For this reason, it is possible to calculate an avoidance operation amount that allows the host vehicle to avoid an obstacle with a stable behavior.

  The present invention will be described in detail with reference to the embodiments shown in FIGS.

  FIG. 1 is a plan view schematically showing a vehicle 12 in which an avoidance operation calculation device 10 according to the present invention and an avoidance control device 11 having the avoidance operation calculation device 11 are adopted, and FIG. 2 is a block diagram showing the avoidance control device 11. It is.

  When the obstacle 14 (see FIG. 3) exists on the road 13 on which the vehicle 12 (the host vehicle) travels, the avoidance operation calculation device 10 calculates the amount of driving operation that the vehicle 12 can avoid the obstacle 14. Is to be calculated. The avoidance control device 11 includes the avoidance operation calculation device 10 and the vehicle motion control means 15, and the vehicle motion control means 15 executes the driving operation amount calculated by the avoidance operation calculation device 10.

  The vehicle 12 includes a camera 16, a vehicle speed sensor 17, a yaw rate sensor 18, an acceleration sensor 19, a microprocessor 20, a steering angle sensor 21, a steering motor 22, a steering angle servo controller 23, and a brake controller. 24, a hydraulic control system 25, and a brake 26 are provided. In the first embodiment, the vehicle 12 employs a rack-pinion type front wheel steering mechanism, and the steering angle sensor 21, the steering motor 22, and the steering angle servo controller 23 are provided corresponding to the front wheel steering mechanism. Yes. As will be described later, the steering angle sensor 21 is attached to the front wheel steering mechanism and is electrically connected to the steering angle servo controller 23. The steering angle servo controller 23 is electrically connected to the steering motor 22 and the microprocessor 20. The microprocessor 20 is electrically connected to each of the camera 16, the vehicle speed sensor 17, the yaw rate sensor 18, the acceleration sensor 19, and the brake controller 24.

  The camera 16 is disposed in the passenger compartment of the vehicle 12 and can capture the front of the vehicle 12. In the first embodiment, two cameras 16 are provided as a pair on the left and right, and an acquisition information processing means 27 (see FIG. 2) of the microprocessor 20 described later captures an image from the image signal from the camera 16. In addition to the generation, it is possible to process the information in the image in three dimensions, for example, to detect the distance from the position where the vehicle 12 is present to the obstacle 14 (see FIG. 3). The camera 16 outputs an image signal to the vehicle information processing unit 28 and the obstacle information processing unit 29 (see FIG. 2) of the acquisition information processing unit 27 described later.

  The vehicle speed sensor 17 generates a signal for detecting the traveling speed of the vehicle 12. In the first embodiment, the vehicle speed sensor 17 includes a rotary encoder attached to the wheel of the vehicle 12, and is a pulse signal proportional to the rotation of the wheel. Is output to the vehicle information processing unit 28 (see FIG. 2).

  The yaw rate sensor 18 outputs a signal for detecting a yaw rate generated in the vehicle 12 to the vehicle information processing unit 28 (see FIG. 2), and is a known device configured using a crystal resonator or a semiconductor. Is being used.

  The acceleration sensor 19 outputs a signal for detecting acceleration in a specific direction generated in the vehicle 12 to the vehicle information processing unit 28 (see FIG. 2), and is configured using, for example, a piezoelectric element. Other known devices can be used. In the first embodiment, the acceleration sensor 19 is set to generate a signal corresponding to the acceleration in the width direction generated in the vehicle 12.

  The microprocessor 20 is an integrated circuit including an A / D conversion circuit, a D / A conversion circuit, a central processing unit, a memory, and the like. The acquired information processing means 27, which is a program stored in the memory, the avoidance operation amount It has a generating means 30 and a memory 31 (see FIG. 2). As will be described later, in the microprocessor 20, the acquisition information processing unit 27 processes signals from the camera 16 and the sensors 17 to 19 to generate various information, and the avoidance operation amount generation unit 30 receives the information from the acquisition information processing unit 27. The avoidance operation amount for avoiding the obstacle 14 (see FIG. 2) is calculated based on the various information, and a signal corresponding to the calculated avoidance operation amount is output to the steering angle servo controller 23 and the brake controller 24. Thus, since the microprocessor 20 calculates the avoidance operation amount according to the signals from the camera 16 and the sensors 17 to 19, the camera 16, the sensors 17 to 19, and the microprocessor 20 serve as the avoidance operation calculation device 10. Function. The memory 31 of the microprocessor 20 can store information and can exchange information with the acquired information processing means 27 and the avoidance operation amount generating means 30.

  The steering angle servo controller 23 includes a microprocessor for control calculation and a booster circuit (not shown) for driving the steering motor 22, and is output from the avoidance operation amount generation means 30 of the microprocessor 20. Servo control is executed with the avoidance operation amount corresponding to the signal to be output, that is, the steering angle (steering amount) corresponding to the output signal as a target.

  The steering angle sensor 21 outputs a signal for detecting the steering angle (steering amount) actually steered to the steering angle servo controller 23, and the steering angle servo controller 23 servo-controls information based on this signal. Used as feedback information in In the first embodiment, the steering angle sensor 21 outputs a signal corresponding to the rack stroke amount in the rack-and-pinion type front wheel steering mechanism to the steering angle servo controller 23, and based on this signal, the steering angle servo controller 23 controls the steering angle (steering). Amount) can be detected.

  The steering motor 22 performs steering according to a signal from the steering angle servo controller 23 separately from the operation of the driver. In the first embodiment, the pinion gear in the rack-pinion type front wheel steering mechanism is used as a motor. Steer by rotating with.

  In this way, the steering angle servo controller 23 drives the steering motor 22 to perform steering, and the steering angle sensor 21 feeds back the steering amount by this steering to the steering angle servo controller 23, whereby the microprocessor 20. Since the steering amount of the avoidance operation amount calculated by the avoidance operation amount generation means 30 (see FIG. 2), that is, the steering amount of the avoidance operation amount calculated by the avoidance operation calculation device 10 is executed. The steering angle sensor 21, the steering motor 22, and the steering angle servo controller 23 function as a steering control unit 32 in the vehicle motion control unit 15.

  The brake 26 is provided in each of the four tires 33 of the vehicle 12, and the braking of each tire 33 can be controlled by braking. The operation of each brake 26 is controlled by the hydraulic pressure from the hydraulic control system 25, and a brake controller 24 is electrically connected to a control valve (not shown) of the hydraulic control system 25.

  In addition to the driver's operation, the brake controller 24 determines the braking force applied to the vehicle 12 required to execute the deceleration operation amount out of the avoidance operation amount calculated by the avoidance operation amount generation means 30 of the microprocessor 20. This is a microprocessor that calculates a braking force (grip force) to be applied to each tire 33 based on it. The brake controller 24 controls the opening / closing operation of a control valve (not shown) of the hydraulic control system 25 so that each tire 33 exhibits the calculated braking force. Accordingly, the vehicle 12 can be decelerated and a yaw moment can be generated in the vehicle 12 by providing a difference in the braking force between the left and right wheels.

  As described above, the brake controller 24 controls the control valve (not shown) of the hydraulic control system 25, whereby the avoidance operation amount calculated by the avoidance operation amount generation means 30 (see FIG. 2) of the microprocessor 20 is set. Since the deceleration operation amount is executed by exerting the braking force of each tire 33, each brake 26, hydraulic control system 25, brake controller 24 and each tire 33 are used as the braking motion control means 34 in the vehicle motion control means 15. Function.

  As described above, the vehicle motion control unit 15 includes the steering control unit 32 and the braking motion control unit 34, and executes the avoidance operation amount calculated by the avoidance operation calculation device 10. Therefore, the avoidance operation calculation device 10 and The vehicle motion control means 15 constitutes an avoidance control device 11 (see FIG. 2).

  As described above, the avoidance operation calculation device 10, as shown in FIG. 2, acquires the information processing means 27 that processes the signals from the camera 16 and the sensors 17 to 19 to generate various information, and the generated information processing means 27. And an avoidance operation amount generation means 30 that calculates an avoidance operation amount based on various information. The acquired information processing unit 27 includes a host vehicle information processing unit 28, an obstacle information processing unit 29, and a reachability determination unit 35, and the host vehicle information processing is performed according to signals from the camera 16 and the sensors 17 to 19. The unit 28 generates information on the own vehicle (vehicle 12) (see FIG. 3), and the obstacle information processing unit 29 generates information on the obstacle 14.

  The own vehicle information generated by the own vehicle information processing unit 28 includes information on the position of the vehicle 12 with respect to the traveling road 13, information on the attitude angle θ of the vehicle 12, information on the yaw rate γ generated in the vehicle 12, Information on the generated slip angle β and information on the running speed v of the vehicle 12 are mentioned. Here, the posture angle θ is an angle formed by the direction in which the vehicle 12 travels with respect to the direction of the road 13, that is, the direction in which the running shape of the road 13 extends, and the slip angle β is based on actual steering. An angle formed by the direction in which the vehicle 12 actually travels relative to the predicted traveling direction of the vehicle 12.

  The position of the vehicle 12 with respect to the road 13 can be detected by subjecting the image signal output from the paired camera 16 to image processing by the own vehicle information processing unit 28.

  For example, if it is assumed that the road is a straight line, the posture angle θ can be obtained by estimating the angle formed by the boundary portion of the road 13 and the direction in which the vehicle 12 (own vehicle) is directed by image processing. it can. It may be calculated by determining an appropriate initial value and integrating the output value from the yaw rate sensor 18. The appropriate initial value may be, for example, the traveling direction of the vehicle 12 traveling in the direction of the road 13, that is, the direction in which the vehicle 12 has traveled before the avoidance driving operation is performed.

  The vehicle information processing unit 28 can detect the yaw rate γ and the traveling speed v from the signals output by the yaw rate sensor 18 and the vehicle speed sensor 17 as described above.

The slip angle β can be obtained by the following equation (1), where v _{x is} the speed in the front-rear direction of the vehicle 12 and v _y is the speed in the width direction of the vehicle 12.

β = arctan (v _y / v _x ) (1)
In this case, for example, in the vehicle 12, it is assumed that the speed component in the width direction is sufficiently smaller than the speed component in the front-rear direction, and v _x is v. Further, v _y can be obtained by integrating the output of the acceleration sensor 19. For this reason, the approximate value of the slip angle β can be obtained from the equation (1). There is also known a known technique for estimating the slip angle with higher accuracy from the signals such as the wheel speed from the vehicle speed sensor 17, the yaw rate from the yaw rate sensor 18, and the lateral acceleration from the acceleration sensor 19. The slip angle β may be obtained using a technique.

  The obstacle information can be detected by the obstacle information processing unit 29 performing image processing on the image signal input from the paired cameras 16.

  As described above, the host vehicle information processing unit 28 functions as host vehicle information detection means in cooperation with the camera 16, the vehicle speed sensor 17, the yaw rate sensor 18, and the acceleration sensor 19. In cooperation with the camera 16, it functions as an obstacle detection means. In addition, since many methods are disclosed as a well-known technique about the obstacle detection method by image processing, the detailed description is abbreviate | omitted here.

Here, a coordinate system is set so that various information detected by the own vehicle information detecting means and the obstacle detecting means, a predicted traveling locus described later, and the like can be handled uniformly, and the information of the vehicle 12 and the obstacle 14 are coordinate values. In other words, they are associated with or expanded (see FIG. 3). In the first embodiment, a coordinate system is set by the reachability determination unit 35, and as shown in FIG. 3, the X axis along the direction of the road 13 is perpendicular to the X axis, that is, the Y axis in the width direction of the road 13. Is set. The coordinate origin can be arbitrarily selected. As an example, the origin of the X coordinate and the Y coordinate is set at the current position of the vehicle 12 in the first embodiment (see FIG. 3). By setting the coordinate system, the positions of the vehicle 12 and the obstacle 14 can be expressed by coordinate values. In the following description, the position of the vehicle 12 (own vehicle) is (X, Y) = (x, y) when viewed from the center of gravity, and the position of the obstacle 14 (pedestrian in the first embodiment) is set to (X, Y). ) = (X _p , y _p ). Further, the speed of the obstacle 14 is v _p , the speed in the direction of the road 13 is v _{px, and} the speed in the width direction of the road 13 is v _py .

  As shown in FIG. 2, the reachability determination unit 35 determines whether or not the vehicle 12 needs to calculate an avoidance operation amount for avoiding the obstacle 14 based on the own vehicle information and the information on the obstacle 14. Determine whether. Even if this is the case where the obstacle 14 is detected on the road 13, there is no possibility that the vehicle 12 that maintains the current traveling state (follows the predicted stationary trajectory) reaches the position of the detected obstacle 14. This is because it is not necessary to calculate the avoidance operation amount.

As an example of this determination method, in Example 1, it is determined that it is necessary to calculate the avoidance operation amount when both of the following expressions (2) and (3) are satisfied. As described above, the traveling speed v of the vehicle 12 is (v _x , v _y ), and the moving speed v _p of the obstacle 14 is (v _px , v _py ).

| X _p −x | / | v _px −v _x | ≦ TTC1 (2)
_{| Y p -y | / max (} | v py -v y |, v ymin) ≦ TTC2 (3)
However, max (a, b) is a function for selecting a large value between a and b. Further, _vymin is an arbitrary value other than 0, and the width of the vehicle 12 is B, and the average thickness of each attribute assumed as the obstacle 14 (this attribute will be described later) is C. It is assumed that the following formula (4) is satisfied.

TTC2 × v _ymin = (B + C) / 2 (4)
When | v _py −v _y | = 0, it is necessary to determine that the vehicle 12 reaches the position of the obstacle 14 when the value of | y _p −y | is smaller than (B + C) / 2. Therefore, it is necessary to switch the denominator of the expression (3).

Equation (2) indicates that in a situation where | v _px -v _x | = 0, the traveling speed v of the vehicle 12 is a number (km / s), and the obstacle 14 is sufficiently removed by the avoidance operation by the driver. Since it can be avoided, it is determined that the condition is not satisfied. Instead of this, in the formula (2), (v _y ≧ predetermined value> v _py ) may be used as the determination condition. This predetermined value may be set to a low speed that can avoid the obstacle 14 without performing the avoidance control by the avoidance operation amount in general.

  Here, in the first embodiment, since both conditions (2) and (3) are satisfied, TTC1 = TTC2. This TTC1 (= TTC2) is a parameter that takes a positive value representing the determination threshold, and for example, a value of about 3 to 4 seconds is set.

  As described above, in the microprocessor 20, the acquired information processing means 27 generates various desired information according to signals from the camera 16 and the sensors 17 to 19, and the avoidance operation amount generating means 30 is based on this information. The avoidance operation amount is calculated.

  The avoidance operation amount generation means 30 includes an own vehicle movement trajectory calculation means 36, an obstacle movement trajectory prediction means 37, an arrival prediction means 38, a frictional force limit setting means 39, an avoidance target position calculation means 40, and an avoidance operation. An amount calculation unit 41 and a buffer memory 42 are included.

When the own vehicle movement trajectory calculating means 36 sets an arbitrary deceleration d ₀ and decelerates the vehicle 12 by the deceleration d ₀ based on the current motion state of the vehicle 12 based on the own vehicle information, the current time The predicted decelerating movement trajectory predicted to be followed by the vehicle 12 during a predetermined time until is calculated. The deceleration d ₀ is a desired value as long as it is within a range smaller than the deceleration that can be generated in the vehicle 12 when the grip force (braking force) that is the maximum value is applied to the four tires 33 of the vehicle 12. Can be set to In the first embodiment, the deceleration d ₀ is the braking force (the tire shown in FIG. 5 to be described later) that allows each tire 33 to decelerate the vehicle 12 quickly and to allow a lateral force during the deceleration. It is set based on the friction circle.)

Here, the current time is T _0, and a time variable representing a time later than the current time T ₀ is t. Further, for example, as shown in FIG. 3, the vehicle 12 is located on the straight road 13, and running at the current time T ₀ at a speed v in the direction of the road 13. The predicted deceleration movement trajectory when the deceleration d ₀ is applied to the vehicle 12 can be expressed by the following equations (5) and (6).

_{x (t) = x (t} 0) + v (t 0) (t-t 0) -d 0 (t-t 0) 2/2 (5)
y (t) = y (t ₀ ) (6)
The obstacle movement trajectory predicting means 37 estimates the moving direction, moving speed, and attribute of the obstacle 14 from the detection history of the obstacle 14 so far, and performs the uniform linear motion while maintaining the moving speed estimated by the obstacle 14. The predicted obstacle movement trajectory is calculated under the assumption that it is performed. The attribute refers to characteristics such as size and shape as if the obstacle 14 is a pedestrian or a vehicle. In the first embodiment, the attribute of the obstacle 14 is determined according to the estimated attribute. Set the size.

Here, for example, as shown in FIG. 3, it is assumed that the obstacle 14 is moving in the direction parallel to the Y axis, that is, the road 13 in the width direction, and the position P ₀ of the obstacle 14 at the current time T ₀ is assumed. Is (x _p (t ₀ ), y _p (t ₀ )), and the estimated value of the moving speed of the obstacle 14 is a constant value v _p . Then, the movement speed of the obstacle 14 becomes (v _px , v _py ) = (0, v _p ), and the predicted obstacle movement locus that becomes the position of the obstacle 14 at time t is expressed by the following equations (7), (8 ).

x _p (t) = x _p (t ₀ ) (7)
y _p (t) = y _p (t ₀ ) + v _p (t−t ₀ ) (8)
If it is found that the obstacle 14 is stationary, the predicted obstacle movement trajectory is not calculated.

The arrival prediction means 38 decelerates the vehicle 12 based on the predicted deceleration movement locus calculated by the own vehicle movement locus calculation means 36 and the predicted obstacle movement locus calculated by the obstacle movement locus prediction means 37. _When the vehicle is decelerated at ₀ , it is determined whether or not the vehicle 12 reaches the position of the obstacle 14. The reaching prediction means 38, when judging that it reaches, with to reach the position of the obstacle 14 is set as the predicted time T _A to calculate a time to be expected, the evaluation start time has been detected obstacle 14 It is set as the time _{T S.} Furthermore, the arrival prediction means 38 calculates the arrival state between the vehicle 12 and the obstacle 14 when it is determined that the arrival is reached. Here, the arrival, the outer peripheral position and the part of the (outer periphery of the circle of radius r, which will be described later in Example 1), an outer peripheral position of the vehicle 12 (the length which will be described later in Example 1 of the obstacle 14 (L F ₊ L _{R 2} ) refers to a state in which a part of the outer periphery of the rectangle of width B coincides, and the reached state refers to the mutual positional relationship when the vehicle 12 reaches the position of the obstacle 14.

In the first embodiment, as shown in FIG. 4, the arrival predicting unit 38 determines whether the vehicle 12 and the obstacle 14 have the deceleration d ₀ when determining whether the vehicle 12 reaches the position of the obstacle 14. In order to consider the size, the vehicle 12 is moved in the X-axis direction (L _F + L _R ) (L _F from the center of gravity of the vehicle 12 to the front end and L _R to the rear end) based on the detected information. The obstacle 14 is regarded as a circle having a radius r, and a rectangle having a width B in the Y-axis direction. Here, in Example 1, since it is assumed that the obstacle 14 is a pedestrian, the obstacle 14 is regarded as a circle having a radius r. The size, shape, and the like are appropriately set based on the estimation of the attributes. When the obstacle 14 is stationary, the position P ₀ (x _p (t ₀ ), y _p (t ₀ )) of the obstacle 14 at the current time T ₀ instead of the predicted obstacle movement locus = It is determined whether or not the vehicle 12 reaches the position of the obstacle 14 using (x _p0 , y _p0 ).

  The frictional force limit setting means 39 (see FIG. 2) is the limit of the frictional force of the four tires 33 of the vehicle 12, that is, the maximum grip force that each tire 33 of the vehicle 12 can exhibit (hereinafter, the maximum gripping force). Based on the above, the limit range of the resultant force of the acceleration force, deceleration force and lateral force generated in the vehicle 12 is set. Generally, when the road surface friction coefficient is μ and the vertical load applied to each tire 33 is W, the frictional force of each tire 33 does not become larger than (μW). Therefore, if it is assumed that the vertical loads applied to the tires 33 are the same, the constraint that the braking force D and the lateral force F generated in the vehicle 12 must satisfy the inequality represented by the following equation (9) for each tire 33: (See FIG. 5).

(D / 4) ² + (F / 4) ² ≦ (μW) ² (9)
In equation (9), the first term on the left side is set to (D / 4) ² using the braking force D, but the variable represented by D is an acceleration force and a deceleration force, that is, for the vehicle 12. It consists of driving force and braking force. In the first embodiment, when the avoidance operation amount is calculated, only the case where the braking force is applied to the vehicle 12 is assumed. Therefore, the braking force D is used as the first term on the left side of the equation (9). A circle drawn by the equation (9) (see FIG. 5) is a tire friction circle, and when the condition of the equation (9) is satisfied, that is, at each action point in the tire friction circle, each tire 33 is traveling. It shows a state of gripping with the road surface, and shows that each tire 33 exerts the maximum grip force at the point of action on the circumference of the tire friction circle.

  The vertical load W applied to each tire 33 is different and moreover, strictly speaking, it is a force that changes depending on the motion state of the vehicle 12, but the difference between the tires 33 and the dependency on the vehicle motion are ignored. For example, when the weight of the vehicle 12 is m and the gravitational acceleration is g, the vertical load W can be approximated by the following equation (10).

W = mg / 4 (10)
Here, the road surface friction coefficient μ can be appropriately set within a range that does not exceed the road surface friction coefficient of the road surface assumed to actually travel. Further, it is conceivable that the road surface friction coefficient μ is set within the performance range of the braking motion control means 34 of the vehicle motion control means 15 used in the vehicle 12. In this case, for example, when the maximum control force in the specification of the braking motion control means 34 is D _max , the following equation (11) may be set.

μ ≦ D _max / 4W (11)
Further, the road surface friction coefficient μ may be calculated based on the road 13 on which the vehicle 12 is actually traveling. In this case, many known techniques for estimating from the image of the road 13 or the motion state of the vehicle 12 are known, and can be calculated using a known road friction coefficient estimation technique.

Avoidance target position calculating means 40, when the vehicle 12 by the predicted arrival means 38 is determined to reach the position of the obstacle 14, in the area that may vehicle 12 reaches the predicted time T _A, the vehicle 12 is obstacle 14 calculating an avoidance target position G _a can be avoided from reaching the location. Avoidance target position G _A, since the vehicle 12 to follow the predicted deceleration movement locus is calculated on the assumption that it reaches the position of the obstacle 14, in the first embodiment, the turning force to the vehicle 12 to follow the predicted deceleration movement locus In addition, it is set to a reachable area. As described above, in the friction force limit setting means 39, the limit range of the combined force of the braking force D and the lateral force F generated in the vehicle 12 is defined by the equation (9), and this equation (9) is expressed on the coordinates. What is shown is the tire friction circle shown in FIG. 5, and the circumference of this circle is the limit range of the combined force of the braking force D and the lateral force F. From this equation (9), the range of the lateral force F that can be generated in the vehicle 12 when the vehicle 12 is decelerated at the deceleration d ₀ can be expressed by the following equations (12) and (13).

−F _max (d ₀ ) ≦ F ≦ F _max (d ₀ ) (12)

ここで、操舵されていない状態において車両１２が減速度ｄ_０で減速している場合、各タイヤ３３が発揮する制動力は（ｍｄ_０／４）となり、この制動力による作用点が図５のタイヤ摩擦円上でＥ_１となる。タイヤ摩擦円が示す合成力の限界範囲から、作用点Ｅ_１にある車両１２には、作用点Ｅ_１から横軸方向すなわち横力方向に沿う線と円との交点Ｅ_Ｌおよび交点Ｅ_Ｒで規定される線分Ｅ_ＬＥ_Ｒ上にある任意の作用点に相当する横力を作用させることができることを読み取ることができる。

Here, when the vehicle 12 is decelerating in a deceleration d ₀ in a state of not being steered, the braking force each tire 33 is exerted (md _0/4), and the point of action by the braking force in FIG. 5 the _{E 1} in the tire friction circle. The limitation range of the resultant force indicated by the tire friction circle, the vehicle 12 in the point E _1, at the intersection E _L and the intersection E _R of a line and a circle along the horizontal axis or transverse force direction from the point E ₁ It can be read that a lateral force corresponding to an arbitrary action point on the defined line segment E _L E _R can be applied.

When a lateral force to the left corresponding to the action point E _L is applied to the vehicle 12 that is decelerated at the deceleration d ₀ and a lateral force to the right corresponding to the action point E _R is applied, When both the assumed that uniformly accelerated motion in the lateral force F _max (d _0), Y coordinates of the position where the vehicle 12 reaches the predicted time T _a can be expressed by the following equation (14).

_{y (T A) = ± F} max (d 0) * T A 2/2 (14)
The (14) and FIG. 6 that the arrival position schematically showing a vehicle 12 which is calculated from the equation, a reaching point A _R corresponding to the point E _R, reached that corresponds to the point E _L The point is _AL . The position A _1, when the vehicle 12 is in a state of not being steered is decelerated at the deceleration d _0, which is the position where the vehicle 12 to predict the time T _A is expected to arrive. From this, when the action point on the line segment E _L E _R is used, the vehicle 12 reaches the line segment A _R A _L , and therefore the avoidance target position G _A is the line segment A _R A _L is set within the range.

Further, in the first embodiment, the avoidance target position calculation unit 40 is within the range of the line segment A _R A _L and does not reach the position of the obstacle 14 based on the arrival state calculated by the arrival prediction unit 38. from sets the avoidance target position G _a to the position that can be reached by the smallest amount of movement (steering amount).

For example, as shown in the enlarged view of FIG. 4, the calculated arrival state is that the obstacle 14 is shifted from the center of the vehicle 12 to the right by b at the front end portion of the vehicle 12 when viewed in the width direction of the vehicle 12. Is assumed to have reached the position of a circle of radius r indicating In this case, in order to avoid reaching the position of the obstacle 14 at the predicted time T _A , the vehicle 12 has (r−b + B / on the left side with respect to the position A ₁ (Y coordinate is 0). 2) It is necessary to move more than or to the right (r + b + B / 2) or more. Furthermore, when the obstacle 14 Considering that is moving to the right, to avoid the position A ₁ to the right, in addition to the tip portion of the vehicle 12 does not reach the position of the obstacle 14, the vehicle 12 is a line segment It is required that the vehicle 12 does not reach the position of the obstacle 14 while the vehicle 12 moves forward by the length of the vehicle 12 (L _F + L _R ) from the position reached on A _R A _L. Therefore, to avoid the position _{A 1} to the right, it is necessary to add a movement amount of the obstacle 14 is advanced during the advance by the amount of movement of the (r + b + B / 2 ), the vehicle 12 _(L F + L _R) . Therefore, avoidance target position calculating means 40, from the viewpoint of the amount of movement is reduced, it sets the avoidance target position G _A from the position A ₁ to the left. In Example 1, the avoidance target position _{G A, (r-b +} B / 2) by a distance obtained by adding the appropriate avoidance margin distances [Delta] y, set from the position A ₁ to the position displaced to the left. The coordinates (x _G , y _G ) of the avoidance target position G _A (see FIG. 7) can be expressed by the following expressions (15) and (16).

_{x G = x P (t 0} ) -L F (15)
y _G = − (r−b + Δy + B / 2) (16)
Avoidance operation quantity calculating unit 41 calculates the avoidance operation amount of the vehicle 12 required for the vehicle 12 reaches the avoidance target position G _A.

In the first embodiment, the avoidance operation amount calculation unit 41 first considers a lateral movement, that is, a movement in the Y-axis direction that is the width direction of the road 13. When it is assumed that the movement is performed with constant acceleration so as to reach the Y coordinate y _G of the avoidance target position G _{A at} the predicted time T _A , the necessary lateral acceleration a _y can be expressed by the following equation (17).

^{_{a y = 2y G / T A}} 2 (17)
It is necessary to calculate the front wheel rudder angle that realizes the lateral acceleration _ay . In general, a relational expression such as the following expression (18) can be assumed between the response of the lateral acceleration to the front wheel steering angle input.

この（１８）式において動特性の部分を表すＱ（s、v）を１とみなし、定常特性の関係だけを抜き出した近似式を次式（１９）に示す。

In this equation (18), Q (s, v) representing the dynamic characteristic portion is regarded as 1, and an approximate expression in which only the relationship of the steady characteristic is extracted is shown in the following equation (19).

以上のような伝達特性を事前に同定しておけば、（１７）式の目標横加速度ａ_ｙ ^＊を漸近的に達成するための前輪舵角目標値δ^＊が次式（２０）により算出することができる。

If the transfer characteristics as described above are identified in advance, the front wheel steering angle target value δ ^* for asymptotically achieving the target lateral acceleration a _y ^* of equation (17) is calculated by the following equation (20). be able to.

実際には、伝達関数Ｑ（s、v）で表現される応答遅れが存在するため、直ちに目標横加速度ａ_ｙが得られるわけではないが、応答遅れに見合うように回避余裕距離Δ_ｙを設定しておけば、車両１２の障害物１４の回避という目的は十分に達成することができる。

Actually, since there is a response delay expressed by the transfer function Q (s, v), the target lateral acceleration a _y is not always obtained, but the avoidance margin distance Δ _y is set to match the response delay. If so, the object of avoiding the obstacle 14 of the vehicle 12 can be sufficiently achieved.

  Next, consider vertical motion, that is, motion in the X-axis direction, which is the direction of the road 13. Regarding the deceleration movement of the vehicle 12, a brake pressure value p applied to each brake 26 from the hydraulic control system 25 and a deceleration as a behavior appearing on the vehicle 12 when each brake 26 is operated by the brake pressure value p. By measuring the relationship with d (in this case, the deceleration d is a steady value) in advance, the following relational expression (21) is obtained.

そこで、減速度ｄ_０に対応するブレーキ圧の値ｐ^＊を、関数Ｒの逆関数Ｒ^−１を用いて、次式（２２）で算出することができる。

Therefore, the brake pressure value p ^* corresponding to the deceleration d ₀ can be calculated by the following equation (22) using the inverse function R ⁻¹ of the function R.

次に、本発明に係る回避操作算出装置１０による障害物１４を回避するための運転操作量の算出の工程を図８に示すフローチャート（これを処理Ａとする。）に沿って説明する。このフローチャートは、図３に示す場面を想定している。図３は、道路１３を自車両である車両１２が走行しており、車両１２の前方の左側から歩行者（障害物１４）が道路１３に飛び出してきた場面を表している。なお、このフローチャートは、車両１２が走行している間、繰り返し行なわれるものである。

Next, the process of calculating the driving operation amount for avoiding the obstacle 14 by the avoidance operation calculating device 10 according to the present invention will be described with reference to the flowchart shown in FIG. This flowchart assumes the scene shown in FIG. FIG. 3 shows a scene in which the vehicle 12, which is the host vehicle, travels on the road 13 and a pedestrian (obstacle 14) jumps out of the road 13 from the left side in front of the vehicle 12. This flowchart is repeatedly performed while the vehicle 12 is traveling.

  The reachability determination means 35 recognizes the road 13 on which the vehicle 12 is traveling based on the information processed by the own vehicle information processing unit 28 and the obstacle information processing unit 29, and the obstacle 14 exists on the road 13. If the obstacle 14 exists, the process proceeds to step S2, and if the obstacle 14 does not exist, the confirmation is continued (step S1). At this time, information processed by the vehicle information processing unit 28 and the obstacle information processing unit 29 based on the signals output from the sensors 17 to 19 is stored in the memory 31, and the information in the memory 31 is reached. Reading by the possibility determination means 35 and the avoidance operation amount generation means 30 is enabled.

  When the reachability determination unit 35 detects that an obstacle 14 (pedestrian in the first embodiment) exists on the road 13 based on the information processed by the acquired information processing unit 27, the avoidance of the obstacle 14 is avoided. It is determined whether or not it is necessary to calculate the avoidance operation amount for (step S2). When it is determined that it is necessary to calculate the avoidance operation amount, a coordinate system is set (see FIG. 3), and the information stored in the memory 31 and the information processed by the acquisition information processing means 27 are set to the set coordinate system. If necessary (see FIG. 3), the process proceeds to step S3. When it is determined that it is not necessary to calculate the avoidance operation amount, the flowchart is ended.

When it is determined that the avoidance operation amount needs to be calculated, the own vehicle movement trajectory calculation unit 36 calculates a predicted deceleration movement trajectory, and the obstacle movement trajectory prediction unit 37 calculates a predicted obstacle movement trajectory ( Step S3). The obstacle movement trajectory predicting unit 37 does not calculate the predicted obstacle movement trajectory when it is determined that the obstacle 14 is stationary. The own vehicle movement locus calculating means 36 sets the deceleration d ₀ based on a general tire friction circle or a tire friction circle in the previous flowchart.

The arrival prediction means 38 determines whether or not the vehicle 12 that follows the predicted deceleration movement locus reaches the position of the obstacle 14 that follows the predicted obstacle movement locus (step S4). When it determines with reaching | attaining, it progresses to step S5 in order to calculate an avoidance operation amount. When it determines with not reaching | attaining, it progresses to step S8 in order to make the vehicle 12 perform an estimated deceleration movement locus. When the obstacle 14 is stationary, the arrival determination is performed using the position (x _p0 , y _p0 ) of the obstacle 14 instead of the predicted obstacle movement locus.

  The frictional force limit setting means 39 sets a limit range (see FIG. 5) of the combined force of acceleration force, deceleration force and lateral force that can be generated in the vehicle 12 (step S5).

The avoidance target position calculation means 40 calculates the avoidance target position G _A (see FIG. 7) (step S6).

Avoidance operation quantity calculating unit 41, avoiding the operation amount for the vehicle 12 reaches the avoidance target position G _A (see FIG. 7.), I.e., calculates a value p ^* of the front wheel steering angle target value [delta] ^* and the brake pressure ( Step S7).

In step S4, when the vehicle 12 to follow the predicted deceleration movement trajectory is determined not to reach the position of the obstacle 14, the avoidance operation amount calculating means 41, realized deceleration d ₀ which became the basis for the prediction deceleration movement trajectory an operation amount and avoidance operation amount, calculates a value p ^* of the brake pressure to achieve the deceleration d ₀ (step S8).

  The avoidance operation amount calculation means 41 transmits the calculated avoidance operation amount to the buffer memory 42, and transmits it to the steering angle servo controller 23 and the brake controller 24 via the buffer memory 42 (step S9).

  As shown in this flowchart, the avoidance operation calculation device 10 calculates an avoidance operation amount that can avoid the obstacle 14 with a small operation amount. In the first embodiment, the avoidance operation calculation device 10 constitutes a part of the avoidance control device 11, and the steering and braking operation corresponding to each optimum driving operation amount is executed by the vehicle motion control means 15 as the other part. .

FIG. 7 shows a movement trajectory of the vehicle 12 based on the avoidance operation amount calculated for avoiding the arrival of the obstacle 14. In FIG. 7, the vehicle 12 (G _A ) and the obstacle 14 (P ₁ ) at the predicted time T _A are indicated by solid lines, and the vehicle 12 (A ₀ at the time when the obstacle 14 is detected (evaluation start time T _S ). ) and, with the obstacle 14 (P _0), it shows the movement locus of the vehicle 12 and the obstacle 14 up to the predicted time T _a by the two-dot chain line.

  As shown in FIG. 7, the vehicle 12 can avoid reaching the position of the obstacle 14 by the avoidance control device 11. At this time, as shown in FIGS. 5 and 6, the avoidance operation amount is calculated within the limit range of the acceleration force, deceleration force and lateral force that can be generated in the vehicle 12. Thus, the obstacle 14 can be avoided accurately. In other words, the avoidance operation amount is calculated by actively excluding the range in which the combined force of the acceleration force, the deceleration force and the lateral force generated in the vehicle 12 exceeds the total grip force of each tire 33 supporting the vehicle 12. Therefore, the avoidance movement trajectory according to the avoidance operation amount can be reliably realized, and the arrival of the obstacle 14 at the position can be avoided.

  Therefore, in the avoidance operation calculation device 10 according to the present invention, the avoidance operation amount is calculated within the limit range of the acceleration force, the deceleration force and the lateral force that can be generated in the vehicle 12, so that the vehicle 12 is stabilized. The avoidance operation amount that can avoid reaching the position of the obstacle 14 can be calculated from the behavior.

  A second embodiment of the avoidance operation calculation device 10 and the avoidance control device 11 including the avoidance operation calculation device 10 according to the present invention will be described with reference to FIGS. The second embodiment is an example in which the method of calculating the avoidance operation amount in the avoidance operation amount calculation means 41 in the avoidance operation calculation device 10 and the avoidance control device 11 including the same is different from that in the first embodiment. For this reason, the avoidance operation calculation device 10 of the second embodiment and the avoidance control device 11 (see FIG. 2) including the same are basically the same as the avoidance operation calculation device 10 of the first embodiment and the avoidance control device 11 including the same. The detailed description of the configuration is omitted, and the detailed description of the same operation is also omitted.

  In the first embodiment, when the avoidance operation amount is calculated by the avoidance operation amount calculation means 41, the avoidance operation amount is calculated by a simple method without considering the detailed dynamics of the vehicle motion control and the response delay of the vehicle control system. Showed how to do. The method shown in the first embodiment has an advantage that it can be realized by a simple calculation rule. In the second embodiment, for example, it is assumed that a control error cannot be ignored in order to realize reliable avoidance in a scene where there is little allowance for time and distance to avoid and high-precision vehicle motion control is required. The method of calculating the avoidance operation amount in a form that explicitly considers the dynamics of the vehicle motion and the time delay of the control system will be described.

In the second embodiment, processing similar to the flowchart of the first embodiment (see FIG. 8) is performed except for the method of calculating the avoidance operation amount by the avoidance operation amount calculating means 41 (step S7). Therefore, in the second embodiment, the scene shown in FIG. 3 is assumed as in the first embodiment, and the target avoidance position G _A (x _G , y _G ) similar to that in the first embodiment (see FIG. 6). )) Is set.

  The avoidance operation amount calculation means 41 introduces a vehicle model as a model of the vehicle motion and control system in order to calculate the avoidance operation amount. Although various models can be used as the vehicle motion model, the following vehicle model is introduced in the second embodiment.

  The vehicle model is described by differential equations (23) to (30) below. Note that x ′ represents time differentiation of x.

x ′ = v cos (β + θ) (23)
y ′ = vsin (β + θ) (24)
θ ′ = γ (25)
v ′ = d (26)

ここで、前述したように、θは車両１２の姿勢角（ヨー角）、βはすべり角、ｖは走行速度、γはヨーレートである。また、ｍは車両１２の重量、Ｉは車両１２に生じる車両ヨー慣性モーメント、ｌ_ｆは車両重心から前輪軸までの距離、ｌ_ｒは車両重心から後輪軸までの距離を表す。Ｙ_ｆは２つの前輪のタイヤ横力を表し、かつＹ_ｒは２つの後輪のタイヤ横力を表す関数であり、それぞれ前輪すべり角β_ｆ、後輪すべり角β_ｒの関数であると仮定している。（２９）、（３０）式は、それぞれブレーキコントローラ２４および操舵角サーボコントローラ２３に目標指令値（回避操作量）を与えてから制御量が目標指令値に到達するまでの時間遅れを表現しており、Ｔ_Ｂ、Ｔ_Ｓはそれぞれの制御系の応答時定数である。ここで、前輪舵角をδとすると、前輪すべり角β_ｆ、後輪すべり角β_ｒは次式（３１）、（３２）で表すことができる。

Here, as described above, θ is the attitude angle (yaw angle) of the vehicle 12, β is the slip angle, v is the traveling speed, and γ is the yaw rate. Further, m is the distance of the weight of the vehicle 12, I is the vehicle yaw inertia moment generated in the vehicle 12, l _f from the center of gravity of the vehicle to the front axle, l _r is the distance to the rear axle from the center of gravity of the vehicle. Y _f represents the tire lateral force of the two front wheels, and Y _r is a function representing the tire lateral force of the two rear wheels, and is assumed to be a function of the front wheel slip angle β _f and the rear wheel slip angle β _r , respectively. is doing. Expressions (29) and (30) express time delays from when the target command value (avoidance operation amount) is given to the brake controller 24 and the steering angle servo controller 23 until the control amount reaches the target command value, respectively. T _B and T _S are response time constants of the respective control systems. Here, when the front wheel rudder angle is δ, the front wheel slip angle β _f and the rear wheel slip angle β _r can be expressed by the following equations (31) and (32).

β _f = β + l _f γ / v−δ (31)
β _r = β-l _r γ / v (32)
The tire lateral forces Y _f and Y _r can be expressed using a function that reflects the slip angle dependency of the tire friction force and the constraint (limit range) of the tire friction circle shown in FIG. Many models have been proposed as models that approximate the characteristics of the tire lateral force. In the second embodiment, a simplified tire model represented by the following equations (33) and (34) is considered.

  Summarizing the equations introduced above, the vehicle model is summarized into a nonlinear model represented by the following equation (35).

車両１２を精度良く回避目標位置まで到達させる回避操作量を算出するために、到達予測手段３８により設定された評価開始時刻Ｔ_Ｓから、車両１２が回避目標位置Ｇ_Ａ（ｘ_Ｇ、ｙ_Ｇ）に到達する予測時刻Ｔ_Ａに至るまでの入力ベクトルｕの時系列を考え、予測時刻Ｔ_Ａにおいて回避目標位置Ｇ_Ａ（ｘ_Ｇ、ｙ_Ｇ）になるべく近い位置に到達するという意味で最適なｕを算出する最適制御問題を考える。最適制御問題において評価関数は一般に、次式（３８）で定義することができる。

In order to calculate the avoidance operation amount for causing the vehicle 12 to reach the avoidance target position with high accuracy, the vehicle 12 detects the avoidance target position G _A (x _G , y _G ) from the evaluation start time T _S set by the arrival prediction means 38. Considering the time series of the input vector u up to the predicted time T _A to reach, the optimum u in the sense that the target position G _A (x _G , y _G ) is reached as close as possible at the predicted time T _A Consider the optimal control problem to calculate In the optimal control problem, the evaluation function can be generally defined by the following equation (38).

ただし、ψは、回避目標位置Ｇ_Ａ（ｘ_Ｇ、ｙ_Ｇ）を基準とする予測時刻Ｔ_Ａにおける車両１２の位置の望ましさを評価する評価式であり、Ｌは、評価開始時刻Ｔ_Ｓから予測時刻Ｔ_Ａまでの間の各時刻における車両１２の減速操作量および操舵量からなる回避操作量の小ささの望ましさを評価する評価式であり、τは、評価開始時刻Ｔ_Ｓから予測時刻Ｔ_Ａまで変化する積分変数である。評価式ψは次式（３９）で、かつ評価式Ｌは次式（４０）で表すことができる。

However, ψ is an evaluation formula that evaluates the desirability of the position of the vehicle 12 at the predicted time T _{A based on} the avoidance target position G _A (x _G , y _G ), and L is determined from the evaluation start time T _S. a evaluation formula for evaluating the deceleration operation amount and the desirability of avoiding manipulation of small consisting steering amount of the vehicle 12 at each time until the predicted time T _a, tau is estimated time from the evaluation starting time T _S it is an integral variable to change to T _a. The evaluation formula ψ can be expressed by the following formula (39), and the evaluation formula L can be expressed by the following formula (40).

ただし、Ｗ_ｘ、Ｗ_ｙ、Ｗ_ｐ、Ｗ_δは各評価項に対する重みパラメータである。

However, W _x , W _y , W _p , W _δ are weight parameters for each evaluation term.

  In general, an algorithm for solving an optimal control problem for obtaining a control input u of equation (37) that minimizes the value of the evaluation function of equation (38) for a system described by equation (35) (optimization algorithm) As such, several known techniques are known, and the optimal control input u can be calculated by using such known techniques.

In some of the optimization algorithms, it is necessary to set an appropriate initial value prior to the calculation of the optimal solution, and the calculation time for obtaining the optimal solution may change depending on the setting of the initial value. In order to obtain the solution efficiently, it is desirable to set an initial value as close to the optimum solution as possible. Similarly to the first embodiment, the avoidance target position calculation unit 40 according to the second embodiment is not separated from the position A _{1 as} much as possible with reference to the position A ₁ that is reached by the deceleration operation (predicted deceleration movement trajectory) at the deceleration d _0. Since the avoidance target position G _A (x _G , y _G ) is set at the place, the optimum avoidance operation amount to be obtained is the operation amount at which the vehicle 12 reaches the position A ₁ at the predicted time T _A , that is, steering. it is expected close to the operation amount for decelerating the vehicle 12 in deceleration d ₀ in not even state is. Operation amount vehicle 12 reaches the position A ₁ in this prediction time T _A can be expressed by the following equation (41).

このため、（４１）式を最適化計算の初期値とすることが、効率的に解を求めるための有効な手段であると考えられる。

For this reason, using the equation (41) as an initial value for the optimization calculation is considered to be an effective means for efficiently obtaining a solution.

  In the case of the second embodiment, the optimum avoidance operation amount includes the deceleration operation amount controlled by the brake pressure value p and the steering amount controlled by the front wheel steering angle δ. Is calculated. In calculating the actual optimum avoidance operation amount, the evaluation section is divided by an appropriate number of steps N (predetermined intervals), and the optimum avoidance operation amount value at each discretization step is calculated. An example of a result (avoidance operation amount) obtained by solving such an optimal control problem is shown in FIG. By using a model that takes into account the response delay in the vehicle model, a time series of the operation amount command value (avoidance operation amount) that calculates a command value larger than the actual operation amount and compensates for the response delay is automatically calculated. ing.

FIG. 10A is a graph showing the relationship between the deceleration of the vehicle 12 and time, and occurs in the vehicle 12 when the vehicle 12 is controlled with an ideal deceleration operation amount calculated when the response delay is not taken into consideration. it is indicative of expected deceleration d _c anticipated by the solid line, shows a deceleration command value d _s is the deceleration occurring on the vehicle 12 when controlling the vehicle 12 by a broken line in the calculated deceleration operation amount. Deceleration command value d _s is the evaluation start time T _S, the large deceleration d _smax than the deceleration operation amount of ideal to accommodate a response delay which is a deceleration command value, the delay time T ₁ after the expected It is equal deceleration command value d _s to deceleration d _c.

FIG. 10B is a graph showing the relationship between the steering amount of the vehicle 12 and time. When the vehicle 12 is controlled with the ideal steering amount calculated when the response delay is not taken into consideration, the vehicle 12 is shown. An expected steering amount δ _c that is expected to be generated is indicated by a solid line, and a steering amount command value δ _s that is a steering amount generated in the vehicle 12 when the vehicle 12 is controlled by the calculated steering amount is indicated by a broken line. The steering amount command value δ _s has a steering amount command value δ _smax that is larger than the ideal steering amount in order to cope with a response delay at the evaluation start time T _S , and the steering amount after the delay time T ₁ . There was corresponding to the expected steering amount [delta] _c being reduced, the time T _2, after being equal to the expected steering amount [delta] _c steering amount command value [delta] _s.

The vehicle motion control means 15 is activated when time series data of optimum avoidance operation amounts (N brake pressure values p ^* and front wheel steering angle δ ^* ) is stored in the buffer memory 42. The stored data is sequentially read in the time series of the optimum driving operation amount in a time period of T / N, and the brake controller 24 performs hydraulic pressure according to the brake pressure value p ^* which is the optimum deceleration operation amount read. The steering control means 32 performs servo control of the front wheel steering angle by controlling the control system 25 and setting the read front steering angle δ ^* which is the optimum steering amount as the target steering angle. Vehicle motion control unit 15 reaches the predicted time T _A, the avoidance operation quantity stored in the buffer memory 42 is read all ends the execution of the avoidance control, the vehicle 12 together with the end of the driver driving operation Return to the normal running state.

  In the avoidance operation calculation device 10 and the avoidance control device 11 according to the second embodiment, the avoidance operation amount is calculated in consideration of the dynamics of the vehicle motion and the time delay of the control system. ) Can be reliably avoided even in a scene that requires high-precision vehicle motion control.

  A third embodiment of the avoidance operation calculation device 10 and the avoidance control device 11 including the avoidance operation calculation device 10 according to the present invention will be described with reference to FIGS. 11 to 14. The third embodiment has the same configuration as the avoidance operation calculation device 10 of the second embodiment and the avoidance control device 11 including the same, and the avoidance operation amount calculation method in the avoidance operation amount calculation means 41 is the same as that of the second embodiment. It is. For this reason, detailed description of the configuration of the avoidance operation calculation device 10 and the avoidance control device 11 including the same is omitted, and detailed description of equivalent operations is also omitted.

The avoidance operation calculation device 10 and the avoidance control device 11 including the same set a certain control time, calculate the predicted obstacle movement trajectory of the obstacle 140 for each control time, and calculate the predicted failure It is determined at every control time whether or not the vehicle 120 that follows the calculated avoidance operation amount reaches the position of the obstacle 140 that follows the object movement trajectory, and if necessary, the avoidance operation amount is recalculated. is there. This obstacle 140 (see FIG. 11.) Is a different behavior than the predicted obstacle movement locus calculated by the obstacle movement locus prediction unit 37 in the evaluation start time T _S, and after the evaluation start time T _S Even in this case, the avoidance operation amount that can cope with the change in the behavior of the obstacle 140 can be calculated.

In the third embodiment, as shown in FIG. 11, when the vehicle 120 moves from the position A ₀ to the position A ₀₁ until the current time t ₀ , the obstacle 140 (pedestrian) is moved from the position P ₀ to the position P _0. The scene is assumed to move to P ₀₁ and then stop moving.

A flow chart of vehicle control executed by the microprocessor 20 in the third embodiment is shown in FIG. The process of the flowchart of FIG. 12 is premised on being repeatedly executed at regular control times. In the current time t ₀ the flowchart of FIG. 12 refers to a time that initiated the process in the flowchart.

The avoidance operation amount calculation means 41 determines whether or not arrival avoidance control is being executed (step S1). As the determination method, for example, avoidance operation amount calculation unit 41 checks the buffer memory 42, the current time t ₀ corresponding command value after the buffer memory 42 (avoidance operation amount) reaches avoidance control if it is stored It is possible to determine that the arrival avoidance control is not executed otherwise. If the arrival avoidance control is being executed, the process proceeds to step S4. If not, the process proceeds to step S2.

When the arrival avoidance control is not being executed, the avoidance operation amount generation means 30 and the reachability determination means 35 calculate the avoidance operation amount along the process A (the flowchart shown in FIG. 8) (step S2). The avoidance operation amount generation means 30 and the reachability determination means 35 calculate the avoidance operation amount based on the own vehicle information of the vehicle 120 at the current time t _0, the information of the obstacle 140, and the predicted obstacle movement locus based on the information. Try again. In the third embodiment, when the calculation is re-executed, the current time t ₀ is set as the evaluation start time T _S, and the time series of the avoidance operation amount from the evaluation start time T _S to the predicted time T _A as in the second embodiment. Is calculated.

  The avoidance operation amount calculation means 41 determines whether or not an avoidance operation amount has been calculated in the process A of step S2 (step S3). As this determination method, when it is determined that it is not necessary to calculate the avoidance operation amount in the process of calculating the avoidance operation amount along the process A in step S2 (reachability determination means in step S2 of the flowchart of FIG. 8). 35)), it can be determined that the avoidance operation amount has not been calculated, otherwise it can be determined that the avoidance operation amount has been calculated. If the avoidance operation amount has not been calculated, the flowchart is terminated. If the avoidance operation amount has been calculated, the process proceeds to step S7.

If it is determined in step S1 that the arrival avoidance control is being executed, the avoidance operation amount calculation unit 41 calculates a prediction avoidance movement locus when the vehicle 120 has followed the avoidance operation amount, and the obstacle movement locus prediction means. 37 calculates a predicted obstacle movement locus based on information of the obstacle 140 at the current time _{t 0} (step S4).

The prediction avoidance movement trajectory of the vehicle 120 can be calculated as follows, for example. Reaching avoidance control in the evaluation start time T _S in reaching avoidance control is executed is started, and that avoidance operation amount until the predicted time _{T A u (t) (T} S ≦ t ≦ T A) is generated To do. It is assumed that the arrival avoidance control is executed according to the generated u (t), and the state vector of the vehicle 120 defined by the equation (36) is changed to x (t ₀ ) at the current time t ₀ . At this time, the vehicle motion trajectory _{x (t) (t 0 ≦} t ≦ T A) up to the predicted time _{T A} is, x _{(t 0)} time to predict the differential equation as an initial value (35) in the forward direction T It can be calculated by integrating up to _A. When the obstacle 140 is moving, the prediction avoidance movement trajectory can be calculated based on the information on the obstacle 140 from the evaluation start time T _S to the current time t ₀ as in the first embodiment. it can.

The predicted obstacle movement trajectory of the obstacle 140 is that the obstacle 140 reaches the position P ₀₁ {x _p (t ₀ ), y _p (t ₀ )} at the current time t ₀ , and the movement at the position P ₀₁ if stopped, until the predicted time T _a, the obstacle 140 is much becomes the prediction that continues remain in position P ₀₁ is obtained, can be calculated on the basis of such predictions.

  The arrival prediction unit 38 determines whether or not the vehicle 120 reaches the position of the obstacle 140 when the current arrival avoidance control is continuously executed based on the predicted avoidance movement trajectory and the predicted obstacle movement trajectory calculated in step S4. Is determined (step S5). If it is determined that it does not reach, the process proceeds to step S7, and if it is determined that it reaches (see FIG. 11), the process proceeds to step S6.

  If it is determined that it reaches, the avoidance operation amount calculation means 41 clears all the command values (avoidance operation amount) stored in the buffer memory 42, and proceeds to Step 2 (Step S6).

  If it is determined that it does not reach, the avoidance operation amount calculation means 41 transmits the calculated avoidance operation amount to the buffer memory 42 and transmits it to the steering angle servo controller 23 and the brake controller 24 via the buffer memory 42 (step). S7).

Even when the avoidance operation is performed again at step S2 (when the process proceeds from step S6 to step S2), the content of the process is the same as that shown in the second embodiment. For example, as shown in FIG. 13, when the vehicle 120 moves from the position A ₀ (see FIG. 11) at the evaluation start time T _S to the position A _{01 at} the current time t ₀ , the vehicle 120 at the position A ₀₁ the vehicle state as the basis for, based on the predicted arrival position a ₁₁ when decelerated at a constant deceleration d _0, the predicted arrival point a _L0 corresponding to the point on the circumference of the tire friction circle (see Fig. 5.) , A _R0 is calculated. As shown in FIG. 13, in Example 3, since it is predicted that both the position A ₁₁ and the position A _L0 cannot be reached, the avoidance target position is closer to the right position A _R0 from the position A _11. G _A3 (see FIG. 14) is set. When the avoidance target position reset to G _A3, avoidance operation amount calculated at the current time t ₀ is a manipulated variable that follows a vehicle moving path as shown in FIG. 14. With the above configuration, even when the obstacle 140 suddenly changes its behavior, an avoidance operation amount corresponding to the behavior change can be obtained. In FIG. 14, the vehicle 120 (G _A3 ) and the obstacle 140 (P ₀₁ ) at the predicted time T _A are indicated by solid lines, and the vehicle 120 (A ₀ ) at the initially set evaluation start time T _S and the calculation A two-dot chain line shows the vehicle 120 (A ₀₁ ) at the current time t ₀ when the re-start is started and the movement locus of the vehicle 120 up to the predicted time T _A.

The avoidance control device 11 avoids including operation calculation device 10 and the same of Example 3, when running avoidance control, there in case the behavior of the obstacle 140 has changed from that predicted by the evaluation start time T _S However, the avoidance operation amount corresponding to the change in the behavior of the obstacle 140 can be calculated. For this reason, for example, when the vehicle 120 moves from the position A ₀ to the position A ₀₁ , the obstacle 140 (pedestrian) moves from the position P ₀ to the position P ₀₁ and then stops moving. However, as shown in FIG. 14, it is possible to calculate and execute the avoidance operation amount that does not reach the position of the obstacle 140.

  Example 4 of the avoidance operation calculation device 10 and the avoidance control device 11 including the avoidance operation calculation device 10 according to the present invention will be described with reference to FIGS. 15 to 17.

  In the fourth embodiment of the present invention, the avoidance operation calculating device 10 of the first to third embodiments and the avoidance control device 11 including the avoidance operation calculating device 10 are set by the avoidance target position calculating means 40 of the avoidance operation calculating device 10. This is an example of a different method.

  The avoidance operation calculating device 10 of the fourth embodiment and the avoidance control device 11 including the avoidance operation calculating device 11 (see FIG. 2) basically have the same configuration as the avoidance operation calculating device 10 of the first embodiment and the avoidance control device 11 including the same. Yes, detailed description of the same parts will be omitted. The calculation of the avoidance operation amount is the same as that in the third embodiment, and detailed description of the same operation is omitted.

In the fourth embodiment, the scene shown in FIG. 3 similar to the first and second embodiments is assumed. In the fourth embodiment, when calculating the avoidance target position G _A4 (see FIGS. 16 and 17), as in the first to third embodiments, deceleration is performed from the limit range indicated by the tire friction circle (see FIG. 5). When the deceleration is changed as shown in FIG. 15 instead of calculating the avoidance target position G _A (see FIG. 7) based on the action point in the line segment E _L E _R fixed at d ₀ . A configuration for searching for an appropriate avoidance target position _GA4 is also shown.

Further, in the fourth embodiment, in consideration of the obstacle 1400 approaching from the left direction, the setting range of the avoidance target position _GA4 is limited to avoiding in the right direction. In this example, the prediction is made when the vehicle 1200 existing at the position A ₀ at the evaluation start time T _S operates with the following operation amounts (a) to (d) corresponding to the limit range of the application point of the tire friction force. _A region surrounded by four points that are expected to reach at time TA is considered.
(A) Deceleration d ₀ , lateral force 0
(B) Deceleration d ₀ , right lateral force Maximum (c) Deceleration 0, lateral force 0
(D) deceleration 0, Migiyokoryoku up these, (a), (b) is a 5 action point considering any _E 1, _{E R.} (C) corresponds to continuing traveling at the evaluation start time T _S without performing any arrival avoiding operation, and is represented as an action point E ₃ here. (D) are corresponding to steering to the limit to the right without completely decelerating, here referred to as the point E _2. It can be calculated more By defining the point as the arrival point A ₁ in the prediction time T _A of the vehicle corresponding to the respective working _{point, A R, A 3, A} 2 ( see FIG. 16.) . The avoidance target position calculation means 40 sets the avoidance target position G _A4 from the area defined by the quadrangle A ₁ A _R A ₃ A ₂ .

In the prediction time T _A, the vehicle 1200 if reaching forward from the predicted arrival position P ₁ of the obstacle 1400, will not likely to collide with the obstacle 1400 to a later time. Therefore, in the X-axis direction, it is desirable to set the avoidance target position ahead of the imaginary line s _x spaced by Δ _x from the occupied area of the radius r centered on the position P ₁ . Further, in the left area from the position P _1, the vehicle 1200 is undesirable as fear may avoid target position would reach the position of the obstacle 1400 in the process of reaching the avoidance target position. Therefore, it is desirable to set the avoidance target position on the right side of the imaginary line s _y that is spaced by Δ _y from the occupied area having the radius r centered on the position P ₁ in the Y-axis direction. Within the area of the quadrangle A ₁ A _R A ₃ A ₂ , the width of the vehicle from the area spaced by the two virtual lines s _x and s _y from the occupied area of radius r centered on the position P ₁ DOO sets the avoidance target located close to the most position a ₁ in consideration of length. In the case of FIG. 14, the coordinates of the avoidance target position _GA4 can be expressed by the following equation (42).

G _A4 {x _p (t _A ) + Δ _x + B / 2, y _p (t _A ) + Δ _y + L _R } (42)
Other processes are the same as those in the second and third embodiments.

Thus the results of calculating the avoidance target position G _A4, the movement locus of the vehicle 1200 in the case of performing reached avoidance control according avoidance operation quantity calculated at the current time t ₀ becomes one shown in FIG. 17, the deceleration By loosening and avoiding in the right direction, it is possible to realize a reaching avoidance motion with a margin without being affected by the uncertainty of the behavior of the obstacle 1400. In FIG. 17, the vehicle 1200 (G _A4 ) and the obstacle 1400 (P ₁ ) at the predicted time T _A are indicated by solid lines, and the vehicle 1200 (A ₀ ) and the obstacle 1400 (P ₀ ) at the evaluation start time T _S are shown. When shows the movement locus of the vehicle 1200 and an obstacle 1400 up to the predicted time T _a by the two-dot chain line.

In the first to third embodiments, as shown in FIG. 5, the initially set deceleration d ₀ is fixed, and the avoidance target position is set within the range of lateral force that can be additionally generated. the avoidance target position G _a has been set. This is because it is a basic operation for ensuring safety to decelerate and reduce the vehicle speed.

In contrast, in the method of calculating the avoidance operation amount shown in Example 4, the deceleration is corrected less than d ₀ is the initial setting value, using the range of lateral forces that can cause that has spread this modified In consideration of this, the avoidance target position _GA4 is set. Thereby, in the calculation method of Example 4, the range of the lateral force that can be generated by the restriction of the tire frictional force can be widened, and the room for avoidance in the lateral direction can be increased.

In Example 1 to Example 3, the scene assumed in FIG. 3, on the basis of the determination result calculated by the estimated arrival means 38, movement amount (steering amount) is set around the target position G _A on the left side is smaller It was. Such setting of the avoidance target position is not only a reasonable target setting when the accuracy of predicting the behavior of the obstacle is high, but also has an advantage that the movement amount (steering amount) can be reduced.

  On the other hand, in Example 4, since the avoidance operation amount toward the direction opposite to the direction in which the obstacle 1400 exists is calculated and executed immediately after the arrival avoidance control is started, the driver feels uncomfortable. Can be calculated and executed.

In the fourth embodiment, four operation amounts corresponding to the limit range of the application point of the tire friction force are set, and the avoidance target position G _A4 is set from the area of the quadrilateral A ₁ A _R A ₀ A _2. Although it was a structure, this score can be increased suitably. Increasing the number of points increases the amount of calculation, but the avoidance target position can be set from a region closer to the limit range of each tire 33 defined by the tire friction circle.

  Therefore, according to the avoidance operation calculation device according to the present invention, the behavior that is stable by the braking control and the steering control, that is, the force acting on the host vehicle is set within a range smaller than the maximum value of the grip force of the host vehicle tire. A driving operation amount that can avoid the vehicle from reaching the position of the obstacle can be calculated.

  Further, according to the avoidance control device according to the present invention, the host vehicle has a stable behavior by the braking control and the steering control, that is, the force acting on the host vehicle is set within a range smaller than the maximum value of the grip force of the tire of the host vehicle. The vehicle avoiding operation for avoiding the obstacle can be performed by the driving operation capable of avoiding reaching the position of the obstacle.

According to the invention of claim 1 Contact and claim 17, acceleration forces generated in the vehicle, so that the resultant force of the deceleration force and the lateral force, and the smaller range than the maximum value of the grip of the vehicle tire Since the avoidance operation amount is calculated, it is possible to calculate the avoidance operation amount that can avoid reaching the position of the obstacle without causing unexpected behavior in the host vehicle.
Further, according to the invention of claim 1 and claim 17, since the avoidance operation amount can be obtained as a time series based on the optimization of the evaluation function, compared with the case of determining a single target control amount, A smoother and more accurate avoidance operation amount can be calculated.

According to the invention of claim 2 and claim 18 , it is possible to calculate an effective avoidance operation amount not only for a stationary obstacle but also for a moving obstacle.

According to the invention of claim 3 and claim 19 , since the avoidance target position is calculated based on the limit lateral force corresponding to the arbitrary deceleration force, the steering amount to be added to the assumed arbitrary deceleration operation amount is calculated. Can do.

According to the invention of claim 4 and claim 20 , since the avoidance target position is calculated in a polygonal region based on a plurality of different limit lateral forces, obstacle avoidance is performed within the limit range of the grip force of the tire. It is possible to calculate an avoidance operation amount by a combination of a deceleration operation amount and a steering amount suitable for the above.

According to the fifth and twenty-first aspects of the present invention, the optimization problem is calculated by optimizing the amount of correction for the operation assumed when calculating the predicted arrival point, not the operation amount for avoiding itself. Can be formulated as an easy-to-solve problem, and the operation amount calculation can be speeded up.

According to the sixth and twenty-second aspects of the present invention, the collision possibility determination is performed when the deceleration is set to 0 prior to the calculation of the avoidance operation amount. It can prevent starting and giving a driver uncomfortable feeling.

According to the seventh and twenty- third aspects of the present invention, when the avoidance by steering is unnecessary, it is possible to command the avoidance operation amount for executing only the braking.

According to the eighth and twenty-fourth aspects of the present invention, it is possible to calculate a highly accurate avoidance operation amount by changing the maximum grip force and changing the limit range of the resultant force according to the road surface condition. For this reason, for example, even in slippery road conditions, the avoidance operation amount can be calculated within the range of tire friction force according to the road.

According to the ninth and twenty-fifth aspects of the present invention, the avoidance operation amount can be calculated in consideration of the arrival state of the vehicle, so that the arrival of the obstacle at the position of the obstacle can be surely avoided with a smaller avoidance operation. The avoidance operation amount that can be calculated can be calculated.

According to the tenth and twenty-sixth aspects, since the braking operation can be executed by the braking motion control means, the calculated avoidance operation amount can be realized with certainty.

According to the eleventh and twenty-seventh aspects of the present invention, since the arrival prediction is performed on the assumption of the deceleration when the braking motion control means generates the maximum braking force on the host vehicle, the avoidance target position is determined. Since it is only necessary to assume a case where the deceleration is loosened when setting, the amount of calculation associated with the calculation of the avoidance target position can be reduced.

According to the twelfth and twenty-eighth aspects of the present invention, it is possible to calculate the avoidance operation amount suitable for the braking motion control means provided in the vehicle.

According to the invention of claim 13 and claim 29 , not only the deceleration operation but also the steering can be executed by the steering control means in the calculated avoidance operation amount, so that the calculated avoidance operation amount is more reliably realized. Can be made.

According to the invention of claim 18 and claim 30 , by determining reachability even during execution of the avoidance control, if the obstacle behaves differently from the initial prediction, collision avoidance The operation is recalculated, and the avoidance operation corresponding to the change in the behavior of the obstacle can be executed.

  In each of the above-described embodiments, the vehicle motion control unit performs the steering of the vehicle based on the optimal driving operation amount calculated by the avoidance operation calculation device. The driving operation by the driver may be performed in an auxiliary manner. In this case, for example, the vehicle motion control means may be steered according to the difference between the optimum driving operation amount and the driving operation performed by the driver, and when the driver performs the driving operation, Another steering may be stopped.

  Further, in each of the above-described embodiments, the avoidance control device including the avoidance operation calculating device is adopted for the vehicle, and the vehicle is controlled by the vehicle motion control means based on the calculated optimum driving operation amount. However, the vehicle may not be steered. In this case, for example, only the avoidance operation calculation device is adopted in the vehicle, a display is installed in the passenger compartment, and a movement locus for avoiding arrival that matches the optimum driving operation amount is displayed on the display, so that the position of the obstacle is displayed. Steering for avoiding reaching can be assisted.

In the avoidance operation calculation device and the avoidance control device shown in each of the above-described embodiments, the avoidance operation amount is calculated by a different method. However, the methods can be appropriately combined. For example, setting the avoidance target position, in Examples 1 and 2, the operation amount is set to the left position A ₁ to be small, the resultant force of the deceleration force and the lateral force, a tire friction circle within the limits may be set to the left position a _1, is not limited to those described above.

  Further, in each of the above-described embodiments, the avoidance operation calculation device steers the vehicle based on the front wheel steering δ that is the calculated optimum driving operation amount, but depending on the calculated optimum driving operation amount, Steering may be performed by a braking mechanism, and is not limited to the above-described embodiment.

It is a top view which shows typically the vehicle by which the avoidance operation calculation apparatus and avoidance control apparatus which concern on this invention were employ | adopted. It is a block diagram which shows an avoidance control apparatus. It is a typical top view which shows the scene of Example 1 in which it was assumed that the arrival avoidance was actually performed, and the state by which the processed information was expand | deployed by the coordinate system is also shown. In the scene of FIG. 3, it is a top view for demonstrating the process by an arrival prediction means. It is a graph which shows a tire friction circle. It is a typical top view which shows the moving range of the vehicle according to the limit range of a tire friction circle. It is a top view which shows the state of the arrival avoidance by the avoidance operation amount of Example 1. FIG. It is a flowchart which shows the process of an avoidance operation calculation apparatus. It is a graph which shows an example of the functional shape of the tire lateral force in a vehicle motion model. It is a graph which shows an example of the avoidance operation amount calculated. It is a typical top view which shows the scene of Example 3 assumed so that an actual arrival avoidance might be performed. 14 is a flowchart illustrating processing of the avoidance operation calculation device according to the third embodiment. FIG. 10 is a schematic plan view showing a moving range of a vehicle according to a limit range of a tire friction circle of Example 3. FIG. 10 is a plan view illustrating a movement locus for avoiding an obstacle of a vehicle performed according to an avoidance operation amount according to a third embodiment. It is a graph which shows a tire friction circle, and the action point for demonstrating the calculation method of the avoidance target position by Example 4 is shown. FIG. 10 is a plan view for explaining a calculation method of an avoidance target position according to a fourth embodiment. FIG. 10 is a plan view illustrating a movement locus for avoiding an obstacle of a vehicle performed according to an avoidance operation amount according to a fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Avoidance operation calculation apparatus 11 Avoidance control apparatus 12,120,1200 Vehicle 13 Road 14,140,1400 Obstacle 15 Vehicle motion control means 16 (It comprises a part of obstacle detection means and the own vehicle information detection means) Camera 17 Vehicle speed sensor 18 (which constitutes part of the vehicle information detection means) Yaw rate sensor 19 (which constitutes part of the vehicle information detection means) Acceleration sensor 28 (which constitutes part of the vehicle information detection means) Vehicle information processing unit 29 (which forms part of vehicle information detection means) Obstacle information processing unit 30 (which forms part of obstacle detection means) Avoidance operation amount generation means 35 Reachability determination means 36 Own vehicle movement locus calculation means 37 the obstacle movement locus prediction unit 38 reaches prediction means 39 friction force limit setting means 40 around the target position calculating means 41 avoidance operation quantity calculating means d _{0 (optional)} deceleration T Evaluation start time _{T A} predicted time _{G A, G A3, G A4} avoidance target position [delta] ^* (as avoidance operation amount) steering amount ^{p *} (as avoidance operation quantity a is deceleration operation amount) of the brake pressure value

Claims (30)

Obstacle detection means for detecting an obstacle present on the road ahead of the own vehicle, own vehicle information detection means for detecting the traveling state of the own vehicle, the own vehicle information detection means, and the obstacle detection means An avoidance operation amount generating device including an avoidance operation amount generating means for generating an avoidance operation amount for the host vehicle to avoid the obstacle based on detection information from the vehicle,
The avoidance operation quantity generating means, the acceleration forces occurring vehicle deceleration force and resultant force of the lateral force calculates the avoidance maneuver amount in smaller than the maximum value range of tire grip force of the vehicle ,
The avoidance operation amount generation means sets a maximum grip force that can be exhibited by the tire of the host vehicle on a road on which the host vehicle travels, and sets a limit range of the combined force based on the maximum grip force Limit setting means;
Self-vehicle movement trajectory calculation means for setting an arbitrary deceleration that can occur in the host vehicle due to a deceleration force within the limit range, and calculating a predicted deceleration movement trajectory when the host vehicle is decelerated by the arbitrary deceleration When,
It is determined whether or not the host vehicle on the predicted deceleration movement trajectory reaches the position of the obstacle, and it is predicted that the host vehicle reaches the position of the obstacle when it is determined that the host vehicle will arrive. An arrival prediction means for calculating an estimated time;
An operation region that the host vehicle can reach at the predicted time by the combined force within the limit range is set, and an avoidance target position at which the host vehicle can avoid the obstacle is calculated in the operation region. Avoidance target position calculating means;
An avoidance operation amount calculation means for calculating a deceleration operation amount and a steering amount for causing the host vehicle to reach the avoidance target position;
The deceleration operation amount and the steering amount become the avoidance operation amount,
The avoidance operation amount calculation means sets an evaluation start time that is a time when the obstacle is detected, divides the time from the evaluation start time to the predicted time at a predetermined interval, and operates the vehicle to the host vehicle. Based on a vehicle motion model describing a predicted travel locus of the host vehicle with respect to the vehicle, the vehicle operation amount to the host vehicle between the evaluation start time and the predicted time is evaluated numerically, and at least at the predicted time The optimal driving operation amount at which the evaluation function for numerically evaluating the approach state of the predicted arrival position of the host vehicle based on the predicted traveling locus from the target avoidance position and the vehicle motion model is the best value is set for each predetermined time. calculated, avoidance maneuver calculation device, wherein the optimum driving maneuver amount is characterized Rukoto such as the avoidance operation amount. The avoidance operation amount generation means includes obstacle movement trajectory prediction means for calculating a predicted obstacle movement trajectory that is a predicted movement trajectory of the obstacle based on information on the obstacle detected by the obstacle detection means. The arrival prediction means determines whether or not the host vehicle on the predicted deceleration movement trajectory reaches the position of the obstacle on the predicted obstacle movement trajectory, and arrives when it is determined to reach it avoidance maneuver calculation device according to claim 1, characterized that you calculate a predicted time to be expected. The avoidance target position calculation means calculates an arbitrary deceleration force that causes the host vehicle to make the arbitrary deceleration, and applies to the host vehicle corresponding to the arbitrary deceleration force so that the combined force is within the limit range. The avoidance operation calculation device according to claim 1 or 2 , wherein a limit lateral force is calculated, and the avoidance target position is calculated within a range that can be reached with a lateral force smaller than the limit lateral force . The avoidance target position calculation means calculates an arbitrary deceleration force that causes the host vehicle to make the arbitrary deceleration, and applies to the host vehicle corresponding to the arbitrary deceleration force so that the combined force is within the limit range. Calculate the limit lateral force,
Further, at least one virtual deceleration force that is smaller than the arbitrary deceleration force within the limit range is set, and the vehicle to the host vehicle corresponding to each virtual deceleration force is set so that the combined force is within the limit range. Calculate the limit lateral force,
In the predicted time,
A predicted position of the host vehicle when the arbitrary deceleration force is applied to the host vehicle;
A predicted position of the host vehicle when the arbitrary deceleration force and a limit lateral force corresponding to the arbitrary deceleration force are applied to the host vehicle;
Each predicted position of the host vehicle when the virtual deceleration force is applied to the host vehicle;
The predicted positions of the host vehicle when the virtual deceleration force and the limit lateral force corresponding to the virtual deceleration force are applied to the host vehicle;
Avoidance maneuver calculation device according to claim 1 or claim 2, characterized in that to calculate the avoidance target position configured polygonal area by. The avoidance operation amount calculation means sets the deceleration operation amount corresponding to the arbitrary deceleration used for calculating the predicted movement locus of the own vehicle in the own vehicle movement locus calculation means as an initial value of the deceleration operation amount. The avoidance operation calculation device according to any one of claims 1 to 4, wherein the avoidance operation calculation device is provided. Further, a travel trajectory when the host vehicle maintains the travel state of the host vehicle when the obstacle detection unit detects the obstacle is calculated as a stationary predicted trajectory, and the host vehicle on the predicted stationary trajectory Is provided with reachability determination means for determining whether or not the vehicle reaches the position of the obstacle, and the avoidance operation is performed when it is determined by the reachability determination means that the host vehicle reaches the position of the obstacle avoidance maneuver calculation device according to any one of claims 1 to 5 in which the amount generating means is characterized that you initiate calculation of the avoidance operation amount. When the arrival prediction unit of the avoidance operation amount generation unit determines that the host vehicle on the predicted deceleration trajectory does not reach the position of the obstacle, the avoidance operation amount calculation unit of the avoidance operation amount generation unit is , claim from claim 1, wherein calculating a deceleration operation amount for realizing the arbitrary deceleration set by the vehicle moving trajectory calculation means, the deceleration operation amount and said Rukoto such as the avoidance operation quantity The avoidance operation calculation device according to any one of 6. Furthermore, road surface information acquisition means for acquiring information on the road surface friction coefficient of the road on which the host vehicle travels is provided, and the frictional force limit setting means of the avoidance operation amount generation means is configured to detect the vehicle according to the road surface friction coefficient. avoidance maneuver calculation device according to any one of claims 1 to 7, characterized in that to change the change the maximum grip force limit range of the resultant force of the tires of the vehicle. When the arrival prediction means determines that the own vehicle on the predicted deceleration movement trajectory reaches the position of the obstacle, the own vehicle and the obstacle when the own vehicle reaches the position of the obstacle avoidance maneuver calculation device according to any one of claims 8 positional relationship claim 1, characterized that you calculated as the state reached with. An avoidance operation calculating device according to any one of claims 1 to 9, and a braking motion control means for performing a braking operation of the host vehicle based on the avoidance operation amount calculated by the avoidance operation calculating device. avoidance control device according to claim Rukoto and a vehicle motion control means comprising. The own vehicle movement trajectory calculating means of the avoidance operation calculating device is configured to determine a deceleration acting on the own vehicle when the braking motion control means generates a maximum braking force on the own vehicle. avoidance control device according to 請 Motomeko 1 0 you and sets as. It said friction force limit setting means in claim 10 or claim 11, characterized in that you set the maximum braking force that the control motion control means can exhibit a maximum value of the tire grip force of the vehicle The avoidance control device described . The vehicle motion control device, avoidance control device according to any one of the avoidance maneuver based on said amount claims 12 to claim 10, characterized in Rukoto comprises a steering control means for steering the vehicle . The avoidance operation amount calculation means of the avoidance operation calculation device sets an evaluation start time that is a time when the obstacle is detected, divides the time from the evaluation start time to the prediction time at a predetermined interval, Whether or not the host vehicle reaches the position of the obstacle on the predicted avoidance movement trajectory based on the avoidance operation amount is determined every predetermined time. The means discards the calculated avoidance operation amount and newly calculates an avoidance operation amount, and the vehicle motion control means performs the driving operation of the host vehicle with the newly calculated avoidance operation amount. The avoidance control device according to any one of claims 10 to 13. A vehicle comprising the avoidance operation calculation device according to any one of claims 1 to 9. A vehicle comprising the avoidance control device according to any one of claims 10 and 14. An obstacle present on a road ahead of the host vehicle is detected, a traveling state of the host vehicle is detected, and the host vehicle avoids the obstacle based on the traveling state and the detection information of the obstacle. An avoidance operation calculation method for generating an avoidance operation amount for
Calculating the avoidance operation amount within a range where the combined force of acceleration force, deceleration force and lateral force generated in the host vehicle is smaller than the maximum value of the grip force of the tire of the host vehicle;
Setting a maximum grip force that the tire of the host vehicle can exhibit on the road on which the host vehicle travels, and setting a limit range of the combined force based on the maximum grip force;
Set an arbitrary deceleration that can occur in the host vehicle due to a deceleration force within the limit range, and calculate a predicted deceleration movement locus when the host vehicle is decelerated by the arbitrary deceleration,
It is determined whether or not the host vehicle on the predicted deceleration movement trajectory reaches the position of the obstacle, and it is predicted that the host vehicle reaches the position of the obstacle when it is determined that the host vehicle will arrive. Calculate the predicted time,
An operation region that the host vehicle can reach at the predicted time by a combined force within the limit range is set, and an avoidance target position at which the host vehicle can avoid the obstacle is calculated in the operation region. ,
Calculating a deceleration operation amount and a steering amount for causing the host vehicle to reach the avoidance target position;
The deceleration operation amount and the steering amount are set as the avoidance operation amount,
An evaluation start time that is the time at which the obstacle is detected is set, a time from the evaluation start time to the prediction time is divided at a predetermined interval, and the predicted travel locus of the host vehicle with respect to the vehicle operation on the host vehicle Based on a vehicle movement model that describes the vehicle operation amount to the host vehicle between the evaluation start time and the prediction time numerically, and at least the target avoidance position and the vehicle movement at the prediction time An optimum driving operation amount at which an evaluation function that numerically evaluates an approach state of the predicted arrival position of the host vehicle based on the predicted traveling locus from a model becomes a best value is calculated at each predetermined time, and each optimum driving is calculated. An avoidance operation calculation method characterized in that an operation amount is the avoidance operation amount . A predicted obstacle movement trajectory that is a predicted movement trajectory of the obstacle is calculated based on the obstacle information, and the own vehicle on the predicted deceleration movement trajectory is positioned at the position of the obstacle on the predicted obstacle movement trajectory. 18. The avoidance operation calculation method according to claim 17, wherein it is determined whether or not it is reached, and a predicted time that is predicted to be reached when it is determined to be reached is calculated. An arbitrary deceleration force that causes the host vehicle to be the arbitrary deceleration is calculated, a limit lateral force to the host vehicle corresponding to the arbitrary deceleration force is calculated so that the combined force is within the limit range, The avoidance operation calculation method according to claim 17 or 18, wherein the avoidance target position is calculated within a range that can be reached with a lateral force smaller than a limit lateral force . Calculating an arbitrary deceleration force that causes the host vehicle to be the arbitrary deceleration, and calculating a limit lateral force to the host vehicle corresponding to the arbitrary deceleration force so that the combined force is within the limit range;
Further, at least one virtual deceleration force that is smaller than the arbitrary deceleration force within the limit range is set, and the vehicle to the host vehicle corresponding to each virtual deceleration force is set so that the combined force is within the limit range. Calculate the limit lateral force,
In the predicted time,
A predicted position of the host vehicle when the arbitrary deceleration force is applied to the host vehicle;
A predicted position of the host vehicle when the arbitrary deceleration force and a limit lateral force corresponding to the arbitrary deceleration force are applied to the host vehicle;
Each predicted position of the host vehicle when the virtual deceleration force is applied to the host vehicle;
The predicted positions of the host vehicle when the virtual deceleration force and the limit lateral force corresponding to the virtual deceleration force are applied to the host vehicle;
The avoidance operation calculation method according to claim 17 or 18 , wherein the avoidance target position is calculated within a polygonal area constituted by : Claim 17, characterized in that the initial value of the expected movement locus respond to the arbitrary deceleration used to calculate the deceleration operation amount deceleration operation amount of the vehicle in the vehicle moving trajectory calculation means avoidance maneuver calculating method according to any one of claims 20 to. Further, a stationary prediction trajectory is calculated using a traveling trajectory when the host vehicle maintains the traveling state of the host vehicle when the obstacle is detected as a stationary predicted trajectory, and the own vehicle on the stationary predicted trajectory is It determines whether to reach the position of the obstacle, if the vehicle on the stationary anticipated course is determined to reach the position of the obstacle, wherein, characterized in that to start the calculation of the avoidance operation quantity The avoidance operation calculation method according to any one of claims 17 to 21. When it is determined that the host vehicle on the predicted deceleration trajectory does not reach the position of the obstacle, a deceleration operation amount that realizes the arbitrary deceleration set by the host vehicle travel trajectory calculating unit is calculated, The avoidance operation calculation method according to any one of claims 17 to 22, wherein the deceleration operation amount is set as the avoidance operation amount . Further, information on a road surface friction coefficient of the road on which the host vehicle travels is acquired, and the maximum grip force of the tire of the host vehicle is changed according to the road surface friction coefficient to change a limit range of the combined force. The avoidance operation calculation method according to any one of claims 17 to 23, wherein: When it is determined that the host vehicle on the predicted deceleration movement locus reaches the position of the obstacle, the positional relationship between the host vehicle and the obstacle when the host vehicle reaches the position of the obstacle is reached. The avoidance operation calculation method according to any one of claims 17 to 24 , wherein the calculation is performed as a state . 26. Braking of the host vehicle by a braking motion control device of a vehicle motion control means included in the host vehicle based on the avoidance operation amount calculated by the avoidance operation calculating method according to any one of claims 17 to 25. An avoidance control method characterized by performing an operation . The 請 Motomeko 2 6 and sets a deceleration that acts on the free-vehicle when the brake motor control means has caused the maximum braking force to said vehicle as said arbitrary deceleration The avoidance control method described . Avoidance control method according to claim 26 or claim 2 7, characterized in that to set the maximum braking force that the control motion control means can exhibit a maximum value of the tire grip force of the vehicle. The avoidance control method according to any one of claims 26 to 28, wherein the host vehicle is steered by a steering control means of the vehicle motion control means based on the avoidance operation amount . An evaluation start time that is the time at which the obstacle is detected is set, a time from the evaluation start time to the prediction time is divided at a predetermined interval, and prediction avoidance based on the avoidance operation amount is performed at each predetermined time It is determined whether or not the host vehicle on the movement trajectory reaches the position of the obstacle, and if it is determined to reach, the calculated avoidance operation amount is discarded and a new avoidance operation amount is calculated. 30. The avoidance control method according to claim 26 , wherein the driving operation of the host vehicle is performed with the newly calculated avoidance operation amount .

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