Braking / driving force control method and braking / driving force control device

Abstract

To reduce a sense of discomfort when an own vehicle is decelerated on the basis of a speed profile according to a relative distance between a target position in front and the own vehicle.SOLUTION: A braking-driving force control method includes: calculating a relative distance between a target position in front and an own vehicle (S3); calculating a first target speed on the basis of a first speed profile which is a speed profile showing a vehicle speed according to a distance to the target position, and in which a prescribed set speed is reached before the target position by decelerating at first deceleration (S4); calculating a second target speed on the basis of a second speed profile which is set as a speed profile according to a distance to the target position, and in which the set speed is reached at the target position by decelerating at second deceleration greater than the first deceleration (S5); and correcting braking-driving force according to accelerator operation by subtracting the greater amount of correction with the increase of a ratio obtained by dividing a difference obtained by subtracting the first target speed from a relative speed of the own vehicle with respect to the target position, by a difference obtained by subtracting the first target speed from the second target speed (S7, S8).SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a braking / driving force control method and a braking / driving force control device. [Background technology]

[0002] Patent document 1 proposes a technology that predicts the point where the vehicle will stop, generates a planned speed, which is a target value for the vehicle speed according to the distance to the predicted point, and controls the deceleration of the vehicle so that it follows the generated planned speed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-208829 Summary of the Invention [Problem to be solved by the invention]

[0004] However, there are individual differences among drivers in the speed adjustment for decelerating the vehicle in accordance with the relative distance between the vehicle and a target position ahead of the vehicle, and therefore, if the vehicle is decelerated using a speed profile that differs from the vehicle speed change expected by the driver, the driver may feel uncomfortable. The present invention aims to reduce the sense of discomfort felt by the driver when the host vehicle is decelerated based on a speed profile according to the relative distance between the host vehicle and a target position ahead of the host vehicle. [Means for solving the problem]

[0005] A braking / driving force control method according to one aspect of the present invention calculates braking / driving forces according to an operation amount of an accelerator pedal of the host vehicle, calculates a relative distance between a current position of the host vehicle and a target position that is a predetermined position ahead in the traveling direction of the host vehicle, calculates a first target speed based on a speed profile that indicates a vehicle speed according to the distance to the target position, the first speed profile being a first speed profile that decelerates the host vehicle at a first deceleration to reach a predetermined set speed at a first point that is a first distance closer to the host vehicle than the target position, and maintains the set speed from the first point to the target position, and the relative distance, and sets a first target speed as the speed profile according to the distance to the target position. a second target speed is calculated based on the relative distance and a second speed profile in which the vehicle is decelerated at a second deceleration that is greater than the first deceleration to reach the set speed at the target position; a relative speed of the vehicle with respect to the target position is detected; if the relative speed is equal to or greater than the first target speed, a larger correction amount is calculated the greater the ratio of the difference obtained by subtracting the first target speed from the relative speed divided by the difference obtained by subtracting the first target speed from the second target speed; corrected braking / driving forces are calculated by subtracting the correction amount from braking / driving forces calculated in accordance with the amount of operation of the accelerator pedal; and the braking / driving forces of the vehicle are controlled based on the calculated corrected braking / driving forces. [Effects of the Invention]

[0006] According to the present invention, it is possible to reduce the sense of discomfort felt by the driver when the host vehicle is decelerated based on a speed profile according to the relative distance between the host vehicle and a target position ahead of the host vehicle. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing an example of a schematic configuration of a braking / driving force control device according to an embodiment; [Figure 2] FIG. 4 is a schematic diagram of braking / driving torque according to accelerator pedal depression amount. [Figure 3] FIG. 3 is an explanatory diagram of an example of a braking / driving force control method according to the first embodiment. [Figure 4] FIG. 10 is a diagram showing a comparative example of a first speed profile that reaches a predetermined set speed at a target position. [Figure 5]FIG. 10(a) is an explanatory diagram of an example of a setting example of a first speed profile, and FIG. 10(b) is an explanatory diagram of another example of a setting example of a first speed profile. [Figure 6] 2 is a block diagram illustrating an example of a functional configuration of a controller in FIG. 1. FIG. [Figure 7] FIG. 3 is a block diagram showing an example of a functional configuration of a correction torque setting unit according to the first embodiment. [Figure 8] 3 is a flowchart illustrating an example of a braking / driving force control method according to the first embodiment. [Figure 9] FIG. 10 is a block diagram showing an example of a functional configuration of a correction torque setting unit according to a second embodiment. [Figure 10] FIG. 10 is an explanatory diagram of an example of a braking / driving force control method according to a second embodiment. [Figure 11] FIG. 11 is a block diagram showing an example of a functional configuration of a correction torque setting unit according to a third embodiment. [Figure 12] FIG. 10 is a diagram illustrating an example of the characteristics of a relative speed sensitive gain. [Figure 13] FIG. 10 is a block diagram showing an example of a functional configuration of a correction torque setting unit according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, identical or similar parts are designated by identical or similar reference numerals, and redundant explanations will be omitted. Each drawing is a schematic view, and may differ from the actual product. The embodiments shown below exemplify devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention is not limited to the devices and methods exemplified in the following embodiments. The technical concept of the present invention can be modified in various ways within the technical scope described in the claims.

[0009] (First embodiment) (composition) Referring to Figure 1, the host vehicle 1 is equipped with a braking / driving force control device 10. The braking / driving force control device 10 controls the driving torque and braking torque (hereinafter, collectively referred to as "braking / driving torque") generated in the host vehicle 1 in accordance with the amount of operation by the driver of an accelerator pedal, which is a driving force instruction operator. Braking / driving torques corresponding to accelerator pedal operation amount Ac will be explained schematically with reference to Figure 2. Braking / driving force control device 10 generates driving torque on the vehicle when accelerator pedal operation amount Ac is greater than a predetermined threshold Ac0, and generates braking torque on the vehicle when operation amount Ac is smaller than the predetermined threshold Ac0. This type of control of braking / driving torques corresponding to accelerator pedal operation amount Ac may be referred to as "one-pedal control" in the following explanation.

[0010] When the operation amount Ac is at its maximum value (100%), the drive torque is at its maximum value (100%), and as the operation amount Ac decreases, the drive torque decreases, and when the operation amount Ac reaches a threshold value Ac0, the drive torque becomes 0. The threshold value Ac0 may be, for example, about one-fourth (25%) of the maximum value of the operation amount Ac. When the operation amount Ac becomes smaller than the threshold value Ac0, the braking torque increases as the operation amount Ac decreases, and when the operation amount Ac reaches 0, the braking torque becomes a predetermined value Td0. Referring to Fig. 1, the braking / driving force control device 10 includes a positioning device 11, a map database (map DB) 12, an external sensor 13, a vehicle sensor 14, a controller 15, and a braking / driving force generation mechanism 16.

[0011] The positioning device 11 measures the current position of the vehicle 1. The positioning device 11 may include, for example, a Global Navigation System (GNSS) receiver. The GNSS receiver is, for example, a Global Positioning System (GPS) receiver, and receives radio waves from multiple navigation satellites to measure the current position of the vehicle 1. The positioning device 11 may also be an inertial navigation system. The map DB 12 is a database of map information. The map DB 12 may be, for example, a map DB provided in a car navigation system. The map DB 12 may be, for example, high-precision map data suitable as map information for autonomous driving. The controller 15 acquires information about the surrounding conditions of the current position of the host vehicle from the map DB 12. For example, the controller 15 acquires information about stop lines present ahead in the traveling direction of the host vehicle 1 from the map DB 12.

[0012] The external sensor 13 detects various information (ambient environment information) about the environment surrounding the vehicle 1. The external sensor 13 detects the environment surrounding the vehicle 1, such as objects present around the vehicle 1, the relative positions between the vehicle 1 and the objects, the distance between the vehicle 1 and the objects, and the direction in which the objects are present. The external sensor 13 outputs the detected information about the ambient environment to the controller 15 as ambient environment information. For example, the external sensor 13 detects the relative positions of moving objects and stationary targets, such as other vehicles around the host vehicle 1, relative to the host vehicle 1. Here, stationary targets include, for example, traffic lights provided on the road on which the host vehicle 1 is traveling, lines on the road surface (lane markings, etc.), curbs on the shoulders of the road, guardrails, stop lines and stationary objects (for example, obstacles) on the road on which the host vehicle 1 is traveling.

[0013] The external sensor 13 may include a monocular camera such as a full HD color camera. The camera captures an image including a recognition target in the environment surrounding the vehicle 1, and outputs the captured image to the controller 15 as ambient environment information. The external sensor 13 may also include a distance measuring device such as a laser range finder (LRF), radar, or a laser radar such as LiDAR (Light Detection and Ranging). The distance measuring device detects the relative position of the vehicle, which is determined by the relative distance and direction to an object present around the vehicle. The distance measuring device outputs the detected distance data to the controller 15 as surrounding environment information.

[0014] The vehicle sensor 14 detects various information (vehicle information) obtained from the host vehicle 1. The vehicle sensor 14 includes, for example, a vehicle speed sensor that detects the traveling speed (vehicle speed) V of the host vehicle 1, a wheel speed sensor that detects the rotational speed of each tire equipped on the host vehicle 1, a three-axis acceleration sensor (G sensor) that detects the acceleration (including deceleration) in three axial directions of the host vehicle 1, a steering angle sensor that detects the steering angle of the steering wheel, a turning angle sensor that detects the turning angle of the steered wheels, a gyro sensor that detects the angular velocity generated in the host vehicle 1, a yaw rate sensor that detects the yaw rate, an accelerator sensor that detects the operation amount Ac of the accelerator pedal of the host vehicle 1, and a brake sensor that detects the brake operation amount by the driver.

[0015] The controller 15 is an electronic control unit that controls the braking and driving force of the host vehicle 1. The controller 15 includes a processor 20 and peripheral components such as a memory device 21. The processor 20 may be, for example, a CPU or an MPU. The memory device 21 may include a semiconductor memory device, a magnetic memory device, an optical memory device, etc. The memory device 21 may include memories such as a register, a cache memory, and a ROM and RAM used as a main memory device. The functions of the controller 15 described below are realized, for example, by the processor 20 executing a computer program stored in the memory device 21. The controller 15 may be formed of dedicated hardware for executing each of the information processes described below. For example, the controller 15 may include a functional logic circuit configured in a general-purpose semiconductor integrated circuit. For example, the controller 15 may include a PLD such as an FPGA.

[0016] The controller 15 sets a torque command value Tf for the driving torque or braking torque to be generated on the wheels of the host vehicle 1 in accordance with the accelerator pedal operation amount Ac, and drives the braking / driving force generation mechanism 16 in accordance with the torque command value Tf to generate the driving torque or braking torque in the host vehicle 1. The process of setting the torque command value Tf by the controller 15 will be described later. The driving / braking force generating mechanism 16 is a drive source connected to the wheels of the host vehicle 1, and is, for example, a drive motor, an internal combustion engine, or a brake actuator that generates driving torque or braking torque on the wheels of the host vehicle 1. In the following, in this embodiment, as an example, the driving / braking force generating mechanism 16 is assumed to be a drive motor. The driving / braking force generating mechanism 16 generates driving torque to drive the host vehicle 1 or braking torque to brake the host vehicle 1 in response to a control signal (torque command value Tf) from the controller 15.

[0017] Next, a description will be given of the process of setting the torque command value by the controller 15. The controller 15 executes so-called one-pedal control, which performs control such that acceleration occurs when the accelerator pedal is depressed and deceleration occurs when the accelerator pedal is released. 3. When the controller 15 detects a stationary target or a moving object in front of the host vehicle 1 in the traveling direction using the external sensor 13 or the map DB 12, the controller 15 sets a target position Xtrg in front of the traveling direction of the host vehicle 1, where the relative speed Vr of the host vehicle 1 with respect to the stationary target or the moving object is set to a predetermined set speed Vs. For example, when a stationary target is detected, a point a predetermined distance before the stationary target is set as the target position Xtrg where the host vehicle 1 is to stop (i.e., the set speed Vs is 0). Also, for example, when a moving object is detected in front of the host vehicle, the controller 15 sets the speed Vf of the moving object to the predetermined set speed Vs, and sets a point a predetermined distance before the moving object as the target position Xtrg. In other words, the target position Xtrg is set to a predetermined position in front of the traveling direction of the host vehicle, such as a position where the host vehicle 1 is to stop or a point a predetermined distance before the moving object in front. FIG. 3 shows an example in which a leading vehicle 2 traveling in front of the host vehicle 1 in the traveling direction is detected as a moving object.

[0018] The controller 15 calculates the relative distance Xr between the current position of the host vehicle 1 and the target position Xtrg, and controls the vehicle speed V of the host vehicle 1 using speed profiles P1, P2 according to the distance to the target position Xtrg. At this time, as described above, there are individual differences among drivers in the speed adjustment for decelerating the vehicle 1 in accordance with the relative distance Xr between the target position Xtrg ahead of the vehicle 1 and the vehicle 1. For this reason, if the vehicle 1 is decelerated using a speed profile that differs from the vehicle speed change expected by the driver, the driver may feel uncomfortable.

[0019] Therefore, controller 15 detects the current relative speed Vr of vehicle 1 with respect to target position Xtrg, calculates correction torque Tc according to the difference between relative speed Vr and the speed profile, calculates torque command value Tf by subtracting correction torque Tc from basic braking / driving torque Tb calculated according to accelerator pedal operation amount Ac, and drives braking / driving force generation mechanism 16 based on torque command value Tf to control the braking / driving torque of vehicle 1. In this way, even if the relative speed Vr exceeds the speed profile, the vehicle speed V of the host vehicle 1 is not directly controlled so that the relative speed Vr immediately changes in line with the speed profile, but the basic braking / driving torque Tb corresponding to the accelerator pedal operation amount Ac is reduced and corrected by the correction torque Tc. Therefore, the accelerator pedal operation amount Ac, which is the driver's intention, can be reflected in the speed adjustment of the host vehicle 1. As a result, it is possible to reduce the sense of discomfort felt by the driver when decelerating the host vehicle 1 based on the first speed profile P1.

[0020] For example, the controller 15 of the first embodiment sets a first speed profile P1 and a second speed profile P2 as speed profiles that indicate the vehicle speed according to the distance to the target position Xtrg. In Fig. 2, the thin solid line and the dashed dotted line show examples of the first speed profile P1 and the second speed profile P2, and the thick solid line shows an example of the change in the relative speed Vr. The first speed profile P1 decelerates at a first deceleration G1, reaches a predetermined set speed Vs at a first point Xo1 that is closer to the host vehicle 1 by a first distance D1 than the target position Xtrg, and maintains the set speed Vs from the first point Xo1 to the target position. The second speed profile P2 decelerates at a second deceleration G2 that is greater than the first deceleration G1, and reaches the set speed Vs at the target position Xtrg. The first deceleration G1 in the first embodiment may be set to a value equal to or less than the deceleration (e.g., 0.1 G) during relatively weak braking in everyday driving. The second deceleration G2 in the first embodiment may be set to a value equal to or less than the deceleration (e.g., 0.2 G) during relatively strong braking in everyday driving.

[0021] The controller 15 calculates a first target speed V1 of the host vehicle 1 based on the first speed profile P1 and the relative distance Xr, and calculates a second target speed V2 of the host vehicle 1 based on the second speed profile P2 and the relative distance Xr. For example, the first speed profile P1 may be set as a calculation formula for the first target speed V1 using the relative distance Xr as a variable. For example, the controller 15 may calculate the first target speed V1 based on the following formula (1).

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[0022] The first speed profile P1 in the above formula (1) is a speed profile (2×G1×Xr) that decelerates at a first deceleration G1 and reaches a set speed Vs at a target position Xtrg. 1 / 2 The speed of +Vs is the first offset speed Vo1 = (2 × G1 × Xo1) 1 / 2 The lower limit is obtained by lowering the speed by a set speed Vs. That is, the first speed profile P1 is a speed profile (2×G1×Xr) 1 / 2 This is a profile in which +Vs is offset downward in the profile characteristic diagram of FIG. 3 by a first offset speed Vo1, and the lower limit value is limited by the set speed Vs.

[0023] Further, for example, the second speed profile P2 may also be set as a calculation formula for the second target speed V2 using the relative distance Xr as a variable. For example, the controller 15 may calculate the second target speed V2 based on the following formula (2). V2=(2×G2×Xr) 1 / 2 +Vs…(2) The controller 15 detects the current relative speed Vr of the vehicle 1 with respect to the target position Xtrg. When the relative speed Vr is equal to or greater than the first target speed V1, the controller 15 calculates a larger correction torque Tc as the ratio (Vr-V1) / (V2-V1) obtained by dividing the difference obtained by subtracting the first target speed V1 from the relative speed Vr by the difference obtained by subtracting the first target speed V1 from the second target speed V2 increases. When the relative speed Vr is less than the first target speed V1, the controller 15 sets the correction torque Tc to 0.

[0024] Next, the reason why the first speed profile P1 is set so as to reach the predetermined set speed Vs at the first point Xo1 that is closer to the host vehicle 1 than the target position Xtrg by the first distance D1 will be explained. For comparison, FIG. 4 shows a first speed profile P1 that is set to reach a predetermined set speed Vs at a target position Xtrg. When a point a predetermined distance before a moving object ahead of the host vehicle 1 (leading vehicle 2 in the example of FIG. 3) is set as the target position Xtrg, the speed Vf of the moving object may fluctuate. As a result, for example, when the moving object decelerates and the relative distance between the host vehicle 1 and the moving object changes from Xr2 to Xr1, and the relative speed Vr changes from Vr1 to Vr2, the relative speed Vr exceeds the speed profiles P1 and P2, and the correction torque Tc changes from 0 to a positive value.

[0025] The correction torque Tc is set to a larger value as the ratio (Vr-V1) / (V2-V1) increases. Therefore, if the first speed profile P1 shown in FIG. 4 is set, when the host vehicle 1 approaches very close to the target position Xtrg, the denominator (V2-V1) approaches 0, and the change in correction torque Tc becomes large. As a result, the braking / driving torque of the host vehicle 1 corrected by the correction torque Tc fluctuates greatly, which may cause the driver to feel uncomfortable. Furthermore, even if a point a predetermined distance before the stationary target is set as the target position Xtrg, when the host vehicle 1 approaches very close to the target position Xtrg (for example, due to depression of the accelerator pedal), a similar phenomenon occurs if the relative speed Vr exceeds the speed profiles P1 and P2.

[0026] For this reason, the first speed profile P1 is set so that the predetermined set speed Vs is reached at a first point Xo1 that is closer to the host vehicle 1 than the target position Xtrg by a first distance D1. This makes it possible to increase the difference (V2-V1) between the second target speed V2 and the first target speed V1 in the immediate vicinity of the target position Xtrg compared to the first speed profile P1 shown in Fig. 4. This makes it possible to suppress large fluctuations in the braking / driving torque of the host vehicle 1 when the host vehicle 1 approaches the immediate vicinity of the target position Xtrg.

[0027] The first velocity profile P1 in FIG. 3 is a velocity profile (2×G1×Xr) 1 / 2 Although +Vs was obtained by offsetting it downward in the profile characteristic diagram of FIG. 3, the first velocity profile P1 may also be obtained by offsetting it rightward. For example, as shown in Figure 5(a), the velocity profile (2 × G1 × Xr) 1 / 2 The first velocity profile P1 may be obtained by offsetting +Vs to the right by a first distance D1 and limiting the lower limit by the set velocity Vs. For example, the controller 15 may calculate the first target speed V1 based on the following equation (3).

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[0028] Comparing the first speed profile P1 in Figure 5(a) with the first speed profile P1 in Figure 5(b), if the slopes of the first speed profile P1 in Figure 5(a) and Figure 5(b) at the first point Xo1 are α1 and α2, respectively, the slope α2 is smaller than the slope α1. Therefore, the first speed profile in Figure 5(b) has a smaller change in the first target speed V1 when the vehicle 1 passes the first point Xo1 than the first speed profile P1 in Figure 5(a), and fluctuations in the correction torque Tc can be suppressed.

[0029] Next, the function of the controller 15 will be described in more detail. Fig. 6 is a block diagram showing an example of the functional configuration of the controller 15. The controller 15 includes a basic braking / driving torque setting unit 30, a target position setting unit 31, a rate limiter 32, a correction torque setting unit 33, and a subtractor 34. The basic braking / driving torque setting unit 30 sets the basic braking / driving torque Tb in accordance with the accelerator pedal operation amount Ac and the vehicle speed V of the host vehicle 1 detected by the vehicle speed sensor. For example, as shown in the characteristic line in Fig. 2, when the accelerator pedal operation amount Ac is greater than a predetermined threshold Ac0, the basic braking / driving torque Tb may be set to a driving torque that increases as the operation amount Ac increases in accordance with the difference between the operation amount Ac and the threshold Ac0. When the accelerator pedal operation amount Ac is smaller than the predetermined threshold Ac0, the basic braking / driving torque Tb may be set to a braking torque that increases as the operation amount Ac decreases in accordance with the difference between the operation amount Ac and the threshold Ac0. Furthermore, the basic braking / driving torque setting unit 30 increases the slope of the basic braking / driving torque Tb as the vehicle speed V of the host vehicle 1 increases, and decreases the slope of the basic braking / driving torque Tb as the vehicle speed V of the host vehicle 1 decreases.

[0030] See Fig. 6. The target position setting unit 31 sets a target position Xtrg, which is a position where the relative speed Vr of the host vehicle 1 is set to a set speed Vs with respect to a stationary target or moving object ahead in the traveling direction of the host vehicle 1. For example, the target position setting unit 31 detects a stationary target such as a stop line or a stationary object that exists ahead in the traveling direction of the host vehicle 1 based on map information in the map DB 12 and surrounding environment information from the external sensor 13. The target position setting unit 31 sets a point a predetermined distance before the stationary target as the target position Xtrg. Further, for example, the target position setting unit 31 detects a moving object present ahead in the traveling direction of the vehicle 1 based on the surrounding environment information from the external sensor 13. The target position setting unit 31 sets a point a predetermined distance before the stationary target as the target position Xtrg. The target position setting unit 31 detects the relative distance Xr between the current position of the host vehicle 1 and the target position Xtrg, and the relative speed Vr of the host vehicle 1 with respect to the target position Xtrg. When the target position Xtrg is set with respect to a stationary target, the relative speed Vr becomes the current vehicle speed V of the host vehicle 1, and when the target position Xtrg is set with respect to a moving object, the relative speed Vr becomes the current relative speed of the host vehicle 1 with respect to the moving object.

[0031] The rate limiter 32 limits the speed change of the relative distance Xr output from the target position setting unit 31 and outputs the result to the correction torque setting unit 33. In this way, when the target position Xtrg changes, the rate of change is limited. The correction torque setting unit 33 sets a correction torque Tc based on the relative speed Vr detected by the target position setting unit 31 and the relative distance Xr whose speed change is limited by the rate limiter 32. The correction torque Tc will be described later. Subtractor 34 calculates torque command value Tf by subtracting correction torque Tc from basic braking / driving torque Tb calculated by basic braking / driving torque setting unit 30. Subtractor 34 outputs the calculated torque command value Tf to braking / driving force generation mechanism 16.

[0032] 7 is a block diagram showing an example of the functional configuration of the correction torque setting unit 33 according to the first embodiment. The correction torque setting unit 33 includes a first target speed calculation unit 40a, a second target speed calculation unit 40b, a first correction unit 41a, a ratio calculation unit 42, a limiter 43, and a gain multiplication unit 44. The first target speed calculation unit 40a and the first correction unit 41a calculate a first target speed V1, which is a target value for the vehicle speed V of the host vehicle 1, based on the first speed profile P1 and the relative distance Xr. At this time, the first target speed calculation unit 40a calculates an initial value V1b of the first target speed V1 based on the following equation (4). V1b=(2×G1×Xr) 1 / 2 +Vs…(4)

[0033] When the difference obtained by subtracting the first offset speed Vo1 from the initial value V1b is equal to or greater than the set speed Vs, the first correction unit 41a subtracts the first offset speed Vo1 from the initial value V1b to calculate the first target speed V1=V1b-Vo1. On the other hand, when the difference obtained by subtracting the first offset speed Vo1 from the initial value V1b is less than the set speed Vs, the first correction unit 41a sets the value of the first target speed V1 to the set speed Vs. In other words, the lower limit of the first target speed V1 is limited by the set speed Vs. In this way, the first correction unit 41a calculates the first target speed V1 of the above equation (1). The second target speed calculation unit 40b calculates the second target speed V2 based on the above equation (2).

[0034] The ratio calculation unit 42 calculates the ratio (Vr-V1) / (V2-V1) of the speed difference (Vr-V1) between the relative speed Vr and the first target speed V1 to the speed difference (V2-V1) between the second target speed V2 and the first target speed V1 as the correction coefficient α. The limiter 43 limits the correction coefficient α calculated by the ratio calculation unit 42 to a value within a range of a lower limit value αmin or more and an upper limit value αmax or less. The lower limit value αmin is set to a value equal to or greater than 0. This makes it possible to stop the output of the correction torque Tc when the relative speed Vr is equal to or less than the first target speed V1. For example, the lower limit value αmin may be set to "0."

[0035] The upper limit value αmax may be set appropriately depending on the maximum allowable value of the correction torque Tc that corrects and decreases the basic braking / driving torque Tb. For example, the upper limit value αmax may be set to "2". A gain multiplication unit 44 multiplies the correction coefficient α limited by the limiter 43 by an adjustment gain K1 to calculate the product as the correction torque Tc. The value of the adjustment gain K1 may be fixed, or may be an adjustment gain K1 that corresponds to the relative distance Xr, as in the first embodiment. This also applies to second to fourth embodiments described below.

[0036] Therefore, when the relative speed Vr is equal to or less than the first target speed V1, the value of the correction torque Tc is set to "0." When the relative speed Vr is greater than the first target speed V1 and equal to or less than the second target speed V2, the value of the correction torque Tc is set to K1×(Vr−V1) / (V2−V1). When the relative speed Vr is greater than the second target speed V2, the value of the correction torque Tc is set to K1×(Vr−V1) / (V2−V1) until it is limited by the upper limit value K1×αmax.

[0037] 3, as the host vehicle 1 approaches the target position Xtrg, the speed difference (V2-V1) between the second target speed V2 and the first target speed V1 becomes smaller and the correction coefficient α becomes larger. Therefore, as the host vehicle 1 approaches the target position Xtrg, the basic braking / driving torque Tb can be reduced and corrected with a larger correction torque Tc. Furthermore, when the relative speed Vr of the host vehicle changes from the first target speed V1 based on the first speed profile P1 to the second target speed V2 based on the second speed profile P2, the correction coefficient α changes from "0" to "1." Therefore, the value of the correction torque Tc can be set to "0" until the relative speed Vr exceeds the first speed profile P1. On the other hand, when the relative speed Vr exceeds the first speed profile P1, the correction torque Tc increases as the relative speed Vr increases, and when the relative speed Vr reaches the second target speed V2, the value of the correction torque Tc becomes "K1". Therefore, by appropriately setting the adjustment gain K1, it is possible to arbitrarily set the value of the correction torque Tc when the relative speed Vr reaches the second target speed V2 on the second speed profile P2.

[0038] (operation) FIG. 6 is a flowchart of an example of the braking / driving force control method according to the first embodiment. In step S1, the basic braking / driving torque setting unit 30 sets the basic braking / driving torque Tb. In step S2, the target position setting unit 31 sets the target position Xtrg. In step S3, the target position setting unit 31 calculates the relative distance Xr between the host vehicle 1 and the target position Xtrg. In step S4, the first target speed calculation unit 40a and the first correction unit 41a of the correction torque setting unit 33 calculate the first target speed V1 based on the first speed profile P1 and the relative distance Xr. In step S5, the second target speed calculation unit 40b of the correction torque setting unit 33 calculates the second target speed V2 based on the second speed profile P2 and the relative distance Xr.

[0039] In step S6, the target position setting unit 31 detects the relative speed Vr of the host vehicle 1 with respect to the target position Xtrg. In step S7, the correction torque setting unit 33 calculates the correction torque Tc based on the relative speed Vr, the first target speed V1, and the second target speed V2. In step S8, the subtractor 34 calculates the torque command value Tf by subtracting the correction torque Tc from the basic braking / driving torque Tb. In step S9, the braking / driving force generation mechanism 16 generates, in accordance with the torque command value Tf, a driving torque for driving the host vehicle 1 or a braking torque for braking the host vehicle 1. Then, the process ends.

[0040] (Second embodiment) 9 is a block diagram showing an example of the functional configuration of the correction torque setting unit 33 of the second embodiment. The correction torque setting unit 33 of the second embodiment has a configuration similar to that of the correction torque setting unit 33 of the first embodiment, and the same or similar components are denoted by the same reference numerals. The correction torque setting unit 33 of the second embodiment includes a third target speed calculation unit 40c, a second correction unit 41b, a switching unit 45, and an adder . The third target speed calculation unit 40c and the second correction unit 41b calculate the third target speed V3 based on the relative distance Xr and a third speed profile P3 indicating the vehicle speed according to the distance to the target position Xtrg. The third speed profile P3 decelerates at a third deceleration G3 that is smaller than the first deceleration G1, reaches the set speed Vs at a second point Xo2 that is closer to the vehicle 1 than the target position Xtrg by a second distance D2 that is longer than the first distance D1, and maintains the set speed Vs from the second point Xo2 to the target position Xtrg.

[0041] For example, the third speed profile P3 may be set as a calculation formula for the third target speed V3 using the relative distance Xr as a variable. For example, the third target speed calculation unit 40c and the second correction unit 41b may calculate the third target speed V3 based on the following formula (5).

number

[0042] Therefore, the third target speed calculation unit 40c calculates an initial value V3b of the third target speed V3 based on the following equation (6). V3b=(2×G3×Xr) 1 / 2 +Vs…(6) When the difference obtained by subtracting the second offset speed Vo2 from the initial value V3b is equal to or greater than the set speed Vs, the second correction unit 41b subtracts the second offset speed Vo2 from the initial value V3b to calculate the third target speed V3 = V3b - Vo2. On the other hand, when the difference obtained by subtracting the second offset speed Vo2 from the initial value V3b is less than the set speed Vs, the value of the third target speed V3 is set to the set speed Vs. In other words, the lower limit of the third target speed V3 is limited by the set speed Vs. In this way, the first correction unit 41a calculates the third target speed V3 using the above equation (5).

[0043] On the other hand, the first target speed calculation unit 40a and the first correction unit 41a calculate a first target speed V1, which is a target value for the vehicle speed V of the host vehicle 1, based on the first speed profile P1 and the relative distance Xr. Furthermore, the second target speed calculation unit 40b calculates a second target speed V2 based on the second speed profile P2 and the relative distance Xr. FIG. 10 shows examples of a first speed profile P1, a second speed profile P2, and a third speed profile P3 of the second embodiment. In the second embodiment, the deceleration G1 of the first speed profile P1 may be set to a value equivalent to the deceleration during relatively strong braking in everyday driving (e.g., 0.2 G), the deceleration G2 of the second speed profile P2 may be set to a value equivalent to or greater than the deceleration during sudden braking to prevent a rear-end collision (e.g., 0.3 G), and the deceleration G3 of the third speed profile P3 may be set to a value equivalent to or less than the deceleration during relatively weak braking in everyday driving (e.g., 0.1 G).

[0044] The ratio calculation unit 42 of the second embodiment receives the relative speed Vr, the first input speed VL, and the second input speed VH as inputs. The ratio calculation unit 42 calculates the correction coefficient α as the ratio (Vr-VL) / (VH-VL) of the speed difference (Vr-VL) between the relative speed Vr and the first input speed VL to the speed difference (VH-VL) between the second input speed VH and the first input speed VL. The switching unit 45 switches the first input speed VL input to the ratio calculation unit 42 between the first target speed V1 and the third target speed V3 depending on whether the relative speed Vr is greater than the first target speed V1. Also, the switching unit 45 switches the second input speed VH input to the ratio calculation unit 42 between the second target speed V2 and the first target speed V1 depending on whether the relative speed Vr is greater than the first target speed V1.

[0045] Specifically, when the relative speed Vr is equal to or less than the first target speed V1, the switching unit 45 inputs the third target speed V3 and the first target speed V1 as the first input speed VL and the second input speed VH, respectively, to the ratio calculation unit 42. In this case, the ratio calculation unit 42 calculates the correction coefficient α as the ratio (Vr-V3) / (V1-V3) of the speed difference (Vr-V3) between the relative speed Vr and the third target speed V3 to the speed difference (V1-V3) between the first target speed V1 and the third target speed V3. When the relative speed Vr is greater than the first target speed V1, the switching unit 45 inputs the first target speed V1 and the second target speed V2 as the first input speed VL and the second input speed VH, respectively, to the ratio calculation unit 42. In this case, the ratio calculation unit 42 calculates, as the correction coefficient α, the ratio (Vr-V1) / (V2-V1) of the speed difference (Vr-V1) between the relative speed Vr and the first target speed V1 to the speed difference (V2-V1) between the second target speed V2 and the first target speed V1.

[0046] Furthermore, when the relative speed Vr is greater than the first target speed V1, the switching unit 45 sets the value of the offset value Offset that offsets the correction coefficient α to "1." When the relative speed Vr is equal to or less than the first target speed V1, the switching unit 45 sets the value of the offset value Offset to "0." The function of the limiter 43 in the second embodiment is similar to the function of the limiter 43 in the first embodiment. The adder 46 adds the offset value Offset to the correction coefficient α limited by the limiter 43 to obtain a sum (α+Offset), and inputs the sum to the gain multiplication unit 44. The gain multiplication unit 44 multiplies the sum (α+Offset) by the adjustment gain K1 to calculate the product K1×(α+Offset) as the correction torque Tc.

[0047] Therefore, when the relative speed Vr is equal to or less than the third target speed V3, the value of the correction torque Tc is set to "0." When the relative speed Vr is greater than the third target speed V3 and equal to or less than the first target speed V1, the value of the correction torque Tc is set to K1 × (Vr - V3) / (V1 - V3). When the relative speed Vr is greater than the first target speed V1 and equal to or less than the second target speed V2, the value of the correction torque Tc is set to K1 × ((Vr - V1) / (V2 - V1) + 1). When the relative speed Vr is greater than the second target speed V2, the value of the correction torque Tc is set to K1 × ((Vr - V1) / (V2 - V1) + 1) until it is limited by the upper limit value K1 × (αmax + 1). In the configuration example of FIG. 9, the adder 46 is provided after the limiter 43, but it may be provided between the ratio calculation unit 42 and the limiter 43 instead.

[0048] 10, the closer the host vehicle 1 is to the target position Xtrg, the smaller the speed difference (V1-V3) between the first target speed V1 and the third target speed V3 becomes. Also, the speed difference (V2-V1) between the second target speed V2 and the first target speed V1 becomes smaller. Therefore, the closer the host vehicle 1 is to the target position Xtrg, the larger the correction coefficient α becomes, and the basic braking / driving torque Tb can be reduced / corrected by a large correction torque Tc. Furthermore, the value of the correction torque Tc can be set to "0" until the relative speed Vr exceeds the third speed profile P3. Furthermore, by appropriately setting the adjustment gain K1, the correction torque Tc when the relative speed Vr reaches the first target speed V1 on the first speed profile P1 can be set to an arbitrary value "K1."

[0049] Furthermore, when the relative speed Vr of the host vehicle changes from the first target speed V1 based on the first speed profile P1 to the second target speed V2 based on the second speed profile P2, the sum of the correction coefficient α and the offset value Offset (α+Offset) changes from "1" to "2". Therefore, by appropriately setting the adjustment gain K1, the correction torque Tc when the relative speed Vr reaches the second target speed V2 on the second speed profile P2 can be set to an arbitrary value "2 x K1".

[0050] (Third embodiment) 11 is a block diagram showing an example of the functional configuration of the correction torque setting unit 33 of the third embodiment. The difference between the correction torque setting unit 33 of the third embodiment and the correction torque setting unit 33 of the second embodiment is that a first correction unit 41a sets a first distance D1 in accordance with the relative distance Xr and the speed Vf of the moving body, and a second correction unit 41b sets a second distance D2 in accordance with the relative distance Xr and the speed Vf of the moving body.

[0051] 4, if the first speed profile P1 is set so that the predetermined set speed Vs is reached at the target position Xtrg, when the host vehicle 1 approaches very close to the target position Xtrg, the denominator (V2-V1) of the ratio (Vr-V1) / (V2-V1) approaches 0, causing a large change in the correction torque Tc, which may result in large fluctuations in the braking / driving torque of the host vehicle 1. The same applies when the third speed profile P3 is set so that the predetermined set speed Vs is reached at the target position Xtrg. For this reason, the first correction unit 41a sets the first speed profile P1 so that the set speed Vs is reached at a first point Xo1 that is closer to the host vehicle 1 than the target position Xtrg by a first distance D1. Similarly, the second correction unit 41b sets the third speed profile P3 so that the predetermined set speed Vs is reached at a second point Xo2 that is closer to the host vehicle 1 than the target position Xtrg by a second distance D2.

[0052] However, when the host vehicle 1 is sufficiently far from the target position Xtrg (i.e., the relative distance Xr is long), the change in the correction torque Tc is not large, so it is not necessary to set the speed profile so that the set speed Vs is reached at a point closer to the host vehicle 1 than the target position Xtrg. In fact, if the speed profile is set so that the set speed Vs is reached at a point closer to the host vehicle 1 than the target position Xtrg, the braking / driving torque is corrected so that the vehicle speed V of the host vehicle 1 reaches the set speed Vs before the target position Xtrg, which may cause the vehicle speed V of the host vehicle 1 to reach the set speed Vs unnecessarily early. For example, if the set speed Vs is 0, there is a risk that the host vehicle 1 will come to a stop before the target position Xtrg. Therefore, the first corrector 41a and the second corrector 41b make the first distance D1 and the second distance D2 shorter when the relative distance Xr is long than when it is short.

[0053] Furthermore, as explained with reference to FIG. 4, when a point in front of the moving body is set as the target position Xtrg, fluctuations in the moving body speed Vf make it easier for the relative speed Vr to exceed the speed profile, and when the relative distance Xr is short, the braking / driving torque fluctuates greatly, which may cause the driver to feel uncomfortable. Therefore, the first corrector 41a and the second corrector 41b make the first distance D1 and the second distance D2 longer when the speed Vf of the moving body is high than when it is low.

[0054] For example, the first corrector 41a may set the first offset speed Vo1 based on the following equation (7). Vo1=K2a×(2×G1×Vf×T) 1 / 2 …(7) According to the above formula (7), the higher the speed Vf, the larger the first offset speed Vo1 becomes, and the longer the first distance D1 becomes. In the above equation (7), K2a is a relative velocity sensitive gain that is set in accordance with the relative distance Xr. The first corrector 41a reduces the relative velocity sensitive gain K2a when the relative distance Xr is long compared to when it is short, thereby shortening the first distance D1 when the relative distance Xr is long compared to when it is short. 12 is a diagram showing an example of the characteristics of the relative velocity sensitive gain K2a. For example, when the relative distance Xr is in the range of 0 to d0a, the relative velocity sensitive gain K2a is 1. When the relative distance Xr is in the range of d0a or more, the relative velocity sensitive gain K2a decreases as the relative distance Xr increases. As a result, the first distance D1 becomes shorter as the relative distance Xr becomes longer.

[0055] On the other hand, the second corrector 41b may set the second offset speed Vo2 based on the following equation (8). Vo2=K2b×(2×G3×Vf×T) 1 / 2 …(8) According to the above formula (8), the higher the speed Vf, the larger the second offset speed Vo2 becomes, and the longer the second distance D2 becomes. In the above equation (8), K2b is a relative velocity sensitive gain that is set according to the relative distance Xr. The characteristics of the relative velocity sensitive gain K2b may be the same as or similar to the characteristics of the relative velocity sensitive gain K2a described with reference to FIG.

[0056] Note that when the basic braking / driving torque Tb corresponding to the accelerator pedal operation amount Ac is corrected by the correction torque Tc (i.e., when the relative distance Xr exceeds the third speed profile P3 and the correction torque Tc is not 0), the first correction unit 41a and the second correction unit 41b may stop setting the first offset speed Vo1 according to the above equation (7) and the second offset speed Vo2 according to the above equation (8) and may retain the values ​​of the first offset speed Vo1 and the second offset speed Vo2. This makes it possible to prevent the occurrence of a sudden deceleration of the host vehicle 1 due to a sudden change in the correction torque Tc caused by changing the first speed profile P1 or the third speed profile P3 during correction based on the correction torque Tc.

[0057] In the above third embodiment, an example was described in which, in a configuration in which the first to third speed profiles P1 to P3 are set, the first correction unit 41a and the second correction unit 41b set the first distance D1 and the second distance D2 according to the relative distance Xr and the speed Vf of the moving body. However, in a configuration in which the first and second speed profiles P1 and P3 are set as in the first embodiment, the first correction unit 41a may similarly set the first distance D1 according to the relative distance Xr and the speed Vf of the moving body.

[0058] (Fourth embodiment) As described above, when the target position Xtrg is set in front of a moving body in the direction of travel of the vehicle 1, the vehicle 1 is decelerated based on a speed profile in which the relative speed Vr with respect to the moving body becomes the set speed Vs at the target position Xtrg. For this reason, when the moving body is decelerating, it may not be possible to set the relative velocity Vr to the set velocity Vs at the target position Xtrg. Therefore, the correction torque setting unit 33 of the fourth embodiment increases the correction torque Tc when the moving body is decelerating. Specifically, the acceleration a of a moving object detected ahead in the traveling direction of the host vehicle 1 is detected, and the larger the detected acceleration a, the smaller the correction torque Tc. In other words, the larger the deceleration, which is the acceleration with a negative value, the larger the correction torque Tc.

[0059] Fig. 13 is a block diagram showing an example of the functional configuration of the correction torque setting unit 33 of the fourth embodiment. The correction torque setting unit 33 of the fourth embodiment has a configuration similar to that of the correction torque setting unit 33 of the third embodiment described with reference to Fig. 11, and the same components are denoted by the same reference numerals. The correction torque setting unit 33 of the fourth embodiment includes an acceleration calculation unit 47, a gain multiplication unit 48, and an adder 49.

[0060] When a point a predetermined distance before a moving body in front of the vehicle in the direction of travel is set as the target position Xtrg, the acceleration calculation unit 47 calculates the relative acceleration of the moving body with respect to the vehicle 1 by differentiating the relative speed Vr. The acceleration calculation unit 47 may calculate the acceleration of the moving body by differentiating the velocity Vf of the moving body. Hereinafter, the relative acceleration calculated by the acceleration calculation unit 47 or the acceleration of the moving body may be collectively referred to as "acceleration a."

[0061] The gain multiplication unit 48 multiplies the acceleration a calculated by the acceleration calculation unit 47 by a negative adjustment gain K3 to calculate the product as the second correction torque Tc2. Therefore, when the acceleration a indicates deceleration (i.e., when the acceleration a is less than 0), the second correction torque Tc2 has a positive value. For example, the adjustment gain K3 may be a negative gain whose absolute value is larger when the relative distance Xr is short than when it is long. For example, the adjustment gain K3 may be a negative gain whose absolute value is larger as the relative distance Xr is shorter. This allows the basic braking / driving torque Tb to be reduced and corrected by a larger second correction torque Tc2 as the host vehicle 1 approaches the target position Xtrg.

[0062] The gain multiplication unit 44 multiplies the sum (α+Offset) of the correction coefficient α limited by the limiter 43 and the offset value Offset by the adjustment gain K1, and calculates the product as the first correction torque Tc1. The adder 49 calculates the sum of the first correction torque Tc1 and the second correction torque Tc2 as the correction torque Tc, and outputs it to the subtractor 34 shown in FIG. Similarly, an acceleration calculation section 47, a gain multiplication section 48, and an adder 49 may be added to the correction torque setting section 33 of the first and second embodiments.

[0063] (Effects of the embodiment) (1) The controller 15 calculates a braking / driving force according to the amount of operation of the accelerator pedal of the host vehicle 1, calculates a relative distance between the current position of the host vehicle 1 and a target position which is a predetermined position set ahead in the traveling direction of the host vehicle, calculates a first target speed based on the relative distance and a first speed profile which indicates a vehicle speed according to the distance to the target position, the first speed profile being decelerated at a first deceleration to reach a predetermined set speed at a first point which is closer to the host vehicle 1 by a first distance than the target position, and maintains the set speed from the first point to the target position, and the relative distance, and calculates a first target speed based on the first speed profile which is set as a speed profile according to the distance to the target position and A second target speed is calculated based on a second speed profile in which the vehicle is decelerated at a second deceleration greater than the first deceleration to reach a set speed at the target position, and based on the relative distance; the relative speed of the vehicle (1) with respect to the target position is detected; if the relative speed is equal to or greater than the first target speed, a larger correction amount is calculated the greater the ratio of the difference obtained by subtracting the first target speed from the relative speed divided by the difference obtained by subtracting the first target speed from the second target speed; corrected braking / driving forces are calculated by subtracting the correction amount from the braking / driving forces calculated in accordance with the amount of operation of the accelerator pedal; and the braking / driving forces of the vehicle (1) are controlled based on the calculated corrected braking / driving forces. This reduces the sense of discomfort felt by the driver when decelerating the host vehicle 1 based on the first speed profile. Also, while the braking / driving force can be reduced by a larger correction amount as the host vehicle 1 approaches the target position, it is possible to suppress large fluctuations in the braking / driving torque of the host vehicle 1 due to a large change in the correction torque Tc when the host vehicle 1 approaches very close to the target position. Furthermore, the value of the correction amount can be set to "0" until the relative velocity exceeds the first velocity profile. On the other hand, when the relative velocity exceeds the first velocity profile, the correction amount is increased as the difference between the relative velocity and the first target velocity increases, and the value of the correction amount when the relative velocity reaches the second target velocity on the second velocity profile can be set arbitrarily.

[0064] (2) The controller 15 calculates a third target speed based on a third speed profile indicating the vehicle speed according to the distance to the target position, in which the vehicle decelerates at a third deceleration smaller than the first deceleration, reaches the set speed at a second point that is closer to the vehicle 1 than the target position by a second distance that is longer than the first distance, and maintains the set speed from the second point to the target position, and based on the relative distance; and when the relative speed is equal to or greater than the third target speed, the controller 15 may calculate a larger correction amount as the ratio of the difference obtained by subtracting the third target speed from the relative speed divided by the difference obtained by subtracting the third target speed from the first target speed increases. This allows the value of the correction amount to be set to "0" until the relative velocity exceeds the third velocity profile. On the other hand, when the relative velocity exceeds the third velocity profile, the correction amount is increased as the difference between the relative velocity and the third target velocity increases, and the value of the correction amount when the relative velocity reaches the first target velocity on the first velocity profile can be set arbitrarily. Furthermore, when the relative velocity exceeds the first velocity profile, the correction amount is increased as the difference between the relative velocity and the first target velocity increases, and the value of the correction amount when the relative velocity reaches the second target velocity on the second velocity profile can be set arbitrarily.

[0065] (3) The controller 15 may acquire the first speed profile by reducing the speed of a speed profile that indicates a vehicle speed according to the distance to the target position and that decelerates at a first deceleration to reach a set speed at the target position by the first speed and by limiting the lower limit value to the set speed. This makes it possible to set a first speed profile that decelerates at the first deceleration to reach a predetermined set speed at a first point that is closer to the host vehicle 1 than the target position by the first distance and maintains the set speed from the first point to the target position.

[0066] (4) The controller 15 may acquire the third speed profile by reducing the speed of the speed profile, which indicates the vehicle speed according to the distance to the target position and which decelerates at a third deceleration to reach the set speed at the target position, by a second speed higher than the first speed and by limiting the lower limit value to the set speed. This makes it possible to set the third speed profile, which decelerates at the third deceleration to reach the set speed at a second point closer to the target position than the host vehicle 1 by a second distance longer than the first distance, and maintains the set speed from the second point to the target position.

[0067] (5) Controller 15 may shorten the first distance when the relative distance is long compared to when the relative distance is short. This makes it possible to prevent the braking / driving force from being controlled so that the vehicle speed of host vehicle 1 reaches the set speed before the target position when host vehicle 1 is sufficiently far from the target position and there is little risk of a large fluctuation in the correction amount occurring when host vehicle 1 approaches very close to the target position. (6) Controller 15 may maintain the first distance regardless of changes in the relative distance if the correction amount is not 0. This prevents the first speed profile from being changed during correction of the braking / driving force, thereby preventing sudden deceleration of host vehicle 1.

[0068] (7) The controller 15 may limit the rate of change of the target position, thereby preventing a sudden change in the braking / driving force due to a sudden change in the target position. (8) The controller 15 may set a point a predetermined distance before the position of a stationary target ahead of the host vehicle 1 as the target position for stopping the host vehicle 1. This allows the host vehicle 1 to decelerate so that the host vehicle 1 can stop in front of the stationary target ahead of the host vehicle 1. (9) The controller 15 may set as the target position a point a predetermined distance before the position of a moving object ahead of the host vehicle 1. This allows the host vehicle 1 to decelerate before the moving object ahead of the host vehicle 1 so that the relative speed between the host vehicle 1 and the moving object becomes the set speed.

[0069] (10) The controller 15 may set a point a predetermined distance before the position of a moving body ahead of the host vehicle 1 as the target position, detect the speed of the moving body in the traveling direction of the host vehicle 1, and make the first distance longer when the detected speed is faster than when it is slow. This prevents the relative speed from exceeding the first speed profile even when the moving body ahead of the host vehicle 1 moves, thereby preventing large fluctuations in the correction amount even when the host vehicle 1 approaches very close to the target position. (11) Controller 15 may maintain the first distance regardless of changes in speed if the correction amount is not 0. This prevents the first speed profile from being changed during correction of the braking / driving force, thereby preventing sudden deceleration of host vehicle 1.

[0070] (12) The controller 15 may detect the acceleration of the moving object in the traveling direction of the host vehicle 1, and may decrease the correction amount as the detected acceleration increases. Alternatively, the controller 15 may detect the relative acceleration of the moving object with respect to the host vehicle 1 in the traveling direction of the host vehicle 1, and may decrease the correction amount as the detected relative acceleration increases. This makes it easier to control the relative speed between the vehicle 1 and the moving body to the set speed at the target position in front of the moving body, even if the moving body is decelerating. [Explanation of symbols]

[0071] 1... host vehicle, 2... preceding vehicle, 10... braking / driving force control device, 11... positioning device, 12... map database (map DB), 13... external sensor, 14... vehicle sensor, 15... controller, 16... braking / driving force generation mechanism, 20... processor, 21... storage device, 30... basic braking / driving torque setting unit, 31... target position setting unit, 32... rate limiter, 33... correction torque setting unit, 34... subtractor, 40a... first target speed calculation unit, 40b... second target speed calculation unit, 40c... third target speed calculation unit, 41a... first correction unit, 41b... second correction unit, 42... ratio calculation unit, 43... limiter, 44, 48... gain multiplication unit, 45... switching unit, 46, 49... adder, 47... acceleration calculation unit

Claims

1. Calculating braking / driving force according to the amount of accelerator pedal operation of the vehicle; setting a position ahead of the host vehicle in a traveling direction where the host vehicle is to be stopped, or a point a predetermined distance before a moving object ahead of the host vehicle, as a target position; Calculating a relative distance between the current position of the vehicle and the target position; calculating a first target speed based on a first speed profile indicating a vehicle speed according to a distance to the target position, the first speed profile being one in which the host vehicle decelerates at a first deceleration to reach a predetermined set speed at a first point that is closer to the host vehicle than the target position by a first distance, and the set speed being maintained from the first point to the target position, and the relative distance; calculating a second target velocity based on the relative distance and a second velocity profile that is set as a velocity profile according to the distance to the target position and that decelerates at a second deceleration that is greater than the first deceleration to reach the set velocity at the target position; Detecting a relative speed of the host vehicle with respect to the target position; when the relative speed is equal to or greater than the first target speed, the larger the ratio of the difference obtained by subtracting the first target speed from the relative speed divided by the difference obtained by subtracting the first target speed from the second target speed, the larger the correction amount calculated; calculating corrected braking / driving forces by subtracting the correction amount from the braking / driving forces calculated in accordance with the accelerator pedal depression amount; controlling the braking / driving force of the host vehicle based on the calculated corrected braking / driving force; A braking / driving force control method characterized by the above.

2. calculating a third target speed based on the relative distance and a third speed profile indicating a vehicle speed according to a distance to the target position, the third speed profile being one in which the host vehicle decelerates at a third deceleration smaller than the first deceleration, reaches the set speed at a second point closer to the host vehicle than the target position by a second distance longer than the first distance, and maintains the set speed from the second point to the target position; When the relative speed is equal to or greater than the third target speed, the larger the ratio of the difference obtained by subtracting the third target speed from the relative speed divided by the difference obtained by subtracting the third target speed from the first target speed, the larger the correction amount calculated.

2. The braking / driving force control method according to claim 1.

3. 3. The braking / driving force control method according to claim 1, wherein the first speed profile is acquired by reducing the speed of a speed profile that indicates a vehicle speed according to a distance to the target position and that decelerates at the first deceleration to reach the set speed at the target position by the first speed and limiting a lower limit value to the set speed.

4. 3. The braking / driving force control method according to claim 2, wherein the first speed profile is acquired by reducing a speed of a speed profile that indicates a vehicle speed corresponding to the distance to the target position and that decelerates at the first deceleration to reach the set speed at the target position by a first speed and limiting a lower limit value at the set speed, and the third speed profile is acquired by reducing a speed of a speed profile that indicates a vehicle speed corresponding to the distance to the target position and that decelerates at the third deceleration to reach the set speed at the target position by a second speed that is higher than the first speed and limiting a lower limit value at the set speed.

5. 5. The braking / driving force control method according to claim 1, wherein the first distance is made shorter when the relative distance is long than when the relative distance is short.

6. 6. The braking / driving force control method according to claim 5, wherein when the correction amount is not zero, the first distance is maintained regardless of changes in the relative distance.

7. 7. The braking / driving force control method according to claim 1, wherein the rate of change of the target position is limited.

8. 8. The braking / driving force control method according to claim 1, wherein the target position is set to a stationary position that is a point a predetermined distance before the position of a stationary target ahead of the host vehicle.

9. The braking / driving force control method according to any one of claims 1 to 7, wherein a moving position that is a point a predetermined distance before the position of the moving body ahead of the host vehicle is set as the target position.

10. setting a moving position that is a point a predetermined distance before the position of the moving body ahead of the host vehicle as the target position; Detecting the speed of the moving object in the traveling direction of the host vehicle; 8. The braking / driving force control method according to claim 1, wherein the first distance is made longer when the detected speed is high than when the detected speed is low.

11. 11. The braking / driving force control method according to claim 10, wherein when the correction amount is not zero, the first distance is maintained regardless of changes in the speed.

12. detecting an acceleration of the moving object in a traveling direction of the host vehicle; The greater the detected acceleration, the smaller the correction amount.

12. The braking / driving force control method according to claim 9, wherein the braking / driving force control method is a braking / driving force control method.

13. Detecting a relative acceleration of the moving object with respect to the host vehicle in a traveling direction of the host vehicle; The larger the detected relative acceleration is, the smaller the correction amount is.

13. The braking / driving force control method according to claim 9, wherein the braking / driving force control method is a braking / driving force control method.

14. Accelerator pedal and a braking / driving force generation mechanism that generates braking / driving forces for the host vehicle; a braking / driving force corresponding to an operation amount of the accelerator pedal is calculated; a position ahead of the host vehicle in a traveling direction where the host vehicle is to be stopped, or a point a predetermined distance before a moving object ahead of the host vehicle, is set as a target position; a relative distance between the current position of the host vehicle and the target position is calculated; a first speed profile indicating a vehicle speed according to a distance to the target position, the first speed profile being a first speed profile that decelerates the host vehicle at a first deceleration to reach a predetermined set speed at a first point that is a first distance closer to the host vehicle than the target position, and the set speed is maintained from the first point to the target position; and a first target speed is calculated based on the relative distance; and the first target speed is set as a speed profile according to the distance to the target position; a controller that calculates a second target speed based on the relative distance and a second speed profile in which the host vehicle is decelerated at a second deceleration greater than the first deceleration to reach the set speed at the target position, detects the relative speed of the host vehicle with respect to the target position, and, when the relative speed is equal to or greater than the first target speed, calculates a larger correction amount the greater the ratio of a difference obtained by subtracting the first target speed from the relative speed divided by the difference obtained by subtracting the first target speed from the second target speed, calculates corrected braking / driving forces by subtracting the correction amount from the braking / driving forces calculated in accordance with the amount of operation of the accelerator pedal, and controls the braking / driving force generation mechanism based on the calculated corrected braking / driving forces; A braking / driving force control device comprising:

Images