JP6587803B2 - Vehicle travel control device and vehicle travel control method - Google Patents

Description

  The present invention relates to a vehicular travel control device and a vehicular travel control method for supporting travel of a vehicle entering a curved road.

  A recent vehicle is equipped with a device for supporting driving. This device provides the following driving assistance when entering a curved road. First, the distance between the vehicle and the curve start position is calculated using GPS and map information. A target vehicle speed suitable for curve driving is calculated according to the curve shape (curvature, etc.). The target deceleration is calculated from the target vehicle speed and the own vehicle speed. When the target deceleration is above a certain level and the accelerator pedal is being operated, a reaction force is generated on the accelerator pedal, and the driver is encouraged to lift the foot from the pedal. If the accelerator pedal is not operated and the target deceleration is equal to or greater than a certain value, an automatic brake calculated from the target deceleration is generated, and the host vehicle speed is reduced to the target vehicle speed.

  The reaction force of the accelerator pedal is disclosed in Patent Documents 1, 2, and 3. Patent documents 1, 2, and 3 disclose devices that control the reaction force of an accelerator pedal in accordance with the risk potential. The risk potential is calculated based on the inter-vehicle distance or relative speed between the host vehicle and the preceding vehicle. Furthermore, Patent Document 1 discloses a device that learns the driver's reaction and corrects the risk potential equation.

Japanese Patent No. 4003597 Japanese Patent No. 4131327 Japanese Patent No. 4367180

  The devices described in Patent Documents 1, 2, and 3 generate a reaction force on the accelerator pedal based on the risk potential, and do not generate a reaction force on the accelerator pedal when entering a curved road.

  There are the following problems with the technology for generating a reaction force on the accelerator pedal when entering a curved road. Since driving with respect to a curve varies greatly depending on the individual, the timing for starting deceleration with respect to the curve greatly depends on the individual. For this reason, when the timing of occurrence of the reaction force of the accelerator pedal set in advance is far from the individual feeling, for example, when the timing of the reaction force is early with respect to the driver who releases the accelerator pedal later, The reaction force may be disturbed. Moreover, when the timing of reaction force is late with respect to the driver who releases the accelerator pedal early, the driver may feel uncomfortable. If the timing at which the accelerator pedal is released is close to the timing at which the reaction force is generated, the driver can drive with a good rhythm and a sense of incompatibility.

  The present invention has been made in consideration of such a problem, and a vehicle travel control device capable of generating a reaction force of an accelerator pedal at an appropriate timing according to a driver before entering a curved road, and An object of the present invention is to provide a vehicle travel control method.

  The present invention includes a curve detection unit that detects a curved road ahead of a vehicle, a target vehicle speed calculation unit that calculates a target vehicle speed that is a target when the vehicle travels on a road including the curved road, and the target vehicle speed and the actual vehicle speed. In a vehicle travel control device that includes an accelerator pedal reaction force control unit that generates a reaction force on the accelerator pedal when there is a deviation, a deceleration that is performed by the driver when the reaction force is generated on the accelerator pedal Further comprising a reaction force timing learning unit that learns based on the operation timing, the accelerator pedal reaction force control unit based on the timing learned by the reaction force timing learning unit the timing at which the accelerator pedal generates the reaction force It is characterized by changing.

  In the present invention, before entering the curved road, the timing for generating the reaction force on the accelerator pedal is learned based on the timing of the deceleration operation performed by the driver. And based on the learned timing, the timing which generates reaction force to an accelerator pedal is changed. Thus, according to the present invention, since the driver learns the deceleration operation before entering the curved road, the subsequent reaction force control before entering the curved road can be appropriately performed according to the driver's preference. .

  The present invention further includes a necessary deceleration calculating unit that calculates a necessary deceleration required to obtain the target vehicle speed from an actual vehicle speed, and the accelerator pedal reaction force control unit is calculated by the necessary deceleration calculating unit. The reaction force is generated by the accelerator pedal at a timing when the required deceleration that has been made falls below a reaction force generation acceleration / deceleration threshold, and the reaction force timing learning unit is based on the timing of the deceleration operation performed by the driver, The reaction force generation acceleration / deceleration threshold value may be changed. According to the present invention, the timing of the reaction force generated in the accelerator pedal can be performed by changing the reaction force generation acceleration / deceleration threshold value.

  The present invention further includes an accelerator pedal operation detection unit that detects an operation of an accelerator pedal, and when the operation of the accelerator pedal is not detected by the accelerator pedal operation detection unit, the reaction force timing learning unit is connected to the accelerator pedal. The timing for generating the reaction force may not be learned. According to the present invention, learning accuracy is improved by not learning when the driver is not operating the accelerator pedal.

  In the present invention, when a predetermined deceleration operation is performed at least twice, the reaction force generation acceleration / deceleration threshold value is changed to another reaction force generation acceleration / deceleration threshold value lower than the reaction force generation acceleration / deceleration threshold value. May be. In a driving environment such as rainy weather or fog, the driver tends to decelerate early. In such a case, since the driver releases the accelerator pedal early, it is preferable to advance the timing of the reaction force generated in the accelerator pedal. According to the present invention, the reaction force generation acceleration / deceleration threshold value is changed according to the operation of the driver. For this reason, the generation timing of the reaction force generated in the accelerator pedal can be advanced.

  In the present invention, the reaction force timing learning unit may maintain the another reaction force generation acceleration / deceleration threshold until the vehicle drive source is turned off. Environments such as rain and fog often continue during a single run (vehicle drive source on to off), so another reaction force generation that is lower than the normal reaction force generation acceleration / deceleration threshold value When the speed threshold value is changed, it is desirable that the reaction force generation acceleration / deceleration threshold value after the change is maintained during one run (vehicle drive source on to off). According to the present invention, since another reaction force generation acceleration / deceleration threshold value is maintained until the vehicle drive source is turned off, the timing of the reaction force generated by the accelerator pedal can be made appropriate.

  The reaction force timing learning unit stores the reaction force generation acceleration / deceleration threshold before changing to the another reaction force generation acceleration / deceleration threshold, and is turned on after the vehicle drive source is turned off. In addition, the reaction force generation acceleration / deceleration threshold value may be restored. Environments such as rain and fog are unlikely to continue for a long period of time, so if you change to another reaction force generation acceleration / deceleration threshold value that is lower than the normal reaction force generation acceleration / deceleration threshold value, It is desirable to return to the reaction force generation acceleration / deceleration threshold value. According to the present invention, since the normal reaction force generation acceleration / deceleration threshold value is restored when the drive source is turned on next time, the timing of the reaction force generated by the accelerator pedal can be made appropriate.

  The present invention detects a curve road ahead of a vehicle, calculates a target vehicle speed that is a target when the vehicle travels on a road including the curve road, and an accelerator pedal when there is a difference between the target vehicle speed and the actual vehicle speed In the vehicle travel control method for generating a reaction force on the vehicle, the timing for generating the reaction force on the accelerator pedal is learned based on the timing of the deceleration operation performed by the driver, and the reaction to the accelerator pedal is determined based on the learned timing. It is characterized by generating force.

  The present invention calculates a necessary deceleration required to obtain the target vehicle speed from an actual vehicle speed, and causes the accelerator pedal to generate the reaction force at a timing when the necessary deceleration falls below a reaction force generation acceleration / deceleration threshold. Based on the timing of the deceleration operation performed by the driver, the reaction force generation acceleration / deceleration threshold value is changed, the reaction force is generated in the accelerator pedal, and the accelerator pedal is released before the reaction force reaches the maximum value. The reaction force generation acceleration / deceleration threshold value is not changed, and the reaction force is generated when the accelerator pedal is released after the reaction force is generated and the reaction force reaches the maximum value. When the generated acceleration / deceleration threshold is lowered and the timing to generate the reaction force on the accelerator pedal and the accelerator pedal is not operated, the reaction force generation acceleration / deceleration threshold is increased to automatically When the rake is operated and the brake pedal is operated, the reaction force generation acceleration / deceleration threshold is increased, and when the automatic brake is operated and the accelerator pedal is operated, the reaction force generation acceleration / deceleration threshold is decreased. Features.

  According to the present invention, since the deceleration operation performed by the driver before entering the curved road is learned, the subsequent reaction force control before entering the curved road can be appropriately performed according to the preference of the driver.

FIG. 1 is a block diagram of a vehicular travel control apparatus according to an embodiment of the present invention. FIG. 2A is a characteristic diagram showing the value of the reaction force applied to the accelerator pedal by the accelerator pedal reaction force applying unit with time. FIG. 2B is an explanatory diagram showing the relationship between the traveling road before the curve road and the necessary deceleration. FIG. 3 is a flowchart for explaining the normal learning initialization process. FIG. 4 is a flowchart for explaining the reaction force generation process. FIG. 5 is a flowchart for explaining the reaction force timing learning process (1). FIG. 6 is a flowchart for explaining the reaction force timing learning process (2). FIG. 7 is a flowchart for explaining the external environment learning initialization process. FIG. 8 is a flowchart for explaining the reaction force timing learning process (external environment).

  Hereinafter, preferred embodiments of the vehicle travel control apparatus 10 according to the present invention will be described in detail with reference to the accompanying drawings.

[Configuration of Traveling Control Device 10]
The vehicle travel control device 10 includes a map information acquisition unit 12, a vehicle speed detection unit 14, a brake pedal operation detection unit 16, an accelerator pedal operation detection unit 18, a drive source switch 20, a travel control unit 22, and a brake. A device 24 and an accelerator pedal reaction force applying unit 26 are provided.

  The map information acquisition unit 12 includes a device that acquires map information and information on the current position of the vehicle. For example, the vehicle position can be measured by radio wave navigation using a GPS receiver and autonomous navigation using a gyro sensor, a G sensor, and the like. It is also possible to provide a device such as a camera or radar that can acquire information outside the vehicle.

  The vehicle speed detection unit 14 includes a device that measures the vehicle speed V of the vehicle. For example, a plurality of wheel speed sensors that individually detect the rotation speeds of the wheels are provided, and the vehicle speed V is obtained based on the rotation speeds of the wheels detected by the plurality of wheel speed sensors.

  The brake pedal operation detection unit 16 includes a device that detects an operation amount of the brake pedal 36 operated by the driver. For example, a stroke sensor that detects the operation amount of the brake pedal 36, a hydraulic pressure sensor that detects the hydraulic pressure of the brake fluid, and the like are provided. The brake pedal operation detection unit 16 includes a brake switch 38.

  The accelerator pedal operation detection unit 18 includes a device that detects an operation amount of the accelerator pedal 40 operated by the driver. For example, an opening sensor that detects the opening of the accelerator pedal 40 is provided. The accelerator pedal 40 is provided with a hysteresis. For this reason, the accelerator on threshold value for the accelerator pedal operation detecting unit 18 to detect the on operation of the accelerator pedal 40 is different from the accelerator off threshold value for detecting the off operation of the accelerator pedal 40.

  The drive source switch 20 is a switch for switching on and off of a vehicle drive source (engine or electric motor). For example, an ignition switch and a start switch are provided.

  The traveling control unit 22 is configured by an on-vehicle ECU (electronic control unit). As is well known, the ECU is a computer including a microcomputer, a CPU (Central Processing Unit), a ROM (including EEPROM) as a memory, a RAM (Random Access Memory), other A / D converters, D / A converter and other input / output devices, a timer as a timekeeping unit, etc., and various function realization units (function realization means) such as a control unit when the CPU reads and executes a program recorded in the ROM , Functions as a calculation unit, a processing unit, and the like. These functions can also be realized by hardware. Further, the ECU can be integrated into one, and can be further divided. In the present embodiment, when the program is executed by the ECU, the host vehicle position estimation unit 46, the target vehicle speed calculation unit 48, the necessary deceleration calculation unit 50, the acceleration / deceleration calculation unit 52, and the deceleration control unit 54. And function as a reaction force timing learning unit 58 and an accelerator pedal reaction force control unit 60.

  The own vehicle position estimation unit 46 determines the distance from the map information and the vehicle position information acquired by the map information acquisition unit 12 to the curve start position, the own vehicle position during the curve travel, and the remaining curve distance from the midway position of the curve. Etc.

  The target vehicle speed calculation unit 48 recognizes a curve ahead of the vehicle from the map information acquired by the map information acquisition unit 12 and the vehicle position information obtained by the own vehicle position estimation unit 46, and enters the curve start position. A target target vehicle speed VS is calculated. The target vehicle speed VS is calculated based on the curve shape (curvature and the like) and gradient information. Specifically, the upper limit of the lateral G generated in the vehicle during curve driving is determined, and the target vehicle speed VS is calculated so as to be equal to or lower than the lateral G. The target vehicle speed calculation unit 48 always calculates the distance from the vehicle to the curve start position.

  The necessary deceleration calculation unit 50 includes an actual vehicle speed V detected by the vehicle speed detection unit 14, a target vehicle speed VS calculated by the target vehicle speed calculation unit 48, an acceleration / deceleration A calculated by the acceleration / deceleration calculation unit 52, Based on the engine brake correction value, a necessary deceleration X required to bring the vehicle to the target vehicle speed VS at the curve start position is calculated.

  The acceleration / deceleration calculation unit 52 differentiates the actual vehicle speed V detected by the vehicle speed detection unit 14 to calculate the acceleration / deceleration A of the vehicle. Instead of differentiating the vehicle speed V, it is also possible to detect the vehicle acceleration / deceleration A using a device such as a G sensor.

  The deceleration control unit 54 performs automatic brake control so that the required deceleration X calculated by the required deceleration calculation unit 50 is obtained. The deceleration control unit 54 outputs a brake operation signal to the brake device 24 so as to generate the necessary deceleration X.

  The reaction force timing learning unit 58 learns the timing at which the accelerator pedal 40 generates a reaction force based on the timing of the deceleration operation performed by the driver. The deceleration operation here includes an operation in which the driver releases his / her foot from the accelerator pedal 40. The reaction force timing learning unit 58 stores the reaction force generation acceleration / deceleration threshold Th and changes the reaction force generation acceleration / deceleration threshold Th based on the timing of the deceleration operation performed by the driver. The reaction force generation acceleration / deceleration threshold value Th is for measuring the timing at which the accelerator pedal 40 generates a reaction force. The reaction force timing learning unit 58 also changes the reaction force generation acceleration / deceleration threshold Th when the brake pedal 36 or the accelerator pedal 40 is operated while the deceleration control unit 54 is performing the automatic brake control. Let

  The reaction force generation acceleration / deceleration threshold Th before learning is set to a fixed value. For example, an average value (for example, −0.12 G) of deceleration generated by a general driver by braking can be set. When setting the reaction force generation acceleration / deceleration threshold value Th, an upper limit value and a lower limit value are taken into consideration. For example, -0.05G and -0.18G are set as the threshold values.

  The accelerator pedal reaction force control unit 60 causes the accelerator pedal 40 to generate a reaction force when there is a difference between the target vehicle speed VS calculated by the target vehicle speed calculation unit 48 and the actual vehicle speed V measured by the vehicle speed detection unit 14. Further, the timing for generating the reaction force on the accelerator pedal 40 is changed based on the timing learned by the reaction force timing learning unit 58. Here, the reaction force is generated based on the reaction force generation acceleration / deceleration threshold Th stored in the reaction force timing learning unit 58. The accelerator pedal reaction force control unit 60 determines a reaction force generation timing for the accelerator pedal 40 and outputs a reaction force operation signal to the accelerator pedal reaction force applying unit 26.

  The brake device 24 includes a device that brakes the vehicle. For example, the hydraulic pressure of the brake fluid is changed so that the required deceleration X is obtained according to the brake operation signal output from the deceleration control unit 54.

  The accelerator pedal reaction force applying unit 26 includes a device that generates a reaction force on the accelerator pedal 40. For example, in response to a reaction force operation signal output from the accelerator pedal reaction force control unit 60, an electric motor or the like is operated to generate a reaction force on the accelerator pedal 40.

[Concept of the present invention]
The concept of the present invention will be described with reference to FIGS. 2A and 2B. FIG. 2A is a characteristic diagram showing the value of the reaction force applied to the accelerator pedal 40 by the accelerator pedal reaction force applying unit 26 over time. The shape of this characteristic Ch is always constant. As shown in FIG. 2A, the reaction force increases linearly from occurrence, reaches a maximum when the elapsed time reaches Tmax, and then decreases linearly. In the present embodiment, the reaction force generation acceleration / deceleration threshold Th set in the reaction force timing learning unit 58 is set so that the driver lifts his / her foot from the accelerator pedal 40 during the period from reaction force generation to Tmax (for example, timing T2). It is something to change.

  FIG. 2B is an explanatory diagram showing the relationship between the traveling road L before the curved road Cu and the necessary deceleration X. Here, it is assumed that a vehicle (not shown) traveling at the vehicle speed V decelerates to the target vehicle speed VS at the curve start position Cus. The deceleration required for the vehicle traveling at the vehicle speed V at the position P1 farthest from the curve start position Cus to the vehicle speed VS at the curve start position Cus (required deceleration X) is X1. The deceleration (necessary deceleration X) necessary for a vehicle traveling at the position P2 at the vehicle speed V to decelerate to the vehicle speed VS at the curve start position Cus is X2 (| X2 |> | X1 |). The deceleration required for the vehicle traveling at the vehicle speed V at the position P3 closest to the curve start position Cus to the vehicle speed VS at the curve start position Cus (required deceleration X) is X3 (| X3 |> | X2 |) It is.

  In a vehicle traveling at a constant vehicle speed, as shown in FIG. 2B, the required deceleration X decreases (| X | increases) as it approaches the curve start position Cus. In the present invention, when the required deceleration X falls below the reaction force generation acceleration / deceleration threshold Th, the accelerator pedal 40 generates a reaction force. That is, as the reaction force generation acceleration / deceleration threshold value Th decreases (as | Th | increases), the reaction force is generated in the accelerator pedal 40 at a position closer to the curve start position Cus. As the reaction force generation acceleration / deceleration threshold value Th increases (the smaller | Th |), the reaction force is generated in the accelerator pedal 40 at a position farther from the curve start position Cus.

  Here, it is assumed that the deceleration X2 is set to the reaction force generation acceleration / deceleration threshold Th. At this time, as shown in FIG. 2A, a reaction force is generated in the accelerator pedal 40 when the necessary deceleration X calculated for the vehicle traveling at the vehicle speed V becomes X2. In FIG. 2A, when the timing when the driver releases his / her foot from the accelerator pedal 40 is T2 between the reaction force generation timing and Tmax, the reaction force generation timing is just right. On the other hand, when the timing at which the driver removes his / her foot from the accelerator pedal 40 is T1 before the reaction force generation timing, the reaction force generation timing is late. For this reason, the reaction force generation acceleration / deceleration threshold value Th is increased (| Th | is decreased). That is, the reaction force generation acceleration / deceleration threshold value Th is changed to the necessary deceleration X1 side. Further, when the timing when the driver releases his / her foot from the accelerator pedal 40 is T3 after Tmax, the reaction force generation timing is early. For this reason, the reaction force generation acceleration / deceleration threshold value Th is lowered (| Th | is increased). That is, the reaction force generation acceleration / deceleration threshold value Th is changed to the necessary deceleration X3 side.

  In this specification, lowering the reaction force generation acceleration / deceleration threshold Th means changing the reaction force generation acceleration / deceleration threshold Th so that a reaction force is generated in the accelerator pedal 40 at a distance close to the curve start position Cus. That means. As shown in FIG. 2B, the closer to the curve start position Cus, the smaller the required deceleration X becomes (| X | becomes larger). Further, increasing the reaction force generation acceleration / deceleration threshold value Th means changing the reaction force generation acceleration / deceleration threshold value Th so that the reaction force is generated in the accelerator pedal 40 at a distance far from the curve start position Cus. . As shown in FIG. 2B, the required deceleration X increases as the distance from the curve start position Cus increases (| X | decreases).

As will be described later, in the present embodiment, the reaction force generation acceleration / deceleration threshold value Th is changed based on the following determination.
When the reaction force is generated in the accelerator pedal 40 and the accelerator pedal 40 is released before the reaction force reaches the maximum value (before the arrival of Tmax), the reaction force generation acceleration / deceleration threshold Th is not changed.
When the reaction force is generated in the accelerator pedal 40 and the accelerator pedal 40 is released after the reaction force reaches the maximum value (after the arrival of Tmax), the reaction force generation acceleration / deceleration threshold value Th is lowered.
When it is time to generate a reaction force on the accelerator pedal 40 and the accelerator pedal 40 is not operated, the reaction force generation acceleration / deceleration threshold Th is increased.
When the automatic brake is activated and the brake pedal 36 is operated, the reaction force generation acceleration / deceleration threshold Th is increased.
When the automatic brake is activated and the accelerator pedal 40 is operated, the reaction force generation acceleration / deceleration threshold value Th is lowered.

[Various processes performed in the vehicle travel control device 10]
Next, various processes performed by the vehicle travel control device 10 will be described with reference to a flowchart.

<Normal learning initialization process>
FIG. 3 is a flowchart for explaining the normal learning initialization process. In step S1, the reaction force timing learning unit 58 sets an initial value (for example, −0.12G) for the reaction force generation acceleration / deceleration threshold value Th. In step S2, the reaction force timing learning unit 58 sets an initial value (eg, 0.01 G) for the reaction force generation acceleration / deceleration threshold change amount Thv. The reaction force generation acceleration / deceleration threshold change amount Thv is a basic change amount used when changing the reaction force generation acceleration / deceleration threshold Th.

<Reaction force generation processing>
FIG. 4 is a flowchart for explaining the reaction force generation process. In step S11, the map information acquisition unit 12, the vehicle speed detection unit 14, the brake pedal operation detection unit 16, and the accelerator pedal operation detection unit 18 update various inputs. In step S12, the target vehicle speed calculation unit 48 sets the target vehicle speed VS for the vehicle to travel safely on the curve based on the curve curvature and gradient information included in the map information acquired by the map information acquisition unit 12. calculate.

  In step S13, the required deceleration calculation unit 50 performs a predetermined calculation process based on the vehicle speed V, the target vehicle speed VS, the acceleration / deceleration A, and the engine brake correction value, and calculates the required deceleration X. Since the engine brake correction value differs for each gear position, it is determined according to the gear position at that time.

  In step S14, it is determined whether or not a reaction force is generated on the accelerator pedal 40. Specifically, the vehicle speed V detected by the vehicle speed detector 14 is larger (faster) than the target vehicle speed VS calculated by the target vehicle speed calculator 48, and the required deceleration calculated by the required deceleration calculator 50. When X is smaller than the reaction force generation acceleration / deceleration threshold Th (| X |> | Th |) and the opening degree of the accelerator pedal 40 detected by the accelerator pedal operation detection unit 18 is equal to or larger than the accelerator on threshold ( Step S14: YES), the process proceeds to Step S15.

  On the other hand, in step S14, the vehicle speed V detected by the vehicle speed detection unit 14 is smaller (slower) than the target vehicle speed VS calculated by the target vehicle speed calculation unit 48, or is calculated by the necessary deceleration calculation unit 50. When the deceleration X is equal to or greater than the reaction force generation acceleration / deceleration threshold Th (| X | ≦ | Th |), or the opening degree of the accelerator pedal 40 detected by the accelerator pedal operation detecting unit 18 is smaller than the accelerator-on threshold. (Step S14: NO), no reaction force is applied to the accelerator pedal 40.

  In step S15, the reaction force of the accelerator pedal 40 is started. The accelerator pedal reaction force control unit 60 outputs a reaction force operation signal to the accelerator pedal reaction force applying unit 26. The accelerator pedal reaction force application unit 26 operates an electric motor or the like according to the reaction force operation signal to generate a reaction force on the accelerator pedal 40. Simultaneously with the generation of the reaction force, the time t is counted.

<Reaction force timing learning process (1)>
Here, the following determination and learning (adjustment of reaction force generation acceleration / deceleration threshold Th) are performed.
When the reaction force is generated in the accelerator pedal 40 and the accelerator pedal 40 is released before the reaction force reaches the maximum value (before the arrival of Tmax), the reaction force generation acceleration / deceleration threshold Th is not changed.
When the reaction force is generated in the accelerator pedal 40 and the accelerator pedal 40 is released after the reaction force reaches the maximum value (after the arrival of Tmax), the reaction force generation acceleration / deceleration threshold value Th is lowered.
When it is time to generate a reaction force on the accelerator pedal 40 and the accelerator pedal 40 is not operated, the reaction force generation acceleration / deceleration threshold Th is increased.

  FIG. 5 is a flowchart for explaining the reaction force timing learning process (1). The reaction force timing learning unit 58 performs the following processing. In step S21, it is determined whether or not a reaction force is being generated. If the reaction force is being generated (step S21: YES), the process proceeds to step S22. If the reaction force is not being generated (step S21: NO), the process proceeds to step S26.

  In step S22, it is determined whether or not the accelerator pedal 40 is operated. When the opening degree of the accelerator pedal 40 is smaller than the accelerator-off threshold (step S22: YES), the driver has released his / her foot from the accelerator pedal 40 due to a reaction force. In this case, the process proceeds to step S23. On the other hand, when the opening degree of the accelerator pedal 40 is greater than or equal to the accelerator-off threshold (step S22: NO), the accelerator pedal 40 is being operated and learning is not performed.

  In step S23, the reaction force timing learning unit 58 calculates a time t from when the reaction force is generated until the driver lifts his / her foot from the accelerator pedal 40. The timing of time t started in step S15 in FIG. 4 ends when the driver removes his / her foot from the accelerator pedal 40. The time t at this time is calculated.

  In step S24, it is determined whether time t is shorter than time Tmax shown in FIG. 2A. When the time t is shorter than the time Tmax (step S24: YES), the set reaction force generation acceleration / deceleration threshold value Th (that is, the reaction force generation acceleration / deceleration threshold value Th used in step S14 of FIG. 4) is appropriate. Therefore, the reaction force timing learning unit 58 maintains the reaction force generation acceleration / deceleration threshold value Th without changing it. That is, no learning is performed.

  On the other hand, when the time t is longer than or equal to the time Tmax (step S24: NO), the driver has lifted his / her foot from the accelerator pedal 40 after the reaction force reaches the maximum value. In this case, the set reaction force generation acceleration / deceleration threshold value Th (that is, the reaction force generation acceleration / deceleration threshold value Th used in step S14 in FIG. 4) is large (small in absolute value). For this reason, the process proceeds to step S25 in order to change the reaction force generation acceleration / deceleration threshold value Th.

  In step S25, the reaction force timing learning unit 58 decreases the reaction force generation acceleration / deceleration threshold value Th. Specifically, the reaction force generation acceleration / deceleration threshold change amount Thv is subtracted from the reaction force generation acceleration / deceleration threshold Th (Th = Th−Thv).

  When the process proceeds from step S21 to step S26, it is determined in step S26 whether the reaction force is generated or whether the accelerator pedal 40 is operated. When it is the reaction force generation timing and the opening degree of the accelerator pedal 40 is smaller than the accelerator-off threshold (step S26: YES), the driver has already lifted his / her foot from the accelerator pedal 40 when the reaction force is generated. In this case, the set reaction force generation acceleration / deceleration threshold value Th (that is, the reaction force generation acceleration / deceleration threshold value Th used in step S14 of FIG. 4) is small (large in absolute value). Therefore, the process proceeds to step S27 in order to change the reaction force generation acceleration / deceleration threshold value Th. On the other hand, when it is not the reaction force generation timing or when the opening degree of the accelerator pedal 40 is greater than or equal to the accelerator-off threshold (step S26: NO), learning is not performed.

  In step S27, the reaction force timing learning unit 58 increases the reaction force generation acceleration / deceleration threshold value Th. Specifically, the reaction force generation acceleration / deceleration threshold change amount Thv is added to the reaction force generation acceleration / deceleration threshold Th (Th = Th + Thv).

<Reaction force timing learning process (2)>
Here, the following determination and learning (adjustment of reaction force generation acceleration / deceleration threshold Th) are performed.
When the automatic brake is activated and the brake pedal 36 is operated, the reaction force generation acceleration / deceleration threshold Th is increased.
When the automatic brake is activated and the accelerator pedal 40 is operated, the reaction force generation acceleration / deceleration threshold value Th is lowered.

  FIG. 6 is a flowchart for explaining the reaction force timing learning process (2). The reaction force timing learning unit 58 performs the following processing. In step S31, when the automatic brake is operating and the brake switch 38 is on (step S31: YES), the driver operates the brake pedal 36 because the deceleration amount is insufficient. State. In this case, the set reaction force generation acceleration / deceleration threshold Th is small (large in absolute value). Therefore, the process proceeds to step S32 in order to change the reaction force generation acceleration / deceleration threshold value Th. On the other hand, if the automatic brake is not operating or the brake switch 38 is not on (step S31: NO), the process proceeds to step S33.

  In step S32, the reaction force timing learning unit 58 increases the reaction force generation acceleration / deceleration threshold value Th. Specifically, the reaction force generation acceleration / deceleration threshold change amount Thv is added to the reaction force generation acceleration / deceleration threshold Th (Th = Th + Thv).

  In step S33, when the automatic brake is operating and the opening degree of the accelerator pedal 40 is greater than or equal to the accelerator-on threshold (step S33: YES), the driver depresses the accelerator pedal because the deceleration amount is excessive. 40 is operating. In this case, the set reaction force generation acceleration / deceleration threshold Th is large (small in absolute value). Therefore, the process proceeds to step S34 in order to change the reaction force generation acceleration / deceleration threshold value Th. On the other hand, when the automatic brake is not operating or the opening degree of the accelerator pedal 40 is smaller than the accelerator-on threshold value (step S33: NO), the reaction force generation acceleration / deceleration threshold value Th is not changed.

  In step S34, the reaction force timing learning unit 58 decreases the reaction force generation acceleration / deceleration threshold value Th. Specifically, the reaction force generation acceleration / deceleration threshold change amount Thv is subtracted from the reaction force generation acceleration / deceleration threshold Th (Th = Th−Thv).

<External environment learning initialization processing>
When a vehicle travels in a bad external environment such as bad weather (rain, fog, etc.), the driver's brake operation tends to be earlier than usual. Therefore, in this embodiment, when the driver performs a predetermined operation pattern, it is estimated that the vehicle is traveling in bad weather, and the processes shown in FIGS. 7 and 8 are performed.

  FIG. 7 is a flowchart for explaining the external environment learning initialization process. In step S41, the reaction force timing learning unit 58 sets the value of the reaction force generation acceleration / deceleration threshold Th in use as the reaction force generation acceleration / deceleration threshold Thr for external environment learning. In step S42, the reaction force timing learning unit 58 sets the environment learning counter C to 0.

<Reaction force timing learning process (external environment)>
Here, the following judgment and learning (adjustment of reaction force generation acceleration / deceleration threshold Thr) are performed.
The timing when the reaction force is generated on the accelerator pedal 40. If the accelerator pedal 40 is not operated, the automatic brake is activated, the brake pedal 36 is operated, and the vehicle is significantly below the target vehicle speed VS, the reaction force The generated acceleration / deceleration threshold value Thr is significantly increased.

  FIG. 8 is a flowchart for explaining the reaction force timing learning process (external environment). The reaction force timing learning unit 58 performs the following processing. In step S51, it is determined whether the reaction force is generated or whether the accelerator pedal 40 is operated. When it is the reaction force generation timing and the opening degree of the accelerator pedal 40 is smaller than the accelerator-off threshold (step S51: YES), the process proceeds to step S52. On the other hand, when it is not the reaction force generation timing or when the opening degree of the accelerator pedal 40 is greater than or equal to the accelerator-off threshold (step S51: NO), the process proceeds to step S55.

  In step S52, when the automatic brake is operating and the brake switch 38 is on (step S52: YES), the process proceeds to step S53. On the other hand, if the automatic brake is not operating or the brake switch 38 is not on (step S52: NO), the process proceeds to step S55.

  In step S53, it is determined whether or not the vehicle speed Vin when entering the curve is smaller than a value obtained by subtracting the environmental learning vehicle speed from the target vehicle speed VS. The environmental learning vehicle speed is a set value used for detecting that the vehicle is decelerating significantly when entering a curve by a driver's brake operation, and a predetermined vehicle speed is set. In this embodiment, about 10 km / h is set. When the vehicle speed Vin at the time of entering the curve is smaller than the target vehicle speed VS-environmental learning vehicle speed (step S53: YES), the vehicle speed Vin is significantly reduced than the target vehicle speed VS. In this case, the process proceeds to step S54. On the other hand, when the vehicle speed Vin when entering the curve is greater than or equal to the target vehicle speed VS-environment learning vehicle speed (step S53: NO), the process proceeds to step S55.

  In step S54, the reaction force timing learning unit 58 updates the environment learning counter C by adding 1 (C = C + 1).

  In step S55, it is determined whether or not the environmental learning counter C is larger than the environmental learning counter threshold value. An arbitrary numerical value of 2 or more is set in advance as the environmental learning counter threshold value. When the environmental learning counter C is larger than the environmental learning counter threshold (step S55: YES), it is the timing for generating a reaction force on the accelerator pedal 40, the accelerator pedal 40 is not operated, the automatic brake is activated, and the brake pedal 36 Is operated and the state where the vehicle is significantly lower than the target vehicle speed VS occurs more than the environmental learning counter threshold value. Such a state is presumed to deteriorate the external environment. In this case, the process proceeds to step S56. On the other hand, when the environmental learning counter C is smaller than or equal to the environmental learning counter threshold (step S55: NO), learning is not performed.

  In step S56, the reaction force timing learning unit 58 significantly increases the reaction force generation acceleration / deceleration threshold value Thr for external environment learning. Specifically, a reaction force generation acceleration / deceleration threshold change amount Thv that is α times the reaction force generation acceleration / deceleration threshold Thr is added (Thr = Thr + α × Thv). α is about 2-3.

  Similar to the reaction force generation acceleration / deceleration threshold Th, the upper limit value and the lower limit value are considered when setting the reaction force generation acceleration / deceleration threshold Thr for external environment learning. For example, -0.00G and -0.18G are set as each threshold value.

  The above is the various processes performed by the vehicle travel control device 10. In the present embodiment, the reaction force timing learning unit 58 maintains the reaction force generation acceleration / deceleration threshold value Thr for external environment learning until the drive source switch 20 shown in FIG. 1 is turned off. Further, the reaction force timing learning unit 58 stores the reaction force generation acceleration / deceleration threshold value Th when using the reaction force generation acceleration / deceleration threshold value Thr for external environment learning. When the drive source switch 20 is turned on again after being turned off, the stored reaction force generation acceleration / deceleration threshold Th is restored.

[Summary of Embodiment]
The vehicle travel control apparatus 10 according to the present embodiment targets a curve detection unit (map information acquisition unit 12) that detects a curve road Cu in front of the vehicle and the vehicle travels on a road including the curve road Cu. A target vehicle speed calculation unit 48 that calculates the target vehicle speed VS and an accelerator pedal reaction force control unit 60 that generates a reaction force on the accelerator pedal 40 when there is a difference between the target vehicle speed VS and the actual vehicle speed V are provided. Moreover, the reaction force timing learning part 58 which learns the timing which generates the reaction force to the accelerator pedal 40 based on the timing of the deceleration operation which a driver | operator performs is provided. The accelerator pedal reaction force control unit 60 changes the timing at which the accelerator pedal 40 generates a reaction force based on the timing learned by the reaction force timing learning unit 58.

  In the present embodiment, the timing at which the accelerator pedal 40 generates a reaction force is learned based on the timing of the deceleration operation performed by the driver before entering the curved road Cu. Then, based on the learned timing, the timing at which the accelerator pedal 40 generates a reaction force is changed. Thus, according to this embodiment, in order to learn the deceleration operation performed by the driver before entering the curved road Cu, the subsequent reaction force control before entering the curved road Cu is appropriately performed according to the preference of the driver. be able to.

  In addition, the present embodiment includes a necessary deceleration calculation unit 50 that calculates a necessary deceleration X necessary for changing from the actual vehicle speed V to the target vehicle speed VS. The accelerator pedal reaction force control unit 60 causes the accelerator pedal 40 to generate a reaction force when the required deceleration X calculated by the required deceleration calculation unit 50 falls below the reaction force generation acceleration / deceleration threshold Th. The reaction force timing learning unit 58 changes the reaction force generation acceleration / deceleration threshold Th based on the timing of the deceleration operation performed by the driver. According to the present embodiment, the timing of the reaction force generated by the accelerator pedal 40 can be performed by changing the reaction force generation acceleration / deceleration threshold Th.

  In addition, the present embodiment further includes an accelerator pedal operation detection unit 18 that detects an operation of the accelerator pedal 40. Then, when the operation of the accelerator pedal 40 is not detected by the accelerator pedal operation detection unit 18, the reaction force timing learning unit 58 does not learn the timing for causing the accelerator pedal 40 to generate a reaction force. According to the present embodiment, learning accuracy is improved by not learning when the driver is not operating the accelerator pedal 40.

  In the present embodiment, when a predetermined deceleration operation is performed at least twice, the reaction force generation acceleration / deceleration threshold value Th is set to another reaction force generation acceleration / deceleration threshold value Thr that is larger than the reaction force generation acceleration / deceleration threshold value Thr. change. In a driving environment such as rainy weather or fog, the driver tends to decelerate early. In such a case, since the driver releases the accelerator pedal 40 early, it is preferable that the timing of the reaction force generated in the accelerator pedal 40 is advanced. According to this embodiment, the reaction force generation acceleration / deceleration threshold value Thr is changed according to the driver's operation. For this reason, the generation timing of the reaction force generated in the accelerator pedal 40 can be advanced.

  In the present embodiment, the reaction force timing learning unit 58 maintains the reaction force generation acceleration / deceleration threshold value Thr until the vehicle drive source is turned off. Environments such as rain and fog often continue during a single run (vehicle drive source on to off). Therefore, when the reaction force generation acceleration / deceleration threshold value Thr larger than the normal reaction force generation acceleration / deceleration threshold value Thr is changed, the changed reaction force is changed during one run (vehicle drive source ON to OFF). It is desirable to maintain the force generation acceleration / deceleration threshold value Thr. According to the present embodiment, another reaction force generation acceleration / deceleration threshold value Thr is maintained until the vehicle drive source is turned off, and therefore the timing of the reaction force generated by the accelerator pedal 40 can be made appropriate.

  The reaction force timing learning unit 58 stores the reaction force generation acceleration / deceleration threshold value Th before changing to another reaction force generation acceleration / deceleration threshold value Thr, and is turned on after the vehicle drive source is turned off. The reaction force generation acceleration / deceleration threshold value Th is returned to. Environments such as rain and fog are unlikely to last for a long period of time, so if you change to another reaction force generation acceleration / deceleration threshold Thr that is larger than the normal reaction force generation acceleration / deceleration threshold Thr, It is desirable to return to the reaction force generation acceleration / deceleration threshold Th. According to the present embodiment, the normal reaction force generation acceleration / deceleration threshold Th is returned to the normal reaction force generation threshold Th when the drive source is turned on next time, so that the timing of the reaction force generated by the accelerator pedal 40 can be made appropriate.

  In this embodiment, a curve road Cu ahead of the vehicle is detected, a target vehicle speed VS that is a target when the vehicle travels on a road including the curve road Cu is calculated (step S12), and the target vehicle speed VS and the actual vehicle speed V are calculated. When there is a divergence (step S14: YES), a reaction force is generated on the accelerator pedal 40 (step S15). The timing for generating the reaction force on the accelerator pedal 40 is learned based on the timing of the deceleration operation performed by the driver (steps S25, S27, S32, S34, S56), and the reaction force is applied to the accelerator pedal 40 based on the learned timing. Is generated (step S15).

  In the present embodiment, the necessary deceleration X necessary to obtain the target vehicle speed VS from the actual vehicle speed V is calculated, and the reaction force is applied to the accelerator pedal 40 at a timing when the necessary deceleration X falls below the reaction force generation acceleration / deceleration threshold Th. And the reaction force generation acceleration / deceleration threshold value Th is changed based on the timing of the deceleration operation performed by the driver. Then, when the reaction force is generated in the accelerator pedal 40 and the accelerator pedal 40 is released before the reaction force reaches the maximum value (step S24: YES), the reaction force generation acceleration / deceleration threshold value Th is not changed. If the accelerator pedal 40 is released after the reaction force is generated in the accelerator pedal 40 and the reaction force reaches the maximum value (step S24: NO), the reaction force generation acceleration / deceleration threshold value Th is lowered (step S25). . Further, when it is time to generate a reaction force on the accelerator pedal 40 and the accelerator pedal 40 is not operated (step S26: YES), the reaction force generation acceleration / deceleration threshold value Th is increased (step S27). When the automatic brake is operated and the brake pedal 36 is operated (step S31: YES), the reaction force generation acceleration / deceleration threshold value Th is increased (step S32). When the automatic brake is operated and the accelerator pedal 40 is operated (step S33: YES), the reaction force generation acceleration / deceleration threshold value Th is lowered (step S34).

  It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Vehicle travel control apparatus 12 ... Map information acquisition part 14 ... Vehicle speed detection part 16 ... Brake pedal operation detection part 18 ... Accelerator pedal operation detection part 20 ... Drive source switch 22 ... Travel control part 24 ... Brake apparatus 26 ... Accelerator pedal Reaction force application unit 48 ... target vehicle speed calculation unit 50 ... required deceleration calculation unit 52 ... acceleration / deceleration calculation unit 54 ... deceleration control unit 58 ... reaction force timing learning unit 60 ... accelerator pedal reaction force control unit

Claims (6)

A curve detector for detecting a curved road ahead of the vehicle;
A target vehicle speed calculation unit that calculates a target vehicle speed that is a target when the vehicle travels on a road including the curved road;
In a vehicle travel control device comprising: an accelerator pedal reaction force control unit that generates a reaction force on an accelerator pedal when there is a difference between the target vehicle speed and the actual vehicle speed;
A reaction force timing learning unit that learns the timing of generating the reaction force on the accelerator pedal based on the timing of the deceleration operation performed by the driver ;
An accelerator pedal operation detector for detecting the operation of the accelerator pedal ;
The accelerator pedal reaction force control unit changes the timing at which the accelerator pedal generates the reaction force based on the timing learned by the reaction force timing learning unit ,
The accelerator pedal reaction force control unit performs a first control for increasing the reaction force and a second control for decreasing the reaction force after the first control when generating the reaction force,
When the accelerator pedal operation detection unit detects that the accelerator pedal is released during the first control, the reaction force timing learning unit does not learn the timing for generating the reaction force in the accelerator pedal,
When the accelerator pedal operation detection unit detects that the accelerator pedal is released during the second control, the reaction force timing learning unit learns the timing for generating the reaction force in the accelerator pedal. A vehicle travel control device. The vehicle travel control apparatus according to claim 1,
A further required deceleration calculation unit for calculating a required deceleration required to obtain the target vehicle speed from the actual vehicle speed;
The accelerator pedal reaction force control unit causes the accelerator pedal to generate the reaction force at a timing when the required deceleration calculated by the required deceleration calculation unit falls below a reaction force generation acceleration / deceleration threshold.
The said reaction force timing learning part changes the said reaction force generation | occurrence | production acceleration / deceleration threshold value based on the timing of the deceleration operation which a driver | operator performs. The vehicle travel control apparatus characterized by the above-mentioned. A curve detector for detecting a curved road ahead of the vehicle;
A target vehicle speed calculation unit that calculates a target vehicle speed that is a target when the vehicle travels on a road including the curved road;
In a vehicle travel control device comprising: an accelerator pedal reaction force control unit that generates a reaction force on an accelerator pedal when there is a difference between the target vehicle speed and the actual vehicle speed;
A reaction force timing learning unit that learns the timing of generating the reaction force on the accelerator pedal based on the timing of the deceleration operation performed by the driver;
A required deceleration calculating unit that calculates a required deceleration required to obtain the target vehicle speed from the actual vehicle speed;
Additionally and a deceleration control unit that performs automatic braking control such necessary deceleration calculated by the required deceleration calculation unit is obtained,
The accelerator pedal reaction force control unit is
The timing for generating the reaction force on the accelerator pedal is changed based on the timing learned by the reaction force timing learning unit,
At the timing when the required deceleration calculated by the required deceleration calculation unit falls below a reaction force generation acceleration / deceleration threshold, the accelerator pedal generates the reaction force,
The reaction force timing learning unit
Based on the timing of the deceleration operation performed by the driver, the reaction force generation acceleration / deceleration threshold value is changed,
If the automatic brake is operating, the brake switch is on, and the vehicle speed at the time of entering the curve is smaller than the value obtained by subtracting the predetermined set value from the target vehicle speed , the reaction will occur. A vehicle travel control device, wherein the force generation acceleration / deceleration threshold value is changed to another reaction force generation acceleration / deceleration threshold value whose absolute value is smaller than the reaction force generation acceleration / deceleration threshold value. In the vehicle travel control device according to claim 3 ,
The said reaction force timing learning part maintains the said another reaction force generation | occurrence | production acceleration / deceleration threshold value until the drive source of a vehicle is turned off. The vehicle travel control apparatus characterized by the above-mentioned. In the vehicle travel control device according to claim 4 ,
The reaction force timing learning unit stores the reaction force generation acceleration / deceleration threshold before changing to the another reaction force generation acceleration / deceleration threshold, and is turned on after the vehicle drive source is turned off. And returning to the reaction force generation acceleration / deceleration threshold value. Detects a curved road ahead of the vehicle,
Calculating a target vehicle speed which is a target when the vehicle travels on a road including the curved road,
In the vehicle travel control method for generating a reaction force on the accelerator pedal when there is a difference between the target vehicle speed and the actual vehicle speed,
Learning the timing of generating the reaction force on the accelerator pedal based on the timing of the deceleration operation performed by the driver,
Generate the reaction force on the accelerator pedal based on the learned timing ,
The vehicle includes a necessary deceleration calculation unit that calculates a necessary deceleration necessary to obtain the target vehicle speed from an actual vehicle speed,
At the timing when the required deceleration falls below the reaction force generation acceleration / deceleration threshold, the reaction force is generated on the accelerator pedal,
Based on the timing of the deceleration operation performed by the driver, the reaction force generation acceleration / deceleration threshold value is changed,
When the accelerator pedal is released before the reaction force is generated and the reaction force reaches the maximum value, the reaction force generation acceleration / deceleration threshold value is not changed.
When the accelerator pedal is released after the reaction force is generated in the accelerator pedal and the reaction force reaches the maximum value, the reaction force generation acceleration / deceleration threshold is lowered,
When it is the timing to generate the reaction force on the accelerator pedal and the accelerator pedal is not operated, the reaction force generation acceleration / deceleration threshold is raised,
The vehicle performs automatic brake control so that the required deceleration calculated by the required deceleration calculation unit is obtained,
When the automatic brake is operated and the brake pedal is operated, the reaction force generation acceleration / deceleration threshold value is raised,
A vehicular travel control method characterized by lowering the reaction force generation acceleration / deceleration threshold when an automatic brake is operated and an accelerator pedal is operated .

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