JP2015098224A - Braking-driving force control apparatus and braking-driving force control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a braking-driving force control apparatus and a braking-driving force control method, which enable a driver to facilitate an operation for deceleration actively, the driver who has predicted the occurrence of an unstable behavior of a vehicle due to an increase in deceleration in the state of the grip performance of a wheel being undermined.SOLUTION: An apparatus or method performs: detecting an operation amount of a braking-driving force operator; decreasing a braking-force instruction value from a pre-set initial braking-force instruction value in response to an increase in a detected operation amount in a braking zone where the detected operation value is between an un-operated state and less than a given operation amount, or setting a driving-force instruction value in accordance with a difference between the given operation amount and the detected operation amount in a driving zone where the detected operation amount is equal to or more than the given operation amount; detecting a wheel grip value that is a value in accordance with grip performance of the wheel; and correcting, if the detected wheel grip value is less than a pre-set wheel grip threshold, the initial braking-force instruction value to be smaller in the braking zone as a difference between the wheel grip value and the wheel grip threshold increases.

Description

  The present invention relates to a braking / driving force control apparatus and a braking / driving force control method for controlling a braking force and a driving force of a vehicle by an operation on one braking / driving force operator.

Conventionally, by controlling the braking force and driving force of a vehicle by an operation (accelerator operation) on one braking / driving force operator by a driver, the longitudinal acceleration (acceleration and deceleration) generated in the vehicle is controlled. As a technique, for example, there is a technique described in Patent Document 1.
In the technique described in Patent Document 1, the target acceleration / deceleration is set according to the opening degree of the braking / driving force operator (pedal) changed by the operation of the driver. Furthermore, the longitudinal acceleration generated in the vehicle is controlled by controlling the opening of the throttle valve based on the set target acceleration / deceleration.

JP 2000-205015 A

However, in the technique described in Patent Document 1, in a state where the grip performance of the wheel is lowered, such as a state where acceleration in the lateral direction is increased during turning, the driver may become unstable due to an increase in deceleration. May occur. For this reason, there exists a possibility that the driver | operator may become difficult to perform deceleration operation actively.
The present invention has been made paying attention to the above-described problems, and makes it easier for a driver who has predicted that unstable behavior occurs due to an increase in deceleration to actively perform the deceleration operation. It is an object of the present invention to provide a braking / driving force control device and a braking / driving force control method.

In order to solve the above problems, the present invention detects a wheel grip value that is a value corresponding to the grip performance of the wheel. Further, when the detected wheel grip value is less than the preset wheel grip threshold, the initial braking force command value preset in the braking range less than the predetermined operation amount is decreased as the deviation between the wheel grip value and the wheel grip threshold is larger. to correct.
Here, the predetermined operation amount is a driving force command corresponding to a deviation between the predetermined operation amount and the detected operation amount of the braking / driving force operator in a driving range where the operation amount of the braking / driving force operator is equal to or greater than the predetermined operation amount. This is a threshold for setting a value, and is set in advance. In addition, the predetermined operation amount is a braking force command value corresponding to an increase in the operation amount of the braking / driving force operator in the braking range where the operation amount of the braking / driving force operator is less than the predetermined operation amount from the unoperated state. Is a threshold value for decreasing from a preset initial braking force command value. The initial braking force command value is a value corresponding to a braking force command value that is a command value of the braking force generated in the vehicle when the operation amount of the braking / driving force operator is not operated.

According to the present invention, the greater the deviation between the wheel grip value and the wheel grip threshold, the more the operation amount of the braking / driving force operator in the braking range in which the operation amount of the braking / driving force operator generates the braking force. It is possible to reduce the degree of change in the deceleration with respect to.
As a result, the amount of increase in deceleration with respect to the operation amount of the braking / driving force operator is reduced, and the driver who is predicted to cause unstable behavior due to the increase in deceleration actively performs the deceleration operation. It becomes possible to make it easier.

1 is a block diagram illustrating a schematic configuration of a vehicle including a braking / driving force control device according to a first embodiment of the present invention. It is a block diagram which shows the structure of a braking / driving force controller. It is a block diagram which shows the structure of a deceleration characteristic calculation part. It is a map which shows the relationship between the absolute value of side G, and the maximum deceleration first correction coefficient. It is a map which shows the relationship between (mu) gradient and the maximum deceleration 2nd correction coefficient. It is a flowchart which shows the process in which a target deceleration calculation part calculates a target deceleration. It is a flowchart which shows a deceleration characteristic reflection process. A map that sets the relationship between the opening of the acceleration / deceleration pedal, the braking force and driving force generated by the vehicle, and the driving margin when the driver has performed an operation to increase the opening of the acceleration / deceleration pedal. is there. It is a figure which shows the relationship between the opening degree of an acceleration / deceleration pedal, and the deceleration generated in a vehicle in the range where the opening degree of an acceleration / deceleration pedal is less than a neutral point. A map that sets the relationship between the opening of the acceleration / deceleration pedal, the braking force and driving force generated by the vehicle, and the driving margin when the driver performs an operation to decrease the opening of the acceleration / deceleration pedal. is there. It is a figure which shows the relationship between the opening degree of an acceleration / deceleration pedal, and the deceleration generated in a vehicle in the range where the opening degree of an acceleration / deceleration pedal is less than a neutral point. A map that sets the relationship between the degree of opening of the acceleration / deceleration pedal, the braking force and driving force generated by the vehicle, and the driving margin when the driver performs an operation to maintain the degree of opening of the acceleration / deceleration pedal. is there. It is a figure which shows the relationship between the opening degree of an acceleration / deceleration pedal, and the deceleration generated in a vehicle in the range where the opening degree of an acceleration / deceleration pedal is less than a neutral point. A map that sets the relationship between the opening of the acceleration / deceleration pedal and brake pedal, the braking force and driving force generated by the vehicle, and the driving margin when the driver depresses the braking pedal. is there. It is a flowchart of the operation | movement performed using the braking / driving force control apparatus of 1st embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
Hereinafter, a first embodiment of the present invention (hereinafter referred to as the present embodiment) will be described with reference to the drawings.
(Constitution)
FIG. 1 is a block diagram illustrating a schematic configuration of a vehicle V including the braking / driving force control device 1 of the present embodiment.
As shown in FIG. 1, a vehicle V including a braking / driving force control device 1 includes an accelerator operation amount sensor 2, a brake operation amount sensor 4, a G sensor 6, a wheel speed sensor 8, and a μ gradient calculation unit 10. And a braking / driving force controller 12 and a brake actuator 14. In addition, the vehicle V including the braking / driving force control device 1 includes a wheel cylinder 16, a power control unit 18, a power unit 20, and wheels W (right front wheel WFR, left front wheel WFL, right rear wheel WRR, left rear Wheel WRL).

  The accelerator operation amount sensor 2 is a sensor that detects, for example, a depression operation amount of the acceleration / deceleration pedal 22 (accelerator pedal) by the driver, which is formed using a pedal stroke sensor. In addition, the accelerator operation amount sensor 2 generates an information signal (which may be referred to as an “accelerator operation amount signal” in the following description) including an operation amount of the acceleration / deceleration pedal 22 by the driver. Output to. The acceleration / deceleration pedal 22 is a pedal that the driver of the vehicle V steps on in response to a braking force request or a driving force request.

Note that the configuration of the accelerator operation amount sensor 2 is not limited to the configuration formed by using the pedal stroke sensor, and for example, the opening degree of the acceleration / deceleration pedal 22 by the driver's stepping operation may be detected.
That is, the accelerator operation amount sensor 2 is a sensor that detects the operation amount of the acceleration / deceleration pedal 22 by the driver.

  The brake operation amount sensor 4 is, for example, a sensor that is formed using a pedal stroke sensor and detects a depression operation amount of the brake pedal 24 (brake pedal) by the driver. In addition, the brake operation amount sensor 4 outputs an information signal (which may be referred to as a “brake operation amount signal” in the following description) including an operation amount of the brake pedal 24 by the driver. Output to. The braking pedal 24 is a pedal that the driver of the vehicle V steps on only in response to a braking force request.

Note that the configuration of the brake operation amount sensor 4 is not limited to the configuration formed using the pedal stroke sensor, like the accelerator operation amount sensor 2, and for example, the opening degree of the brake pedal 24 by the driver's stepping operation It is good also as a structure which detects.
That is, the brake operation amount sensor 4 is a sensor that detects the operation amount of the brake pedal 24 by the driver.

The G sensor 6 includes a block having a function of a lateral acceleration sensor and a block having a function of a longitudinal acceleration sensor.
The block having the function of the lateral acceleration sensor detects acceleration in the lateral direction (vehicle width direction) of the vehicle body in the vehicle V (may be described as “actual lateral acceleration” in the following description). Then, an information signal including the actually measured lateral acceleration detected (in the following description, may be described as “actually measured lateral acceleration signal”) is output to the braking / driving force controller 12.

The block having the function of the longitudinal acceleration sensor detects acceleration in the longitudinal direction of the vehicle body (vehicle longitudinal direction) with respect to the vehicle V. Then, an information signal including the detected acceleration (in the following description, it may be described as “longitudinal acceleration signal”) is output to the μ gradient calculation unit 10 and the braking / driving force controller 12.
The wheel speed sensor 8 detects the rotation speed of the wheel W and outputs an information signal including the detected rotation speed (may be described as “wheel speed signal” in the following description) to the μ gradient calculation unit 10. To do.

  In FIG. 1, the wheel speed sensor 8 that detects the rotational speed of the right front wheel WFR is indicated as a wheel speed sensor 8FR, and the wheel speed sensor 8 that detects the rotational speed of the left front wheel WFL is indicated as a wheel speed sensor 8FL. . Similarly, in FIG. 1, the wheel speed sensor 8 that detects the rotation speed of the right rear wheel WRR is indicated as a wheel speed sensor 8RR, and the wheel speed sensor 8 that detects the rotation speed of the left rear wheel WRL is the wheel speed sensor. Shown as 8RL. In the following description, each wheel W and each wheel speed sensor 8 may be indicated as described above.

  The μ gradient calculation unit 10 determines the acceleration in the vehicle longitudinal direction included in the longitudinal acceleration signal received from the G sensor 6 and the rotational speed of each wheel W included in the wheel speed signal received from each wheel speed sensor 8. Based on this, a μ gradient is calculated. Further, the μ gradient calculation unit 10 outputs an information signal including the calculated μ gradient (in the following description, sometimes described as “road surface μ signal”) to the braking / driving force controller 12.

Here, the μ gradient is, for example, the gradient (corning power) at which the slip angle and the lateral force are obtained on the tire characteristic curve established between the slip angle of the wheel W and the lateral force of the wheel W. . That is, the μ gradient is the rate of change (横 Fy / ∂βt) of the lateral force Fy of the wheel W with respect to the change amount of the slip angle βt of the wheel W.
The braking / driving force controller 12 controls the braking force or driving force generated in the vehicle V and is constituted by a microcomputer. Note that the microcomputer includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like.

Further, the braking / driving force controller 12 performs various processes, which will be described later, based on various input information signals, and command signals (braking command signal, drive command signal) for controlling the brake actuator 14 and the power unit 20. Is output. A specific configuration of the braking / driving force controller 12 will be described later.
Here, the braking command signal is an information signal including a braking force command value for controlling the hydraulic pressure of each wheel cylinder 16. The braking force command value is calculated by the braking / driving force controller 12 in response to a braking force request from the driver of the vehicle V.

On the other hand, the drive command signal is an information signal including a drive force command value for controlling the drive force generated by the power unit 20. The driving force command value is calculated by the braking / driving force controller 12 in response to a driving force request by the driver of the vehicle V.
The brake actuator 14 is a hydraulic pressure control device interposed between a master cylinder (not shown) and each wheel cylinder 16. Further, the brake actuator 14 changes the hydraulic pressure of each wheel cylinder 16 according to the braking force command value included in the braking command signal received from the braking / driving force controller 12 and applies the braking force to each wheel W.

The wheel cylinder 16 generates a pressing force for pressing a brake pad (not shown) constituting the disc brake against a disc rotor (not shown) that rotates integrally with each wheel W.
In FIG. 1, the wheel cylinder 16 disposed with respect to the right front wheel WFR is denoted as a wheel cylinder 16FR, and the wheel cylinder 16 disposed with respect to the left front wheel WFL is denoted as a wheel cylinder 16FL. Similarly, in FIG. 1, the wheel cylinder 16 disposed with respect to the right rear wheel WRR is denoted as a wheel cylinder 16RR, and the wheel cylinder 16 disposed with respect to the left rear wheel WRL is denoted as a wheel cylinder 16RL. In the following description, each wheel cylinder 16 may be indicated as described above.

  The power control unit 18 controls the driving force generated by the power unit 20 according to the driving force command value included in the driving command signal received from the braking / driving force controller 12. In this embodiment, as will be described later, the power unit 20 is formed using an engine. For this reason, the power control unit 18 controls values relating to the driving force generated by the engine (for example, driving torque, rotational speed, transmission gear ratio).

Further, the power control unit 18 outputs an information signal including the current torque (engine torque) generated by the power unit 20 (engine) (in the following description, it may be referred to as “current torque signal”), Output to the braking / driving force controller 12.
The power unit 20 is configured to generate a driving force of the vehicle V, and applies a driving force to each wheel W via a drive shaft (not shown) or the like. In the present embodiment, as an example, a case where the power unit 20 is formed using an engine will be described.

(Specific configuration of braking / driving force controller 12)
Next, a specific configuration of the braking / driving force controller 12 will be described with reference to FIG.
FIG. 2 is a block diagram showing the configuration of the braking / driving force controller 12.
As shown in FIG. 2, the braking / driving force controller 12 includes a braking / driving force calculating pedal opening calculating unit 26, a deceleration characteristic calculating unit 28, a target deceleration calculating unit 30, and a driving force calculating unit 32. A braking force calculation unit 34 is provided.

  The braking / driving force calculating pedal opening calculation unit 26 divides the depression operation amount by a preset sampling time based on the depression operation amount included in the accelerator operation amount signal received from the accelerator operation amount sensor 2. Thereby, the braking / driving force calculating pedal opening degree calculation unit 26 calculates the operation speed (pedal operation speed) of the acceleration / deceleration pedal 22. In the present embodiment, a case where the sampling time is set to 0.2 [s] will be described as an example.

Then, the pedal opening calculation unit 26 for calculating the braking / driving force generates an information signal including the calculated pedal operation speed (may be described as a “pedal operation speed signal” in the following description) as a target deceleration calculation unit. Output to 30.
The braking / driving force calculating pedal opening degree calculation unit 26 is an acceleration / deceleration pedal based on a preset neutral point based on the stepping operation amount included in the accelerator operation amount signal received from the accelerator operation amount sensor 2. The stepping operation amount of 22 is calculated. Then, an information signal including the calculated depression operation amount (in the following description, may be described as an “accelerator pedal operation amount signal”) is output to the driving force calculation unit 32 and the target deceleration calculation unit 30.

  Here, the neutral point is a point at which acceleration and deceleration generated in the vehicle V are switched, that is, a command signal output by the braking / driving force controller 12 is switched to a braking command signal or a driving command signal. The neutral point is a parameter corresponding to the opening degree of the acceleration / deceleration pedal 22 (pedal opening degree) according to the depression operation amount included in the accelerator operation amount signal. For example, the opening of the acceleration / deceleration pedal 22 is about 25%. Corresponds to the degree.

  The neutral point is a stepping operation amount included in the stepping operation amount signal, and indicates a predetermined operation amount that is a parameter corresponding to the operation amount of the acceleration / deceleration pedal 22 (braking / driving force operator). The predetermined operation amount is a braking force command value, which will be described later, in accordance with an increase in the operation amount of the acceleration / deceleration pedal 22 in a braking range where the operation amount of the acceleration / deceleration pedal 22 is less than the predetermined operation amount from an unoperated state. This is a threshold value for decreasing from the initial braking force command value. In addition, the predetermined operation amount is set to a driving force command value corresponding to a deviation between the predetermined operation amount and the operation amount of the acceleration / deceleration pedal 22 in a drive range where the operation amount of the acceleration / deceleration pedal 22 is equal to or greater than the predetermined operation amount. It is a threshold for

  The deceleration characteristic calculation unit 28 is based on the acceleration in the vehicle width direction included in the actually measured lateral acceleration signal received from the G sensor 6 and the μ gradient included in the road surface μ signal received from the μ gradient calculation unit 10. Calculate the maximum deceleration setting value. Then, an information signal including the calculated maximum deceleration setting value (in the following description, may be described as “maximum deceleration setting value signal”) is output to the target deceleration calculation unit 30. The detailed configuration of the deceleration characteristic calculation unit 28 and the process in which the deceleration characteristic calculation unit 28 calculates the maximum deceleration set value will be described later.

Here, the maximum deceleration set value is a value corresponding to the deceleration generated in the vehicle V in a state where the opening degree of the acceleration / deceleration pedal 22 is the minimum value (pedal opening degree = 0).
The target deceleration calculation unit 30 receives a pedal operation speed signal and an accelerator pedal operation amount signal from the braking / driving force calculation pedal opening calculation unit 26, and receives a maximum deceleration set value signal from the deceleration characteristic calculation unit 28. Receive. Furthermore, the target deceleration calculation unit 30 receives a brake operation amount signal from the brake operation amount sensor 4. The vehicle V is generated based on the pedal operation speed included in the pedal operation speed signal, the depressing operation amount of the acceleration / deceleration pedal 22 included in the accelerator pedal operation amount signal, and the maximum deceleration setting value included in the maximum deceleration setting value signal. A target deceleration that is a target value of the deceleration according to the braking force to be calculated is calculated.

Further, the target deceleration calculation unit 30 calculates a braking force to be generated in the vehicle V based on the calculated target deceleration and the depression operation amount of the acceleration / deceleration pedal 22 included in the accelerator pedal operation amount signal.
Further, when receiving the brake operation amount signal from the brake operation amount sensor 4, the target deceleration calculation unit 30 has priority over the other processes, and the depression operation amount of the brake pedal 24 included in the brake operation amount signal. Based on the above, the braking force generated in the vehicle V is calculated.

Then, an information signal including the calculated braking force (which may be described as “braking force signal” in the following description) is output to the braking force calculation unit 34. The process in which the target deceleration calculation unit 30 calculates the target deceleration will be described later.
The driving force calculation unit 32 calculates the driving force command value based on the depression operation amount of the acceleration / deceleration pedal 22 included in the accelerator pedal operation amount signal received from the braking / driving force calculation pedal opening calculation unit 26. Specifically, when the pedal opening corresponding to the depression operation amount included in the accelerator operation amount signal is equal to or greater than the neutral point, the driving force generated in the vehicle V is increased as the opening of the acceleration / deceleration pedal 22 increases. Next, a driving force command value is calculated. Then, the driving force calculation unit 32 outputs an information signal including the calculated driving force command value (may be described as “driving force command value signal” in the following description) to the power control unit 18.

  The braking force calculation unit 34 calculates a braking force command value based on the braking force included in the braking force signal received from the target deceleration calculation unit 30. Then, the braking force calculation unit 34 outputs an information signal including the calculated braking force command value (may be described as “braking force command value signal” in the following description) to the brake actuator 14.

(Detailed configuration of deceleration characteristic calculation unit 28)
Next, a detailed configuration of the deceleration characteristic calculation unit 28 will be described with reference to FIGS. 1 and 2 and FIGS. 3 to 5.
FIG. 3 is a block diagram illustrating a configuration of the deceleration characteristic calculation unit 28.
As shown in FIG. 3, the deceleration characteristic calculation unit 28 includes a maximum deceleration first correction coefficient calculation unit 36, a maximum deceleration second correction coefficient calculation unit 38, a selection deceleration constant generation unit 40, A deceleration characteristic setting unit 42 is provided.
The maximum deceleration first correction coefficient calculation unit 36 calculates the maximum deceleration first correction coefficient based on the acceleration in the vehicle width direction included in the actually measured lateral acceleration signal received from the G sensor 6. Then, an information signal including the calculated maximum deceleration first correction coefficient (in the following description, may be described as “first correction coefficient signal”) is output to the deceleration constant generator for selection 40.

  Here, when the maximum deceleration first correction coefficient calculation unit 36 calculates the maximum deceleration first correction coefficient, for example, the acceleration in the vehicle width direction included in the actually measured lateral acceleration signal in the map shown in FIG. The absolute value (absolute value of horizontal G) is input. FIG. 4 is a map showing the relationship between the absolute value of the lateral G and the maximum deceleration first correction coefficient. In FIG. 4, the vertical axis represents the maximum deceleration first correction coefficient (denoted as “first correction coefficient” in the figure), and the horizontal axis represents the absolute value of the horizontal G.

As shown in FIG. 4, when the absolute value of the acceleration in the vehicle width direction is equal to or smaller than a preset lateral G threshold, the maximum deceleration first correction coefficient is maintained at the initial value “1.0”. To do. The absolute value of acceleration in the vehicle width direction is, for example, positive acceleration in the vehicle width direction and positive acceleration in the vehicle width direction as negative acceleration.
Here, the lateral G threshold value is set according to the structure of the vehicle V (vehicle weight, braking ability, etc.), for example. Further, the lateral G threshold value may be changed according to the vehicle speed, for example.

In the range where the absolute value of acceleration in the vehicle width direction increases and exceeds the lateral G threshold value, the maximum deceleration first correction coefficient is set to the initial value according to the degree of increase in the absolute value of acceleration in the vehicle width direction. Decrease from value (1.0).
The maximum deceleration second correction coefficient calculation unit 38 calculates the maximum deceleration second correction coefficient based on the μ gradient included in the road surface μ signal received from the μ gradient calculation unit 10. Then, an information signal including the calculated maximum deceleration second correction coefficient (in the following description, may be described as “second correction coefficient signal”) is output to the selection deceleration constant generation unit 40.

  Here, when the maximum deceleration second correction coefficient calculation unit 38 calculates the maximum deceleration second correction coefficient, for example, the μ gradient included in the road surface μ signal is input to the map shown in FIG. FIG. 5 is a map showing the relationship between the μ gradient and the maximum deceleration second correction coefficient. In FIG. 5, the vertical axis represents the maximum deceleration second correction coefficient (denoted as “second correction coefficient” in the figure), and the horizontal axis represents μ gradient.

As shown in FIG. 5, the maximum deceleration second correction coefficient is maintained at the initial value “1.0” in the range where the μ gradient is equal to or larger than a predetermined μ gradient threshold.
Here, the μ gradient threshold value is set according to, for example, the structure of the vehicle V (vehicle weight, driving capability, etc.). Further, the μ gradient threshold value may be changed according to the vehicle speed, for example.
Then, in the range where the μ gradient decreases and becomes less than the μ gradient threshold, the maximum deceleration second correction coefficient is decreased from the initial value (1.0) according to the decrease degree of the μ gradient.

  The selection deceleration constant generator 40 receives the first correction coefficient signal from the maximum deceleration first correction coefficient calculator 36 and receives the second correction coefficient signal from the maximum deceleration second correction coefficient calculator 38. receive. The maximum deceleration first correction coefficient included in the first correction coefficient signal, the maximum deceleration second correction coefficient included in the second correction coefficient signal, and the maximum deceleration constant which is a preset constant are selected and selected. Generate a deceleration constant. Further, an information signal including the generated selection deceleration constant (in the following description, may be described as “selection deceleration constant signal”) is output to the deceleration characteristic setting unit 42.

  Here, the maximum deceleration constant is the minimum value of the acceleration / deceleration pedal 22 (pedal opening = 0) in a state where the control according to the situation at the time of traveling such as the state of shipping the vehicle V is not performed. Is a value (for example, 0.3 [G]) corresponding to the braking force generated in the vehicle V. That is, the maximum deceleration constant is a basic characteristic (base characteristic) of the braking force generated in the vehicle V when the opening degree of the acceleration / deceleration pedal 22 is the minimum value. Further, the maximum deceleration constant is set according to specifications such as the braking capability of the vehicle V and the vehicle weight, for example.

  The deceleration characteristic setting unit 42 receives a selection deceleration constant signal from the selection deceleration constant generation unit 40. Then, the selection deceleration constant included in the selection deceleration constant signal is compared with a preset minimum deceleration constant, and a large constant is set as the maximum deceleration set value. Further, a maximum deceleration set value signal including the set maximum deceleration set value is output to the target deceleration calculation unit 30.

  Here, the minimum deceleration constant is, for example, a state where the opening of the acceleration / deceleration pedal 22 is controlled in accordance with acceleration in the vehicle width direction and μ gradient generated in the vehicle V when the vehicle V is traveling. This is a value corresponding to the braking force generated in the vehicle V when the minimum value (pedal opening = 0). That is, the minimum deceleration constant is a characteristic after control of the braking force generated in the vehicle V when the opening degree of the acceleration / deceleration pedal 22 is the minimum value. Further, the minimum deceleration constant is set according to specifications such as the braking ability of the vehicle V and the vehicle weight, and corresponds to a deceleration smaller than the maximum deceleration constant.

(Process in which the target deceleration calculation unit 30 calculates the target deceleration)
Next, the process in which the target deceleration calculation unit 30 calculates the target deceleration will be described with reference to FIGS. 1 to 5 and FIGS. 6 to 14.
FIG. 6 is a flowchart illustrating a process in which the target deceleration calculation unit 30 calculates the target deceleration.

  As shown in FIG. 6, when the target deceleration calculation unit 30 starts processing (START), first, in step S100, it is determined whether or not the opening degree of the acceleration / deceleration pedal 22 is “0” ( “Accelerator opening = 0” shown in the figure). In addition to this, in step S100, a process of determining whether or not an operation (brake operation) for reducing the opening degree of the acceleration / deceleration pedal 22 that the driver (Dr) has depressed has been performed ("Dr" shown in the figure). Brake operation is performed ”).

  Here, whether or not the opening degree of the acceleration / deceleration pedal 22 is “0” is determined based on, for example, the depression operation amount of the acceleration / deceleration pedal 22 included in the accelerator pedal operation amount signal. The determination as to whether or not a brake operation is being performed by the driver is made based on, for example, the pedal operation speed included in the pedal operation speed signal and the depression operation amount of the acceleration / deceleration pedal 22 included in the accelerator pedal operation amount signal. .

If it is determined in step S100 that at least one of the two determinations is not satisfied ("No" shown in the drawing), the processing performed by the target deceleration calculation unit 30 proceeds to step S102.
On the other hand, when it is determined in step S100 that the opening degree of the acceleration / deceleration pedal 22 is “0” and the driver is performing a brake operation (“Yes” shown in the figure), the target deceleration calculation unit 30 The process performed by the process proceeds to step S104.

In step S102, a process of determining whether or not the opening degree of the acceleration / deceleration pedal 22 is equal to or greater than the neutral point ("accelerator opening degree ≥ neutral point" shown in the figure) is performed.
Here, whether or not the opening degree of the acceleration / deceleration pedal 22 is equal to or greater than the neutral point is determined based on, for example, the depression operation amount of the acceleration / deceleration pedal 22 included in the accelerator pedal operation amount signal.
When it is determined in step S100 that the opening degree of the acceleration / deceleration pedal 22 is equal to or greater than the neutral point (“Yes” shown in the figure), the processing performed by the target deceleration calculation unit 30 proceeds to step S104.

On the other hand, if it is determined in step S100 that the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point ("No" shown in the figure), the processing performed by the target deceleration calculation unit 30 proceeds to step S106.
In step S104, the target deceleration is calculated as a deceleration reflecting the above-mentioned maximum deceleration constant regardless of the state of the vehicle V during travel ("maximum deceleration constant reflecting process" shown in the figure). I do. When the process of calculating the target deceleration as the deceleration reflecting the maximum deceleration constant is performed in step S104, the process performed by the target deceleration calculation unit 30 is ended (END).

  That is, in step S104, when acceleration (acceleration G) is generated in the vehicle V due to the driver's operation of the acceleration / deceleration pedal 22, the characteristics of the process for calculating the target deceleration are reset (initialized) to the above-described base characteristics. , Change). Alternatively, in step S104, when the driver who has stepped on the acceleration / deceleration pedal 22 releases his / her foot from the acceleration / deceleration pedal 22 and performs a brake operation, the process characteristic for calculating the target deceleration is reset to the base characteristic. I do.

  In step S106, the target deceleration is set as a deceleration reflecting the maximum deceleration setting value included in the maximum deceleration setting value signal received from the deceleration characteristic calculation unit 28 in accordance with the situation of the vehicle V during traveling. A calculation process ("deceleration characteristic reflection process" shown in the figure) is performed. In step S106, when the process of calculating the target deceleration as a deceleration reflecting the maximum deceleration set value included in the maximum deceleration set value signal is performed, the process performed by the target deceleration calculating unit 30 is ended (END). . In the following description, the process of calculating the target deceleration as the deceleration reflecting the maximum deceleration setting value included in the maximum deceleration setting value signal received from the deceleration characteristic calculation unit 28 is referred to as “deceleration”. May be described as “characteristic reflection processing”.

FIG. 7 is a flowchart showing the process performed in step S106, that is, the deceleration characteristic reflecting process.
As shown in FIG. 7, when the deceleration characteristic reflecting process is started (START), first, in step S200, a process of calculating the operation speed of the acceleration / deceleration pedal 22 ("accelerator operation speed calculation" shown in the figure) is performed. Do. If the process which calculates the operation speed of the acceleration / deceleration pedal 22 is performed in step S200, the deceleration characteristic reflection process will move to step S202.

Here, the operation speed of the acceleration / deceleration pedal 22 is calculated based on, for example, the pedal operation speed included in the pedal operation speed signal.
In step S202, a process of determining whether or not the operation speed of the acceleration / deceleration pedal 22 calculated in step S200 is equal to or higher than a preset step-up threshold (“accelerator operation speed ≧ step-up threshold” shown in the figure). Do.

Here, the stepping-in threshold value is a threshold value for determining whether or not the operation speed of the acceleration / deceleration pedal 22 is an operation speed in a direction in which the opening degree of the acceleration / deceleration pedal 22 is increased. This value corresponds to the operation speed of the acceleration / deceleration pedal 22.
In step S202, when it is determined that the operation speed of the acceleration / deceleration pedal 22 calculated in step S200 is greater than the threshold value (“Yes” shown in the figure), the deceleration characteristic reflecting process proceeds to step S204.

On the other hand, if it is determined in step S202 that the operation speed of the acceleration / deceleration pedal 22 calculated in step S200 is greater than the threshold value ("No" shown in the figure), the deceleration characteristic reflecting process proceeds to step S210. To do.
In step S204, in order to use for the process of calculating the target deceleration current value described later, a process of reflecting the above-described maximum deceleration setting value on a preset braking / driving force map ("maximum deceleration setting shown in the figure"). Value reflection processing)). When the process of reflecting the maximum deceleration set value in the braking / driving force map is performed in step S204, the deceleration characteristic reflecting process proceeds to step S206.

Here, the braking / driving force map is, for example, as shown in FIGS. 8A to 8C, the opening degree of the acceleration / deceleration pedal 22, the braking force and driving force generated in the vehicle V, and the driving margin. Is a map in which the relationship is set.
8A to 8C show the opening degree of the acceleration / deceleration pedal 22 and the braking force generated in the vehicle V when the driver performs an operation to increase the opening degree of the acceleration / deceleration pedal 22. And a map in which the relationship between the driving force and the driving margin is set. 8A to 8C, the vertical axis indicates the opening degree of the acceleration / deceleration pedal 22 (denoted as “pedal opening degree” in the drawing), and the horizontal axis indicates the driving margin (in the drawing). It is described as “horizontal G”).

Further, in FIGS. 8A to 8C, a region indicating a braking force and a driving force generated in the vehicle V in accordance with the relationship between the opening degree of the acceleration / deceleration pedal 22 and the driving margin is indicated by reference numeral A1. . 8A to 8C, the state where the opening degree of the acceleration / deceleration pedal 22 is the minimum value (pedal opening degree = 0) is indicated as “fully closed”, and the opening degree of the acceleration / deceleration pedal 22 is maximum. The value state is indicated as “fully open”.
Here, the driving margin is an area set according to at least one of the acceleration in the vehicle longitudinal direction and the vehicle width direction and the μ gradient generated in the vehicle V during traveling, and the traveling performance of the vehicle V This is an area before the limit area.

The driving margin is a region that decreases as the wheel grip value, which is a value corresponding to the grip performance of the wheel W, decreases. The grip performance of the wheel W is a force generated while the vehicle V is traveling, and is a value corresponding to the grip force (friction force) of the wheel W against the road surface.
In the example shown in FIG. 8, as an example, a case where the wheel grip value is an absolute value of acceleration in the vehicle width direction (lateral G) and the driving margin is set according to the size of the lateral G will be described. To do. Therefore, in the example shown in FIG. 8, a case will be described in which the wheel grip value decreases as the lateral G generated in the traveling vehicle V increases, and the driving margin decreases. This is because, when the absolute value of acceleration in the vehicle width direction exceeds the lateral G threshold value, the behavior of the vehicle V that is running, such as turning unintended by the driver, increases as the absolute value of acceleration in the vehicle width direction increases. This is because there is an increased possibility of occurrence. Here, the lateral G threshold corresponds to a preset wheel grip threshold. That is, a state where the absolute value of acceleration in the vehicle width direction exceeds the lateral G threshold corresponds to a state where the wheel grip value decreases and becomes less than a preset wheel grip threshold.

  FIGS. 8A to 8C show braking / driving force maps that change over time in the order of FIGS. 8A, 8B, and 8C. Specifically, FIG. 8B shows a state in which the absolute value of the acceleration in the vehicle width direction is increased without changing the opening degree of the acceleration / deceleration pedal 22 from the state of FIG. FIG. 8C shows a state in which the opening degree of the acceleration / deceleration pedal 22 is increased without changing the absolute value of the acceleration in the vehicle width direction from the state of FIG. 8B.

  That is, in step S204, when the process of reflecting the maximum deceleration set value is performed on the braking / driving force map shown in FIG. 8A, the braking / driving force map changes to the state shown in FIG. 8B. . Specifically, as shown in FIG. 9B, the vehicle V is generated from the state of FIG. 9A with the minimum opening of the acceleration / deceleration pedal 22 without changing the neutral point. Decrease the maximum deceleration value. Thereby, when the opening degree of the acceleration / deceleration pedal 22 is the minimum value, the braking force generated in the vehicle V is decreased from the value corresponding to the maximum deceleration constant (the value corresponding to the base characteristic).

  Therefore, when the process of step S204 is performed, the deceleration generated in the vehicle V according to the opening degree of the acceleration / deceleration pedal 22 is maximum in the braking / driving force map in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. Decreases compared to when processing to reflect the deceleration set value is not performed. For this reason, as shown in FIG.9 (c), compared with the case where the process of step S204 is not performed, the opening degree of the acceleration / deceleration pedal 22 is within the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. If it increases, the acceleration according to the increase in the opening degree of the acceleration / deceleration pedal 22 will increase.

That is, when the processing of step S204 is performed and the initial braking force command value is corrected to be small within the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, the correction is made small when the opening degree of the acceleration / deceleration pedal 22 increases. The braking force command value is set according to the initial braking force command value.
Here, the initial braking force command value is the maximum deceleration constant of the base characteristic described above. Therefore, if the process of reflecting the maximum deceleration setting value in the braking / driving force map is performed, the initial braking force command value is corrected to be small.

  9A to 9C are diagrams showing the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration generated in the vehicle V in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. It is. Further, in FIGS. 9A to 9C, the vertical axis indicates the deceleration generated in the vehicle V in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point (“deceleration” in the figure). ) And the horizontal axis indicates the opening of the acceleration / deceleration pedal 22 (denoted as “pedal opening” in the figure).

Further, in FIGS. 9A to 9C, the inclination indicating the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration is shown by a solid line. 9B and 9C, the relationship between the opening and deceleration of the acceleration / deceleration pedal 22 when the process for reflecting the maximum deceleration setting value in the braking / driving force map is not performed. The inclination indicating is shown by a broken line.
9A corresponds to FIG. 8A, FIG. 9B corresponds to FIG. 8B, and FIG. 9C corresponds to FIG. 8C.

  In step S206, using the braking / driving force map reflecting the maximum deceleration setting value, a process of calculating the current value of the target deceleration (target deceleration current value) ("target deceleration current value calculation shown in the figure"). Process "). In step S206, when the process of calculating the target deceleration current value using the braking / driving force map reflecting the maximum deceleration setting value is performed, the deceleration characteristic reflecting process proceeds to step S208.

  In step S208, the target deceleration current value calculated in step S206 is compared with the target deceleration (target deceleration previous value) calculated in the previous deceleration characteristic reflection process. Then, a process of selecting the minimum value among the current target deceleration value and the previous target deceleration value as the target deceleration calculated in this process (“MIN (target deceleration current value, target deceleration previous value shown in the figure) Value))). In step S208, when the process of selecting the target deceleration calculated in the current process is performed, the deceleration characteristic reflection process is terminated (END).

In step S210, a process for determining whether or not the target deceleration (target deceleration previous value) calculated in the previous deceleration characteristic reflecting process is equal to or greater than the maximum deceleration set value described above ("target" shown in the figure). “Deceleration previous value ≥ Maximum deceleration setting value”).
If it is determined in step S210 that the previous target deceleration value is greater than or equal to the maximum deceleration set value ("Yes" shown in the figure), the deceleration characteristic reflecting process proceeds to step S212.

On the other hand, if it is determined in step S210 that the previous target deceleration value is less than the maximum deceleration set value ("No" shown in the figure), the deceleration characteristic reflecting process proceeds to step S214.
In step S212, a process of calculating a target deceleration (“target deceleration calculation process” shown in the figure) is performed based on the previous target deceleration value. In step S212, when the process of calculating the target deceleration based on the previous target deceleration value is performed, the deceleration characteristic reflecting process is terminated (END).

  In step S214, the provisional target deceleration is based on the opening degree of the acceleration / deceleration pedal 22 used in the process of step S100 and the target deceleration (target deceleration previous value) calculated in the previous deceleration characteristic reflection process. (A “target deceleration provisional value calculation process” shown in the drawing) is performed. In step S214, when the process of calculating the provisional target deceleration is performed, the deceleration characteristic reflecting process proceeds to step S216.

In step S216, a process for determining whether or not the target deceleration (target deceleration previous value) calculated in the previous deceleration characteristic reflecting process is equal to or greater than the tentative target deceleration calculated in step S214 (in the figure). “Target deceleration previous value ≧ Target deceleration provisional value”) shown in FIG.
If it is determined in step S216 that the previous target deceleration value is equal to or greater than the target deceleration provisional value ("Yes" shown in the figure), the deceleration characteristic reflecting process proceeds to step S218.

On the other hand, when it is determined in step S216 that the previous target deceleration value is less than the target deceleration provisional value ("No" shown in the figure), the deceleration characteristic reflecting process proceeds to step S220.
In step S218, a process of reflecting the maximum deceleration set value in the braking / driving force map ("maximum deceleration set value reflecting process" shown in the drawing) is performed for use in the process of calculating the target deceleration current value. When the process of reflecting the maximum deceleration set value in the braking / driving force map is performed in step S218, the deceleration characteristic reflecting process proceeds to step S220.

Therefore, when the processing of step S218 is performed, the acceleration / deceleration pedal is increased when the opening of the acceleration / deceleration pedal 22 is increased in the range where the opening of the acceleration / deceleration pedal 22 is less than the neutral point, as in the case of performing the processing of step S204. The acceleration corresponding to the increase in the opening degree of 22 increases.
In step S220, when the process of step S218 is performed (when the determination result of step S216 is “Yes”), similarly to step S206, a process of calculating the target deceleration current value (the “target deceleration shown in the figure”). Current value calculation process "). Specifically, the target deceleration current value is calculated using a braking / driving force map reflecting the maximum deceleration setting value. On the other hand, when the process of step S218 is not performed (when the determination result of step S216 is “No”), the target deceleration current value is calculated based on the previous target deceleration value (the “target deceleration shown in the figure”). Current speed calculation processing ") is performed. When the process of calculating the target deceleration current value is performed in step S220, the deceleration characteristic reflecting process proceeds to step S222.

  In step S222, the target deceleration current value calculated in step S220 is compared with the target deceleration (target deceleration previous value) calculated in the previous deceleration characteristic reflection process. Then, a process of selecting the maximum value among the target deceleration current value and the target deceleration previous value as the target deceleration calculated in this process (“MAX (target deceleration current value, target deceleration previous value shown in the figure) Value))). In step S222, when the process of selecting the target deceleration calculated in the current process is performed, the deceleration characteristic reflection process is terminated (END).

  As described above, in step S202, when it is determined that the operation speed of the acceleration / deceleration pedal 22 calculated in step S200 is greater than or equal to the threshold value, it is determined that the driver is depressing the acceleration / deceleration pedal 22. It is determined that the driver's intention is an acceleration intention. In the processing performed from step S202 through step S204, step S206, and step S208, the target deceleration is immediately changed to the characteristic deceleration reflecting the maximum deceleration set value according to the driver's intention to accelerate. Process to change to.

In this case, in the process of step S208, the minimum value of the current target deceleration value and the previous target deceleration value is selected as the target deceleration calculated in the current process. This is to suppress an increase in the deceleration generated in the vehicle V due to the driver's depressing operation of the acceleration / deceleration pedal 22 in a range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point.
In step S202, when it is determined that the operation speed of the acceleration / deceleration pedal 22 calculated in step S200 is greater than the threshold, the driver performs an operation to maintain or decrease the opening degree of the acceleration / deceleration pedal 22. It is determined that Thereby, it is determined that the driver's intention is a vehicle speed maintenance intention or a deceleration intention.

In the processing performed from step S202 via step S210 and step S212, the deceleration that is equal to or greater than the maximum deceleration set value is used, so the target deceleration is calculated based on the previous target deceleration value. .
That is, when the lateral G exceeds the lateral G threshold, the braking force command value set according to the opening degree of the acceleration / deceleration pedal 22 is set to the braking force command value set according to the initial braking force command value corrected to be small. If exceeded, the initial braking force command value is held.

On the other hand, in the processing performed from step S202 via steps S210 and S214, when the target deceleration provisional value is larger than the previous target deceleration value, the target deceleration is reflected on the maximum deceleration set value. A process to immediately change to the deceleration of the characteristic that does not.
Further, in the process in which the target deceleration calculating unit 30 calculates the target deceleration, the process of reflecting the maximum deceleration setting value in the braking / driving force map is performed, so that the vehicle V is adjusted according to the opening degree of the acceleration / deceleration pedal 22. Reduces the generated deceleration. For this reason, when the driver performs an operation to reduce the opening degree of the acceleration / deceleration pedal 22 in a range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, the vehicle V is included in the opening degree of the acceleration / deceleration pedal 22. It is possible to eliminate a range where no deceleration occurs (see FIGS. 10 and 11). As a result, the intention of deceleration by the driver can be reflected in the behavior of the vehicle V in the entire range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point.

  10A to 10C show the opening degree of the acceleration / deceleration pedal 22 and the braking force generated in the vehicle V when the driver performs an operation to reduce the opening degree of the acceleration / deceleration pedal 22. And a map in which the relationship between the driving force and the driving margin is set. 10 (a) to 10 (c), the vertical axis indicates the opening degree of the acceleration / deceleration pedal 22 (denoted as “pedal opening degree” in the figure), and the horizontal axis indicates the driving margin (in the figure). It is described as “horizontal G”).

Further, in FIGS. 10A to 10C, a region indicating the braking force and driving force generated in the vehicle V in accordance with the relationship between the opening degree of the acceleration / deceleration pedal 22 and the driving margin is indicated by reference numeral A1. . Further, in FIGS. 10A to 10C, the state where the opening degree of the acceleration / deceleration pedal 22 is the minimum value (pedal opening degree = 0) is indicated as “fully closed”, and the opening degree of the acceleration / deceleration pedal 22 is maximum. The value state is indicated as “fully open”.
FIGS. 10A to 10C show braking / driving force maps that change over time in the order of FIGS. 10A, 10B, and 10C. Specifically, FIG. 10B shows a state in which the absolute value of the acceleration in the vehicle width direction is increased without changing the opening degree of the acceleration / deceleration pedal 22 from the state of FIG. FIG. 10C shows a state in which the opening degree of the acceleration / deceleration pedal 22 is decreased without changing the absolute value of the acceleration in the vehicle width direction from the state of FIG. 10B.

  11A to 11C are diagrams showing the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration generated in the vehicle V in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. It is. Further, in FIGS. 11A to 11C, the vertical axis indicates the deceleration generated in the vehicle V in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point (“deceleration” in the figure). ) And the horizontal axis indicates the opening of the acceleration / deceleration pedal 22 (denoted as “pedal opening” in the figure).

Further, in FIGS. 11A to 11C, the inclination indicating the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration is shown by a solid line. Further, in FIGS. 11B and 11C, the relationship between the opening degree and the deceleration of the acceleration / deceleration pedal 22 when the process of reflecting the maximum deceleration setting value is not performed in the braking / driving force map. The inclination indicating is shown by a broken line.
Further, FIG. 11 (a) corresponds to FIG. 10 (a), FIG. 11 (b) corresponds to FIG. 10 (b), and FIG. 11 (c) corresponds to FIG.

Therefore, in the present embodiment, if the initial braking force command value is corrected to be small within the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, the initial control value that is corrected to be small is reduced when the opening degree of the acceleration / deceleration pedal 22 decreases. The braking force command value is set according to the power command value.
Further, in the process in which the target deceleration calculating unit 30 calculates the target deceleration, the process of reflecting the maximum deceleration setting value in the braking / driving force map is performed, so that the vehicle V is adjusted according to the opening degree of the acceleration / deceleration pedal 22. Reduces the generated deceleration. For this reason, when the driver performs an operation to maintain the opening degree of the acceleration / deceleration pedal 22 in a range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, the vehicle V is included in the opening degree of the acceleration / deceleration pedal 22. It is possible to eliminate the range where the deceleration does not occur (see FIGS. 12 and 13). As a result, the intention of deceleration by the driver can be reflected in the behavior of the vehicle V in the entire range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point.

  12 (a) to 12 (c) show the opening degree of the acceleration / deceleration pedal 22 and the braking force generated in the vehicle V in a state in which the operation of holding the opening degree of the acceleration / deceleration pedal 22 by the driver is performed. And a map in which the relationship between the driving force and the driving margin is set. 12 (a) to 12 (c), the vertical axis represents the opening degree of the acceleration / deceleration pedal 22 (denoted as “pedal opening degree” in the figure), and the horizontal axis represents the driving margin (in the figure). It is described as “horizontal G”).

In FIGS. 12A to 12C, a region indicating the braking force and driving force generated in the vehicle V in accordance with the relationship between the opening degree of the acceleration / deceleration pedal 22 and the driving margin is indicated by reference numeral A1. . Also, in FIGS. 12A to 12C, the state where the opening degree of the acceleration / deceleration pedal 22 is the minimum value (pedal opening degree = 0) is indicated as “fully closed”, and the opening degree of the acceleration / deceleration pedal 22 is maximum. The value state is indicated as “fully open”.
12A to 12C show braking / driving force maps that change over time in the order of FIGS. 12A, 12B, and 12C. Specifically, FIG. 12B shows a state in which the absolute value of the acceleration in the vehicle width direction is increased without changing the opening degree of the acceleration / deceleration pedal 22 from the state of FIG. FIG. 12C shows a state in which the opening degree of the acceleration / deceleration pedal 22 is reduced without changing the absolute value of the acceleration in the vehicle width direction from the state of FIG.

  FIGS. 13A to 13C are diagrams showing the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration generated in the vehicle V in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. It is. Further, in FIGS. 13A to 13C, the vertical axis indicates the deceleration generated in the vehicle V in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point (“deceleration” in the figure). ) And the horizontal axis indicates the opening of the acceleration / deceleration pedal 22 (denoted as “pedal opening” in the figure).

In FIGS. 13A to 13C, a solid line indicates the inclination indicating the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration. 13B and 13C, the relationship between the opening and deceleration of the acceleration / deceleration pedal 22 when the process for reflecting the maximum deceleration setting value is not performed in the braking / driving force map. The inclination indicating is shown by a broken line.
FIG. 13A corresponds to FIG. 12A, FIG. 13B corresponds to FIG. 12B, and FIG. 13C corresponds to FIG. 12C.

Therefore, in the present embodiment, the opening degree of the acceleration / deceleration pedal 22 decreases until the opening degree according to the initial braking force command value corrected to be smaller than the opening degree corresponding to the initial braking force command value before correction is reached. The braking force command value is set so as to maintain the braking force generated in the vehicle V.
In addition, in the process in which the target deceleration calculation unit 30 calculates the target deceleration, the brake operation amount signal is input from the brake operation amount sensor 4 in a state in which the maximum deceleration set value is reflected in the braking / driving force map. If it is received, the following processing is performed. That is, when the driver depresses the brake pedal 24 in a state where the maximum deceleration set value is reflected in the braking / driving force map, for example, as shown in FIG. A target deceleration is calculated based only on the stepping operation amount of 24.

  14 (a) to 14 (c) show the opening degree of the acceleration / deceleration pedal 22 and the brake pedal 24 in the state where the depression operation of the brake pedal 24 by the driver is performed, and the control generated by the vehicle V. It is the map which set the relationship between motive power and driving force, and driving margin. Further, in FIGS. 14A to 14C, the left vertical axis indicates the opening degree of the acceleration / deceleration pedal 22 (described as “accelerator opening degree” in the figure), and the right vertical axis indicates the brake pedal. 24 (denoted as “brake opening” in the figure). Similarly, in FIGS. 14A to 14C, the horizontal axis indicates the driving margin (denoted as “horizontal G” in the figure).

Further, in FIGS. 14A to 14C, a region indicating a braking force and a driving force generated in the vehicle V in accordance with the relationship between the opening degree of the acceleration / deceleration pedal 22 and the driving margin is indicated by reference numeral A1. . Further, in FIGS. 14A to 14C, a state where the opening degree of the acceleration / deceleration pedal 22 is the minimum value (pedal opening degree = 0) is indicated as “fully closed”, and the opening degree of the acceleration / deceleration pedal 22 is the maximum. The value state is indicated as “fully open”.
Similarly, in FIGS. 14A to 14C, a region indicating only the driving force generated in the vehicle V in accordance with the opening degree of the brake pedal 24 is indicated by reference numeral A2. 14A to 14C, the state where the opening degree of the brake pedal 24 is the minimum value (pedal opening degree = 0) is indicated as “fully closed”.

14A to 14C show braking / driving force maps that change over time in the order of FIGS. 14A, 14B, and 14C. Specifically, FIG. 14B shows a state in which the absolute value of acceleration in the vehicle width direction has increased from the state of FIG. FIG. 14C shows a state in which the absolute value of acceleration in the vehicle width direction has increased from the state of FIG. 14B.
That is, in the present embodiment, by performing the process of reflecting the maximum deceleration set value in the braking / driving force map, only the degree of change in the deceleration generated in the vehicle V is changed according to the opening degree of the acceleration / deceleration pedal 22. The degree of change in acceleration is not changed.

  This is because, in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, when the deceleration generated in the vehicle V by the operation of the acceleration / deceleration pedal 22 is insufficient for the driver's intention to decelerate, the brake pedal 24 is operated. This is because it becomes possible to compensate for the deceleration of the shortage. In this case, the operation of the brake pedal 24 may correspond to an emergency braking operation (brake operation).

  On the other hand, if the acceleration generated in the vehicle V by the operation of the acceleration / deceleration pedal 22 is insufficient for the driver's intention to accelerate in the range where the opening degree of the acceleration / deceleration pedal 22 is equal to or greater than the neutral point, the depression amount of the acceleration / deceleration pedal 22 is set. By increasing it, it becomes possible to compensate for the insufficient acceleration. For this reason, even if it is a case where the process which reflects the maximum deceleration setting value on a braking / driving force map is performed, the change degree of acceleration is not changed. In this case, the operation for increasing the depression amount of the acceleration / deceleration pedal 22 may correspond to an emergency acceleration operation (rapid acceleration operation).

  As described above, in the braking / driving force control device 1 according to the present embodiment, when the absolute value (lateral G) of acceleration in the vehicle width direction increases and the driving margin decreases, the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. In this range, the inclination indicating the relationship between the opening degree of the acceleration / deceleration pedal 22 and the deceleration is changed. Thereby, the deceleration generated in the vehicle V is reduced according to the opening degree of the acceleration / deceleration pedal 22 in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. For this reason, in the range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, the resolution of the deceleration generated in the vehicle V with respect to the opening degree of the acceleration / deceleration pedal 22 can be improved.

  That is, in the braking / driving force control device 1 of the present embodiment, when the lateral G detected by the G sensor 6 exceeds the lateral G threshold, the deceleration characteristic calculating unit 28 and the target deceleration calculating unit 30 The initial braking force command value is corrected to be small according to the deviation from the lateral G threshold. Specifically, when the lateral G detected by the G sensor 6 exceeds the lateral G threshold when the deceleration characteristic calculating unit 28 and the target deceleration calculating unit 30 exceed the lateral G threshold, the deviation between the detected lateral G and the lateral G threshold increases. The initial braking force command value is corrected to be small.

In the above description, as an example, the case where the wheel grip value is set to the lateral G and the driving margin is set according to the size of the lateral G is described. However, the wheel grip value is not limited to the lateral G. Absent. That is, the wheel grip value may be set to μ gradient, and the driving margin may be set according to the size of the μ gradient. In this case, the smaller the μ gradient generated in the traveling vehicle V is, the smaller the wheel grip value is and the driving margin is reduced. This is because when the μ gradient is less than the μ gradient threshold, the possibility that the wheel W slips or the like increases as the μ gradient decreases. This is because the possibility of occurrence of behavior increases. In this case, the μ gradient threshold value corresponds to a preset wheel grip threshold value. That is, the state in which the μ gradient is less than the μ gradient threshold corresponds to a state in which the wheel grip value decreases and becomes less than a preset wheel grip threshold.
Further, the wheel grip value may be set to the lateral G and μ gradient, and the driving margin may be set according to the magnitude of the lateral G and μ gradient. In this case, as the lateral G generated in the traveling vehicle V increases and the μ gradient decreases, the wheel grip value decreases and the driving margin decreases.

(Operation)
Next, an example of an operation performed using the braking / driving force control device 1 of the present embodiment will be described with reference to FIGS. 1 to 14 and FIG.
FIG. 15 is a flowchart of operations performed using the braking / driving force control device 1 of the present embodiment.

  As shown in FIG. 15, when the operation performed using the braking / driving force control device 1 is started (START), first, in step S300, the opening degree (operation amount) of the acceleration / deceleration pedal 22 by the driver is detected. ("Dr accelerator pedal operation amount detection" shown in the figure) is performed. If the process which detects the opening degree of the acceleration / deceleration pedal 22 is performed in step S300, the operation | movement performed using the braking / driving force control apparatus 1 will transfer to step S302.

In step S302, processing for acquiring the state of the vehicle V (μ gradient, acceleration in the lateral direction of the vehicle body (lateral G), acceleration in the longitudinal direction of the vehicle body (front and rear G)) ("vehicle state acquisition" shown in the figure). )I do. If the process which acquires the state of the vehicle V is performed in step S302, the operation | movement performed using the braking / driving force control apparatus 1 will transfer to step S304.
In step S304, processing for calculating a maximum deceleration setting value ("maximum deceleration setting value calculation" shown in the figure) is performed. If the process which calculates the maximum deceleration setting value is performed in step S304, the operation | movement performed using the braking / driving force control apparatus 1 will transfer to step S306.

In step S306, processing for calculating the depression operation amount of the acceleration / deceleration pedal 22 with reference to the neutral point ("acceleration opening calculation for braking / driving force calculation" shown in the figure) is performed. In step S306, when the process of calculating the depression operation amount of the acceleration / deceleration pedal 22 based on the neutral point is performed, the operation performed using the braking / driving force control device 1 proceeds to step S306.
In step S308, processing for calculating the target deceleration ("target deceleration calculation" shown in the figure) is performed. If the process which calculates target deceleration is performed in step S308, the operation | movement performed using the braking / driving force control apparatus 1 will transfer to step S310.

In step S310, a process for calculating a driving force command value ("driving force command value calculation" shown in the figure) is performed. If the process which calculates a driving force command value is performed in step S310, the operation | movement performed using the braking / driving force control apparatus 1 will transfer to step S312.
In step S312, a process for calculating a braking force command value ("braking force command value calculation" shown in the figure) is performed. If the process which calculates braking force command value is performed in step S312, the operation | movement performed using the braking / driving force control apparatus 1 will be complete | finished (END).

The acceleration / deceleration pedal 22 described above corresponds to a braking / driving force operator.
The accelerator operation amount sensor 2 described above corresponds to an operation element operation amount detection unit.
The braking / driving force controller 12 described above corresponds to a braking / driving force control unit.
The deceleration characteristic calculation unit 28 described above corresponds to a wheel grip value detection unit.
The target deceleration calculating unit 30 described above corresponds to an initial braking force command value correcting unit.

Further, the absolute value of the acceleration in the vehicle width direction (absolute value of the lateral G) included in the measured lateral acceleration signal described above and the μ gradient included in the road surface μ signal correspond to the wheel grip value.
Further, the lateral G threshold and the μ gradient threshold described above correspond to the wheel grip threshold.
The G sensor 6 described above corresponds to a vehicle width direction acceleration detection unit.
The wheel speed sensor 8 and the μ gradient calculation unit 10 described above correspond to a μ gradient detection unit.

  Further, as described above, in the braking / driving force control method implemented by the operation of the braking / driving force control device 1 of the present embodiment, the wheel has a value corresponding to the opening degree of the acceleration / deceleration pedal 22 and the grip performance of the wheel W. Detect grip value. When the detected wheel grip value is less than the preset wheel grip threshold, the greater the deviation between the detected behavior and the wheel grip threshold, the greater the deceleration rate of the base characteristic described above in the braking range below the neutral point. A certain initial braking force command value is corrected to be small.

(Effects of the first embodiment)
If it is the braking / driving force control apparatus 1 of this embodiment, it will become possible to show the effect described below.
(1) When the wheel deceleration value (absolute value of lateral G, μ gradient) is less than the wheel grip threshold value (lateral G threshold value, μ gradient threshold value), the target deceleration calculation unit 30 generates a wheel within a braking range less than the neutral point. The larger the deviation between the grip value and the wheel grip threshold, the smaller the initial braking force command value is corrected.
For this reason, when the grip performance of the wheel W is reduced and the wheel grip value becomes less than the wheel grip threshold, the larger the deviation between the wheel grip value and the wheel grip threshold, the smaller the decrease in the opening of the acceleration / deceleration pedal 22 in the braking range. It is possible to reduce the degree of change in speed.

  As a result, the amount of increase in the deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 is decreased within the braking range less than the neutral point, and the driver who is predicted to cause unstable behavior due to the increase in the deceleration is decelerated. It is possible to make it easy to actively perform the operation. That is, even when the grip performance of the wheel W is lowered during the traveling of the vehicle V, the driver who predicts that the unstable behavior is caused by the increase in the deceleration is actively performed on the deceleration. It becomes possible to make it easier.

In addition, since the degree of change in deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 can be reduced in a braking range less than the neutral point, the deceleration generated in the vehicle V with respect to the opening degree of the acceleration / deceleration pedal 22 can be reduced. The resolution can be improved.
Thereby, compared with the case where the change degree of the deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 is not changed, the opening degree of the acceleration / deceleration pedal 22 for maintaining the deceleration generated in the vehicle V within a certain range is set. The operation to maintain becomes easy. Further, the deceleration generated by the vehicle V can be easily adjusted by operating the acceleration / deceleration pedal 22 as compared with the case where the degree of change of the deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 is not changed.
Further, since the relationship between the opening degree of the acceleration / deceleration pedal 22 and the acceleration generated in the vehicle V in the driving range equal to or higher than the neutral point is not changed, it is possible to suppress a decrease in acceleration performance at the time of reacceleration.

(2) When the braking / driving force controller 12 corrects the initial braking force command value to a small value within the braking range in which the target deceleration calculation unit 30 opens the acceleration / deceleration pedal 22 below the neutral point, the opening of the acceleration / deceleration pedal 22 Is increased, the braking force command value is set according to the initially corrected initial braking force command value.
For this reason, when the opening degree of the acceleration / deceleration pedal 22 is increased in the braking range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point, the acceleration corresponding to the increase in the opening degree of the acceleration / deceleration pedal 22 can be increased. It becomes.
As a result, in the driving range where the opening degree of the acceleration / deceleration pedal 22 is equal to or greater than the neutral point, when the acceleration generated in the vehicle V due to the operation of the acceleration / deceleration pedal 22 is insufficient for the intention of acceleration, the depression amount of the acceleration / deceleration pedal 22 is increased. This makes it possible to compensate for the shortage of acceleration.

(3) When the braking / driving force controller 12 corrects the initial braking force command value to be small within the braking range in which the target deceleration calculation unit 30 has the opening of the acceleration / deceleration pedal 22 less than the neutral point, the opening of the acceleration / deceleration pedal 22 Is reduced, the braking force command value is set in accordance with the initially corrected initial braking force command value.
For this reason, in the braking range less than the neutral point, it is possible to eliminate the range in which the deceleration of the vehicle V does not occur in the opening degree of the acceleration / deceleration pedal 22.
As a result, the driver's intention to decelerate can be reflected in the behavior of the vehicle V in the entire braking range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point.

(4) When the braking / driving force controller 12 corrects the initial braking force command value so that the target deceleration calculation unit 30 maintains a constant value within a braking range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point. The braking force command value is set as follows. That is, it is generated in the vehicle V until the opening degree of the acceleration / deceleration pedal 22 decreases and becomes the opening degree corresponding to the initial braking force command value corrected to be smaller than the opening degree corresponding to the initial braking force command value before correction. A braking force command value is set so as to maintain the braking force.
For this reason, in the braking range less than the neutral point, it is possible to eliminate the range in which the deceleration of the vehicle V does not occur in the opening degree of the acceleration / deceleration pedal 22.
As a result, the driver's intention to decelerate can be reflected in the behavior of the vehicle V in the entire braking range where the opening degree of the acceleration / deceleration pedal 22 is less than the neutral point.

(5) When the target deceleration calculation unit 30 exceeds the braking force command value set according to the initial braking force command value corrected to be small, the braking force command value set according to the opening degree of the acceleration / deceleration pedal 22 The initial braking force command value is held. This process is performed when the wheel grip value (absolute value of lateral G, μ gradient) becomes less than the wheel grip threshold (lateral G threshold, μ gradient threshold).
As a result, it is possible to suppress a decrease in braking force generated in the vehicle V in response to the driver's intention to decelerate.

(6) The deceleration characteristic calculation unit 28 detects the absolute value of the acceleration in the vehicle width direction, which is the wheel grip value, based on the acceleration (lateral G) detected by the G sensor 6.
As a result, it is possible to detect the wheel grip value, which is a value corresponding to the grip performance of the wheel W, based on the possibility that a behavior such as turning that the driver does not intend occurs in the traveling vehicle V. .

(7) The deceleration characteristic calculation unit 28 detects a μ gradient that is a wheel grip value based on the μ gradient detected by the wheel speed sensor 8 and the μ gradient calculation unit 10.
As a result, the wheel grip value, which is a value according to the grip performance of the wheel W, may cause a slip of the wheel W, and the vehicle V that is running will behave such as braking failure unintended by the driver. It becomes possible to detect based on the possibility of doing.

(8) The vehicle width that is the wheel grip value based on the acceleration (lateral G) detected by the G sensor 6 and the μ gradient detected by the wheel speed sensor 8 and the μ gradient calculating unit 10 by the deceleration characteristic calculating unit 28. Detect absolute value of acceleration in direction and μ gradient.
As a result, the wheel grip value is set to the traveling vehicle V, such as the possibility of a behavior such as turning unintended by the driver, the possibility of the wheel W slipping, and the like. It becomes possible to detect based on the possibility of occurrence of behavior such as braking failure unintended by the driver.

(9) In the braking / driving force control method implemented by the operation of the braking / driving force control device 1 of the present embodiment, when the wheel grip value is less than the wheel grip threshold, the wheel grip value and the wheel grip are within the braking range less than the neutral point. The larger the deviation from the threshold, the smaller the initial braking force command value is corrected.
For this reason, when the grip performance of the wheel W is reduced and the wheel grip value becomes less than the wheel grip threshold, the larger the deviation between the wheel grip value and the wheel grip threshold, the smaller the decrease in the opening of the acceleration / deceleration pedal 22 in the braking range. It is possible to reduce the degree of change in speed.
As a result, the amount of increase in the deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 is decreased within the braking range less than the neutral point, and the driver who is predicted to cause unstable behavior due to the increase in the deceleration is decelerated. It is possible to make it easy to actively perform the operation. That is, even when the grip performance of the wheel W is lowered during the traveling of the vehicle V, the driver who predicts that the unstable behavior is caused by the increase in the deceleration is actively performed on the deceleration. It becomes possible to make it easier.

In addition, since the degree of change in deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 can be reduced in a braking range less than the neutral point, the deceleration generated in the vehicle V with respect to the opening degree of the acceleration / deceleration pedal 22 can be reduced. The resolution can be improved.
Thereby, compared with the case where the change degree of the deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 is not changed, the opening degree of the acceleration / deceleration pedal 22 for maintaining the deceleration generated in the vehicle V within a certain range is set. The operation to maintain becomes easy. Further, the deceleration generated by the vehicle V can be easily adjusted by operating the acceleration / deceleration pedal 22 as compared with the case where the degree of change of the deceleration with respect to the opening degree of the acceleration / deceleration pedal 22 is not changed.
Further, since the relationship between the opening degree of the acceleration / deceleration pedal 22 and the acceleration generated in the vehicle V in the driving range equal to or higher than the neutral point is not changed, it is possible to suppress a decrease in acceleration performance at the time of reacceleration.

(Modification)
(1) In this embodiment, although the power unit 20 was formed using the engine, the structure of the power unit 20 is not limited to this. That is, the power unit 20 may be formed using, for example, a motor, or may be formed using an engine and a motor.
(2) In the present embodiment, the braking / driving force operator is the acceleration / deceleration pedal 22 that the driver steps on with his / her foot, but the configuration of the braking / driving force operator is not limited to this. That is, for example, the braking / driving force operator may be a lever that is manually operated by the driver.

DESCRIPTION OF SYMBOLS 1 Braking / driving force control apparatus 2 Accelerator operation amount sensor 4 Brake operation amount sensor 6 G sensor 8 Wheel speed sensor 10 μ gradient calculation part 12 Braking / driving force controller 14 Brake actuator 16 Wheel cylinder 18 Power control unit 20 Power unit 22 Acceleration / deceleration pedal 24 Brake Pedal 26 Braking / Driving Force Calculation Pedal Opening Calculation Unit 28 Deceleration Characteristic Calculation Unit 30 Target Deceleration Calculation Unit 32 Driving Force Calculation Unit 34 Braking Force Calculation Unit 36 Maximum Deceleration First Correction Coefficient Calculation Unit 38 Maximum Decrease Second speed correction coefficient calculation unit 40 Selection deceleration constant generation unit 42 Deceleration characteristic setting unit V Vehicle

Claims (9)

A braking / driving force control device that sets a braking force command value that is a braking force command value generated in a vehicle or a driving force command value that is a driving force command value according to an operation amount of a braking / driving force operator,
An operation amount detector for detecting an operation amount of the braking / driving force operator;
In a braking range in which the operation amount detected by the operation element operation amount detection unit is less than a predetermined operation amount from an unoperated state, an initial braking force in which the braking force command value is set in advance according to the increase in the detected operation amount. Braking / driving force control for setting the driving force command value according to a deviation between the predetermined operation amount and the detected operation amount in a driving range in which the detected operation amount is equal to or greater than the predetermined operation amount. And
A wheel grip value detection unit that detects a wheel grip value that is a value according to the grip performance of the wheel;
An initial braking force command value correcting unit that corrects the initial braking force command value in the braking range according to a wheel grip value detected by the wheel grip value detecting unit,
When the wheel grip value detected by the wheel grip value detection unit is less than a preset wheel grip threshold, the initial braking force command value correction unit increases the deviation between the detected wheel grip value and the wheel grip threshold. The braking / driving force control apparatus corrects the initial braking force command value to be small.   When the operation amount detected by the operation element operation amount detection unit is within the braking range and the initial braking force command value correction unit corrects the initial braking force command value to be small, the braking / driving force control unit 2. The braking / driving force control device according to claim 1, wherein the braking force command value is set in accordance with the small corrected initial braking force command value when the operation amount detected by the amount detection unit increases. .   When the operation amount detected by the operation element operation amount detection unit is within the braking range and the initial braking force command value correction unit corrects the initial braking force command value to be small, the braking / driving force control unit 3. The control according to claim 1, wherein the braking force command value is set according to the initial braking force command value corrected to be small when the operation amount detected by the amount detection unit decreases. Driving force control device.   The braking / driving force control unit is configured such that the initial braking force command value correcting unit sets the initial braking force command value in a state where the operation amount detected by the operator operation amount detecting unit is maintained at a constant value within the braking range. When the correction is made smaller, the operation amount detected by the operation element operation amount detection unit decreases, and the operation amount according to the initial braking force command value corrected to be smaller is changed from the operation amount according to the initial braking force command value before correction. The braking / driving force control device according to any one of claims 1 to 3, wherein the braking force command value is set so as to maintain a braking force generated in the vehicle.   The initial braking force command value correction unit is set according to the operation amount detected by the operator operation amount detection unit when the wheel grip value detected by the wheel grip value detection unit becomes less than the wheel grip threshold. The initial braking force command value is held when a braking force command value to be exceeded exceeds a braking force command value set according to the small corrected initial braking force command value. 4. The braking / driving force control device according to claim 1. A vehicle width direction acceleration detection unit that detects a lateral acceleration of a vehicle body generated in the vehicle;
The said wheel grip value detection part detects the said wheel grip value based on the acceleration which the said vehicle width direction acceleration detection part detected, The any one of Claims 1-5 characterized by the above-mentioned. Braking / driving force control device. A μ gradient detection unit that detects a μ gradient that is a rate of change in lateral force of the wheel with respect to a change amount of a slip angle of the wheel of the vehicle;
The said wheel grip value detection part detects the said wheel grip value based on (micro | micron | mu) gradient which the said [mu] gradient detection part detected, It described in any one of Claims 1-5 characterized by the above-mentioned. Braking / driving force control device. A vehicle width direction acceleration detector for detecting lateral acceleration of the vehicle body generated in the vehicle;
A μ gradient detector that detects a μ gradient that is a rate of change of the lateral force of the wheel with respect to a change amount of a slip angle of the wheel of the vehicle, and
The wheel grip value detection unit detects the wheel grip value based on the acceleration detected by the vehicle width direction acceleration detection unit and the μ gradient detected by the μ gradient detection unit. The braking / driving force control device according to any one of claims 1 to 5. A braking / driving force control method for setting a braking force command value, which is a braking force command value to be generated in a vehicle according to an operation amount of a braking / driving force operator, or a driving force command value, which is a driving force command value,
Detecting the operation amount of the braking / driving force operator,
In a braking range in which the detected operation amount is less than a predetermined operation amount from an unoperated state, the braking force command value is decreased from a preset initial braking force command value in accordance with an increase in the detected operation amount, In the driving range in which the detected operation amount is equal to or greater than the predetermined operation amount, the driving force command value according to a deviation between the predetermined operation amount and the detected operation amount is set,
Detect the wheel grip value, which is a value according to the grip performance of the wheel,
When the detected wheel grip value is less than a preset wheel grip threshold, the initial braking force command value is corrected to be smaller in the braking range as the deviation between the detected wheel grip value and the wheel grip threshold is larger. A braking / driving force control method characterized by the above.

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