JP5895368B2 - Braking / driving force control device and braking / driving force control method - Google Patents

Description

  The present invention relates to a braking / driving force control device and a braking / driving force control method for an automobile.

Conventionally, as this type of technology, for example, there is a technology described in Patent Document 1.
In the technique described in Patent Document 1, the camber angle is adjusted by providing two types of parts on the tread surface of the wheel, a part having a high gripping force and a part having a characteristic of low rolling resistance that is a contradictory characteristic. These two types of tread surfaces are used properly.
As a result, it is intended to achieve both the securing of traveling performance using characteristics with high grip force and fuel saving using characteristics with low rolling resistance.

JP 2010-221990 A

However, in the technique described in Patent Document 1, it is necessary to have both a special tire (a tire having a tread having different characteristics) and a mechanism for adjusting the camber angle. In addition, the technique described in Patent Document 1 is intended only to achieve both driving performance and fuel saving, and does not improve other performance. Furthermore, depending on the relationship between the state of the traveling road and the selected tread surface, there is a possibility that the ride comfort may be reduced or the fuel efficiency may be reduced.
That is, in the conventional technology, it has been difficult to achieve both improvement in fuel efficiency, steering stability, and riding comfort performance.
The subject of this invention is aiming at coexistence with the improvement of a fuel consumption, steering stability, and riding comfort performance.

To solve the above problems, the present invention, among the components constituting the sprung behavior of the vehicle body estimated fuel consumption as compared with the case of setting lower the suppression level by high rather sets the degree of suppression of the pitch fluctuation component Based on the fuel efficiency improvement mode for improving the vehicle and other modes set to suppress the components constituting the sprung behavior of the vehicle body with a degree of suppression different from that of the fuel efficiency improvement mode. Calculate the force correction torque. Then, each of the calculated correction torques is added according to a weighting coefficient determined based on the traveling state of the vehicle, and a command value of the correction torque for the required braking / driving torque determined by the driver's braking / driving operation is calculated. As other modes, among the components constituting the sprung behavior of the vehicle body, a ride comfort improvement mode in which the degree of suppression of the pitch fluctuation component and the bounce component is set higher than the degree of suppression of the other components; A stability improvement mode that equalizes the degree of suppression of each component constituting the behavior, and the higher the vehicle speed in the ride comfort improvement mode and the stability improvement mode, the better the stability improvement mode. The weight is increased, and the weight of the riding comfort improvement mode is increased as the vehicle speed is lower.

According to the present invention, the braking / driving force control can be performed by changing the degree of emphasis between the fuel efficiency improvement performance and the other performance in accordance with the traveling state of the vehicle.
Therefore, it is possible to achieve both improvement in fuel consumption, steering stability and riding comfort performance.

It is a conceptual diagram showing the schematic structure of the vehicle of 1st Embodiment. It is a block diagram showing the functional composition of vehicles of a 1st embodiment. It is a block diagram showing the structure of the program which a microprocessor performs. 3 is a block diagram illustrating a configuration of a driving power wheel system vibration control unit 16. FIG. 3 is a flowchart showing the operation of a driving power wheel system vibration control unit 16. 3 is a block diagram illustrating a configuration of a suspension stroke calculation unit 21. FIG. 3 is a flowchart showing the operation of a suspension stroke calculation unit 21. It is a figure for demonstrating the calculation method of the stroke amount of a suspension. It is a graph showing a front-wheel suspension geometry characteristic. It is a graph showing a rear-wheel suspension geometry characteristic. 4 is a diagram for explaining a vehicle model 26. FIG. It is a figure which shows the map which defined the weighting coefficient of riding comfort improvement mode (B mode) and maneuverability improvement mode (C mode). It is a figure which shows the map which defined the weight coefficient of a fuel-consumption improvement mode (A mode), a ride comfort improvement mode, and the steering improvement mode (B mode and C mode). It is a figure which shows the vehicle model for demonstrating the effect | action of a fuel consumption improvement mode. It is a time chart which shows operation | movement of the braking / driving force control apparatus which concerns on 1st Embodiment. It is a figure which shows the map which defined the weighting coefficient of the riding comfort improvement mode (B mode) in the example of application, and the handling improvement mode (C mode). It is a figure which shows the map which defined the weighting coefficient of the riding comfort improvement mode (B mode) in the example 2 of application, and the operability improvement mode (C mode).

Next, an embodiment according to the present invention will be described with reference to the drawings.
(First embodiment)
The braking / driving force control device of this embodiment is mounted on a rear wheel drive type automobile and controls the sprung behavior of the vehicle body by controlling the torque generated by the engine as the power source. Specifically, the braking / driving force control device of the present embodiment is capable of suppressing wheel load fluctuations, improving steering responsiveness, suppressing roll behavior, and improving fuel consumption.

(Constitution)
FIG. 1 is a conceptual diagram illustrating a schematic configuration of a vehicle according to the first embodiment.
As shown in FIG. 1, the vehicle 1 includes a steering angle sensor 2, an accelerator opening sensor 3, a brake pedal depression force sensor 4, and a wheel speed sensor 5.
The steering angle sensor 2 is installed on the steering column and detects the steering angle δo by the steering wheel 6. Then, the steering angle sensor 2 outputs a detection signal indicating the detection result of the steering angle δo by the steering wheel 6 to an electronic control unit (hereinafter referred to as “ECU”) 12 described later.

The accelerator opening sensor 3 is disposed on the accelerator pedal and detects the accelerator opening. The accelerator opening is the amount of depression of the accelerator pedal. Then, the accelerator opening sensor 3 outputs a detection signal representing the detection result of the accelerator opening to the ECU 12.
The brake pedal depression force sensor 4 is installed on the brake pedal and detects the depression force of the brake pedal. Then, the brake pedal depression force sensor 4 outputs a detection signal indicating the detection result of the depression force of the brake pedal to the ECU 12.

The wheel speed sensor 5 is installed in each of the wheels 5FL to 5RR, and detects the wheel speed VwFL to VwRR of each of the wheels 5FL to 5RR. Then, the wheel speed sensor 5 outputs detection signals representing the wheel speeds VwFL to VwRR of the wheels 5FL to 5RR to the ECU 12.
The vehicle 1 also includes a differential gear 7, an engine 8, and a transmission 9.
The differential gear 7 is installed between the axle shafts 11 provided on the rear wheels (drive wheels) 5RL and 5RR, and the rotation of the engine 8 input via the output shaft of the transmission 9 is rotated. The difference is allowed and transmitted to the left and right rear wheels.

The engine 8 generates torque in response to a command input from the ECU 12. The engine 8 outputs the generated torque to the transmission 9 as rotation of the output shaft.
The transmission 9 converts the rotation of the output shaft of the engine 8 according to the gear ratio set by the driver through a shift operation, and outputs it to the rear wheels 5RL and 5RR via the drive shaft 10.
Further, the vehicle 1 includes an ECU 12.

  ECU12 consists of a microprocessor. The microprocessor includes an integrated circuit including an A / D conversion circuit, a D / A conversion circuit, a central processing unit, a memory, and the like. Then, the ECU 12 calculates the torque to be output to the engine 8 based on the detection signals output from the sensors 2 to 5 according to the program stored in the memory, and causes the engine 8 to output the calculated torque. Further, the ECU 12 applies braking force by the brake actuators 5BFL to 5BRR installed on the wheels 5FL to 5RR by controlling the brake fluid pressure based on the detection signal input from the brake pedal depression force sensor 4.

FIG. 2 is a block diagram illustrating a functional configuration of the vehicle according to the first embodiment.
As shown in FIG. 2, the vehicle 1 includes braking / driving torque applying means 100, behavior estimating means 101, correction torque calculating means 102, weight coefficient calculating means 103, and torque command value calculating means 104.
In FIG. 2, the braking / driving torque applying means 100 corresponds to the brake actuators 5BFL to 5BRR, the differential gear 7, the engine 8, and the transmission 9. Further, the behavior estimation unit 101, the correction torque calculation unit 102, the weight coefficient calculation unit 103, and the torque command value calculation unit 104 correspond to the ECU 12.

The braking / driving torque applying means 100 applies braking torque or driving torque to the wheel based on a correction torque command value calculated by a torque command value calculating means 104 described later.
The behavior estimation unit 101 estimates the sprung behavior of the vehicle body based on the traveling state of the vehicle. Then, the behavior estimation unit 101 outputs the estimation result of the sprung behavior of the vehicle body to the correction torque calculation unit 102.

  The correction torque calculation means 102 includes a fuel efficiency improvement mode in which the degree of suppression of the pitch fluctuation component is set higher than the degree of suppression of other components among the components constituting the sprung behavior of the vehicle body estimated by the behavior estimation means 101, and the vehicle body The vehicle travels based on other modes (for example, a ride comfort improvement mode and a maneuverability improvement mode, which will be described later) set so as to suppress components constituting the sprung behavior of the vehicle at a degree of suppression different from that of the fuel efficiency improvement mode. A correction torque of braking / driving force corresponding to the situation is calculated.

The weighting factor calculating means 103 calculates a weighting factor between the fuel efficiency improvement mode and other modes based on the running state of the vehicle (vehicle speed, pitch angular velocity, etc.).
The torque command value calculation means 104 calculates the final correction torque command value by multiplying the correction torque calculated by the correction torque calculation means 102 by the weight coefficient calculated by the weight coefficient calculation means 103 and adding the result. . Then, the torque command value calculating unit 104 outputs the calculated correction torque command value to the braking / driving torque applying unit 100.

FIG. 3 is a block diagram showing a configuration of a program executed by the microprocessor.
ECU12 comprises the control block of FIG. 3 with the program which a microprocessor performs. This control block includes a driver request torque calculation unit 13, an adder 14, a torque command value calculation unit 15, and a driving power vehicle system vibration control unit 16.
The driver request torque calculator 13 calculates the driver request torque based on the detection signal output from the accelerator opening sensor 3 and the detection signal output from the brake pedal depression force sensor 4. The driver request torque is an output torque requested by the driver from the engine 8. The driver request torque is represented by a motor end value that is a torque value on the rotation shaft of the engine 8. Then, the driver request torque calculation unit 13 outputs the calculated driver request torque to the adder 14 and the driving power vehicle system vibration control unit 16.

  In the present embodiment, an example in which the driver request torque is calculated based on the detection signal output from the accelerator opening sensor 3 and the detection signal output from the brake pedal depression force sensor 4 has been described, but other configurations are employed. You can also. For example, it is good also as a structure which makes the detected value itself by various sensors, such as the accelerator opening sensor 3, etc. into a driver request | requirement torque.

The adder 14 adds the driver torque correction value output from the driving force vehicle system vibration control unit 16 to the driver request torque output from the driver request torque calculation unit 13. As a result, the driver request torque is corrected. The driver torque correction value is a correction value calculated by the driving force vehicle system vibration control unit 16 based on the driver request torque, the wheel speeds VwFL to VwRR, the engine speed, and the steering angle δo as described later. Then, the driver request torque calculation unit 13 outputs the corrected driver request torque to the torque command value calculation unit 15 as the corrected request torque.
The torque command value calculation unit 15 is a torque to be output to the engine 8 based on the corrected required torque output from the adder 14 and the output of another system such as VDC (Vehicle Dynamics Control) or TCS (Traction Control System). Is calculated. Then, the torque command value calculation unit 15 outputs the calculated torque to the engine 8 as a command value.

FIG. 4 is a block diagram illustrating the configuration of the driving power wheel system vibration control unit 16.
FIG. 5 is a flowchart showing the operation of the driving power wheel system vibration control unit 16.
As shown in FIG. 4, the driving power vehicle vibration control unit 16 includes an input conversion unit 17, a vehicle body vibration estimation unit 18, a torque command value calculation unit 19, and a mode weight coefficient calculation unit 16 </ b> A.
The input conversion unit 17 uses the information represented by the detection signals output from the steering angle sensor 2, the accelerator opening sensor 3, the brake pedal depression force sensor 4, and the wheel speed sensor 5 as the input format of the vehicle model 26 used in the vehicle body vibration estimation unit 18. Convert to Specifically, the input conversion unit 17 includes a drive torque conversion unit 20, a suspension stroke calculation unit 21, a vertical force conversion unit 22, a vehicle body speed estimation unit 23, a turning behavior estimation unit 24, and a turning resistance estimation unit 25.

  The drive torque converter 20 reads the driver request torque output by the driver request torque calculator 13 (step S101 in FIG. 5). Subsequently, the drive torque converter 20 multiplies the read driver request torque by the gear ratio of the transmission 9. Thus, the driver request torque is converted from the motor end value to the drive shaft end value (step S102 in FIG. 5). Here, the drive shaft end value is a torque value in the rear wheels 5RL and 5RR. Then, the drive torque conversion unit 20 outputs the multiplication result as the drive torque Tw to the vehicle body vibration estimation unit 18. Here, the drive torque Tw is the drive shaft end value of the driver request torque.

FIG. 6 is a block diagram showing the configuration of the suspension stroke calculation unit 21.
FIG. 7 is a flowchart showing the operation of the suspension stroke calculation unit 21.
The suspension stroke calculation unit 21, based on the detection signal output from the wheel speed sensor 5, that is, the detection signal indicating the wheel speed VwFL to VwRR, the suspension stroke amounts Zf and Zr and the stroke speed dZf of the front and rear wheels 5FL to 5RR, dZr is calculated. Specifically, as shown in FIG. 6, the suspension stroke calculation unit 21 includes an average front wheel speed calculation unit 37, an average rear wheel speed calculation unit 38, a front wheel band pass filter processing unit 39, and a rear wheel band pass filter process. Unit 40, front wheel suspension stroke calculation unit 41, and rear wheel suspension stroke calculation unit 42.

  The average front wheel speed calculation unit 37 reads the detection signals output from the wheel speed sensors 5 of the front wheels 5FL and 5FR (step S103 in FIG. 5 and step S201 in FIG. 7). Subsequently, the average front wheel speed calculation unit 37 calculates the average front wheel speed VwF = (VwFL + VwFR) / 2 based on the read detection signal (step S202 in FIG. 7). The average front wheel speed calculation unit 37 then outputs the calculated average front wheel speed VwF to the front wheel band-pass filter processing unit 39.

  The average rear wheel speed calculation unit 38 reads the detection signals output from the wheel speed sensors 5 of the rear wheels 5RL and 5RR (step S103 in FIG. 5 and step S201 in FIG. 7). Subsequently, the average rear wheel speed calculation unit 38 calculates an average rear wheel speed VwR = (VwRL + VwRR) / 2 based on the read rear wheel speeds VwRL and VwRR (step S202 in FIG. 7). Then, the average rear wheel speed calculation unit 38 outputs the calculated average rear wheel speed VwR to the rear wheel band pass filter processing unit 40.

  The front wheel band pass filter processing unit 39 extracts only components near the vehicle body resonance frequency from the average front wheel speed VwF output by the average front wheel speed calculation unit 37. Then, the front wheel band pass filter processing unit 39 outputs the extracted vehicle body resonance frequency vicinity vibration component fVwF to the front wheel suspension stroke calculation unit 41 and the rear wheel suspension stroke calculation unit 42 (step S203 in FIG. 7).

The rear wheel band pass filter processing unit 40 extracts only components near the vehicle body resonance frequency from the average rear wheel speed VwR output by the average rear wheel speed calculation unit 38. Then, the rear wheel band pass filter processing unit 40 outputs the extracted vehicle body resonance frequency vicinity vibration component fVwR to the front wheel suspension stroke calculation unit 41 and the rear wheel suspension stroke calculation unit 42 (step S203 in FIG. 7).
Thus, in this embodiment, only the components fVwF and fVwR in the vicinity of the vehicle body resonance frequency are extracted from the average front wheel speed VwF and the average rear wheel speed VwR. Therefore, wheel speed fluctuations and noise components due to acceleration / deceleration of the entire vehicle 1 can be removed from the average front wheel speed VwF and the average rear wheel speed VwR, and only the wheel speed component representing vehicle body vibration can be extracted.

FIG. 8 is a diagram for explaining a method of calculating the stroke amount of the suspension.
FIG. 9 is a graph showing the front wheel suspension geometry characteristics.
FIG. 10 is a graph showing the rear wheel suspension geometry characteristics.
The front wheel suspension stroke calculation unit 41 calculates the longitudinal displacement Xtf of the front wheels 5FL and 5FR based on the vehicle body resonance frequency vicinity vibration component fVwF extracted by the front wheel bandpass filter processing unit 39. Subsequently, the front wheel suspension stroke calculation unit 41 calculates a time differential value dXtf by performing time differentiation on the calculated longitudinal displacement Xtf. Subsequently, the front wheel suspension stroke calculation unit 41 calculates the suspension stroke amount Zf and the stroke speed dZf according to the following equations (1) and (2) based on the calculated longitudinal displacement Xtf and time differential value dXtf. Then, the front wheel suspension stroke calculation unit 41 outputs the calculation result to the vertical force conversion unit 22.

Zf = KgeoF · Xtf (1)
dZf = KgeoF ・ dXtf (2)
Here, KgeoF is the gradient near the origin of the graph representing the front wheel suspension geometry characteristic of FIG. In the graph of FIG. 9, the horizontal axis represents the longitudinal displacement Xtf of the front wheels 5FL, 5FR, the vertical axis represents the vertical displacement Zf of the vehicle body above the front wheels 5FL, 5FR, the longitudinal displacement Xtf, and the vertical displacement Zf of the vehicle body. It is a graph showing the relationship.

  The rear wheel suspension stroke calculation unit 42 calculates the longitudinal displacement Xtr of the rear wheels 5RL and 5RR based on the vehicle body resonance frequency vicinity vibration component fVwR extracted by the rear wheel bandpass filter processing unit 40. Subsequently, the rear wheel suspension stroke calculation unit 42 performs time differentiation on the calculated longitudinal displacement Xtr to calculate a time differentiation value dXtr. Subsequently, the rear wheel suspension stroke calculation unit 42 calculates the suspension stroke amount Zr and the stroke speed dZr according to the following equations (3) and (4) based on the calculated longitudinal displacement Xtr and time differential value dXtr. Then, the front wheel suspension stroke calculation unit 41 outputs the calculation result to the vertical force conversion unit 22.

Zr = KgeoR ・ Xtr (3)
dZr = KgeoR ・ dXtr (4)
Here, KgeoR is the gradient near the origin of the graph representing the rear wheel suspension geometry characteristics of FIG. In the graph of FIG. 10, the horizontal axis represents the longitudinal displacement Xtr of the rear wheels 5RL, 5RR, the vertical axis represents the vertical displacement Zr of the vehicle body above the rear wheels 5RL, 5RR, and the longitudinal displacement Xtr and the vertical displacement of the vehicle body. It is a graph showing the relationship with Zr.

  Returning to FIG. 4, the vertical force conversion unit 22 multiplies the stroke amount Zf output from the suspension stroke calculation unit 21 by the spring constant Kf, and multiplies the stroke speed dZf output from the suspension stroke calculation unit 21 by the damping coefficient Cf. . Here, the spring constant Kf is a spring constant of the suspension of the front wheels 5FL and 5FR. The damping coefficient Cf is a damping coefficient of the suspension (shock absorber) of the front wheels 5RL and 5FR. Then, the vertical force conversion unit 22 outputs the sum of these multiplication results to the vehicle body vibration estimation unit 18 as the vertical force Fzf of the front wheels 5FL, 5FR (step S105 in FIG. 5). Here, the vertical force is an external force applied to the vehicle body by road surface disturbance applied to the wheels 5FL to 5RR from the road surface.

  The vertical force conversion unit 22 multiplies the stroke amount Zr output from the suspension stroke calculation unit 21 by the spring constant Kr, and also multiplies the stroke speed dZr output from the suspension stroke calculation unit 21 by the damping coefficient Cr. Here, the spring constant Kr is a spring constant of the suspension of the rear wheels 5RL and 5RR. The damping coefficient Cr is a damping coefficient of the suspension (shock absorber) of the rear wheels 5RL and 5RR. Then, the vertical force conversion unit 22 outputs the sum of these multiplication results to the vehicle body vibration estimation unit 18 as the vertical force Fzr of the rear wheels 5RL and 5RR (step S105 in FIG. 5).

  In the present embodiment, the suspension stroke amount and stroke speed are calculated based on the wheel speeds VWFL to VWRR, and the vertical forces Fzf and Fzr are calculated based on the calculated stroke amount and stroke speed. Other configurations can also be employed. For example, a stroke sensor that detects the stroke amount of the suspension may be provided, and the vertical forces Fzf and Fzr may be calculated based on the stroke amount detected by the stroke sensor and the time differential value of the detection result. Moreover, it is good also as a structure which uses the detection value itself by various sensors, such as a stroke sensor, as the vertical forces Fzf and Fzr.

The vehicle body speed estimation unit 23 reads the detection signals output from the wheel speed sensors 5 of the front wheels 5FL and 5FR (driven wheels). Subsequently, the average rear wheel speed calculation unit 38 calculates the vehicle body speed V = (VwRL + VwRR) / 2 based on the read detection signal. Then, the vehicle body speed estimation unit 23 outputs the calculated vehicle body speed V to the turning behavior estimation unit 24.
The turning behavior estimation unit 24 calculates the yaw angular velocity γ and the vehicle slip angle βv according to the following equations (5) and (6) based on the detection signal output by the vehicle body speed estimation unit 23 and the detection signal output by the steering angle sensor 2. To do. Then, the turning behavior estimation unit 24 outputs the calculated yaw angular velocity γ and the vehicle body side slip angle βv to the turning resistance estimation unit 25. The turning behavior estimation unit 24 also outputs the steering angle δo represented by the detection signal of the steering angle sensor 2 together with these calculation results.

  Where V is the vehicle speed, δ is the tire turning angle calculated based on the steering angle δo, l is the wheelbase, lf is the distance from the center of gravity of the vehicle body to the front axle, lr is the distance from the center of gravity of the vehicle body to the rear axle, m is the vehicle weight. Cpf is the tire cornering power of the front wheels 5FL and 5FR, and Cpr is the tire cornering power of the rear wheels 5RL and 5RR.

  The turning resistance estimation unit 25 calculates the turning resistance Fcf of the front wheels 5FL and 5FR according to the following equation (7) based on the yaw angular velocity γ, the vehicle body side slip angle βv, and the steering angle δo output by the turning behavior estimation unit 24. Here, the turning resistance Fcf is a resistance applied to the wheels 5FL to 5RR from the road surface by steering, and is a vehicle longitudinal component of a lateral force applied to the wheels 5FL to 5RR due to the occurrence of a slip angle. Then, the turning resistance estimation unit 25 outputs the calculated turning resistance Fcf to the vehicle model 26.

Fcf = βf ・ Fyf (7)
βf = βv + Lf · γ / V−δ
Fyf = βf · Cpf
Here, δ is the tire turning angle calculated based on the steering angle δo, and Lf is the distance from the center of gravity of the vehicle body to the front axle. Cpf is the tire cornering power of the front wheels 5FL and 5FR, βf is the slip angle of the front wheels 5FL and 5FR, and Fyf is the cornering force of the front wheels 5FL and 5FR.

Further, the turning resistance estimation unit 25 calculates the turning resistance Fcr of the rear wheels 5RL and 5RR according to the following equation (8) based on the yaw angular velocity γ, the vehicle body side slip angle βv, and the steering angle δo output by the turning behavior estimation unit 24. calculate. Then, the turning resistance estimation unit 25 outputs the calculated turning resistance Fcr to the vehicle model 26.
Fcr = βr · Fyr (8)
βr = βv−Lr ・ γ / V
Fyr = βr · Cpr
Here, δ is a tire turning angle calculated based on the steering angle δo, and Lr is a distance from the center of gravity of the vehicle body to the rear axle. Cpr is the tire cornering power of the rear wheels 5RL and 5RR, βr is the slip angle of the rear wheels 5FL and 5FR, and Fyr is the cornering force of the rear wheels 5FL and 5FR.

In the present embodiment, the example in which the turning resistances Fcf and Fcr are calculated based on the vehicle body speed V and the steering angle δo has been shown, but other configurations may be employed. For example, the detection values themselves by various sensors such as the steering angle sensor 2 may be used as the turning resistances Fcf and Fcr.
The vehicle body vibration estimation unit 18 calculates components constituting the sprung behavior of the vehicle body based on the drive torque Tw, the vertical forces Fzf and Fzr, and the turning resistances Fcf and Fcr output from the input conversion unit 17. Specifically, the vehicle body vibration estimation unit 18 includes a vehicle model 26.

FIG. 11 is a diagram for explaining the vehicle model 26.
The vehicle model 26 calculates a component caused by the driving torque Tw, a component caused by the vertical forces Fzf and Fzr, and a component caused by the turning resistances Fcf and Fcr among components constituting the sprung behavior of the vehicle body. That is, the sprung behavior of the vehicle body can be expressed by various physical quantities, and each of these various physical quantities includes various components, and the vehicle model 26 includes the above-described 3 of the various components. One component is calculated separately. Here, as the sprung behavior of the vehicle body, rotational motion around the pitch axis of the vehicle body and vertical motion in the bounce direction can be employed. As physical quantities representing the sprung behavior of the vehicle body, the bounce speed dZv, the bounce amount Zv, the pitch angular velocity dθp, and the pitch angle θp of the vehicle body can be adopted. These physical quantities dZv, Zv, dθp, and θp are parameters necessary for defining the front wheel load Wf and the rear wheel load Wr, as shown in the following equations (9) and (10).

Wf = −2Kf (Zv + Lf · θp) −2Cf (dZv + Lf · dθp / dt) (9)
Wr = −2Kr (Zv + Lr · θp) −2Cr (dZv−Lr · dθp / dt) (10)
Here, Kf is a spring constant of the suspension of the front wheels 5FL and 5FR, and Cf is a damping coefficient of the suspension (shock absorber) of the front wheels 5RL and 5FR. Kr is a spring constant of the suspension of the rear wheels 5RL and 5RR, and Cr is a damping coefficient of the suspension (shock absorber) of the rear wheels 5RL and 5RR. Lf is the distance from the center of gravity of the vehicle body to the front axle, Lr is the distance from the center of gravity of the vehicle body to the rear axle, and θp is the pitch angle of the vehicle body.

  Specifically, the vehicle model 26 is based on the drive torque Tw output from the drive torque conversion unit 20, and among the components constituting the sprung behavior of the vehicle body, the components caused by the drive torque Tw (the bounce speed and bounce of the vehicle body). Quantity, pitch angular velocity, pitch angle). The calculation of the component due to the drive torque Tw is performed according to the following equations (11) and (12) with Fzf, Fzr, Fcf, and Fcr set to “0” (step S112 in FIG. 5). The vehicle model 26 outputs the calculated component to the torque command value calculation unit 19. In the following equation, the differential value is represented by a doted code.

Here, as shown in FIG. 11, Ip is the moment of inertia around the pitch axis, hcg is the height of the center of gravity of the vehicle body, Rt is the height of the center of gravity of the wheel, and θp is the pitch angle. Also, zv is the vertical movement of the center of gravity position, Ff and Fr are the vertical force of the vehicle on the front and rear wheels, Rt is the height of the wheel center of gravity, Tw is the driving torque, and M is the mass on the spring.
Further, the vehicle model 26 is based on the vertical forces Fzf and Fzr output from the vertical force converter 22 and among the components constituting the sprung behavior of the vehicle body, components caused by the vertical forces Fzf and Fzr (the bounce speed of the vehicle body, Bounce amount, pitch angular velocity, pitch angle). The calculation of the components caused by the vertical forces Fzf and Fzr is performed according to the above equations (11) and (12) with Tw, Fcf and Fcr being “0” (step S112 in FIG. 5). The vehicle model 26 outputs the calculated component to the torque command value calculation unit 19.

  In the present embodiment, an example is shown in which the component caused by the driving torque Tw and the components caused by the vertical forces Fzf and Fzr are calculated from the components constituting the sprung behavior of the vehicle body. Can also be adopted. For example, at least one of the bounce speed, the bounce amount, the pitch angular speed, and the pitch angle of the vehicle body, or a component that constitutes a composite value thereof, a component caused by the driving torque Tw, and a vertical force Fzf, Fzr It is good also as a structure which calculates the component to perform. As the composite value, for example, a value obtained by multiplying each of the bounce speed, the bounce amount, the pitch angular speed, and the pitch angle of the vehicle body by a coefficient and summing the multiplication results can be employed.

  Further, the vehicle model 26 is based on the turning resistances Fcf and Fcr output from the turning resistance estimation unit 25, and among the components constituting the sprung behavior of the vehicle body, the components caused by the vertical forces Fzf and Fzr (the bounce speed of the vehicle body, Bounce amount, pitch angular velocity, pitch angle). Calculation of the components due to the turning resistances Fcf and Fcr is performed according to the above equations (11) and (12) with Tw, Fzf, and Fzr being “0” (step S112 in FIG. 5). Subsequently, the vehicle model 26 calculates components dWf, dWr, dSF, SF due to the turning resistances Fcf, Fcr among the components constituting the sprung behavior of the vehicle body based on the calculated components. However, dWf is the fluctuation speed of the front wheel load, dWr is the fluctuation speed of the rear wheel load, dSF is the fluctuation speed of the front-rear balance, and the SF front-back balance. Calculation of the components dWf, dWr, dSF, SF due to the turning resistances Fcf, Fcr is performed according to the above equations (9) and (10) (step S112 in FIG. 5). The vehicle model 26 then outputs the calculated components dWf, dWr, dSF, SF to the torque command value calculation unit 19.

  In the present embodiment, an example is shown in which components due to the turning resistances Fcf and Fcr are calculated from among the components constituting the sprung behavior of the vehicle body, but other configurations may be employed. For example, at least one of the front wheel load, the front wheel load fluctuation speed, the pitch angular speed, and the pitch angle, or a component that forms a composite value thereof, a component caused by the turning resistance Fcf, Fcr, and a vertical force Fzf, It is good also as a structure which calculates the component resulting from Fzr. As the composite value, for example, a value obtained by multiplying each of the front wheel load, the fluctuation speed of the front wheel load, the pitch angular speed, and the pitch angle by a coefficient and totaling the multiplication results can be employed.

  In the mode weight coefficient calculation unit 16A, based on the vehicle body speed V and the pitch angular speed of the vehicle, the fuel efficiency improvement mode (hereinafter referred to as “A mode”) and the ride comfort improvement mode (hereinafter referred to as “B mode” as appropriate). ), The respective weighting factors of the operability improvement mode (hereinafter referred to as “C mode” as appropriate) are calculated (step S113 in FIG. 5). Here, the total pitch angular speed calculated by the vehicle model 26 is used as the pitch angular speed of the vehicle. As the vehicle body speed V, the vehicle body speed V calculated by the vehicle body speed estimation unit 23 is used.

  Here, the fuel efficiency improvement mode (A mode) is a mode in which fuel consumption is improved by giving priority to suppression of pitch fluctuation among vertical behaviors (pitch, bounce, front / rear axis balance and wheel load fluctuation) generated in the vehicle body. It is. The riding comfort improvement mode (B mode) is a mode for improving the riding comfort by giving priority to the suppression of pitch fluctuation and bounce among the vertical behaviors generated in the vehicle body. Stability improvement mode improves handling by promoting fluctuations in wheel load without giving priority to suppression of fluctuations in pitch, bounce, and front / rear axis balance among the vertical movements that occur in the vehicle body. It is a mode to make it.

FIG. 12 is a diagram showing a map in which weighting factors for the ride comfort improvement mode (B mode) and the operability improvement mode (C mode) are determined.
In FIG. 12, the weighting factors of the riding comfort improvement mode and the maneuverability improvement mode are respectively calculated from the vehicle speed.
For example, at point x1 in FIG. 12, the vehicle speed is medium speed, and both the B mode and C mode weights are 0.5.

FIG. 13 is a diagram showing a map that defines weighting factors for the fuel efficiency improvement mode (A mode) and the ride comfort improvement mode and the maneuverability improvement mode (B mode and C mode).
In FIG. 13, from the pitch angular velocity, the weighting factors for the riding comfort improvement mode and the handling improvement mode calculated according to FIG. 12 and the weighting factors for the fuel consumption improvement mode are calculated.
For example, at point x2 in FIG. 13, the pitch angular velocity is medium, and the A mode weight coefficient and the B mode and C mode weight coefficients are both 0.5. Therefore, when the state of the vehicle 1 is the point x1 in FIG. 12 and the point x2 in FIG. 13, the weighting coefficient in the A mode is 0.5, and the weighting coefficient in the B mode and the C mode is 0.25 (0.5 × 0.5).

If the pitch angular velocity is used as it is for the calculation of the weighting factor, the pitch angular velocity of the vehicle body changes periodically, so that the weighting factor also changes in accordance with the vibration cycle. Therefore, when the pitch angular velocity amplitude is used for calculating the weighting factor using the pitch angular velocity peak-to-peak (envelope), the weighting factor can be calculated more appropriately.
Here, the operation of the fuel efficiency improvement mode will be described.
FIG. 14 is a diagram illustrating a vehicle model for explaining the operation of the fuel efficiency improvement mode.
In FIG. 14, the speed of the vehicle body is as shown in the following equation.

Here, m ₁ is the unsprung mass, M is the sprung mass, Rt is the height of the wheel center of gravity, I is the inertia moment of rotation of the wheel, and Tw is the braking / driving torque. Other reference numerals are the same as those in FIG.
From this, it can be seen that the speed of the vehicle body is proportional to the integral of the braking / driving torque inputted.
On the other hand, the energy E of the vehicle body can be calculated by multiplying the input torque T and the relative angular velocity (difference between the rotational angular velocity of the wheel and the rotational angular velocity of the vehicle body) as shown in the following equation.

In equation (14), θ _T is the wheel rotation angle, and θp is the vehicle body pitch angle.
That is, when the vehicle speed is the same, it can be understood that the smaller the relative angular velocity, the smaller the energy.
For this reason, energy efficiency can be improved by giving torque in the situation where relative angular velocity is small. This corresponds to applying torque to the phase opposite to the pitch angular velocity of the vehicle body.

Due to the above-described action, the fuel efficiency improvement effect is enhanced where the pitch angular velocity is large.
Therefore, in the present invention, in a situation where the pitch angular velocity is large, the pitch suppression gain is increased with respect to the bounce suppression and the front load gain so as to improve fuel efficiency. In a situation where the pitch angular velocity is small, the gain is changed so as to improve the riding comfort performance and the steering performance of the vehicle.

On the other hand, in a region where the pitch angular velocity is low and the vehicle speed is low, although not the maximum, it is possible to expect a fuel efficiency improvement effect. Therefore, the gain of pitch suppression and bounce suppression is increased with respect to the front load gain, thereby improving riding comfort performance.
In general, in a region where the vehicle speed is high, the energy consumption is large in the first place, and the fuel efficiency effect is reduced. For this reason, in the region where the pitch angular velocity is low and the vehicle speed is high, the fuel efficiency improvement effect is the smallest, so that the steering performance is improved by outputting all gains equally.

  Returning to FIG. 4, the torque command value calculation unit 19 performs a regulator process on each state quantity to be controlled based on the components constituting the sprung behavior of the vehicle body output from the vehicle body vibration estimation unit 18. Further, the torque command value calculation unit 19 multiplies the result of the regulator process by a gain set and a weighting factor for each of the A to C modes. Then, the torque command value calculation unit 19 converts the sum of these multiplication values into an engine end value of torque corresponding to the gear ratio, and outputs it.

  The state quantities to be controlled in the torque command value calculation unit 19 are “pitch speed by driving torque”, “bounce speed by driving torque”, “pitch speed by disturbance (estimated from wheel speed)”, “disturbance (wheel Bounce speed due to speed (estimated from speed) "," front and rear axis balance fluctuation due to disturbance (estimated from wheel speed) "," front and rear axis balance due to disturbance (estimated from wheel speed) "," front wheel load due to turning resistance " Fluctuation ”and“ Rear wheel load fluctuation due to turning resistance ”.

Then, the torque command value calculation unit 19 and regulator gains F1 to F5 set for these eight state quantities and tuning gains K1a to K8a, K1b to K8b, K1c to K8c (hereinafter referred to as A to C) corresponding to the A to C modes. A set of tuning gains for each of the C modes is appropriately referred to as “gain set”).
Specifically, the torque command value calculation unit 19 includes a first regulator 27, a second regulator 28, a third regulator 29, a first tuning gain setting unit 30, a second tuning gain setting unit 31, and a third tuning gain setting unit. 32, a first tuning gain multiplication unit 33, a second tuning gain multiplication unit 34, a third tuning gain multiplication unit 35, and an engine torque conversion unit 36.

The first regulator 27 receives the pitch speed based on the driving torque output from the vehicle model 26 and the bounce speed based on the driving torque, and multiplies the input values by the regulator gains F1 and F2 corresponding to these, and the regulator processing result R1. , R2 is calculated.
The second regulator 28 depends on the pitch speed due to the disturbance (estimated from the wheel speed) output by the vehicle model 26, the bounce speed due to the disturbance (estimated from the wheel speed), and the disturbance (estimated from the wheel speed). The front-rear axis balance fluctuation and the front-rear axis balance due to disturbance (estimated from the wheel speed) are input, and the regulator gains F3-F6 corresponding to these are multiplied by the input values to calculate the regulator processing results R3-R6. .

The third regulator 29 receives the front wheel load fluctuation caused by the turning resistance output from the vehicle model 26 and the rear wheel load fluctuation caused by the turning resistance, and multiplies the input values by regulator gains F7 and F8 corresponding to these fluctuations. Processing results R7 and R8 are calculated.
The first tuning gain setting unit 30 sets the tuning gain for the regulator processing results R1 and R2 output from the first regulator 27. Specifically, the first tuning gain setting unit 30 performs A mode gain (1/2, 0), B mode gain (1/4, 1/4), C mode gain (1) for the regulator processing results R1, R2. / 8, 1/8) is set. When the first tuning gain setting unit 30 sets a positive tuning gain, the pitch fluctuation and bounce are suppressed.

  The second tuning gain setting unit 31 sets a tuning gain for the regulator processing results R3 to R6 output from the second regulator 28. Specifically, the second tuning gain setting unit 31 includes an A mode gain (1/2, 0, 0, 0) and a B mode gain (1/4, 1/4, 0, 0), C mode gain (1/8, 1/8, 1/8, 1/8) is set. In addition, when the second tuning gain setting unit 30 sets a positive tuning gain, control for suppressing pitch fluctuation, bounce, front-back axis balance fluctuation, and front-back axis balance difference (difference from a reference state such as when stationary). It becomes.

  The third tuning gain setting unit 32 sets a tuning gain for the regulator processing results R7 and R8 output from the third regulator 29. Specifically, the third tuning gain setting unit 32 performs A mode gain (0, 0), B mode gain (0, 0), C mode gain (1/8, 1/8) for the regulator processing results R7, R8. ) Is set. Note that when the third tuning gain setting unit 32 sets a negative tuning gain, control is performed to promote fluctuations in wheel load.

The gain set for the A to C mode is determined by the tuning gain set by the first tuning gain setting unit 30 to the third tuning gain setting unit 32.
The first tuning gain multiplication unit 33 multiplies the regulator processing results R1 to R8 output by the regulators with the tuning gains of the A mode gain set, and calculates multiplication results RA1 to RA8. Further, the first tuning gain multiplication unit 33 multiplies each of the A mode weighting coefficients output from the mode weighting coefficient calculation unit 16A by the tuning gain multiplication results RA1 to RA8 to calculate A mode torque command values TA1 to TA8. (Step S114 in FIG. 5).

  The second tuning gain multiplier 34 multiplies the regulator processing results R1 to R8 output by the regulators with the tuning gains of the B mode gain set, and calculates multiplication results RB1 to RB8. Further, the second tuning gain multiplication unit 34 multiplies each of the B mode weight coefficients output from the mode weight coefficient calculation unit 16A by the tuning gain multiplication results RB1 to RB8, and calculates B mode torque command values TB1 to TB8. (Step S115 in FIG. 5).

  The third tuning gain multiplication unit 35 multiplies the regulator processing results R1 to R8 output from each regulator by each tuning gain of the C mode gain set, and calculates multiplication results RC1 to RC8. Further, the third tuning gain multiplication unit 35 multiplies each of the C mode weighting coefficients output from the mode weighting coefficient calculation unit 16A by the tuning gain multiplication results RC1 to RC8 to calculate C mode torque command values TC1 to TC8. (Step S116 in FIG. 5).

  The engine torque conversion unit 36 adds up the A mode torque command values TA1 to TA8, the B mode torque command values TA1 to TB8, and the C mode torque command values TC1 to TC8 (step S117 in FIG. 5), and adds the transmission to the total value. 9 is multiplied (step S118 in FIG. 5). As a result, the engine torque converter 36 converts the total value from the drive shaft end value to the motor end value. The engine torque conversion unit 36 outputs the multiplication result to the adder 14 as a torque correction value.

  When the value obtained by adding the regulator gain to each state quantity in the first to third regulators is subtracted from the driving torque of the vehicle, each state quantity converges in an equilibrium state (that is, the direction in which vibration stops here). Specifically, a value obtained by adding a negative regulator gain to each state quantity is used as a correction torque, and this is added to the drive torque, so that each state quantity is in an equilibrium state.

However, since the driving torque is changed, if the driving torque command value is used as it is, the fluctuation in the longitudinal acceleration may give the driver a sense of incongruity, and control for improving the target steering response and suppressing the roll behavior. It becomes difficult to realize. Therefore, the tuning gains K1a to K6a, K1b to K6b, and K1c to K6c are values in a positive direction that suppress vibrations, and values in a range that can be estimated that fluctuations in longitudinal acceleration do not give the driver a sense of incongruity (for example, experimental values) ). On the other hand, the tuning gains K7a, K8a, K7b, K8b, K7c, and K8c are set to values in a negative direction that promotes vibration and in a range in which fluctuations in longitudinal acceleration do not give the driver a sense of incongruity.
In addition, after step S118, the driving power wheel system vibration control unit 16 repeats the process of FIG.

(Operation)
Next, the operation will be described.
FIG. 15 is a time chart showing the operation of the braking / driving force control apparatus according to the first embodiment.
FIG. 15 shows a time chart of the pitch angular velocity of the vehicle body 1B, the peak to peak value of the pitch angular velocity, the wheel rotation angular velocity, the A mode weighting factor, the B mode weighting factor, and the C mode weighting factor.
First, while traveling on a highway, in order for the driver to travel straight ahead at a constant speed, the driver keeps the accelerator opening constant and holds the steering wheel 6 at the origin position, as shown at time t0 in FIG. Suppose that the steering input is set to “0”. Then, as shown in FIG. 3, the driver request torque calculator 13 of the ECU 12 calculates the driver request torque based on the detection signal output from the accelerator opening sensor 3 and the detection signal output from the brake pedal depression force sensor 4. . Then, the driver request torque calculation unit 13 outputs the calculated driver request torque to the adder 14 and the input conversion unit 17. When the driver request torque calculation unit 13 outputs the driver request torque, as shown in FIG. 4, the drive torque conversion unit 20 of the input conversion unit 17 multiplies the driver request torque by the gear ratio of the transmission 9, and the multiplication result is obtained. The driving torque Tw is output to the vehicle model 26.

When the drive torque converter 20 outputs the drive torque Tw, the engine 8 outputs torque, and a force for pitching the vehicle body works.
In the present embodiment, weighting between the B mode (riding comfort improvement mode) and the C mode (stability improvement mode) is determined according to the vehicle speed. Then, the A mode (fuel efficiency improvement mode) is weighted with respect to the total weight of the B mode and the C mode.

  For example, in FIG. 15, at time t0, the pitching amount and the vehicle speed are both small. At this time, since the vehicle speed is low, emphasis is placed on improving riding comfort, and the weighting between the B mode and the C mode is 1: 0 (see FIG. 12). Further, the weight of the A mode is 0 with respect to the weight of the B mode and the C mode (see FIG. 13). As a result, the weight of the B mode is 1 at time t0.

  In FIG. 15, the pitching amount increases to a medium level at time t1. At this time, since the vehicle speed is low, emphasis is placed on improving riding comfort, and the weighting between the B mode and the C mode is 1: 0 (see FIG. 12). Further, the weight of the A mode is ½ of the weight of the B mode and the C mode (see FIG. 13). As a result, at the time t1, the weight of the A mode and the B mode is 0.5: 0.5. It becomes.

  In FIG. 15, the pitching amount increases to a large extent at time t2. At this time, since the vehicle speed is low, priority is given to improving the ride comfort, and the weighting between the B mode and the C mode is 1: 0 (see FIG. 12). Further, the weight of the A mode is 1 with respect to the weight of the B mode and the C mode (see FIG. 13). As a result, the weight of the A mode is 1 at time t2.

  In FIG. 15, at time t3, the pitching amount decreases to a medium level and the vehicle speed increases to a high speed. At this time, since the vehicle speed is high, emphasis is placed on improving maneuverability, and the weighting between the B mode and the C mode is 0: 1 (see FIG. 12). Further, the weight of the A mode is ½ of the weight of the B mode and the C mode (see FIG. 13). As a result, at the time t3, the weight of the A mode and the C mode is 0.5: 0.5. It becomes.

  In FIG. 15, at time t4, the pitching amount decreases to a small state. At this time, since the vehicle speed is high, emphasis is placed on improving maneuverability, and the weighting between the B mode and the C mode is 0: 1 (see FIG. 12). Further, the weight of the A mode is 0 with respect to the weight of the B mode and the C mode (FIG. 13). As a result, the weight of the C mode is 1 at time t4.

As described above, the vehicle 1 including the braking / driving force control device according to the present embodiment includes a mode for performing braking / driving force control for improving fuel efficiency, and a mode for performing braking / driving force control for improving riding comfort. And a mode for performing braking / driving force control for improving the maneuverability.
Then, the vehicle 1 sets the weight of the ride comfort improvement mode and the maneuverability improvement mode according to the vehicle speed, and sets the weight of the fuel consumption improvement mode according to the pitching amount of the vehicle body.

Therefore, the braking / driving force control can be performed by changing the degree of emphasis on the operability and the ride comfort and the improvement of the fuel consumption according to the traveling state of the vehicle.
Therefore, it is possible to achieve both improvement in fuel consumption, steering stability and riding comfort performance.
Further, in the vehicle 1 according to the present embodiment, when the weighting of each mode is set, the fuel consumption improvement mode is set to twice the weight ratio with respect to the two modes of the ride comfort improvement mode and the maneuverability improvement mode. .

Therefore, it is possible to preferentially improve fuel efficiency in various driving situations.
In this embodiment, the brake actuators 5BFL to 5BRR, the differential gear 7, the engine 8, and the transmission 9 correspond to braking / driving torque applying means, and the ECU 12 (the input conversion unit 17, the vehicle body vibration estimation unit 18) estimates the behavior. Corresponds to the means. The ECU 12 (torque command value calculation unit 19) corresponds to the correction torque calculation unit, and the ECU 12 (mode weight coefficient calculation unit 16A) corresponds to the weight coefficient calculation unit. Moreover, ECU12 (engine torque conversion part 36) respond | corresponds to a torque command value calculation means.

(Effect of 1st Embodiment)
(1) Among the components constituting the estimated sprung behavior of the vehicle body, the fuel consumption improvement mode in which the degree of suppression of the pitch fluctuation component is set higher than the degree of suppression of other components, and the components constituting the sprung behavior of the vehicle body A braking / driving force correction torque corresponding to the traveling state of the vehicle is calculated on the basis of the fuel efficiency improvement mode and another mode that is set to be suppressed at a different degree of suppression. Then, each of the calculated correction torques is added according to a weighting coefficient determined based on the traveling state of the vehicle, and a command value of the correction torque for the required braking / driving torque determined by the driver's braking / driving operation is calculated.
Therefore, the braking / driving force control can be performed by changing the degree of emphasis between the fuel efficiency improvement performance and the other performance according to the traveling state of the vehicle.
Therefore, it is possible to achieve both improvement in fuel consumption, steering stability and riding comfort performance.

(2) As another mode, the correction torque calculation means sets the degree of suppression of the pitch fluctuation component and the bounce component among the components constituting the sprung behavior of the vehicle body estimated by the behavior estimation means more than the degree of suppression of other components. It has a high ride comfort mode. Further, the correction torque calculating means has a operability improving mode that promotes the fluctuation of the wheel load among the components constituting the sprung behavior of the vehicle body estimated by the behavior estimating means.
Therefore, it is possible to achieve both improvement in fuel efficiency, ride comfort and maneuverability.

(3) The weighting factor calculating means calculates a weighting factor between the riding comfort improvement mode and the maneuverability improvement mode based on the vehicle speed, and based on the pitch angular velocity of the vehicle body, the fuel consumption improvement mode, the riding comfort improvement mode, and the safety operation mode. The weighting coefficient with the performance improvement mode is calculated.
Therefore, it is possible to perform braking / driving force control that appropriately combines fuel efficiency improvement, riding comfort, and maneuverability in accordance with the traveling state of the vehicle.

(4) In the fuel efficiency improvement mode, the correction torque calculation means multiplies a component constituting the sprung behavior of the vehicle body by a gain that suppresses the pitch variation of the vehicle body.
Therefore, the energy spent for the pitch variation of the vehicle body can be suppressed, and the fuel consumption can be improved.
(5) In the riding comfort improvement mode, the correction torque calculation means multiplies a component that constitutes the sprung behavior of the vehicle body by a gain that suppresses the pitch variation and bounce of the vehicle body.
Therefore, forward leaning, backward leaning, and vertical movement of the vehicle body can be suppressed, and riding comfort can be improved.

(6) In the stability improvement mode, the correction torque calculation means includes differences in the components constituting the sprung behavior of the vehicle body from the pitch variation of the vehicle body, bounce, fluctuations in the longitudinal balance and the reference state of the longitudinal balance. While multiplying the gain to suppress, the component which comprises the sprung behavior of a vehicle body is multiplied by the gain which promotes the wheel load fluctuation | variation which generate | occur | produces at the time of turning.
Therefore, since the wheel load at the time of turning increases while stabilizing the behavior of the vehicle, the steering response can be improved.

(7) The weighting factor calculating means increases the weighting factor of the fuel efficiency improvement mode as compared with other modes as the pitch angular velocity of the vehicle body increases.
Therefore, since the braking / driving force can be applied in a situation where the pitch angular velocity of the vehicle body is large and the energy consumed for pitch fluctuation is large, the fuel efficiency improvement effect can be further enhanced.

(8) The weighting factor calculation means increases the weight of the driving comfort improvement mode as the vehicle speed is higher in the riding comfort improvement mode and the handling improvement mode, and increases the weight of the riding comfort improvement mode as the vehicle speed is lower. Enlarge.
Therefore, it is possible to improve the steering performance even in a high speed range where the steering angle tends to be small. In addition, the ride comfort can be improved even when turning in a low speed range where the steering angle tends to be large.
(9) The weighting factor calculation means has a higher weighting ratio in the fuel consumption improvement mode than in other modes.
Therefore, the priority of the fuel efficiency improvement mode can be increased, and a greater fuel efficiency improvement effect can be realized.

(10) A fuel efficiency improvement mode in which the sprung behavior of the vehicle body is estimated, and among the components constituting the estimated sprung behavior of the vehicle body, the fuel efficiency improvement mode in which the suppression degree of the pitch fluctuation component is set higher than the suppression degree of the other components; The correction torque of the braking / driving force corresponding to the traveling state of the vehicle is calculated based on the other mode set to suppress the component constituting the sprung behavior of the vehicle with the degree of suppression different from the fuel efficiency improvement mode. Then, the correction torque command value for the required braking / driving torque determined by the driver's braking / driving operation is added by adding the correction torque of the fuel efficiency improvement mode and the other mode according to the weight determined according to the traveling state of the vehicle. To do.
Therefore, the braking / driving force control can be performed by changing the degree of emphasis between the fuel efficiency improvement performance and the other performance according to the traveling state of the vehicle.
Therefore, it is possible to achieve both improvement in fuel consumption, steering stability and riding comfort performance.

(Application 1)
In the first embodiment, the weighting factors of the riding comfort improvement mode (B mode) and the maneuverability improvement mode (C mode) are calculated according to the map shown in FIG.
On the other hand, the weighting coefficients of the ride comfort improvement mode (B mode) and the maneuverability improvement mode (C mode) can be set as a map shown in FIG.
FIG. 16 is a diagram illustrating a map in which weighting factors for the ride comfort improvement mode (B mode) and the maneuverability improvement mode (C mode) in Application Example 1 are determined.
In the case of the map shown in FIG. 16, the balance between ride comfort and maneuverability can be increased in the high speed range.

(Application example 2)
In the first embodiment, the weighting factors of the riding comfort improvement mode (B mode) and the maneuverability improvement mode (C mode) are calculated according to the map shown in FIG.
On the other hand, the weighting coefficients of the riding comfort improvement mode (B mode) and the maneuverability improvement mode (C mode) can be made into a map shown in FIG.
FIG. 17 is a diagram illustrating a map in which weighting factors for the ride comfort improvement mode (B mode) and the maneuverability improvement mode (C mode) in Application Example 2 are determined.
In the case of the map shown in FIG. 17, the balance between ride comfort and maneuverability can be improved in the low speed range. In addition, the operability can be improved at high speeds.

  In the above embodiment, the weighting factors of all three modes of the fuel efficiency improvement mode (A mode), the ride comfort improvement mode (B mode), and the maneuverability improvement mode (C mode) are calculated based on the driving situation. It was. On the other hand, it is also possible to set a specific mode having a high priority as a fixed value and calculate and set only other modes based on the driving situation. It is also possible to select which mode is a fixed value (non-calculated value). In this case, as a matter of course, it is not necessary to set the sum of the weighting factors to 1.

1 vehicle, 2 steering angle sensor, 3 accelerator opening sensor, 4 brake pedal depression force sensor, 5 wheel speed sensor, 5FL-5RR wheel, 5BFL-5BRR brake actuator, 6 steering wheel, 7 differential gear, 8 engine, 9 transmission DESCRIPTION OF SYMBOLS 10 Drive shaft, 11 Axle shaft, 12 ECU, 13 Driver request torque calculation part, 14 Adder, 15 Torque command value calculation part, 16 Driving power vehicle system vibration control part, 16A Mode weight coefficient calculation part, 17 Input conversion part , 18 Vehicle vibration estimation unit, 19 Torque command value calculation unit, 20 Drive torque conversion unit, 21 Suspension calculation unit, 22 Vertical force conversion unit, 23 Vehicle body speed estimation unit, 24 Turning behavior estimation unit, 25 Turning resistance estimation unit, 26 Vehicle model, 27 1st regulator, 28 1st Regulator, 29 3rd regulator, 30 1st tuning gain setting part, 31 2nd tuning gain setting part, 32 3rd tuning gain setting part, 33 1st tuning gain multiplication part, 34 2nd tuning gain multiplication part, 35 3rd Tuning gain multiplication unit, 36 engine torque conversion unit, 37 average front wheel speed calculation unit, 38 average rear wheel speed calculation unit, 39 front wheel band pass filter processing unit, 40 rear wheel band pass filter processing unit, 41 front wheel suspension stroke calculation , 42 rear wheel suspension stroke calculating unit, 100 braking / driving torque applying unit, 101 behavior estimating unit, 102 correction torque calculating unit, 103 weight coefficient calculating unit, 104 torque command value calculating unit

Claims (8)

Braking / driving torque applying means for applying braking / driving torque to the wheels;
A behavior estimation means for estimating the sprung behavior of the vehicle body based on the traveling state of the vehicle;
Wherein among the components of the behavior estimation means constitutes a sprung behavior of the vehicle body estimated, fuel efficiency mode to improve the fuel efficiency as compared with the case of setting lower the suppression level by high rather it sets the degree of suppression of the pitch fluctuation component And a correction torque for the braking / driving force corresponding to the driving condition of the vehicle, based on the other modes set to suppress the components constituting the sprung behavior of the vehicle body with a degree of suppression different from the fuel efficiency improvement mode. Correction torque calculation means for
A weighting factor calculating means for calculating a weighting factor of at least one of the fuel efficiency improvement mode and the other mode based on a running state of the vehicle;
The correction torque in the fuel efficiency improvement mode calculated by the correction torque calculation means and the correction torque in the other mode are added according to the weighting coefficients of the fuel efficiency improvement mode and the other modes calculated by the weight coefficient calculation means. A torque command value calculation means for calculating a command value of a correction torque for a required braking / driving torque determined by a driver's braking / driving operation;
I have a,
In the other mode, the correction torque calculation means sets the degree of suppression of the pitch fluctuation component and the bounce component out of the degree of suppression of the other components among the components constituting the sprung behavior of the vehicle body estimated by the behavior estimation means. A ride comfort improvement mode that is set high, and a stability improvement mode that equalizes the degree of suppression of each component that constitutes the sprung behavior of the vehicle body estimated by the behavior estimation means,
The weighting factor calculating means increases the weight of the stability improvement mode as the vehicle speed is higher in the riding comfort improvement mode and the stability improvement mode, and increases the weight of the comfort improvement mode as the vehicle speed is lower. A braking / driving force control device characterized by increasing a weight . The weighting factor calculating means calculates a weighting factor between the riding comfort improving mode and the driving stability improving mode based on the vehicle speed, and based on the pitch angular velocity of the vehicle body, the fuel consumption improving mode, the riding comfort improving mode, and longitudinal force control device according to claim 1, wherein calculating the weight coefficient of the steering stability improvement mode. Wherein the correction torque calculation means in the fuel efficiency mode, the components constituting the sprung behavior of the vehicle body, the braking-driving force according to claim 1, wherein multiplying the suppressing gain of the vehicle body pitch fluctuation Control device. Wherein the correction torque calculation unit, in the ride comfort improvement mode, the components constituting the sprung behavior of the vehicle body, any of claims 1 to 3, characterized by multiplying the suppressing gain pitch variation and bounce of the vehicle body The braking / driving force control device according to claim 1. The correction torque calculation means suppresses the difference between the pitch variation of the vehicle body, the bounce, the fluctuation of the front and rear axis balance, and the reference state of the front and rear axis balance in the component constituting the sprung behavior of the vehicle body in the stability improvement mode. while multiplying the gain of, the components constituting the sprung behavior of the vehicle body, according to any one of claims 1 4, characterized by multiplying the gain for promoting wheel load variation occurring during turning Braking / driving force control device. It said weighting factor calculating means, as the vehicle body pitch angular velocity is large, control according to any one of claims 1 to 5, characterized in that to increase the weighting factor of the fuel efficiency mode than the other modes Driving force control device. The braking / driving force control device according to any one of claims 1 to 6 , wherein the weighting factor calculation means increases a weighting ratio of the fuel consumption improvement mode with respect to the other modes. Estimating a sprung behavior of the vehicle body, among the components constituting the sprung behavior of the estimated vehicle body, improve fuel consumption as compared with the case of setting lower the suppression level by high rather it sets the degree of suppression of the pitch fluctuation component Of the braking / driving force corresponding to the traveling state of the vehicle based on the fuel efficiency improvement mode to be controlled and other modes set to suppress the components constituting the sprung behavior of the vehicle body with a degree of suppression different from the fuel efficiency improvement mode. The required braking / driving torque determined by the driver's braking / driving operation is calculated by calculating the correction torque and adding the correction torques of the fuel efficiency improvement mode and the other modes according to the weights determined according to the traveling state of the vehicle. The correction torque command value for
As the other modes, among the components constituting the sprung behavior of the vehicle body, a ride comfort improvement mode in which the degree of suppression of the pitch fluctuation component and the bounce component is set higher than the degree of suppression of the other components, and the sprung behavior of the vehicle body And a stability improvement mode that equalizes the degree of suppression of each component constituting the
In the riding comfort improvement mode and the driving stability improvement mode, the weight of the driving comfort improvement mode is increased as the vehicle speed is higher, and the weight of the riding comfort improvement mode is increased as the vehicle speed is lower. The braking / driving force control method.

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