JP2020164158A - Control device of vehicle - Google Patents

Abstract

To provide a control device of a vehicle which can suppress the impartment of an incongruity to an occupant of the vehicle at a start of the vehicle.SOLUTION: A posture control device 40 as a control device comprises a posture control part 42 for performing posture control for indicating a brake device 20 to decrease a front wheel brake force and a rear wheel brake force when a vehicle is stopped on a slope due to the impartment of the brake force to a front wheel 11 and a rear wheel 12, and indicating a drive unit 30 to increase the drive force of the vehicle within a range in which the stop of the vehicle is maintained, and a brake increase indication part 43 for performing brake increase control for indicating the brake device 20 to increase the brake force of at least one wheel out of the front wheel 11 and the rear wheel 12 after a finish of the increase of the drive force of the vehicle resulting from the execution of the posture control.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle control device that controls a braking device and a driving device.

Patent Document 1 describes an example of a vehicle control device for stopping a vehicle on an uphill road. In this control device, the driving force of the vehicle is reduced by controlling the driving device, and the braking force of the vehicle is increased by controlling the braking device, so that the vehicle is stopped on an uphill road.

JP-A-2018-96064

By the way, when braking the vehicle, the vehicle may pitch on the nose dive side. In this case, the contraction of the suspension for the front wheels and the extension of the suspension for the rear wheels may change the front-rear position of at least one of the front wheels and the rear wheels, and may change the wheelbase of the vehicle. When the braking force is continuously applied to at least one of the wheels, the suspension is contracted or extended due to the frictional force between the wheel and the road surface and the braking force applied to the wheel. The operation of the suspension to return to the original position is restricted, that is, the displacement of the wheel to return the front-rear position of the wheel to the original position is regulated. Therefore, when the braking force applied to each wheel is released when the vehicle is started, the suspension operation restriction is released, the suspension state returns to the original state, and at least one of the wheels The front-back position returns to the original position. As a result, the changed state of the wheelbase of the vehicle is eliminated. At this time, the posture of the vehicle may change suddenly due to the change in the wheelbase. In addition, a sound may be generated due to a sudden change in vehicle attitude. The occupants of the vehicle may feel uncomfortable with respect to such a sudden change in the vehicle posture at the time of starting.

The vehicle control device for solving the above problems is a device that controls a vehicle drive device and a braking device. When the vehicle is stopped on a slope by applying braking force to the front and rear wheels of the vehicle, this control device instructs the braking device to reduce the braking force of the front wheels and the braking force of the rear wheels. After the attitude control unit that executes the attitude control instructing the drive device to increase the driving force of the vehicle within the range of maintaining the stop of the vehicle and the end of the increase in the driving force of the vehicle due to the execution of the attitude control, A braking increase instruction unit for instructing the braking device to increase the braking force of at least one of the front wheels and the rear wheels is provided.

According to the above configuration, attitude control is performed when the vehicle is stopped on a slope by applying braking force to the front wheels and the rear wheels. When an instruction based on attitude control is input to the braking device and the driving device, the braking force of the front wheels and the rear wheels is reduced. In addition, the driving force of the vehicle is increased so that the stopping of the vehicle is maintained even if the braking force of the vehicle is reduced. As a result, even if the front-rear position of at least one of the front wheels and the rear wheels is displaced when the vehicle is stopped and the wheelbase of the vehicle is changed, the vehicle is maintained at the stop by implementing the attitude control. At the same time, the position of at least one of the wheels in the front-rear direction can be restored. That is, the wheelbase can be returned to its original position while the vehicle is stopped. Then, after the increase in the driving force for maintaining the stop of the vehicle is completed, the braking force of the vehicle is increased due to the implementation of the braking increase control. Therefore, when the braking of the vehicle is released when the vehicle starts after that, a sudden change in the vehicle attitude due to the change in the wheelbase does not occur. Therefore, it is possible to prevent the occupants of the vehicle from being uncomfortable when the vehicle is started.

The block diagram which shows the attitude control device which is a control device of the vehicle of 1st Embodiment, a drive device, and a braking device. Schematic diagram of a vehicle equipped with the same attitude control device. Schematic diagram showing how the vehicle travels on an uphill road. Schematic diagram showing how the vehicle stopped on an uphill road. The flowchart explaining the processing routine executed by the attitude control device. The flowchart explaining the processing routine executed by the attitude control device. A flowchart illustrating a processing routine for instructing a decrease in the braking force of the first wheel and an increase in the driving force of the vehicle. A flowchart illustrating a processing routine for instructing an increase in driving force of a vehicle. The flowchart explaining the processing routine for instructing the reduction of the braking force of the 2nd wheel. A flowchart illustrating a processing routine for instructing an increase in the braking force of the second wheel and a decrease in the driving force of the vehicle. A flowchart illustrating a processing routine for instructing an increase in braking force of a first wheel and a decrease in driving force of a vehicle. (A) to (f) are timing charts in the first embodiment. (A) to (f) are timing charts in the first embodiment. A flowchart illustrating a processing routine for instructing an increase in driving force of a vehicle in a second embodiment. (A) to (f) are timing charts in the second embodiment. (A) to (f) are timing charts in the third embodiment. (A) to (f) are timing charts in the modified example.

(First Embodiment)
Hereinafter, the first embodiment of the vehicle control device will be described with reference to FIGS. 1 to 13.
FIG. 1 shows an attitude control device 40, a braking device 20, and a driving device 30, which are examples of the control device of the present embodiment. The drive device 30 has a power unit 31 and a drive control unit 32 that controls the power unit 31. The power unit 31 has at least one of an engine and an electric motor as a power source for the vehicle. The drive control unit 32 adjusts the drive force DP of the vehicle by controlling the power unit 31. As shown in FIGS. 1 and 2, the power unit 31 outputs the driving force DP to the front wheels 11 among the plurality of wheels 11 and 12 provided in the vehicle, while driving the rear wheels 12. Does not output force DP. That is, in the present embodiment, the front wheel 11 corresponds to the "first wheel" and the rear wheel 12 corresponds to the "second wheel".

As shown in FIG. 1, the braking device 20 includes a braking actuator 21 and a braking control unit 22 that controls the braking actuator 21. As shown in FIGS. 1 and 2, the braking actuator 21 is configured to be able to individually control the braking force of the front wheels 11 and the braking force of the rear wheels 12. The braking force of the front wheels 11 is also referred to as "front wheel braking force BPF", and the braking force of the rear wheels 12 is also referred to as "rear wheel braking force BPR". The braking control unit 22 adjusts the braking force BP of the vehicle by controlling the braking actuator 21. The braking force BP of the vehicle is the sum of the braking forces of all the wheels 11 and 12.

With reference to FIGS. 3 and 4, the transition of the vehicle posture when the vehicle 10 decelerates and stops will be described.
As shown in FIG. 3, when the vehicle 10 is decelerating due to the application of braking force to the front wheels 11 and the rear wheels 12, the vehicle 10 pitches toward the nose dive side. In this case, the front wheel suspension 13F, which is the suspension provided for the front wheels 11, contracts due to the pitching moment accompanying the deceleration, while the rear wheel suspension 13R, which is the suspension provided for the rear wheels 12, contracts. Stretches. At the same time, due to the geometry of the suspensions 13F and 13R, an anti-dive force is generated in the front part of the vehicle body 16 due to the application of the braking force to the front wheels 11, and the braking force to the rear wheels 12 is generated in the rear part of the vehicle body 16. Anti-lift force is generated with the grant. The anti-dive force is a force that displaces the front portion of the vehicle body 16 upward. The anti-lift force is a force that displaces the rear portion of the vehicle body 16 downward. Further, when the vehicle 10 is decelerating, as shown by the white arrows in FIG. 3, the frictional forces FF1 and FF2 are on the contact patch with the road surface on the wheels 11 and 12 under the slope behind the vehicle 10. Acts on the side. The frictional force FF1 acting on the contact patch with the road surface of the front wheels 11 is referred to as "first contact patch friction force FF1", and the frictional force FF2 acting on the contact patch with the road surface of the rear wheels 12 is referred to as "first contact patch friction force FF1". Second contact patch friction force FF2 ".

In the vehicle 10 shown in FIG. 3, the position of the vehicle front-rear direction X at the end of the front wheel suspension 13F on the front wheel 11 side is different from the position of the vehicle front-rear direction X at the end of the front wheel suspension 13F on the vehicle body 16 side. However, the front wheel suspension 13F is provided so that the end of the front wheel suspension 13F on the vehicle body 16 side is used as a fulcrum. Similarly, the position of the vehicle front-rear direction X at the end of the rear wheel suspension 13R on the rear wheel 12 side is different from the position of the vehicle front-rear direction X at the end of the rear wheel suspension 13R on the vehicle body 16 side, and is for the rear wheels. The rear wheel suspension 13R is provided so that the end of the suspension 13R on the vehicle body 16 side is used as a fulcrum. Therefore, when the front wheel suspension 13F is displaced in the vertical direction such as the front wheel suspension 13F contracting as described above, the position of the front wheel 11 in the vehicle front-rear direction X differs from the reference position of the front wheel 11. The reference position of the front wheels 11 is the position of the front wheels 11 in the vehicle front-rear direction X when the front wheel suspension 13F is positioned at a position in the vertical direction in the stop reference state. Further, when the rear wheel suspension 13R is displaced in the vertical direction such that the rear wheel suspension 13R is extended as described above, the position of the rear wheel 12 in the vehicle front-rear direction X is different from the reference position of the rear wheel 12. .. The reference position of the rear wheel 12 is the position of the rear wheel 12 in the vehicle front-rear direction X when the rear wheel suspension 13R is positioned at a position in the vertical direction in the stop reference state.

The stop reference state is, for example, a state in which a force that is not generated during the stop is not acting when the vehicle 10 is stopped on the road surface on which the vehicle 10 is currently located. That is, the stop reference state when the vehicle 10 is stopped on an uphill road having an inclination α is, for example, a state in which the vehicle 10 is placed on a horizontal plate and a sufficient braking force is applied to the vehicle 10. Corresponds to a state in which one of the plates in the front-rear direction is lifted and the inclination of the vehicle 10 in the front-rear direction is defined as inclination α. Further, the stop reference state when the vehicle 10 is stopped on the uphill road of the inclination α is that the vehicle 10 is advanced by inertia on the uphill road of the inclination α without applying both braking force and driving force, and is due to gravity. When the vehicle body speed VS becomes "0 (zero)" due to deceleration, the braking force is momentarily increased to a size sufficient to maintain the stopped state of the vehicle 10 so that the vehicle 10 is stopped. Equivalent to.

When the position of at least one of the front wheels 11 and the rear wheels 12 in the vehicle front-rear direction X is displaced from the reference position of the wheels, the wheelbase WBL of the vehicle differs from the reference wheelbase WBLB. The reference wheelbase WBLB is a wheelbase when the front wheels 11 are located at the reference positions of the front wheels 11 and the rear wheels 12 are located at the reference positions of the rear wheels 12. The types of suspensions 13F and 13R shown in FIG. 3 are examples. If the suspension is displaced in the vertical direction due to braking and the position of the wheel in the vehicle front-rear direction X changes from the reference position during braking, Other types of suspension may be adopted as suspensions 13F and 13R.

When the vehicle 10 is stopped on an uphill road by applying a braking force to the wheels 11 and 12, the gravity applied to the vehicle 10 acts on the vehicle 10 as a sliding force. Therefore, when the vehicle 10 is stopped on an uphill road, as shown by the white arrows in FIG. 3, the contact patch with the road surface on each of the wheels 11 and 12 is in contact with the upper slope in front of the vehicle 10. Ground friction forces FF1 and FF2 act. That is, the directions of the ground contact surface friction forces FF1 and FF2 change before and after the vehicle 10 is stopped.

Further, when the braking force is continuously applied to the front wheels 11 even after the vehicle 10 is stopped, the front wheels 11 are in a locked state in which the rotation is restricted by the front wheel braking force BPF. As a result, the displacement of the front wheels 11 that returns the position of the front wheels 11 in the vehicle front-rear direction X to the reference position is regulated by the influence of the first contact patch friction force FF1 between the front wheels 11 and the road surface and the front wheel braking force BPF. Will be done. That is, the operation of the front wheel suspension 13F that returns the vertical position of the front wheel suspension 13F to the vertical position in the stop reference state is restricted. Similarly, when the braking force is continuously applied to the rear wheels 12 even after the vehicle 10 is stopped, the rear wheels 12 are in a locked state in which the rotation is restricted by the rear wheel braking force BPR. As a result, due to the influence of the second ground contact surface friction force FF2 between the rear wheels 12 and the road surface and the rear wheel braking force BPR, the position of the rear wheels 12 in the vehicle front-rear direction X is returned to the reference position. Displacement is regulated. That is, the operation of the rear wheel suspension 13R is restricted so as to return the vertical position of the rear wheel suspension 13R to the vertical position in the stop reference state. The vertical positions of the suspensions 13F and 13R referred to here are the vertical positions of the wheels 11 and 12 with respect to the vehicle body 16 due to the contraction and extension of the suspensions 13F and 13R.

As shown in FIG. 1, the vehicle 10 is provided with various sensors. Examples of the sensor include a wheel speed sensor 101 and a front-rear acceleration sensor 102. The wheel speed sensor 101 is provided for each of the wheels 11 and 12. Then, the wheel speed sensor 101 detects the wheel speed VW of the corresponding wheels 11 and 12, and outputs a signal corresponding to the detected wheel speed VW as a detection signal. The front-rear acceleration sensor 102 detects the front-rear acceleration GX, which is the acceleration in the front-rear direction X of the vehicle, and outputs a signal corresponding to the detected front-rear acceleration GX as a detection signal.

A detection signal from the wheel speed sensor 101 and a detection signal from the front-rear acceleration sensor 102 are input to the attitude control device 40. In the attitude control device 40, the vehicle body speed VS of the vehicle 10 is derived based on the wheel speed VW of the wheels 11 and 12 based on the detection signal from each wheel speed sensor 101. Further, in the attitude control device 40, the time-differentiated value of the vehicle body speed VS is derived as the vehicle body acceleration DVS of the vehicle.

The attitude control device 40 has a slope determination unit 41, an attitude control unit 42, a braking increase instruction unit 43, and a drive decrease instruction unit 44 as functional units for adjusting the vehicle attitude when the vehicle 10 stops on a slope. There is.

The slope determination unit 41 determines whether or not the road surface on which the vehicle 10 is stopped is an uphill road. That is, when the vehicle 10 stops, the slope determination unit 41 derives the road surface gradient θ, which is the slope of the road surface, and makes a determination based on the road surface gradient θ. For example, the slope determination unit 41 calculates the value obtained by subtracting the vehicle body acceleration DVS from the front-rear acceleration GX as the road surface gradient θ. When the vehicle is stopped on an uphill road, the front-rear acceleration GX is larger than the vehicle body acceleration DVS, so that the road surface gradient θ is a positive value. Therefore, the slope determination unit 41 determines that the road surface is an uphill road when the road surface gradient θ is equal to or higher than the uphill road determination value θTh1. On the other hand, the slope determination unit 41 does not determine that the road surface is an uphill road when the road surface gradient θ is less than the uphill road determination value θTh1.

The attitude control unit 42 performs attitude control when the vehicle 10 is stopped and the slope determination unit 41 determines that the road surface is an uphill road. Attitude control is a control in which the braking device 20 is instructed to reduce the front wheel braking force BPF and the rear wheel braking force BPR, and the driving device 30 is instructed to increase the driving force DP of the vehicle within the range in which the vehicle 10 is maintained at rest. Is. Attitude control includes a first braking reduction instruction process, a second braking reduction instruction process, a first drive increase instruction process, and a second drive increase instruction process. The start timing of each process and the content of each process will be described later.

The braking increase instruction unit 43 instructs the braking device 20 to increase at least one of the front wheel braking force BPF and the rear wheel braking force BPR after the increase in the driving force DP of the vehicle due to the implementation of the attitude control is completed. Implement augmentation control. In the present embodiment, the braking increase instruction unit 43 instructs the braking device 20 to increase both the front wheel braking force BPF and the rear wheel braking force BPR in the braking increase control. The braking increase control includes a first braking increase instruction process and a second brake increase instruction process. The start timing of each process and the content of each process will be described later.

The drive reduction instruction unit 44 implements the drive reduction control for instructing the drive device 30 to decrease the driving force DP after the increase in the driving force DP of the vehicle due to the execution of the attitude control by the attitude control unit 42 is completed. The drive reduction control includes a first drive reduction instruction process and a second drive reduction instruction process. The start timing of each process and the content of each process will be described later.

Next, the processing routine executed by the attitude control device 40 will be described with reference to FIGS. 5 to 11. The series of processing routines shown in FIGS. 5 to 11 are repeatedly executed when the vehicle 10 is located on an uphill road.

First, the main processing routine shown in FIG. 5 will be described.
In this processing routine, in step S11, it is determined whether or not the vehicle 10 is stopped. For example, when the vehicle body speed VS is "0 (zero)", it is determined that the vehicle 10 is stopped, while when the vehicle body speed VS is not "0 (zero)", the vehicle 10 is stopped. Do not judge that it is. If it is not determined that the vehicle 10 is stopped (S11: NO), the process proceeds to the next step S12. In step S12, the current second indicated braking force BPTr2 is set as the braking force BP2b before the second stop. The second indicated braking force BPTr2 is an indicated value of the braking force of the second wheel. When the braking force BP of the vehicle 10 is adjusted by automatic braking, the indicated value of the braking force of the second wheel determined by the control device for automatic braking is set as the second indicated braking force BPTr2. On the other hand, when the braking force BP of the vehicle 10 is adjusted by the braking operation of the driver, the braking force of the second wheel at the present time is set as the second indicated braking force BPTr2. Since the rear wheel 12 corresponds to the second wheel in the present embodiment, the second indicated braking force BPTr2 is either the indicated value of the braking force of the rear wheel 12 at the present time or the rear wheel braking force BPR at the present time. One is set. When the braking force BP2b before the second stop is set, the process shifts to the next step S13.

In step S13, the controlling flag FLG1 and the control completion flag FLG2 are set to off, respectively. In addition, the stop counter CNT and the step counter CNT are reset to "0 (zero)", respectively. The controlling flag FLG1 is a flag that is set to be ON when at least one of attitude control, braking increase control, and drive decrease control is being controlled. The control completion flag FLG2 is a flag that is set to be turned on when all of the attitude control, the braking increase control, and the drive decrease control are completed. The stop counter CNT is a counter that is updated to measure the start timing of attitude control. The step counter CNTS is a counter that is updated when switching various processes described later. After that, this processing routine is temporarily terminated.

On the other hand, if it is determined in step S11 that the vehicle 10 is stopped (YES), the process proceeds to the next step S14. In step S14, it is determined whether or not the control completion flag FLG2 is set to ON. When the control completion flag FLG2 is set to ON, all of the attitude control, the braking increase control, and the drive decrease control are completed. On the other hand, when the control completion flag FLG2 is set to off, none of the attitude control, the braking increase control and the drive decrease control has been implemented yet, or among the attitude control, the braking increase control and the drive decrease control. At least one control is in progress. When the control completion flag FLG2 is set to ON (S14: YES), this processing routine is temporarily terminated. On the other hand, when the control completion flag FLG2 is set to off (S14: NO), the process proceeds to the next step S15.

In step S15, it is determined whether or not the controlling flag FLG1 is set to ON. When the controlling flag FLG1 is set to ON, at least one of attitude control, braking increase control, and drive decrease control is being performed. On the other hand, when the controlling flag FLG1 is set to off, none of the attitude control, the braking increase control, and the drive decrease control has been implemented yet. When the controlling flag FLG1 is set to ON (S15: YES), the process proceeds to the next step S16.

In step S16, it is determined whether or not there is a start instruction for the vehicle 10. When the vehicle 10 is driven by automatic driving, a transmission instruction is input to the attitude control device 40 from the control device for automatic driving. Therefore, when the start instruction is input to the attitude control device 40, it is determined that there is a start instruction. On the other hand, when the vehicle 10 is driven manually by the driver, when it is detected that the accelerator operation has been started, it is determined that there is a start instruction. When a sudden release of the braking operation is detected, it may be determined that there is a start instruction. If it is not determined that there is a start instruction (S16: NO), the process proceeds to step S23, which will be described later. That is, the ongoing control is continued.

On the other hand, when it is determined that there is a start instruction (S16: YES), the process proceeds to the next step S17. In step S17, "0 (zero)" is set as the first indicated driving force DPTr1 which is an indicated value of the driving force input to the first wheel. Since the front wheel 11 corresponds to the first wheel in the present embodiment, the first indicated driving force DPTr1 is an indicated value of the driving force input to the front wheel 11. Then, the process proceeds to step S13 described above.

On the other hand, in step S15, when the controlling flag FLG1 is set to off (NO), the process proceeds to the next step S18. In step S18, the stop counter CNT is incremented by "1". Subsequently, in step S19, it is determined whether or not the stop counter CNT updated in step S18 is larger than the control start determination value CNTTh. The control start determination value CNTTh is set as a criterion for determining whether to allow the start of attitude control based on the size of the stop counter CNT corresponding to the duration of the state in which the vehicle 10 is stopped. When the stop counter CNT is equal to or less than the control start determination value CNTTh (S19: NO), this processing routine is temporarily terminated. That is, attitude control has not yet started.

On the other hand, when the stop counter CNT is larger than the control start determination value CNTTh (S19: YES), the process proceeds to the next step S20. In step S20, the controlling flag FLG1 is set to ON, and the step counter CNTS is incremented by "1". Subsequently, in step S21, the stop holding force Fh is derived. The stop holding force Fh is a force required to maintain the state in which the vehicle 10 stops on an uphill road. That is, the stop holding force Fh is a force required to maintain the stop of the vehicle 10 against the action of gravity. The stop holding force Fh is derived based on the road surface gradient θ of the uphill road where the vehicle 10 is stopped. Specifically, the stop holding force Fh increases as the road surface gradient θ increases. Then, in step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, the current second indicated braking force BPTr2 is set as the second braking force previous value BP2a, and the current first The indicated driving force DPTr1 is set as the first driving force previous value DP1a. The first indicated braking force BPTr1 is an indicated value of the braking force of the first wheel. Since the front wheel 11 corresponds to the first wheel in the present embodiment, either one of the indicated value of the braking force of the front wheel 11 and the current front wheel braking force BPF is set as the first indicated braking force BPTr1. To. Then, when the process of step S22 is completed, the process shifts to the next step S23.

In step S23, a process for adjusting the control driving force is executed. The process will be described later. Then, when the process is executed, the present process routine is once terminated.
Next, the process of step S23 will be described with reference to FIG.

In this processing routine, in step S31, it is determined whether or not the step counter CNTS is "1". When it is determined that the step counter CNTS is "1" (S31: YES), the process proceeds to the next step S32. In step S32, the attitude control unit 42 executes the attitude control first braking reduction instruction process and the first drive increase instruction process. The first braking reduction instruction process is a process of instructing the braking control unit 22 to reduce the braking force of the first wheel. The first drive increase instruction process is a process of instructing the drive control unit 32 to increase the drive force of the first wheel, that is, the drive force DP of the vehicle 10. This first drive increase instruction process is one of the drive increase instruction processes for instructing the drive device 30 to increase the driving force DP of the vehicle 10 within the range of maintaining the stop of the vehicle 10. The specific contents of the first braking reduction instruction processing and the first drive increase instruction processing will be described later. When the first braking reduction instruction processing and the first drive increase instruction processing are executed, this processing routine is terminated.

If it is not determined in step S31 that the step counter CNTS is "1" (NO), the process proceeds to the next step S33. In step S33, it is determined whether or not the step counter CNTS is "2". When it is determined that the step counter CNTS is "2" (S33: YES), the process proceeds to the next step S34. In step S34, the attitude control unit 42 executes the attitude control second drive increase instruction process. The second drive increase instruction process is a process of instructing the drive control unit 32 to increase the drive force of the first wheel, that is, the drive force DP of the vehicle 10. That is, the second drive increase instruction process is also one of the drive increase instruction processes. The specific content of the second drive increase instruction process will be described later. When the second drive increase instruction process is executed, this process routine is terminated.

If it is not determined in step S33 that the step counter CNTS is "2" (NO), the process proceeds to the next step S35. In step S35, it is determined whether or not the step counter CNTS is "3". When it is determined that the step counter CNTS is "3" (S35: YES), the process proceeds to the next step S36. In step S36, the attitude control unit 42 executes the attitude control second braking reduction instruction process. The second braking reduction instruction process is a process of instructing the braking control unit 22 to reduce the braking force of the second wheel. The specific content of the second braking reduction instruction processing will be described later. When the second braking reduction instruction process is executed, this process routine is terminated.

If it is not determined in step S35 that the step counter CNTS is “3” (NO), the process proceeds to the next step S37. In step S37, it is determined whether or not the step counter CNTS is "4". When it is determined that the step counter CNTS is “4” (S37: YES), the process proceeds to the next step S38. In step S38, the second braking increase instruction process of the braking increase control is executed by the braking increase instruction unit 43, and the first drive decrease instruction process of the drive decrease control is executed by the drive decrease instruction unit 44. The second braking increase instruction process is a process of instructing the braking control unit 22 to increase the braking force of the second wheel. The first drive reduction instruction process is a process of instructing the drive control unit 32 to reduce the driving force of the first wheel. The specific contents of the second braking increase instruction process and the first drive decrease instruction process will be described later. When the second braking increase instruction process and the first drive decrease instruction process are executed, this processing routine is terminated.

In step S37, if it is not determined that the step counter CNTs are “4” (NO), the step counter CNTs is “5”, so the process proceeds to the next step S39. In step S39, the first braking increase instruction process of the braking increase control is executed by the braking increase instruction unit 43, and the second drive decrease instruction process of the drive decrease control is executed by the drive decrease instruction unit 44. The first braking increase instruction process is a process of instructing the braking control unit 22 to increase the braking force of the first wheel. The second drive reduction instruction process is a process of instructing the drive control unit 32 to reduce the driving force of the first wheel. The specific contents of the first braking increase instruction process and the second drive decrease instruction process will be described later. When the first braking increase instruction process and the second drive decrease instruction process are executed, this processing routine is terminated.

Next, with reference to FIG. 7, the first braking reduction instruction processing and the first drive increase instruction processing in step S32 will be described. This processing routine is executed by the attitude control unit 42.
In this processing routine, the first braking reduction instruction processing is executed. In the first step S51, in the first braking reduction instruction processing, the value obtained by subtracting the first braking reduction amount ΔBP1 from the first braking force previous value BP1a is calculated as the latest first instruction braking force BPTr1. A positive value is set as the first braking reduction amount ΔBP1. Subsequently, in step S52, it is determined whether or not the first indicated braking force BPTr1 calculated in step S51 is "0 (zero)" or less. When the first indicated braking force BPTr1 is "0 (zero)" or less (S52: YES), the process proceeds to the next step S53. In step S53, “0 (zero)” is set as the first indicated braking force BPTr1, and the step counter CNTS is incremented by “1”. That is, the step counter CNTS becomes "2". Then, the process proceeds to the next step S54. On the other hand, in step S52, when the first indicated braking force BPTr1 is larger than "0 (zero)" (NO), the process shifts to the next step S54. That is, the step counter CNTS is held at "1".

In step S54, an output process for outputting the first indicated braking force BPTr1 and the second indicated braking force BPTr2 to the braking device 20 is executed. While the execution of this processing routine is repeated, the first indicated braking force BPTr1 output to the braking device 20 continues to decrease. Therefore, outputting the first instruction braking force BPTr1 to the braking device 20 through the execution of this processing routine corresponds to instructing the braking device 20 to reduce the braking force of the first wheel. Then, the process to be executed is shifted from the first braking decrease instruction process to the first drive increase instruction process.

When the first indicated braking force BPTr1 and the second indicated braking force BPTr2 are input by executing the output process, the braking control unit 22 follows the first indicated braking force BPTr1 with the braking force of the first wheel. , The braking actuator 21 is controlled so that the braking force of the second wheel follows the second indicated braking force BPTr2. In the first braking reduction instruction processing, the first instruction braking force BPTr1 is reduced, while the second instruction braking force BPTr2 is retained. Therefore, by inputting an instruction based on the execution of the first braking reduction instruction process to the braking control unit 22, the braking force of the second wheel is maintained, and the speed corresponding to the first braking reduction amount ΔBP1 is increased. The braking force of one wheel can be reduced.

In the first step S55 in the first drive increase instruction process, it is determined whether or not the sum of the first instruction braking force BPTr1 and the above-mentioned second braking force previous value BP2a is equal to or more than the above-mentioned stop holding force Fh. Will be. When the sum is equal to or greater than the stop holding force Fh, the stop holding of the vehicle 10 can be held by making the braking force of the first wheel equal to the first indicated braking force BPTr1. On the other hand, when the sum is less than the stop holding force Fh, there is a possibility that the stop of the vehicle 10 cannot be held even if the braking force of the first wheel is equal to the first indicated braking force BPTr1.

When the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a is equal to or greater than the stop holding force Fh (S55: YES), the process proceeds to the next step S56. In step S56, "0 (zero)" is set as the first instruction driving force DPTr1. Then, the process proceeds to step S58, which will be described later. On the other hand, when the sum is less than the stop holding force Fh (S55: NO), the process proceeds to the next step S57. In step S57, the value obtained by subtracting the stop holding force Fh from the sum is calculated as the first instruction driving force DPTr1. When this processing routine is repeatedly executed, the first indicated braking force BPTr1 is reduced, so that the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a gradually becomes smaller. Therefore, in the first drive increase instruction process, the first instruction drive force DPTr1 is increased at a speed corresponding to the decrease speed of the first instruction braking force BPTr1. Then, the process proceeds to the next step S58.

In step S58, an output process for outputting the first instruction driving force DPTr1 to the driving device 30 is executed. While the execution of this processing routine is repeated, the first instruction driving force DPTr1 output to the driving device 30 continues to increase. Therefore, outputting the first instruction driving force DPTr1 to the driving device 30 through the execution of this processing routine corresponds to instructing the driving device 30 to increase the driving force DP of the vehicle 10.

When the first indicated driving force DPTr1 is input by executing the output process, the drive control unit 32 controls the power unit 31 so that the driving force DP follows the first indicated driving force DPTr1. As a result, the driving force DP of the vehicle 10 can be increased within a range in which the vehicle 10 can be maintained at rest.

When the output process is executed, the process proceeds to the next step S59. In step S59, similarly to step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, and the current second indicated braking force BPTr2 is set as the second braking force previous value BP2a. , The current first indicated driving force DPTr1 is set as the first driving force previous value DP1a. After that, this processing routine is terminated.

When this processing routine is terminated while the step counter CNTS is "1", the first braking reduction instruction processing and the first drive increase instruction processing are continued, respectively. On the other hand, when this processing routine is terminated while the step counter CNTS is "2", the first braking reduction instruction processing and the first drive increase instruction processing are terminated, respectively.

Next, with reference to FIG. 8, the second drive increase instruction process in step S34 will be described. This processing routine is executed by the attitude control unit 42.
In this processing routine, in step S71, the sum of the first driving force previous value DP1a and the first driving increase amount ΔDP1 is calculated as the latest first instruction driving force DPTr1. A positive value derived from the specifications of the power unit 31 is set as the first drive increase amount ΔDP1. Subsequently, in step S72, it is determined whether or not the first instruction driving force DPTr1 calculated in step S71 is equal to or greater than the above-mentioned stop holding force Fh. When the first indicated driving force DPTr1 is equal to or greater than the stop holding force Fh, the vehicle 10 may start when the braking force BP of the vehicle 10 becomes “0 (zero)”. Therefore, when the first instruction driving force DPTr1 is equal to or greater than the stop holding force Fh (S72: YES), the process proceeds to the next step S73. In step S73, the stop holding force Fh is set as the first instruction driving force DPTr1, and the step counter CNTS is incremented by "1". That is, the step counter CNTS becomes "3". Then, the process proceeds to the next step S74.

On the other hand, in step S72, when the first instruction driving force DPTr1 is less than the stop holding force Fh (NO), the process proceeds to the next step S74. That is, the step counter CNTS is held at "2".

In step S74, an output process for outputting the first instruction driving force DPTr1 to the driving device 30 is executed. While the execution of this processing routine is repeated, the first instruction driving force DPTr1 output to the driving device 30 continues to increase. Therefore, outputting the first instruction driving force DPTr1 to the driving device 30 through the execution of this processing routine corresponds to instructing the driving device 30 to increase the driving force DP of the vehicle 10.

When the first indicated driving force DPTr1 is input by executing the output process, the drive control unit 32 controls the power unit 31 so that the driving force DP follows the first indicated driving force DPTr1. As a result, the driving force DP of the vehicle can be increased at a speed corresponding to the first driving increase amount ΔDP1.

When the output process is executed, the process proceeds to the next step S75. In step S75, similarly to step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, and the current second indicated braking force BPTr2 is set as the second braking force previous value BP2a. , The current first indicated driving force DPTr1 is set as the first driving force previous value DP1a. After that, this processing routine is terminated.

If this processing routine is terminated while the step counter CNTS is "2", the second drive increase instruction processing is continued. On the other hand, when this processing routine is terminated while the step counter CNTS is "3", the second drive increase instruction processing is terminated.

Next, with reference to FIG. 9, the second braking reduction instruction process in step S36 will be described. This processing routine is executed by the attitude control unit 42.
In this processing routine, in step S91, the value obtained by subtracting the second braking reduction amount ΔBP2 from the above-mentioned second braking force previous value BP2a is calculated as the latest second indicated braking force BPTr2. A positive value is set as the second braking reduction amount ΔBP2. The second braking reduction amount ΔBP2 may be the same as the first braking reduction amount ΔBP1, may be smaller than the first braking reduction amount ΔBP1, or may be larger than the first braking reduction amount ΔBP1. Subsequently, in step S92, it is determined whether or not the second indicated braking force BPTr2 calculated in step S91 is "0 (zero)" or less. When the second indicated braking force BPTr2 is "0 (zero)" or less (S92: YES), the process proceeds to the next step S93. In step S93, “0 (zero)” is set as the second indicated braking force BPTr2, and the step counter CNTS is incremented by “1”. That is, the step counter CNTS becomes "4". Then, the process proceeds to the next step S94. On the other hand, in step S92, when the second indicated braking force BPTr2 is larger than "0 (zero)" (NO), the process shifts to the next step S94. That is, the step counter CNTS is held at "3".

In step S94, an output process is executed in which the first indicated braking force BPTr1 and the second indicated braking force BPTr2 are output to the braking device 20, and the first indicated driving force DPTr1 is output to the driving device 30. While the execution of this processing routine is repeated, the second indicated braking force BPTr2 output to the braking device 20 continues to decrease. Therefore, outputting the second instruction braking force BPTr2 to the braking device 20 through the execution of this processing routine corresponds to instructing the braking device 20 to reduce the braking force of the second wheel.

When the first indicated braking force BPTr1 and the second indicated braking force BPTr2 are input by executing the output process, the braking control unit 22 follows the first indicated braking force BPTr1 with the braking force of the first wheel. , The braking actuator 21 is controlled so that the braking force of the second wheel follows the second indicated braking force BPTr2. In the second braking reduction instruction processing, the first instruction braking force BPTr1 is maintained, while the second instruction braking force BPTr2 is reduced. Therefore, by inputting an instruction based on the execution of the second braking reduction instruction processing to the braking control unit 22, the braking force of the first wheel is maintained and the speed corresponding to the second braking reduction amount ΔBP2 is increased. The braking force of the two wheels can be reduced. Further, the first instruction driving force DPTr1 is not changed in the execution of the second braking reduction instruction process. Therefore, the driving force DP of the vehicle 10 is maintained by inputting an instruction based on the execution of the second braking reduction instruction processing to the drive control unit 32.

When the output process is executed, the process proceeds to the next step S95. In step S95, similarly to step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, and the current second indicated braking force BPTr2 is set as the second braking force previous value BP2a. , The current first indicated driving force DPTr1 is set as the first driving force previous value DP1a. After that, this processing routine is terminated.

When this processing routine is terminated while the step counter CNTS is "3", the second braking reduction instruction processing is continued. On the other hand, when this processing routine is terminated while the step counter CNTS is "4", the second braking reduction instruction processing is terminated.

Next, with reference to FIG. 10, the second braking increase instruction process and the first drive decrease instruction process in step S38 will be described.
In this processing routine, the braking increase instruction unit 43 executes the second braking increase instruction process. In the first step S111 in the second braking increase instruction process, the sum of the above-mentioned second braking force previous value BP2a and the second braking increase amount ΔBP21 is calculated as the latest second instruction braking force BPTr2. A positive value is set as the second braking increase amount ΔBP21. Subsequently, in step S112, it is determined whether or not the second indicated braking force BPTr2 calculated in step S111 is equal to or greater than the second target braking force BPS2. As the second target braking force BPS2, for example, the braking force of the second wheel at the start of attitude control, or a value slightly larger than the braking force is set. Alternatively, as the second target braking force BPS2, a braking force according to the braking operation by the driver at the present time, a braking force set by the control device for automatic braking, or the like may be set. When the second indicated braking force BPTr2 is equal to or greater than the second target braking force BPS2 (S112: YES), the process proceeds to the next step S113. In step S113, the second target braking force BPS2 is set as the second indicated braking force BPTr2, and the step counter CNTS is incremented by "1". That is, the step counter CNTS becomes "5". Then, the process proceeds to the next step S114.

On the other hand, in step S112, when the second indicated braking force BPTr2 is less than the second target braking force BPS2 (NO), the process shifts to the next step S114. That is, the step counter CNTS is held at "4".

In step S114, an output process for outputting the first indicated braking force BPTr1 and the second indicated braking force BPTr2 to the braking device 20 is executed. While the execution of this processing routine is repeated, the second indicated braking force BPTr2 output to the braking device 20 continues to increase. Therefore, outputting the second instruction braking force BPTr2 to the braking device 20 through the execution of this processing routine corresponds to instructing the braking device 20 to increase the braking force of the second wheel. Then, the process to be executed is shifted from the second braking increase instruction process to the first drive decrease instruction process.

When the first indicated braking force BPTr1 and the second indicated braking force BPTr2 are input by executing the output process, the braking control unit 22 follows the first indicated braking force BPTr1 with the braking force of the first wheel. , The braking actuator 21 is controlled so that the braking force of the second wheel follows the second indicated braking force BPTr2. In the second braking increase instruction processing, the first instruction braking force BPTr1 is held, while the second instruction braking force BPTr2 is increased. Therefore, by inputting an instruction based on the execution of the second braking increase instruction process to the braking control unit 22, the braking force of the first wheel is maintained and the speed corresponding to the second braking increase amount ΔBP21 is increased. The braking force of the two wheels can be increased.

The first drive reduction instruction process is executed by the drive reduction instruction unit 44. In the first drive reduction instruction process, in step S115, it is determined whether or not the sum of the first braking force previous value BP1a and the second indicated braking force BPTr2 is equal to or greater than the stop holding force Fh. If the sum is less than the stop holding force Fh, the vehicle 10 may start unless the driving force DP of the vehicle 10 is reduced. When the sum is less than the stop holding force Fh (S115: NO), the process proceeds to the next step S116. In step S116, the value obtained by subtracting the sum from the stop holding force Fh is calculated as the first instruction driving force DPTr1. When this processing routine is repeatedly executed, the second indicated braking force BPTr2 is increased, so that the sum of the first braking force previous value BP1a and the second indicated braking force BPTr2 becomes large. As a result, the first instruction driving force DPTr1 is reduced at a speed corresponding to the increasing speed of the second instruction braking force BPTr2. Then, the process proceeds to step S118, which will be described later.

On the other hand, in step S115, when the sum of the first braking force previous value BP1a and the second indicated braking force BPTr2 is equal to or greater than the stop holding force Fh (YES), the process proceeds to the next step S117. In step S117, "0 (zero)" is set as the first instruction driving force DPTr1. Then, the process proceeds to the next step S118.

In step S118, an output process for outputting the first instruction driving force DPTr1 to the driving device 30 is executed. While the execution of this processing routine is repeated, the first instruction driving force DPTr1 output to the driving device 30 continues to decrease. Therefore, outputting the first instruction driving force DPTr1 to the driving device 30 through the execution of this processing routine corresponds to instructing the driving device 30 to reduce the driving force DP of the vehicle 10.

When the first instruction driving force DPTr1 is input by executing the output processing, the drive control unit 32 controls the power unit 31 so that the driving force DP of the vehicle 10 follows the first instruction driving force DPTr1. In the first drive reduction instruction process, the first instruction drive force DPTr1 is reduced. Therefore, the driving force DP of the vehicle 10 can be reduced by inputting an instruction based on the execution of the first drive reduction instruction process to the drive control unit 32.

When the output process is executed, the process proceeds to the next step S119. In step S119, similarly to step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, and the current second indicated braking force BPTr2 is set as the second braking force previous value BP2a. , The current first indicated driving force DPTr1 is set as the first driving force previous value DP1a. After that, this processing routine is terminated.

When this processing routine is terminated while the step counter CNTS is "4", the second braking increase instruction processing and the first drive decrease instruction processing are continued, respectively. On the other hand, when this processing routine is terminated while the step counter CNTS is "5", the second braking increase instruction processing and the first drive decrease instruction processing are terminated, respectively.

Next, with reference to FIG. 11, the first braking increase instruction process and the second drive decrease instruction process in step S39 will be described.
In this processing routine, the braking increase instruction unit 43 executes the first braking increase instruction process. In the first step S131 in the first braking increase instruction process, the sum of the first braking force previous value BP1a and the first braking increase amount ΔBP11 is calculated as the first instruction braking force BPTr1. A positive value is set as the first braking increase amount ΔBP11. Subsequently, in step S132, it is determined whether or not the first indicated braking force BPTr1 calculated in step S131 is equal to or greater than the first target braking force BPS1. As the first target braking force BPS1, for example, the braking force of the first wheel at the start of attitude control, or a value slightly larger than the braking force is set. Alternatively, as the first target braking force BPS1, a braking force according to the current braking operation by the driver, a braking force set by the control device for automatic braking, or the like may be set. When the first indicated braking force BPTr1 is equal to or greater than the first target braking force BPS1 (S132: YES), the process proceeds to the next step S133. On the other hand, when the first indicated braking force BPTr1 is less than the first target braking force BPS1 (S132: NO), the process shifts to step S134 described later.

In step S133, the first target braking force BPS1 is set as the first indicated braking force BPTr1, and the step counter CNTS is reset to "0 (zero)". In addition, the control completion flag FLG2 is set to ON. That is, on is set to any of the flags FLG1 and FLG2. Then, the process proceeds to the next step S134.

In step S134, an output process for outputting the first indicated braking force BPTr1 and the second indicated braking force BPTr2 to the braking device 20 is executed. While the execution of this processing routine is repeated, the first indicated braking force BPTr1 output to the braking device 20 continues to increase. Therefore, outputting the first instruction braking force BPTr1 to the braking device 20 through the execution of this processing routine corresponds to instructing the braking device 20 to increase the braking force of the first wheel. Then, the process to be executed is shifted from the first braking increase instruction process to the second drive decrease instruction process.

When the first indicated braking force BPTr1 and the second indicated braking force BPTr2 are input by executing the output process, the braking control unit 22 follows the first indicated braking force BPTr1 with the braking force of the first wheel. , The braking actuator 21 is controlled so that the braking force of the second wheel follows the second indicated braking force BPTr2. In the first braking increase instruction processing, the second instruction braking force BPTr2 is held, while the first instruction braking force BPTr1 is increased. Therefore, by inputting an instruction based on the execution of the first braking increase instruction process to the braking control unit 22, the braking force of the second wheel is maintained, and the speed corresponding to the first braking increase amount ΔBP11 is increased. The braking force of one wheel can be increased.

The second drive reduction instruction process is executed by the drive reduction instruction unit 44. In the first step S135 in the second drive reduction instruction process, it is determined whether or not the sum of the second braking force previous value BP2a and the first indicated braking force BPTr1 is equal to or greater than the stop holding force Fh. If the sum is less than the stop holding force Fh, the vehicle 10 may start unless the driving force DP of the vehicle 10 is reduced. When the sum is less than the stop holding force Fh (S135: NO), the process proceeds to the next step S136. In step S136, the value obtained by subtracting the sum from the stop holding force Fh is calculated as the first instruction driving force DPTr1. When this processing routine is repeatedly executed, the first indicated braking force BPTr1 is increased, so that the sum of the second braking force previous value BP2a and the first indicated braking force BPTr1 becomes large. As a result, the first instruction driving force DPTr1 is reduced at a speed corresponding to the increasing speed of the first instruction braking force BPTr1. Then, the process proceeds to step S138, which will be described later.

On the other hand, in step S135, when the sum of the second braking force previous value BP2a and the first indicated braking force BPTr1 is equal to or greater than the stop holding force Fh (YES), the process proceeds to the next step S137. In step S137, "0 (zero)" is set as the first instruction driving force DPTr1. Then, the process proceeds to the next step S138.

In step S138, an output process for outputting the first instruction driving force DPTr1 to the driving device 30 is executed. While the execution of this processing routine is repeated, the first instruction driving force DPTr1 output to the driving device 30 continues to decrease. Therefore, outputting the first instruction driving force DPTr1 to the driving device 30 through the execution of this processing routine corresponds to instructing the driving device 30 to reduce the driving force DP of the vehicle 10.

When the first instruction driving force DPTr1 is input by executing the output processing, the drive control unit 32 controls the power unit 31 so that the driving force DP of the vehicle 10 follows the first instruction driving force DPTr1. In the second drive reduction instruction process, the first instruction drive force DPTr1 is reduced. Therefore, the driving force DP of the vehicle 10 can be reduced by inputting an instruction based on the execution of the second drive reduction instruction process to the drive control unit 32.

When the output process is executed, the process proceeds to the next step S139. In step S139, similarly to step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, and the current second indicated braking force BPTr2 is set as the second braking force previous value BP2a. , The current first indicated driving force DPTr1 is set as the first driving force previous value DP1a. After that, this processing routine is terminated.

When this processing routine is terminated with the control completion flag FLG2 set to off, the first braking increase instruction processing and the second drive decrease instruction processing are continued, respectively. On the other hand, when this processing routine is terminated with the flags FLG1 and FLG2 set to ON, the first braking increase instruction processing and the second drive decrease instruction processing are terminated, respectively.

Next, the operation and effect of the present embodiment will be described with reference to FIG. As a premise, it is assumed that the vehicle 10 is located on the uphill road.
As shown in FIGS. 12 (a), (b), (c), (d), (e), and (f), the braking force applied to the vehicle at the timing T11 while the vehicle 10 is traveling on the uphill road. BP is given. At this time, during the period from timing T11 to timing T12, the front wheel braking force BPF, which is the braking force of the first wheel, is increased, and the rear wheel braking force BPR, which is the braking force of the second wheel, is increased. Then, after the timing T12, the front wheel braking force BPF and the rear wheel braking force BPR are held, respectively.

When the braking force is applied to the front wheels 11 which are the first wheels in this way, the first contact patch friction force FF1 acts on the slope side behind the vehicle 10 on the contact patch with the road surface on the front wheels 11. The first contact patch friction force FF1 increases as the front wheel braking force BPF increases. Similarly, when a braking force is applied to the rear wheels 12 which are the second wheels, the second contact patch friction force FF2 acts on the slope side behind the vehicle 10 on the contact patch with the road surface on the rear wheels 12. .. The second contact patch friction force FF2 increases as the rear wheel braking force BPR increases. Then, when the vehicle 10 is stopped at the timing T13 by applying the braking force BP, the positive and negative of the first ground contact surface friction force FF1 and the second ground contact surface friction force FF2 are reversed. That is, the first contact patch friction force FF1 acts on the slope upper side in front of the vehicle 10 on the contact patch with the road surface on the front wheels 11, and the second contact patch friction force FF2 acts on the contact patch with the road surface on the rear wheels 12. It acts on the upper side of the slope, which is in front of the vehicle 10.

Further, when the vehicle 10 is decelerating due to the application of the braking force BP, the vehicle 10 pitches toward the nose dive side. Then, while the front wheel suspension 13F contracts, the rear wheel suspension 13R expands. At the same time, due to the geometry of each suspension 13F and 13R, an anti-dive force corresponding to the front wheel braking force BPF is generated in the front part of the vehicle body 16, and an antilift force corresponding to the rear wheel braking force BPR is generated in the rear part of the vehicle body 16. appear. As a result, the position of the front wheels 11 in the vehicle front-rear direction X changes from the reference position of the front wheels 11, and the position of the rear wheels 12 in the vehicle front-rear direction X changes from the reference position of the rear wheels 12. As a result, the wheelbase WBL of the vehicle 10 changes from the reference wheelbase WBLB.

In the example shown in FIG. 12, even if the vehicle 10 stops at the timing T13, the front wheel braking force BPF and the rear wheel braking force BPR are maintained. As a result, the wheels 11 and 12 are in a locked state in which rotation is restricted, and the positions of the suspensions 13F and 13R in the vertical direction are maintained in a displaced state. As a result, the position of the front wheels 11 in the vehicle front-rear direction X is different from the reference position of the front wheels 11, and the position of the rear wheels 12 in the vehicle front-rear direction X is different from the reference position of the rear wheels 12. That is, the wheelbase WBL of the vehicle 10 continues to be different from the reference wheelbase WBLB.

In the present embodiment, the attitude control is started from the timing T14 when the vehicle 10 is stopped. When the attitude control is performed, the front wheel braking force BPF and the rear wheel braking force BPR are reduced. Further, the driving force DP of the vehicle is increased so that the stop of the vehicle 10 is maintained even if the braking force BP of the vehicle is reduced in this way. When the front wheel braking force BPF is reduced by the implementation of attitude control, the front wheels 11 are allowed to rotate, so that the position of the front wheels 11 in the vehicle front-rear direction X can be returned to the reference position of the front wheels 11, that is, the front wheel suspension. The state of 13F can be restored. Further, when the rear wheel braking force BPR is reduced by the implementation of the attitude control, the rotation of the rear wheels 12 is allowed, so that the position of the rear wheels 12 in the vehicle front-rear direction X can be returned to the reference position of the rear wheels 12. That is, the state of the rear wheel suspension 13R can be restored. That is, the wheelbase WBL of the vehicle 10 can be returned to the reference wheelbase WBLB while the vehicle 10 is stopped. Therefore, when the braking of the vehicle 10 is subsequently released in order to start the vehicle 10, it is possible to suppress a sudden change in the posture of the vehicle 10 due to a change in the wheelbase WBL. Therefore, it is possible to prevent the occupants of the vehicle 10 from being uncomfortable when the vehicle starts.

Specifically, from the timing T14, the first braking reduction instruction process of the attitude control is started. When the first braking reduction instruction processing is executed, the first instruction braking force BPTr1 is reduced, so that the front wheel braking force BPF is reduced by driving the braking actuator 21. Since the first instruction braking force BPTr1 becomes "0" at the timing T16, the first braking reduction instruction process is completed. In the present embodiment, when the front wheel braking force BPF is reduced within the period from timing T14 to timing T16, the front wheels 11 are allowed to rotate, and the position of the front wheels 11 in the vehicle front-rear direction X is the reference position of the front wheels 11. Return to.

During the execution of the first braking reduction instruction processing, the braking force BP of the vehicle is reduced. Then, at the timing T15 during the execution of the first braking reduction instruction processing, the sum of the first instruction braking force BPTr1 and the second braking force previous value BP2a becomes less than the stop holding force Fh, so that the first drive of attitude control is increased. By executing the instruction processing, the increase of the first instruction driving force DPTr1 is started. Then, the driving force DP of the vehicle 10 is increased by driving the power unit 31 in accordance with the increase of the first indicated driving force DPTr1. That is, by executing the first drive increase instruction process during the execution of the first brake decrease instruction process, the front wheel braking force BPF is replaced with the drive force DP of the vehicle 10. As a result, even if the braking force BP of the vehicle 10 is reduced due to the execution of the first braking reduction instruction process, the state in which the vehicle 10 is stopped can be maintained.

When the first braking decrease instruction process is completed at the timing T16, the first drive increase instruction process is ended, and the second drive increase instruction process is started as the drive increase instruction process. Therefore, since the first instruction driving force DPTr1 is increased even after the timing T16, the driving force DP of the vehicle 10 is increased. Then, since the first instruction driving force DPTr1 reaches the stop holding force Fh at the timing T17, the second drive increase instruction process is completed. That is, the increase in the driving force DP of the vehicle 10 is completed. At this point, even if the braking of the vehicle 10 is released, the stopping of the vehicle 10 can be maintained by the driving force DP.

Then, from the timing T17, the second braking reduction instruction process of the attitude control is started while the first instruction driving force DPTr1, that is, the driving force DP of the vehicle 10 is held. When the second braking reduction instruction process is executed, the second instruction braking force BPTr2 is reduced, so that the rear wheel braking force BPR is reduced by driving the braking actuator 21. Since the second instruction braking force BPTr2 becomes "0" at the timing T18, the second braking reduction instruction process is completed. In the present embodiment, when the rear wheel braking force BPR is reduced within the period from timing T17 to timing T18, the rear wheels 12 are allowed to rotate, and the position of the rear wheels 12 in the vehicle front-rear direction X is the rear wheels. Return to the reference position of 12. As a result, the wheelbase WBL of the vehicle returns to the reference wheelbase WBLB within the period from timing T17 to timing T18.

After the timing T16 when the braking of the front wheels 11 is released, the driving force DP of the vehicle 10 is increased, so that the propulsive force for moving the vehicle 10 forward is applied to the vehicle 10. Then, the sum of the driving force DP and the rear wheel braking force BPR becomes larger than the stop holding force Fh. When the front wheel braking force BPF is larger than "0 (zero)", it can be said that the driving force DP is offset by the front wheel braking force BPF. Therefore, it can be said that the sum of the surplus driving force, which is the value obtained by subtracting the front wheel braking force BPF from the driving force DP, and the rear wheel braking force BPR is larger than the stop holding force Fh. In this case, since the front wheel braking force BPF is "0 (zero)", the surplus driving force is equal to the driving force DP. Then, as the driving force DP, that is, the surplus driving force increases and the propulsive force increases, the second contact patch friction force FF2 acting on the rear wheels 12 gradually decreases. This is because the gravity that tries to move the vehicle 10 to the slope side is supported by the above-mentioned propulsive force. Then, when the first indicated driving force DPTr1 becomes equal to the stop holding force Fh, that is, when the surplus driving force becomes equal to the stop holding force Fh, the second contact patch friction force FF2 becomes substantially "0 (zero)".

Here, when the second contact patch friction force FF2 immediately before the vehicle 10 stops is set to the second contact patch acting force reference value FF2B, the position of the rear wheel 12 in the vehicle front-rear direction X becomes the reference position of the rear wheel 12. The larger the deviation ΔFF2 between the second ground contact surface friction force FF2 and the second ground contact surface acting force reference value FF2B when returning, the more rear when the rear wheel 12 shifts from the locked state to the rear wheel 12 rotating state. The wheel suspension 13R moves suddenly. That is, the displacement speed of the rear wheels 12 increases when the position of the rear wheels 12 in the vehicle front-rear direction X returns to the reference position of the rear wheels 12. At this time, vibration or sound may be generated due to the sudden movement of the rear wheel suspension 13R.

In this respect, in the present embodiment, the second contact patch friction force FF2 is set to be substantially "0 (zero)" by increasing the driving force DP, and then the position of the rear wheel 12 in the vehicle front-rear direction X is returned to the reference position of the rear wheel 12. be able to. When the rear wheels 12 are rotated in this way, the frictional force corresponding to the rear wheel braking force BPR changes from static friction to dynamic friction when the rear wheels 12 are changed from the locked state to the rotating state of the rear wheels 12. For example, when the braking mechanism provided on the rear wheel 12 is a disc type, the friction between the disc and the friction material changes from static friction to dynamic friction. Therefore, even if the pressing force, which is the force for pressing the friction material against the disc, is smoothly reduced, the braking force suddenly decreases at the moment when the static friction changes to the dynamic friction. At this time, the smaller the deviation ΔFF2, the smaller the force that displaces the rear wheel 12 to the reference position of the rear wheel 12 at the time when the rear wheel 12 shifts to the rotating state. As a result, as compared with the case where the deviation ΔFF2 is large, the rear wheel 12 shifts from the locked state to the rear wheel 12 rotating state, and the frictional force corresponding to the rear wheel braking force BPR changes from static friction to dynamic friction. It is possible to suppress the sudden movement of the rear wheel suspension 13R at the time.

During braking, the rear wheel suspension 13R is longer than in the above stop reference state, so the position of the rear wheel 12 in the vehicle front-rear direction X during braking is relative to the reference position of the rear wheel 12. It is located on the side that shortens the wheelbase WBL. Therefore, after braking, the position of the rear wheel 12 in the vehicle front-rear direction X is on the way back from the position where the wheelbase WBL is shortened with respect to the reference position during braking to the reference position of the rear wheel 12. Therefore, a force for moving the rear wheel 12 to the rear of the vehicle acts on the rear wheel 12. Further, when the vehicle 10 is stopped on an uphill road, a second contact patch friction force FF2 acts on the contact patch of the rear wheels 12 with the road surface on the slope side behind the vehicle. In this case, the second ground contact surface friction force FF2 acts on the rear wheels 12 as a force for moving the rear wheels 12 to the rear of the vehicle. That is, the force for moving the rear wheel 12 to the rear of the vehicle becomes even greater. Therefore, by reducing the frictional force FF2 on the second contact patch by increasing the driving force DP, the rear wheels 12 are rotated in the direction of moving the rear wheels 12 to the rear of the vehicle at the time when the rear wheels 12 shift to the rotating state. The force to make it can be reduced. As a result, as compared with the case where the second ground contact surface frictional force FF2 to the slope side behind the vehicle 10 is large, the rear wheel 12 is shifted from the locked state to the rear wheel 12 rotating state, and the rear wheel 12 is used. The suspension 13R can suppress a sudden movement of the rear wheel suspension 13R when the frictional force corresponding to the rear wheel braking force BPR changes from static friction to dynamic friction.

By appropriately changing the second ground contact surface friction force FF2 by the driving force DP as described above, it is possible to gently change the posture of the vehicle 10 due to the change in the wheelbase WBL. Further, it is possible to suppress the generation of vibration and sound caused by the movement of the rear wheel suspension 13R.

Further, in the present embodiment, the timing of returning the position of the rear wheel 12 in the vehicle front-rear direction X to the reference position of the rear wheel 12 is shifted from the timing of returning the position of the front wheel 11 in the vehicle front-rear direction X to the reference position of the front wheel 11. There is. As a result, it is possible to suppress an increase in the rate of change of the wheelbase WBL as compared with the case where the front wheels 11 and the rear wheels 12 are returned to the reference positions almost at the same time. As a result, it is possible to make it difficult for the occupants of the vehicle 10 to notice the change in the posture of the vehicle 10 due to the change in the wheelbase WBL while the vehicle 10 is stopped.

When the second braking reduction instruction processing, that is, the attitude control is completed in this way, the front wheel braking force BPF and the rear wheel braking force BPR are increased by driving the braking actuator 21 based on the execution of the braking increase control. Further, the driving force DP of the vehicle 10 is reduced by driving the power unit 31 based on the execution of the driving increase control. As a result, it is possible to suppress the continuous application of the driving force DP to the vehicle 10 while the vehicle 10 is stopped, and thus it is possible to suppress a decrease in the energy efficiency of the vehicle.

In the present embodiment, the second braking increase instruction process and the first drive decrease instruction process are started from the timing T18. When the second braking increase instruction process is executed, the second instruction braking force BPTr2 is increased, so that the rear wheel braking force BPR is increased by driving the braking actuator 21. Since the second instruction braking force BPTr2 reaches the second target braking force BPS2 at the timing T19, the second braking increase instruction process is terminated. That is, after the timing T19, the rear wheel braking force BPR is maintained.

Further, when the first drive reduction instruction process is executed, the first instruction drive force DPTr1 is reduced, so that the drive force DP of the vehicle 10 is reduced by driving the power unit 31. The decreasing speed of the driving force DP at this time corresponds to the increasing speed of the rear wheel braking force BPR. That is, in the period from the timing T18 to the timing T19, the driving force DP is replaced with the rear wheel braking force BPR. Then, at the timing T19, the first drive reduction instruction process is completed.

Then, the first braking increase instruction process and the second drive decrease instruction process are started from the timing T19. When the first braking increase instruction process is executed, the first instruction braking force BPTr1 is increased, so that the front wheel braking force BPF is increased by driving the braking actuator 21. Since the first indicated braking force BPTr1 reaches the first target braking force BPS1 at the timing T111, the first braking increase instruction process is terminated. That is, after the timing T111, the front wheel braking force BPF is maintained.

Further, when the second drive reduction instruction process is executed, the first instruction drive force DPTr1 is reduced, so that the drive force DP of the vehicle 10 is reduced by driving the power unit 31. Then, at the timing T110, the first instruction driving force DPTr1 becomes “0 (zero)”. The decreasing speed of the driving force DP at this time corresponds to the increasing speed of the front wheel braking force BPF. That is, in the period from the timing T19 to the timing T110, the driving force DP is replaced with the front wheel braking force BPF.

Here, a comparative example in which the front wheel braking force BPF and the rear wheel braking force BPR are increased at the same time will be considered. In this comparative example, when the driving force DP of the vehicle 10 is replaced with the braking force BP of the vehicle 10, the reduction speed of the driving force DP becomes high. In this case, the occupant of the vehicle 10 can easily feel the sound and vibration generated from the power unit 31 due to the decrease in the driving force DP.

In this respect, in the present embodiment, the increase in the rear wheel braking force BPR and the increase in the front wheel braking force BPF are time-shifted. Therefore, the reduction speed of the driving force DP can be made lower than in the case of the above comparative example. As a result, it becomes difficult for the occupants of the vehicle 10 to feel the sound and vibration generated from the power unit 31 due to the decrease in the driving force DP.

Further, in the present embodiment, the driving force DP of the vehicle 10 is reduced at the same time as the braking force BP of the vehicle 10 is increased. As a result, the energy of the vehicle can be started earlier than the case where the reduction of the driving force DP is started after the increase of the braking force BP due to the implementation of the braking increase control is completed. Efficiency can be increased.

The example shown in FIG. 12 is an example in which the rear wheel braking force BPR before the start of attitude control is smaller than the stop holding force Fh. Depending on the road surface gradient θ, the rear wheel braking force BPR before the start of attitude control may be larger than the stop holding force Fh. FIG. 13 shows a timing chart when the rear wheel braking force BPR before the start of attitude control is larger than the stop holding force Fh.

As shown in FIGS. 13 (a), (b), (c), (d), (e), and (f), the vehicle 10 is stopped by applying braking force to the front wheels 11 and the rear wheels 12. Then, the attitude control first braking reduction instruction process is started from the timing T41. The first braking reduction instruction process is executed until the timing T42. Therefore, when the front wheel braking force BPF is reduced within the period from the timing T41 to the timing T42, the rotation of the front wheels 11 is allowed, and the position of the front wheels 11 in the vehicle front-rear direction X returns to the reference position of the front wheels 11. In addition, the state of the front wheel suspension 13F returns to the original state.

In the example shown in FIG. 13, the stop holding force Fh is smaller than the rear wheel braking force BPR. Therefore, during the execution of the first braking reduction instruction processing, the execution of the first drive increase instruction processing does not start the increase of the first instruction braking force BPTr1. Therefore, the first instruction driving force DPTr1 is increased by executing the second drive increase instruction process started from the timing T42 at which the first braking decrease instruction process is completed. When the first instruction driving force DPTr1 reaches the stop holding force Fh at the timing T43, the second drive increase instruction process is terminated and the second braking decrease instruction process is started. Since the processing flow after the timing T43 is the same as that of the example shown in FIG. 12, the description thereof will be omitted.

(Second Embodiment)
Next, a second embodiment of the vehicle control device will be described with reference to FIGS. 14 and 15. In the second embodiment, the contents of some of the various processes to be executed are different from those in the first embodiment. Therefore, in the following description, the parts that are different from the first embodiment will be mainly described, and the same or corresponding member configurations as those in the first embodiment are designated by the same reference numerals and duplicate description is omitted. It shall be.

The second drive increase instruction process executed in this embodiment will be described with reference to FIG. This processing routine is executed by the attitude control unit 42.
In this processing routine, in step S151, it is determined whether or not the current second indicated braking force BPTr2 is less than the second pre-stop braking force BP2b. The second pre-stop braking force BP2b is set in step S12 of the processing routine described with reference to FIG. When the second indicated braking force BPTr2 is less than the second pre-stop braking force BP2b (S151: YES), the process proceeds to the next step S152. In step S152, the second indicated braking force BPTr2 is set as the raising target force BP2t. Then, the process proceeds to step S154, which will be described later.

On the other hand, in step S151, when the second indicated braking force BPTr2 is equal to or greater than the second stop pre-stop braking force BP2b (NO), the process shifts to the next step S153. In step S153, the second stop pre-stop braking force BP2b is set as the raising target force BP2t. Then, the process proceeds to the next step S154.

In step S154, the sum of the first driving force previous value DP1a and the first driving increase amount ΔDP1 is calculated as the latest first indicated driving force DPTr1 in the same manner as in step S71. Subsequently, in step S155, it is determined whether or not the first instruction driving force DPTr1 calculated in step S154 is equal to or greater than the sum of the above-mentioned stop holding force Fh and the raising target force BP2t. When the first indicated driving force DPTr1 is equal to or greater than the sum, the vehicle 10 will start if the driving force DP of the vehicle 10 is further increased. Therefore, when the first instruction driving force DPTr1 is equal to or greater than the sum (S155: YES), the process proceeds to the next step S156. In step S156, the sum of the stop holding force Fh and the raising target force BP2t is set as the first instruction driving force DPTr1, and the step counter CNTS is incremented by "1". That is, the step counter CNTS becomes "3". Then, the process proceeds to the next step S157.

On the other hand, in step S155, when the first instruction driving force DPTr1 is smaller than the sum of the stop holding force Fh and the raising target force BP2t (NO), the process proceeds to the next step S157. That is, the step counter CNTS is held at "2".

In step S157, an output process for outputting the first indicated driving force DPTr1 to the driving device 30 is executed in the same manner as in step S74. While the execution of this processing routine is repeated, the first instruction driving force DPTr1 output to the driving device 30 continues to increase. Therefore, outputting the first instruction driving force DPTr1 to the driving device 30 through the execution of this processing routine corresponds to instructing the driving device 30 to increase the driving force DP of the vehicle 10. Then, in the next step S158, similarly to the above step S22, the current first indicated braking force BPTr1 is set as the first braking force previous value BP1a, and the current second indicated braking force BPTr2 is the second braking force previous value. It is set as BP2a, and the current first indicated driving force DPTr1 is set as the first driving force previous value DP1a. After that, this processing routine is terminated.

Next, the first drive reduction instruction process executed in the present embodiment will be described. In the first embodiment, the first drive decrease instruction process is started at the same time as the second brake increase instruction process, while in the present embodiment, the first drive decrease instruction process is caused by the execution of the second drive increase instruction process. It is started before the start of the second braking reduction instruction process after the completion of the increase in the driving force DP of the vehicle 10. Specifically, the first drive decrease instruction process is started when the increase in the driving force DP of the vehicle 10 due to the execution of the second drive increase instruction process is completed.

In the first drive reduction instruction process executed in the present embodiment, the first instruction drive force DPTr1 is updated so that the first instruction drive force DPTr1 is reduced at a preset speed. The first drive phenomenon instruction process is continued even after the start of the second braking increase instruction process. Then, when the second braking increase instruction process is completed, the first drive decrease instruction process is also completed.

Next, with reference to FIG. 15, a part of the operation and effect of the present embodiment that is different from that of the first embodiment will be mainly described.
As shown in FIGS. 15 (a), (b), (c), (d), (e), and (f), the vehicle 10 stops at the timing T21 due to the application of braking force to the front wheels 11 and the rear wheels 12. To do. During the period from the timing T21 to the timing T22 when the attitude control is started, the front wheel braking force BPF and the rear wheel braking force BPR are maintained, respectively. Therefore, the position of the front wheels 11 in the vehicle front-rear direction X is different from the reference position of the front wheels 11, and the position of the rear wheels 12 in the vehicle front-rear direction X is different from the reference position of the rear wheels 12. That is, the wheelbase WBL of the vehicle 10 continues to be different from the reference wheelbase WBLB.

Then, the first braking reduction instruction process for attitude control is started from the timing T22. The first braking reduction instruction process is executed until timing T24. Therefore, when the front wheel braking force BPF is reduced within the period from the timing T22 to the timing T24, the rotation of the front wheels 11 is allowed, and the position of the front wheels 11 in the vehicle front-rear direction X returns to the reference position of the front wheels 11. In addition, the state of the front wheel suspension 13F returns to the original state.

At the timing T23 during execution of the first braking decrease instruction process, the sum of the first instruction braking force BPTr1 and the second braking force previous value BP2a becomes less than the stop holding force Fh, so that the first drive increase instruction process of attitude control By executing the above, the increase of the first indicated braking force BPTr1 is started. Then, since the first braking decrease instruction process is terminated at the timing T24, the drive increase instruction process is switched from the first drive increase instruction process to the second drive increase instruction process.

The second drive increase instruction process is continued even after the timing T25 when the first instruction drive force DPTr1 reaches the stop holding force Fh. Then, at the timing T26, the first instruction driving force DPTr1 reaches the sum of the stop holding force Fh and the raising target force BP2t, so that the second drive increase instruction process is completed. Therefore, in the present embodiment, the driving force DP of the vehicle 10 can be increased to the sum of the stop holding force Fh and the raising target force BP2t, or to the vicinity of the sum by executing the second drive increasing instruction process. The sum of the stop holding force Fh and the raising target force BP2t is an upper limit of the driving force DP capable of maintaining the stop of the vehicle 10 under the current situation where the braking force BP is held, or a value near the upper limit.

By making the driving force DP of the vehicle 10 larger than the stop holding force Fh, the second contact patch friction force FF2 acts on the slope side with respect to the contact patch of the rear wheel 12 with the road surface. Then, at the timing T26 when the driving force DP becomes equal to the sum of the stop holding force Fh and the raising target force BP2t, the second contact patch friction force FF2 is the second contact patch friction force immediately before the timing T21 when the vehicle 10 stops. It is almost equal to the second contact patch acting force reference value FF2B which is FF2.

In the present embodiment, the second contact patch friction force FF2 is made substantially equal to the second contact patch acting force reference value FF2B, and then the second instruction braking force BPTr2, that is, the rear wheel system is executed by executing the second braking reduction instruction process. Power BPR is reduced. That is, when the above deviation ΔFF2 is a value close to “0 (zero)”, the position of the rear wheel 12 in the vehicle front-rear direction X is returned to the reference position, and the state of the rear wheel suspension 13R is the basis. Be returned. At this time, since the position of the rear wheel 12 in the vehicle front-rear direction X can be displaced more slowly, the posture of the vehicle 10 can be changed more slowly due to the change in the wheelbase WBL. Further, since the effect of suppressing the sudden movement of the rear wheel suspension 13R can be enhanced, the effect of suppressing the generation of vibration and sound caused by the movement of the rear wheel suspension 13R can be enhanced.

Since the rear wheel braking force BPR is reduced from the timing T26 due to the execution of the second braking reduction instruction processing, the first instruction driving force DPTr1, that is, the vehicle is reduced in accordance with the decrease in the rear wheel braking force BPR after the timing T26. The driving force DP of 10 is reduced. Then, at the timing T27 when the second braking reduction instruction process is completed, the first instruction driving force DPTr1 reaches the stop holding force Fh. Therefore, the vehicle 10 can be kept stopped even during the execution of the second braking reduction instruction process.

(Third Embodiment)
Next, a third embodiment of the vehicle control device will be described with reference to FIG. In the second embodiment, the start timing of various processes and the like are different from those in the second embodiment. Therefore, in the following description, the parts that are different from the first embodiment and the second embodiment will be mainly described, and the same or corresponding member configurations as those of the first embodiment and the second embodiment will be the same. It shall be coded and duplicate description shall be omitted.

Among the first drive increase instruction processes executed in the present embodiment, the differences from the first drive increase instruction process executed in the second embodiment will be mainly described.
In the first drive increase instruction process executed in the present embodiment, in step S55 shown in FIG. 7, the sum of the first instruction braking force BPTr1 and the second braking force previous value BP2a is the stop holding force Fh and the first correction. It is determined whether or not it is equal to or greater than the sum of the quantity Fα. Although a value corresponding to the road surface gradient θ is set as the stop holding force Fh, the road surface gradient θ may include a derivation error. When the road surface gradient θ is smaller than the actual road surface gradient, the driving force DP of the vehicle 10 is increased after the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a becomes less than the stop holding force Fh. When starting, there is a possibility that the vehicle 10 may slide down due to a decrease in the braking force of the first wheel due to the execution of the first braking reduction instruction process. Therefore, as the first correction amount Fα, a value corresponding to the derivation error of the road surface gradient θ or a value larger than the value is set.

Then, when the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a is equal to or greater than the sum of the stop holding force Fh and the first correction amount Fα (S55: YES), the process proceeds to step S56. Then, "0 (zero)" is set as the first indicated driving force DPTr1. That is, the increase in the driving force DP has not yet started. On the other hand, when the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a is less than the sum of the stop holding force Fh and the first correction amount Fα (S55: NO), the process proceeds to step S57. Will be done. In step S57, the value obtained by subtracting the sum of the stop holding force Fh and the first correction amount Fα from the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a is calculated as the first indicated driving force DPTr1. To.

Since the content of each process after step S58 is the same as that of the first embodiment and the second embodiment, the description thereof will be omitted.
Next, among the second drive increase instruction processes executed in the present embodiment, the differences from the second drive increase instruction process executed in the second embodiment will be mainly described.

In the second drive increase instruction process executed in the present embodiment, in step S151 shown in FIG. 14, it is determined whether or not the current second instruction braking force BPTr2 is less than the second pre-stop braking force BP2b. Will be. When the second indicated braking force BPTr2 is less than the second pre-stop braking force BP2b (S151: YES), the process proceeds to the next step S152. In step S152, the value obtained by subtracting the second correction amount Fβ from the second indicated braking force BPTr2 is set as the raising target force BP2t. Then, the process proceeds to step S154, which will be described later. On the other hand, in step S151, when the second indicated braking force BPTr2 is equal to or greater than the second stop pre-stop braking force BP2b (NO), the process shifts to the next step S153. In step S153, the value obtained by subtracting the second correction amount Fβ from the braking force BP2b before the second stop is set as the raising target force BP2t. Then, the process proceeds to the next step S154.

As described above, the stop holding force Fh may include a derivation error component of the road surface gradient θ. In addition, there is a possibility that there is a discrepancy between the second indicated braking force BPTr2 and the actual rear wheel braking force BPR. If the raising target force BP2t is not set in consideration of such an error component, the stop of the vehicle 10 may not be maintained when the first indicated driving force DPTr1 is increased to the sum of the stop holding force Fh and the raising target force BP2t. There is. Therefore, the second correction amount Fβ is set in consideration of the derivation error of the stop holding force Fh and the deviation between the second indicated braking force BPTr2 and the actual rear wheel braking force BPR.

Since the content of each process after step S154 is the same as that of the second embodiment, the description thereof will be omitted.
Next, the first braking increase instruction process executed in the present embodiment will be described.

The first braking increase instruction process executed in the present embodiment is started when the second drive increase instruction process is completed. That is, the first braking increase instruction process is started at the same time as the second brake decrease instruction process and the first drive decrease instruction process.

The first braking increase instruction process includes a first increase instruction period process, a retention period process executed after the end of the first increase instruction period process, and a second increase instruction period process executed after the end of the retention period process. Includes. In the first increase instruction period processing, the first instruction braking force BPTr1 is increased at a speed lower than the speed corresponding to the first braking increase amount ΔBP11. When the second braking decrease instruction process and the first drive decrease instruction process are completed and the second brake increase instruction process is started, the first increase instruction period process is also terminated.

The retention period processing is executed during the execution of the second braking increase instruction processing. In the holding period processing, the first indicated braking force BPTr1 is held. That is, in the present embodiment, when the braking force of the second wheel is increased due to the execution of the second braking increase instruction process, the braking force of the first wheel is maintained. Then, when the second braking increase instruction processing is completed, the holding period processing is also completed.

The second increase instruction period process is executed during the execution of the second drive decrease instruction process. In the second increase instruction period processing, the first instruction braking force BPTr1 is increased at a speed corresponding to the first braking increase amount ΔBP11 until the first instruction braking force BPTr1 reaches the first target braking force BPS1.

Next, with reference to FIG. 16, the parts of the actions and effects of the present embodiment that are different from those of the first embodiment and the second embodiment will be mainly described.
As shown in FIGS. 16 (a), 16 (b), (c), (d), (e), and (f), the vehicle 10 is stopped by applying braking force to the front wheels 11 and the rear wheels 12. Then, the first braking reduction instruction process of the attitude control is started from the timing T31. The first braking reduction instruction process is executed until the timing T33. Therefore, when the front wheel braking force BPF is reduced within the period from the timing T31 to the timing T33, the rotation of the front wheels 11 is allowed, and the position of the front wheels 11 in the vehicle front-rear direction X returns to the reference position of the front wheels 11. In addition, the state of the front wheel suspension 13F returns to the original state.

Because the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a becomes less than the sum of the stop holding force Fh and the first correction amount Fα at the timing T32 during the execution of the first braking reduction instruction process. By executing the first drive increase instruction process of the attitude control, the increase of the first instruction drive force DPTr1 is started. In this way, the front wheel braking force is started by starting the increase of the driving force DP of the vehicle 10 before the timing when the sum of the first indicated braking force BPTr1 and the second braking force previous value BP2a becomes less than the stop holding force Fh. By reducing the BPF, it is possible to enhance the effect of suppressing the vehicle 10 from sliding down. Then, since the first braking decrease instruction process is terminated at the timing T33, the drive increase instruction process is switched from the first drive increase instruction process to the second drive increase instruction process.

The second drive increase instruction process is terminated at the timing T34 when the first instruction drive force DPTr1 reaches the sum of the stop holding force Fh and the raising target force BP2t by executing the second drive increase instruction process. In the present embodiment, the raising target force BP2t is set in consideration of the second correction amount Fβ. Therefore, even if the driving force DP is increased until the driving force DP of the vehicle 10 becomes equal to the sum of the stop holding force Fh and the raising target force BP2t, the effect of suppressing the unintended start of the vehicle 10 can be enhanced.

Further, in the present embodiment, from the timing T34, in addition to the second braking decrease instruction process and the first drive decrease instruction process, the first increase instruction period process in the first brake increase instruction process is started. As a result, the reductions in the rear wheel braking force BPR and the driving force DP of the vehicle 10 are reduced, but the front wheel braking force BPF is increased. As a result, it is possible to enhance the effect of suppressing the sliding of the vehicle 10 when the reduction of the rear wheel braking force BPR and the driving force DP of the vehicle 10 is reduced.

Then, at the timing T35 when the second instruction braking force BPTr2 becomes "0 (zero)" by executing the second brake decrease instruction process, the second brake decrease instruction process is ended and the second brake increase instruction process is started. .. At the timing T35, the rear wheel braking force BPR is almost "0 (zero)", but the front wheel 11 is provided with the braking force. Therefore, even if there is some discrepancy between the driving force DP and the stop holding force Fh, it is possible to suppress the sliding down of the vehicle 10 and the unintended start of the vehicle 10. Further, in the first braking increase instruction process, the first increase instruction period process is completed and the retention period process is started. Therefore, the front wheel braking force BPF is maintained during the period when the rear wheel braking force BPR is increased. Then, when the second instruction braking force BPTr2 reaches the second target braking force BPS2 at the timing T36, the second braking increase instruction process is terminated. Further, the first drive reduction instruction processing is completed, and the second drive reduction instruction processing is started. Further, in the first braking increase instruction process, the holding period process is completed and the second increase instruction period process is started.

(Change example)
Each of the above embodiments can be modified and implemented as follows. Each of the above embodiments and the following modified examples can be implemented in combination with each other within a technically consistent range.

-In each of the above embodiments, the decrease in the driving force DP of the vehicle 10 due to the implementation of the drive decrease control is completed before the increase in the braking force BP of the vehicle 10 due to the implementation of the braking increase control is completed. .. However, after the increase in the braking force BP of the vehicle 10 due to the execution of the braking increase control is completed, the decrease in the driving force DP of the vehicle 10 due to the execution of the drive reduction control may be completed.

-In the first embodiment and the second embodiment, the drive decrease control may be started after the braking increase control is completed.
-In the first embodiment and the second embodiment, when it can be predicted that the vehicle 10 will start relatively early after the vehicle 10 is stopped, it is not necessary to implement the braking increase control.

-In the braking increase control implemented in the first embodiment and the second embodiment, the first braking increase instruction process is started after the second brake increase instruction process is completed. However, if the braking force BP of the vehicle 10 can be increased by executing the braking increase control, the first braking increase instruction process may be started while the second brake increase instruction process is being executed.

-In the braking increase control implemented in the first embodiment and the second embodiment, the second braking increase instruction process is started before the first brake increase instruction process. However, if the braking force BP of the vehicle 10 can be increased by implementing the braking increase control, the first braking increase instruction process may be started at the same time as the second brake increase instruction process. Further, the first braking increase instruction process may be started before the second braking increase instruction process.

-In the first embodiment and the second embodiment, if the braking force BP of the vehicle 10 can be increased by implementing the braking increase control and the stopping of the vehicle 10 can be maintained by the braking force BP, braking It is not necessary to increase both the front wheel braking force BPF and the rear wheel braking force BPR by implementing the increase control. For example, the braking increase control may be a control that instructs the braking device 20 to increase only one of the front wheel braking force BPF and the rear wheel braking force BPR.

In the first embodiment, as shown in FIG. 12, the second braking decrease instruction process is performed in a state where the second drive increase instruction process is completed and the first instruction drive force DPTr1 is held by the stop holding force Fh. Is to be started. However, if the vehicle 10 can be kept stopped during the attitude control, the second braking decrease instruction process may be started before the end of the second drive increase instruction process. For example, as shown in FIGS. 17 (a), (b), (c), (d), (e), and (f), the second drive increase instruction process is performed after the end of the first brake decrease instruction process. The second braking reduction instruction process may be started from the timing T51 at which is started. In the example shown in FIG. 17, the second instruction braking force BPTr2 becomes "0 (zero)" at the timing T52 when the first instruction driving force DPTr1 reaches the stop holding force Fh by the second drive increase instruction process. Braking reduction instruction processing is executed. However, the present invention is not limited to this, and the second braking reduction instruction process may be executed so that the second instruction braking force BPTr2 becomes “0 (zero)” after the timing T52.

-In the first embodiment, when the second braking reduction instruction process is executed, a braking force may be applied to the front wheels 11 as in the case of the third embodiment.
A vehicle equipped with the attitude control device 40 may be provided with a driving device that outputs a driving force to the rear wheels 12 but does not output a driving force to the front wheels 11. When the driving device is controlled in the attitude control, the rear wheels 12 correspond to the first wheels and the front wheels 11 correspond to the second wheels.

-Attitude control may be performed when the vehicle is stopped on a downhill road. In this case, in the attitude control, the instruction driving force such that the driving force for reversing the vehicle is output from the power unit 31 to the first wheel is output to the drive control unit 32. As a result, it is possible to reduce the front wheel braking force BPF and the rear wheel braking force BPR while suppressing the vehicle 10 from moving to the downhill side due to the driving force DP of the vehicle.

The attitude control device 40 may have any of the following configurations (a) to (c).
(A) It includes one or more processors that execute various processes according to a computer program. The processor includes a CPU and memories such as RAM and ROM. The memory stores a program code or a command configured to cause the CPU to execute the process. Memory, a computer-readable medium, includes any available medium accessible by a general purpose or dedicated computer.
(B) One or more dedicated hardware circuits for executing various processes are provided. Dedicated hardware circuits include, for example, application-specific integrated circuits, i.e. ASICs or FPGAs. ASIC is an abbreviation for "Application Specific Integrated Circuit", and FPGA is an abbreviation for "Field Programmable Gate Array".
(C) A processor that executes a part of various processes according to a computer program and a dedicated hardware circuit that executes the remaining processes of the various processes are provided.

The braking control unit 22 of the braking device 20 may have any of the above configurations (a) to (c).
The drive control unit 32 of the drive device 30 may have any of the above configurations (a) to (c).

10 ... Vehicle, 11 ... Front wheel, 12 ... Rear wheel, 20 ... Braking device, 30 ... Drive device, 40 ... Attitude control device as control device, 42 ... Attitude control unit, 43 ... Braking increase instruction unit, 44 ... Drive decrease Indicator.

Claims (8)

A vehicle control device that controls a vehicle drive device and a braking device.
When the vehicle is stopped on a slope by applying braking force to the front and rear wheels of the vehicle, the braking device is instructed to reduce the braking force of the front wheels and the braking force of the rear wheels, and the vehicle is kept stopped. An attitude control unit that performs attitude control that instructs the drive device to increase the driving force of the vehicle within the range of
Braking that implements braking increase control that instructs the braking device to increase the braking force of at least one of the front wheels and the rear wheels after the increase in the driving force of the vehicle due to the execution of the attitude control is completed. A vehicle control device comprising an augmentation indicator. The driving device outputs a driving force to one of the front wheels and the rear wheels, but does not output a driving force to the other wheel.
Of the front wheels and the rear wheels, when the wheel to which the driving force is output from the driving device is the first wheel and the wheel to which the driving force is not output from the driving device is the second wheel,
The attitude control is performed by driving the braking device based on the execution of the first braking reduction instruction process for instructing the braking device to reduce the braking force of the first wheel and the execution of the first braking reduction instruction process. The vehicle control device according to claim 1, further comprising a second braking reduction instruction process for instructing the braking device to reduce the braking force of the second wheel after the braking force of the wheels is reduced. The attitude control includes a drive increase instruction process for instructing the drive device to increase the drive force of the vehicle.
In the attitude control, the attitude control unit is
After starting the reduction of the braking force of the first wheel by driving the braking device based on the execution of the first braking decrease instruction process, the drive increase instruction process is started.
The second braking reduction instruction processing is started after the completion of the first braking reduction instruction processing and after the start of the increase in the driving force of the vehicle by driving the drive device based on the execution of the drive increase instruction processing. The vehicle control device according to claim 2. In the drive increase instruction process during the execution of the first braking decrease instruction process, the attitude control unit includes a surplus driving force which is a value obtained by subtracting the braking force of the first wheel from the driving force of the vehicle and the second driving force. Instruct the driving device to increase the driving force of the vehicle so that the sum of the braking force of the wheels and the braking force of the wheels is equal to or greater than the stopping and maintaining force, which is the force required to maintain the stopping of the vehicle against the action of gravity. The vehicle control device according to claim 3. The vehicle according to claim 4, wherein the attitude control unit instructs the drive device to increase the drive force to the stop maintenance force in the drive increase instruction process after the completion of the first braking decrease instruction process. Control device. The braking increase control includes a first braking increase instruction process for instructing the braking device to increase the braking force of the first wheel, and a second braking increase instructing the braking device to increase the braking force of the second wheel. Includes instruction processing and
In the braking increase control, the braking increase indicating unit is used.
After the reduction of the braking force of the first wheel by driving the braking device based on the execution of the first braking decrease instruction process is completed, the first braking increase instruction process is started.
Of claims 3 to 5, the second braking increase instruction process is started after the reduction of the braking force of the second wheel by driving the braking device based on the execution of the second braking decrease instruction process is completed. The vehicle control device according to any one item. In the braking increase control, the braking increase indicating unit is used.
The second braking increase instruction process is started prior to the first brake increase instruction process.
The braking device after the completion of the reduction of the braking force of the first wheel by driving the braking device based on the execution of the first braking reduction instruction processing and based on the execution of the second braking increase instruction processing. The vehicle control device according to claim 6, wherein the first braking increase instruction process is started after the increase of the braking force of the second wheel is started by the driving of the second wheel. A drive reduction instruction unit for performing drive reduction control for instructing the drive device to reduce the driving force of the vehicle after the increase in the driving force of the vehicle due to the execution of the attitude control is completed.
In the drive reduction control, the drive reduction instruction unit is at a speed corresponding to the increase speed of the braking force when the braking force of the vehicle is increased by driving the braking device based on the execution of the braking increase control. The vehicle control device according to claim 6 or 7, wherein the driving device is instructed to reduce the driving force of the vehicle.