WO2020085040A1 - Vehicle drive control device, vehicle drive control method, and program - Google Patents

Abstract

There has been a problem in that, if the acceleration/deceleration of a vehicle does not change in response to a change in the road width, the drivability for a driver may decrease. To address the above problem, the vehicle drive target generation unit 13 of a vehicle drive control device 1 corrects the driving force or the braking force so that the vehicle 10 reaches a target acceleration or deceleration, on the basis of the road width or the road shoulder width of a road in the travel direction of a vehicle 10 traveling while accelerating or decelerating on the road, and outputs information of the corrected driving force or braking force. A drive command unit 16 outputs a drive command for controlling the rotational speed of a right tire 7 and a left tire 8 which cause the vehicle 10 to travel, according to the information of the corrected driving force or braking force.

Description

Vehicle drive control device, vehicle drive control method, and program

The present invention relates to a vehicle drive control device, a vehicle drive control method, and a program.

▽ Recently, development of vehicle driving support technology is in progress. Known driving support technologies include a cruise control function, a lane keeping support function, an automatic driving function, an automatic emergency braking function, and an emergency steering avoidance support function.

Patent Document 1 states that "when an obstacle exists in front of the own vehicle, the vehicle characteristics are changed according to the remaining road width at the position where the obstacle exists, that is, the remaining road width through which the own vehicle can pass". Have been described.

JP, 11-348598, A

According to the technique disclosed in Patent Document 1, when the vehicle passes through the construction area in front, the vehicle is driven at a safe speed by controlling the deceleration by assuming the passing vehicle speed starting from the accelerator operation by the driver. can do. Conventionally, it has been considered that improving safety or improving deceleration performance when driving assistance or automatic driving is performed leads to improvement of drivability recognized by a driver. In the following description, drivability is an index representing the driver's sense of safety or comfort.

However, the technique disclosed in Patent Document 1 mainly contributes to the improvement of safety during driving, and is not frequently required in a normal driving scene, so that it is necessary for the driver from the viewpoint of drivability. There are few parts corresponding to the problem. In particular, in order to reflect the driver's driving intention with respect to deceleration, it is known that a change in road width as a vehicle condition has a great influence on the driving intention. However, although Patent Document 1 has a description regarding the reduction of the road width remaining amount, it does not describe the expansion of the road width. Further, the technique disclosed in Patent Document 1 does not improve the drivability of the driver, because the main content is a construction for avoiding danger by construction and parking vehicles.

However, the driver has a request to reduce the speed if the road width of the road on which the vehicle is traveling is narrow, and does not want to decrease the speed if the road width is wide. Since the difference in the speed feeling intended by the driver correlates with the magnitude of the acceleration / deceleration requested by the driver, it is considered that the request for acceleration / deceleration according to the width of the road width is generated similarly to the speed request. To be For this reason, even in a scene in which the driver does not actually recognize the danger, the conventional technique has not been able to sufficiently support the increase or decrease in the driver's sense of security.

The present invention has been made in view of such a situation, and an object thereof is to provide a driver with comfortable drivability even when the road width of a road on which a vehicle travels changes.

The vehicle drive control device according to the present invention, based on the road width or the shoulder width of the road in the traveling direction of the vehicle that accelerates or decelerates the road, the driving force for the vehicle to reach a target acceleration or deceleration. Alternatively, in order to control the rotational speed of the target generator that corrects the braking force and outputs the corrected driving force or braking force information and the corrected driving force or braking force information that drives the vehicle. And a drive command unit that outputs the drive command.

According to the present invention, the vehicle travels so as to reach the target acceleration or deceleration by the driving force or the braking force corrected based on the road width or the shoulder width of the road in the traveling direction of the vehicle that accelerates or decelerates. Therefore, the driver can be provided with comfortable drivability.
Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

It is a schematic diagram showing an example of system composition of a vehicle concerning a 1st embodiment of the present invention. It is explanatory drawing which shows the example of a change of road conditions and deceleration when the road width which concerns on the 1st Embodiment of this invention decreases. It is explanatory drawing which shows the example of a change of road conditions and deceleration when the road width increases which concerns on the 1st Embodiment of this invention. It is explanatory drawing which shows the example of the change of the road condition and acceleration when the road width which concerns on the 1st Embodiment of this invention decreases. It is explanatory drawing which shows the example of the change of the road condition and acceleration when the road width increases which concerns on the 1st Embodiment of this invention. It is a characteristic diagram which shows the relationship of the correction amount of deceleration with respect to the road width which concerns on the 1st Embodiment of this invention. It is an image figure which shows the example of the road condition ahead of the vehicle seen from the driver | operator which concerns on the 1st Embodiment of this invention. An explanatory view showing an example of a speed limit set for each road on which a vehicle travels according to the first embodiment of the present invention, and a deceleration correction coefficient for a vehicle speed (actual vehicle speed) of a vehicle traveling on this road. Is. It is a characteristic diagram which shows the relationship of the correction amount change time constant of deceleration with respect to the road width change rate which concerns on the 1st Embodiment of this invention. It is a characteristic diagram which shows the relationship of the target driving force with respect to the accelerator opening which concerns on the 1st Embodiment of this invention. FIG. 3 is an explanatory diagram showing an example of a speed limit set for each road on which a vehicle travels according to the first embodiment of the present invention and an acceleration correction coefficient for a vehicle speed (actual vehicle speed) of a vehicle traveling on this road. is there. 5 is a flowchart showing an example of processing in which the vehicle drive target generation unit according to the first embodiment of the present invention determines whether or not control of braking / driving force is applicable. 6 is a chart showing an example of timing of limiting the rate of change with respect to the target acceleration / deceleration according to the first embodiment of the present invention. It is a functional block diagram which shows the system structural example of the vehicle which has the internal combustion engine which concerns on the 2nd Embodiment of this invention.

Previously, in low-risk driving scenes, the driver was driving based on road conditions. Normally, the acceleration / deceleration control operated by the driver is performed on the assumption that a general road is used, and thus it has not been possible to cope with changes in the visual information of the driver. The change in road width has a large effect on the change in visual information. For example, at the time of deceleration of the vehicle, when the road width in the forward direction, which is the traveling direction of the vehicle, is wide, there is no problem even if the control for slowing down is performed. The discomfort in sex becomes stronger. On the contrary, if the road width is narrowed, the frequency of the driver's stepping on the brake pedal is increased in the case of a vehicle in which the driver is required to decelerate earlier, but the vehicle is controlled so as to decelerate slowly.

On the other hand, when the vehicle is accelerating, if the width of the road ahead is widened, the feeling of acceleration will decrease even if the driver depresses the accelerator pedal. For this reason, in the case of a vehicle in which control is performed to gently accelerate, the driver performs an operation of depressing the accelerator pedal again. On the contrary, when the road width in front is narrowed, the driver wants to stop the operation of accelerating, so the operation of returning the accelerator pedal is performed. As described above, it is necessary to frequently operate the brake pedal during deceleration of the vehicle and the frequent operation of the accelerator pedal during acceleration of the vehicle according to the change in the road width.

Therefore, the present inventor improves the driver's sense of security and comfort by further setting the acceleration / deceleration using the road width of the road information of the road on which the vehicle is traveling, and further enhances the drivability. We examined possible controls. Embodiments for carrying out the present invention will be described below with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same function or configuration are designated by the same reference numerals, and duplicate description will be omitted.

[First Embodiment]
(Overview)
FIG. 1 is a schematic diagram showing a system configuration example of a vehicle 10 according to the first embodiment of the present invention.
Vehicle 10 according to the present embodiment is, for example, an electric vehicle. This vehicle 10 includes a vehicle drive control device 1, a road information output device 2, a friction braking control device 3, a power equipment control device 4, a power equipment 5, a differential gear 6, a right drive shaft 7a and a right tire 7, a left drive shaft. 8a and the left tire 8.

The vehicle drive control device 1 is an example of a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The CPU reads the program code of the software that realizes each function according to the present embodiment from the ROM and executes the program code. Variables, parameters, etc. generated during the arithmetic processing are temporarily written in the RAM. The ROM is used as an example of a computer-readable non-transitory recording medium that stores programs and data necessary for the CPU to operate.

The vehicle drive control device 1 is connected to the road information output device 2, the friction braking control device 3 and the power equipment control device 4 by an in-vehicle communication function via a communication line. The vehicle drive control device 1 inputs the road information output from the road information output device 2. The road information output device 2 is a navigation system, a vehicle-mounted camera, or the like, and outputs road information regarding the road on which the vehicle 10 travels. The road information includes information such as road width, shoulder width, and road sidewall height of the road on which the vehicle 10 travels.

The vehicle drive control device 1 is also based on the position of the select lever, the depression state of the accelerator or the brake, and the like, the system start / stop of the vehicle drive system, the target drive force calculation, the friction braking control device 3 (an example of the braking control device). And the command value output to the power equipment control device 4 (an example of the power control device) can be performed. The friction braking control device 3 performs control for applying friction braking force to a brake pad (an example of a braking device) (not shown) provided on the right tire 7 and the left tire 8 of the vehicle 10. By the control of the friction braking control device 3, for example, the brake pad comes into contact with the brake disc to generate a friction braking force, and the vehicle 10 is decelerated.

The power equipment control device 4 performs control for applying a driving force to the power equipment 5 by electrically controlling an electric motor shown as the power equipment 5 (an example of the power equipment). The output shaft of the power device 5 is connected to the differential device 6 and is power-divided into a right drive shaft 7a and a left drive shaft 8a to drive the right tire 7 and the left tire 8 (an example of a drive unit) to drive the vehicle.

The vehicle drive control device 1 includes an input processing unit 11, a system control unit 12, a vehicle drive target generation unit 13, a road width correction amount 14, a distribution unit 15, and a drive command unit 16.

The road information output from the road information output device 2, the friction braking result output from the friction braking control device 3, and the power equipment control result output from the power equipment control device 4 are input to the input processing unit 11. . Then, the input processing unit 11 outputs the road information, the friction braking result, and the power device control result to the system control unit 12 and the vehicle drive target generation unit 13.

The system control unit 12 performs various controls such as system start and system stop for each device in the vehicle 10. The control instruction given by the system control unit 12 is output to the drive instruction unit 16.

The vehicle drive target generation unit 13 (an example of a target generation unit) grasps the traveling state of the vehicle 10 and generates a vehicle drive target. The vehicle driving target is, for example, an index indicating how to change the acceleration or deceleration (also referred to as “acceleration / deceleration”), the braking force or the driving force (also referred to as “braking / driving force”) of the vehicle 10. . Therefore, the vehicle drive target generation unit 13 calculates the driving force or the braking force for controlling the rotation speed of the drive unit that causes the vehicle 10 to travel in accordance with the road on which the vehicle 10 travels.

The vehicle drive target generation unit 13 drives the vehicle 10 to reach a target acceleration or deceleration based on the road width or shoulder width of the road in the traveling direction of the vehicle 10 that accelerates or decelerates the road. The force or the braking force is corrected, and the corrected driving force or braking force information is output. The vehicle drive target generation unit 13 may target acceleration / deceleration or braking / driving force (vehicle drive force) based on the road width input from the input processing unit 11, the current traveling state of the vehicle 10, the road width correction amount 14, and the like. Target) can be corrected.

Here, the vehicle drive target generation unit 13 determines the deceleration or the braking force for reaching the deceleration of the road in which the change rate of the road width in the traveling direction of the vehicle 10 (referred to as the road width change rate) exceeds the threshold. It can be calculated or corrected based on the road width. The road width change rate focusing on the change in road width is calculated by, for example, the following equation (1).
Road width change rate [%] = width change width [m] / change distance (traveling direction distance) [m] × 100 ... (1)

For example, when the length of the road from the start of the change of the road width to the end of the change is the change distance (for example, 10 m), the road width is changed based on the change width of the road width (for example, 4 m). The rate of change is calculated to be 40%. If the road width does not change, the width change width is 0 m, and the road width change rate is 0%. On the other hand, if the road width change rate is about 40%, the road width is decreasing or increasing. Therefore, the vehicle drive target generator 13 can determine whether the road width decreases or increases by comparing the threshold value with the road width change rate. For example, even if the road width decreases due to a parked vehicle or an obstacle on the side of the road, the road width change rate is about 0%, so the vehicle drive target generation unit 13 decreases the road width. It is possible to avoid making an erroneous decision.

After that, the vehicle drive target generation unit 13 outputs the calculated acceleration / deceleration or braking / driving force information or the corrected acceleration / deceleration or braking / driving force information to the distribution unit 15. The distribution unit 15 determines the distribution of the driving force or the driving torque of the right tire 7 and the left tire 8 and / or the distribution of the braking force or the braking torque (collectively referred to as “distribution result”). The distribution result determined by the distribution unit 15 is output to the first drive command unit 16a and the second drive command unit 16b included in the drive command unit 16.

The drive command unit 16 outputs a drive command for controlling the rotation speeds of the right tire 7 and the left tire 8 based on the input driving force or braking force information distributed by the distribution unit 15. This drive command is used to drive or brake the right tire 7 and the left tire 8.

The first drive command unit 16a outputs a drive command to the friction braking control device 3 based on the control instruction input from the system control unit 12 and the distribution result input from the distribution unit 15. This drive command is the corrected braking force and is used by the brake pad to brake the right tire 7 and the left tire 8. The friction braking control device 3 is driven by this drive command, and a braking force is generated on the right tire 7 and the left tire 8. At this time, the brake pad reduces the rotational speeds of the right tire 7 and the left tire 8 to reach the target deceleration of the vehicle 10.

The second drive command unit 16b outputs a drive command to the power equipment control device 4 based on the control instruction input from the system control unit 12 and the distribution result input from the distribution unit 15. This drive command is used by the power equipment 5 to drive the right tire 7 and the left tire 8 with the corrected drive force. This drive command drives the power equipment control device 4 to generate a driving force for the right tire 7 and the left tire 8. At this time, the power device 5 increases the number of rotations of the right tire 7 and the left tire 8 to reach the target acceleration of the vehicle 10.

As described above, the vehicle drive control device 1 can comprehensively control the system of the vehicle 10. In particular, the vehicle drive target generator 13 can determine the acceleration / deceleration of the vehicle as the target drive force. Therefore, the vehicle drive control device 1 can embody the driver's intention of acceleration / deceleration according to the depression state of the accelerator pedal and the brake pedal by the driver.

As described above, the vehicle drive target generator 13 calculates the driving force or braking force of the vehicle 10. Then, the vehicle drive target generation unit 13 uses the road width correction amount 14 as a target for the driving force or the braking force of the vehicle 10 so that the vehicle 10 reaches the target acceleration or deceleration (target acceleration / deceleration). Correct the value (target braking / driving force). Then, the first drive command unit 16a outputs a drive command for braking the vehicle 10 to the friction braking control device 3 based on the corrected target braking force. The second drive command unit 16b outputs a drive command for driving the vehicle 10 to the power equipment control device 4 based on the corrected target drive force. As a result, the rotations of the right tire 7 and the left tire 8 are driven or braked, and a comfortable longitudinal acceleration can be provided to the driver.

(Items and outline required for acceleration / deceleration control using road width)
Next, an example of control of acceleration / deceleration and braking / driving force according to the present embodiment will be described with reference to the traveling scenes shown in FIGS. 2 to 5. First, an example of control during deceleration will be described with reference to FIGS. 2 and 3, and then an example of control during acceleration will be described with reference to FIGS. 4 and 5.

(Control during deceleration)
FIG. 2 is an explanatory diagram showing an example of changes in road conditions and deceleration when the road width decreases. Scenes (1) and (2) in FIG. 2 represent the vehicle 10 traveling on the road, and a chart (3) in FIG. 2 represents an example of changes in the target braking force in the scenes (1) and (2).

Scene (1) in FIG. 2 represents an example of a road whose road width gradually decreases, and scene (2) in FIG. 2 represents an example of a road whose road width suddenly decreases. As shown in scenes (1) and (2) of FIG. 2, it is assumed that the traveling vehicle 10 (own vehicle) is in a decelerating state when passing a point where the road width decreases. The deceleration state is, for example, a state in which the driver depresses the brake pedal, or a state in which the driver releases the accelerator pedal to decelerate by engine braking.

At this time, the driver of the vehicle 10 starts the deceleration state from a position before the road width starts to decrease. Here, if there is no control for correcting the target braking force, the target braking force is constant, as indicated by the alternate long and short dash line 30 in the chart (3) of FIG. Therefore, the driver tends to feel a sense of oppression when the vehicle 10 travels on a road with a narrow road width while the deceleration remains unchanged.

Therefore, as shown by the thick solid line 31 in the chart (3) of FIG. 2, control for increasing the target braking force is performed. In the following description and the drawings, the expressions “with control” and “without control” do not indicate during control and other than during control, but indicate the difference in control amount. That is, in the portion described as “with control”, the control amount (target braking force or target driving force) is described as “without control” because the control according to the present embodiment is performed. Indicates that the number has increased or decreased than the number of points.

At this time, the vehicle drive target generation unit 13 is corrected to a target braking force that increases the deceleration by the deceleration control correction amount 32 according to the road conditions. Since the deceleration of the vehicle 10 increases by the deceleration control correction amount 32, the driver can increase the sense of security by determining that the vehicle 10 is increasing the deceleration as the road width decreases. In this way, the value of the deceleration control correction amount 32 is set for the purpose of increasing the driver's sense of security. The deceleration control correction amount 32 is a value included in the road width correction amount 14 of FIG.

Also, when increasing the braking force, if the decrease in road width is a gradual change, there is no problem in changing the braking force at a constant change rate 33. However, if the decrease in road width changes abruptly, if the deceleration also changes abruptly, the driver is likely to be shocked during deceleration and to feel discomfort. Therefore, it is necessary to prevent a sudden change in deceleration.

Therefore, the vehicle drive target generation unit 13 limits the deceleration or the change in the braking force for reaching the deceleration during the period in which the friction braking control device 3 is braked based on the drive command. For example, as represented by the change rate limit during deceleration 34 in the chart (3) of FIG. 2, the vehicle drive target generation unit 13 sets a limit on the change rate of the target braking force. By providing the restriction on the rate of change, it is possible to increase the target braking force by following the decrease in the road width while reducing the driver's discomfort during deceleration of the vehicle 10.

Furthermore, by starting to increase the deceleration before the road width actually decreases, the vehicle 10 can behave according to the driver's forward vision. Therefore, the start of the road width used for the calculation is the road width in front of the vehicle 10 like the front distance 35 when the width is reduced. Therefore, the target braking force does not increase at the point where the vehicle 10 actually reduces the road width, but the target braking force increases before the road width starts to decrease, which causes the driver to increase the deceleration. You can give a sense of security.

FIG. 3 is an explanatory diagram showing an example of changes in road conditions and deceleration when the road width increases. Scenes (1) and (2) in FIG. 3 represent an example in which the vehicle 10 travels on a road without changing lanes, and a chart (3) in FIG. 3 shows a target braking force in scenes (1) and (2). Represents an example of the change of. Similarly, scene (4) in FIG. 3 shows a state in which the vehicle 10 changes lanes and approaches the front vehicle 20, and chart (5) in FIG. 3 shows an example of changes in the target braking force in scene (4). Represents

Scene (1) in FIG. 3 shows an example of a road in which the road width gradually expands, and scene (2) in FIG. 3 shows an example of a road in which the road width suddenly expands. As shown in scenes (1) and (2) of FIG. 3, it is assumed that the traveling vehicle 10 (own vehicle) is in a decelerating state when passing a point where the road width increases.

At this time, the driver of the vehicle 10 maintains the deceleration state, but if there is no control for correcting the target braking force, the target braking force is constant as indicated by the one-dot chain line 30 in the chart (3) of FIG. is there. For this reason, the vehicle 10 remains decelerated at the point where the road width has increased, and the driver feels that the vehicle 10 is decelerating too much.

Then, as shown by the thick solid line 31 in the chart (3) of FIG. 3, control for weakening the target braking force is performed. At this time, the vehicle drive target generator 13 calculates a target braking force that reduces the deceleration by the deceleration control correction amount 32 according to the road condition. The deceleration control correction amount 32 may be set separately for the increase or decrease of the road width, or may be a value according to the road width. Since the deceleration of the vehicle 10 is reduced by the deceleration control correction amount 32, the driver can increase the sense of security by determining that the vehicle 10 is weakening the deceleration as the road width increases. In this way, the value of the deceleration control correction amount 32 is set in order to suppress the decrease in the speed of the vehicle 10.

Further, similar to the reduction of the road width shown in FIG. 2, when the target braking force is reduced and the expansion of the road width is a gradual change, the braking force is changed at a constant change rate 33. Absent. However, if the expansion of the road width changes abruptly, if the deceleration also changes abruptly, there is a feeling of strangeness as if the vehicle 10 accelerated too much even though the driver maintained a decelerated state. Easy to get up. Therefore, it is necessary to prevent a sudden change in deceleration.

Therefore, as shown by the change rate limit 34 during deceleration in the chart (3) of FIG. 3, a limit on the change rate of the target braking force is set. Since the restriction of the rate of change is provided, it is possible to increase the target braking force by following the expansion of the road width while reducing the driver's discomfort during deceleration of the vehicle 10.

Further, as in the case where the road width is reduced as described with reference to FIG. 2, when the deceleration is started to be weakened before the road width is actually increased, the driver may feel It can be a feeling that 10 is about to accelerate. Therefore, the start of the road width used for the calculation when the road width increases is separated from the road width decrease front distance 35 shown in the chart (3) of FIG. 2 in the road width decrease as shown by the road width increase front distance 44. To set. For example, the width increasing front distance 44 is set to a value longer than the width decreasing front distance 35. By providing the front distance 44 at the time of increasing the width, the target braking force decreases before the road width starts to increase, so the driver is less decelerated, that is, the vehicle 10 naturally feels as if the vehicle is accelerating. Can be given.

Also, scene (4) in FIG. 3 shows a case where the vehicle 10 changes lanes because the road width has expanded and the one-lane road has become two lanes. It should be noted that scene (4) in FIG. 3 collectively expresses the moderate increase in road width shown in scene (1) in FIG. 3 and the sudden increase in road width shown in scene (2) in FIG.

Even when the vehicle 10 changes lanes, the same control as the chart (3) in FIG. 3 is performed. That is, the target braking force is reduced due to the increased road width. However, since the front vehicle 20 is traveling before the vehicle 10 changes lanes, if the target braking force of the vehicle 10 remains reduced, the vehicle 10 approaches the front vehicle 20 too much. Since the deceleration must be increased in order to avoid the danger of the vehicle 10, the control according to the present embodiment is deviated so that the deceleration of another control function is used.

For example, if the target braking force is not controlled, the constant target braking force indicated by the one-dot chain line 30 increases to the target braking force indicated by the two-dot chain line 40 in the chart (5) of FIG.
On the other hand, if the deceleration control force is reduced, the vehicle 10 approaches the preceding vehicle 20 earlier than the driver intended, so the vehicle drive target generator 13 increases the deceleration by the deceleration control correction amount 41. A target braking force that causes the calculation is calculated. The deceleration control correction amount 41 is a value included in the road width correction amount 14 of FIG. Therefore, the reduced target braking force indicated by the thick solid line 31 increases to the target braking force indicated by the thick broken line 43. By this control, it is possible to prevent the vehicle 10 from approaching the forward vehicle 20 too much.

However, a change rate limit, such as the change rate 42 at the time of control release, is set within the range of the target change time for risk avoidance so as not to make a sudden change during the time required to shift to the required deceleration. Since the change rate limit is provided, the target braking force increases according to the change rate 42 during control release, and the vehicle 10 decelerates. For this reason, it is possible to achieve appropriate deceleration so that the vehicle 10 does not approach the front vehicle 20 too much, and at the same time, it is possible to reduce shock to the driver during deceleration.

(Control during acceleration)
FIG. 4 is an explanatory diagram showing an example of changes in road condition and acceleration when the road width decreases. Scenes (1) and (2) in FIG. 4 represent the vehicle 10 traveling on the road, and a chart (3) in FIG. 4 represents an example of changes in the target driving force in the scenes (1) and (2).

Scene (1) in FIG. 4 represents an example of a road whose road width gradually decreases, and scene (2) in FIG. 4 represents an example of a road whose road width suddenly decreases. As shown in scenes (1) and (2) of FIG. 4, it is assumed that the running vehicle 10 (own vehicle) is in an accelerating state when passing a point where the road width decreases. The acceleration state is a state in which the vehicle accelerates when the driver depresses the accelerator pedal.

At this time, the driver of the vehicle 10 starts the acceleration state by depressing the accelerator pedal from a position before the road width starts to decrease. Here, if there is no control for correcting the target driving force, the target driving force is constant, as indicated by the chain line 50 in the chart (3) of FIG. Therefore, the driver is likely to feel a sense of oppression when the vehicle 10 travels on a road with a narrow road width while the acceleration remains unchanged.

Therefore, as shown by the thick solid line 51 in the chart (3) of FIG. 4, control for weakening the target driving force is performed. At this time, the vehicle drive target generator 13 corrects the target drive force so as to reduce the acceleration by the acceleration control correction amount 52 according to the road condition. The corrected target driving force reduces the acceleration of the vehicle 10 by the acceleration control correction amount 52. Therefore, the driver can determine that the acceleration of the vehicle 10 is weakened as the road width decreases and increase the sense of security. . In this way, the value of the acceleration control correction amount 52 is set aiming at the effect of increasing the driver's sense of security. The acceleration control correction amount 52 is a value included in the road width correction amount 14 of FIG.

Also, when increasing the driving force, if the decrease in road width is a gradual change, there is no problem in changing the driving force at a constant rate of change 53. However, if the decrease in road width changes abruptly, if the acceleration also changes abruptly, a shock during deceleration is applied to the driver, and discomfort is likely to occur. Therefore, it is necessary to prevent a rapid change in acceleration.

Therefore, the vehicle drive target generation unit 13 limits the acceleration or the change in the driving force for reaching the acceleration during the period in which the power equipment control device 4 is controlled based on the drive command. For example, as shown by the change rate limit during acceleration 54 in the chart (3) of FIG. 4, the change rate limit of the target driving force is limited. By limiting the rate of change, it is possible to reduce the target driving force by following the decrease in road width while reducing the driver's discomfort during deceleration of the vehicle 10.

Furthermore, by starting to decrease the acceleration before the road width actually decreases, the vehicle 10 can behave according to the driver's forward vision. Therefore, the start of the road width used for the calculation is the road width in front of the vehicle 10 like the front distance 55 when the width is reduced. For this reason, the target driving force does not decrease at the point where the vehicle 10 actually decreases the road width, but the target driving force decreases before the road width starts to decrease, so the driver is relieved that the acceleration decreases. It can give a feeling.

FIG. 5 is an explanatory diagram showing an example of changes in road conditions and acceleration when the road width increases. Scenes (1) and (2) of FIG. 5 represent an example in which the vehicle 10 travels on a road without changing lanes, and a chart (3) of FIG. 5 shows a target driving force in scenes (1) and (2). Represents an example of the change of. Similarly, scene (4) in FIG. 5 shows the vehicle 10 changing lanes and approaching the vehicle 20 in front, and chart (5) in FIG. 5 shows an example of changes in the target driving force in scene (4). Represents

Scene (1) in FIG. 5 shows an example of a road whose road width gradually expands, and scene (2) in FIG. 5 shows an example of a road whose road width suddenly expands. As shown in scenes (1) and (2) of FIG. 5, it is assumed that the moving vehicle 10 (own vehicle) is in an accelerating state when passing a point where the road width increases.

At this time, the driver of the vehicle 10 maintains the accelerating state, but if the control for correcting the target driving force is not performed, the target driving force is constant as indicated by the chain line 50 in the chart (3) of FIG. is there. For this reason, the vehicle 10 remains accelerated at the point where the road width is increased, and the driver feels that the vehicle 10 is decelerating.

Therefore, as shown by the thick solid line 51 in the chart (3) of FIG. 5, control for increasing the target driving force is performed. At this time, the vehicle drive target generator 13 calculates a target drive force that increases the acceleration by the acceleration control correction amount 52 according to the road condition. The acceleration control correction amount 52 may be set separately for the increase or decrease of the road width, or may be a value according to the road width. Since the acceleration of the vehicle 10 increases by the acceleration control correction amount 52, the driver may determine that the vehicle 10 is increasing in acceleration as the road width increases, and a sense of discomfort may occur. Therefore, the value of the acceleration control correction amount 52 is set aiming at an acceleration that does not cause a feeling of strangeness due to the smallest possible increase.

Further, similar to the reduction of the road width shown in FIG. 4, when the target driving force is increased, if the expansion of the road width is a gradual change, the driving force is changed at a constant change rate 53. Absent. However, if the expansion of the road width changes abruptly, if the acceleration changes abruptly, the driver is likely to feel uncomfortable as if the vehicle 10 accelerated too much. In order to reduce this discomfort, it is necessary to prevent a sudden change in acceleration.

Therefore, as indicated by the acceleration change rate limit 54 in the chart (3) of FIG. 5, the target drive force change rate is limited. The target driving force can be increased by following the expansion of the road width while reducing the discomfort during acceleration of the vehicle 10 so that the driver does not feel an increase in acceleration that is not intended due to the restriction on the rate of change.

Further, similarly to the case where the road width decreases as described with reference to FIG. 4, when the decrease in acceleration starts before the road width actually increases, the driver is The 10 may feel like trying to accelerate unintentionally. Therefore, the start of the road width used for the calculation when the road width is increased is separated from the front distance 55 when the road width is decreased in the road width decrease shown in the chart (3) of FIG. To set. For example, the width increasing front distance 64 is set to a value longer than the width decreasing front distance 55.
By setting the front distance 64 when increasing the width, the target driving force decreases before the road width starts to increase, so that the driver can be reassured that the acceleration decreases.

Also, scene (4) in FIG. 5 shows a case where the vehicle 10 has changed lanes because the road width has expanded and the one-lane road has become two lanes. Note that the scene (4) in FIG. 5 collectively expresses the gradual expansion of the road width shown in the scene (1) of FIG. 5 and the sudden expansion of the road width shown in the scene (2) of FIG.

Even when the vehicle 10 changes lanes, the same control as in chart (3) of FIG. 5 is performed. That is, the target driving force is increased because the road width is expanded. However, since the front vehicle 20 is traveling before the vehicle 10 changes lanes, if the target driving force of the vehicle 10 continues to increase, the vehicle 10 approaches the front vehicle 20 too much. Since the acceleration has to be reduced in order to avoid the danger of the vehicle 10, the control according to the present embodiment is deviated so that the acceleration of another control function is used.

For example, if the target driving force is not controlled, the constant target driving force indicated by the one-dot chain line 50 is reduced to the target driving force indicated by the two-dot chain line 60 in the chart (5) of FIG.
On the other hand, if the target driving force is increased, the vehicle 10 approaches the front vehicle 20 earlier than the driver intended, so the vehicle drive target generator 13 determines the acceleration of the vehicle 10 by the acceleration control correction amount 61. A target driving force that reduces the amount is calculated. The acceleration control correction amount 61 is a value included in the road width correction amount 14 of FIG. Therefore, the increased target driving force indicated by the thick solid line 51 is corrected to the decreased target driving force indicated by the thick broken line 63. Therefore, the acceleration of the vehicle 10 is reduced, and it is possible to prevent the vehicle 10 from approaching the forward vehicle 20 too much.

However, a change rate limit, such as the change rate 62 at control release, is set within the target change time range for danger avoidance so as not to make a sudden change during the time required to shift to the required acceleration. Since the change rate limit is provided, the target driving force decreases according to the change rate 62 at the time of control release, and the vehicle 10 decelerates. For this reason, it is possible to achieve appropriate acceleration so that the vehicle 10 does not approach the front vehicle 20 too much, and at the same time, it is possible to reduce shock to the driver during deceleration.

(Deceleration correction value for road width)
Here, an example of calculating the deceleration correction value will be described with reference to FIGS. 6 to 9.
The increase of the target braking force, that is, the setting of the deceleration of the vehicle 10 with the decrease of the road width shown in FIGS. 2 and 3 can be realized by using the characteristic diagram shown in FIG.
FIG. 6 is a characteristic diagram showing the relationship between the road width and the correction amount of deceleration. In this characteristic diagram, the horizontal axis is the road width and the vertical axis is the deceleration correction amount.

The vehicle drive target generation unit 13 determines the deceleration of the vehicle 10 traveling at a reduced speed or the braking force for reaching the deceleration based on the road width or the shoulder width of the road in the traveling direction of the vehicle 10. Correct to reach the target deceleration. Therefore, the vehicle drive target generation unit 13 calculates or corrects the deceleration of the vehicle 10 or the braking force for reaching the deceleration based on the road width of the road whose rate of change of the road width exceeds the threshold value. The process of calculating the braking force is performed based on the characteristic diagram showing the relationship between the road width and the correction amount shown in FIG. The vehicle drive target generation unit 13 may calculate or correct the deceleration of the vehicle 10 or the braking force for reaching the deceleration by multiplying the road width by a predetermined coefficient.

The straight line 71 shown in FIG. 6 shows that the wider the road width, the larger the correction amount and the deceleration, and the narrower the road width, the smaller the correction amount and the smaller the deceleration. Therefore, for example, if the road on which the vehicle 10 is traveling is two lanes, the deceleration correction amount is set to 0, and if the road is one lane, the deceleration correction amount is set to be large, and the road is three lanes. If so, it is possible to make a correction such as reducing the correction amount of deceleration.

(Deceleration correction value for shoulder width)
Further, the correction amount of deceleration may be changed according to the width of the road shoulder width. In FIG. 6, straight lines 70, 71 and 72 showing the respective deceleration correction amounts when the road shoulder width is narrow to wide. For example, the deceleration correction amount is obtained by multiplying the correction amount of the straight line 71 by 0.8 as a predetermined coefficient when the road shoulder width is narrow with the straight line 71 as a reference, and when the road shoulder width is wide. , 1.2 is obtained as a straight line 72 obtained by multiplying the correction amount of the straight line 71 by 1.2. Therefore, the vehicle drive target generation unit 13 can correct the deceleration or the braking force for reaching the deceleration by the shoulder width included in the road information. By adding a correction amount according to the road shoulder width to the deceleration in this way, finer control for calculating the deceleration becomes possible.

In FIG. 6, the relationship between the road width and the correction amount is shown by a straight line, but it may be shown by a curve. Further, it is effective to change the correction amount so that the driver does not assume acceleration due to the reduction in deceleration feeling that occurs when the road width increases.

(Deceleration correction value for the height of the side wall of the road)
By the way, as described with reference to FIG. 6, in order to correct the deceleration by using the road width, it is necessary to clearly image the driver's viewpoint.
FIG. 7 is an image diagram showing an example of road conditions in front of the vehicle 10 viewed from the driver. In FIG. 7, the road condition when the driver sees the road with two lanes on each side will be described.

Road width 80 shown in FIG. 7 represents the width of a two-lane road. The road shoulder width 81 represents the width of the road shoulders provided on the left and right of the road. The wall height 82 represents the height of the side wall of the road standing upright from the end of each road shoulder. Here, it is considered that not only the road shoulder width 81 but also the wall height 82 is changed by the driver's visual sense, which affects the feeling of acceleration or deceleration of the vehicle 10.

Therefore, the vehicle drive target generation unit 13 corrects the deceleration or the braking force for reaching the deceleration based on the height of the road side wall included in the road information. By correcting the deceleration in consideration of the wall height 82, the driver's intention can be set more finely. For this setting, the wall height correction value obtained by the following equation (2) can be added to the deceleration correction amount. The first correction coefficient in Expression (2) is used to increase the deceleration as the wall height 82 increases.
Wall height correction value = wall height × first correction coefficient (2)

(Deceleration correction value based on speed limit and actual speed)
As described above, the acceleration / deceleration can be performed in consideration of the driver's intention by correcting the deceleration in consideration of the road shoulder width 81, the wall height 82 and the like. Furthermore, by correcting the vehicle speed, which is an index of the drivability of the driver, it is possible to perform acceleration / deceleration for further improving the driver's sense of security.

FIG. 8 is an explanatory diagram showing an example of a speed limit set for each road on which the vehicle 10 travels and a deceleration correction coefficient for the vehicle speed (actual vehicle speed) of the vehicle 10 traveling on this road.

The vehicle drive target generator 13 can correct the deceleration, or the braking force for reaching the deceleration, based on the speed limit specified for each road and the actual vehicle speed of the vehicle 10. For example, when the speed limit and the actual vehicle speed of the vehicle 10 are equal, the speed limit−the actual vehicle speed = 0. For this reason, the correction coefficient becomes a value smaller than 1, and the correction in which the deceleration is reduced is performed. Here, when the vehicle speed is lower than the speed limit, the correction coefficient is a value smaller than 1 as shown in the range 91. Therefore, the deceleration is weakly reduced to reduce the driver's feeling of deceleration more than necessary. It is possible to On the other hand, when the vehicle speed is higher than the speed limit, it is possible to increase the driver's sense of security by performing a strong deceleration as shown in a range 92.

(Value of the amount of change used to calculate the deceleration of the road width)
The setting of the deceleration change rate based on the road width change rate shown in scenes (1) and (2) in FIGS. 2 and 3 can be realized by using the characteristic diagram shown in FIG.
FIG. 9 is a characteristic diagram showing the relationship between the deceleration correction amount change time constant and the road width change rate. In this characteristic diagram, the horizontal axis represents the road width change rate, and the vertical axis represents the deceleration correction amount change time constant. Here, the road width change rate is calculated by the above-described equation (1).

According to the straight line shown in FIG. 9, the steeper the road width change rate shown in the scene (2) of FIGS. 2 and 3, the smaller the correction amount change time constant becomes, and the scene (1) of FIGS. 2 and 3 is obtained. It is shown that the correction amount change time constant increases as the road width change rate shown in FIG.
In FIG. 9, the relationship between the road width change rate and the correction amount change time constant is represented by a straight line, but it may be represented by a curve.
Further, it is effective to increase the correction amount change time constant so that the reduction rate of deceleration change that occurs when the road width increases does not cause the driver to assume acceleration.

(Acceleration correction value of road width)
Next, an example of calculating the acceleration correction value will be described with reference to FIGS. 10 and 11.

As shown in FIGS. 4 and 5, the vehicle drive target generation unit 13 supplies the acceleration of the vehicle 10 that is accelerating and travels, or the driving force for reaching the acceleration to the road width or shoulder of the road in the traveling direction of the vehicle 10. Based on the width, the vehicle 10 is corrected to reach the target acceleration. Therefore, the vehicle drive target generation unit 13 can calculate or correct the acceleration of the vehicle 10 or the driving force for reaching the acceleration based on the road width of the road whose road width change rate exceeds the threshold. Here, the setting of the acceleration due to the width of the road width or the width of the shoulder width can be realized by changing the characteristics of the road width or the width of the shoulder width with respect to the reference characteristic diagram shown in FIG. 10.

FIG. 10 is a characteristic diagram showing the relationship between the target driving force and the accelerator opening. In this characteristic diagram, the horizontal axis represents the accelerator opening and the vertical axis represents the target driving force. With this characteristic diagram, the relationship with the driving force for the accelerator operation performed by the driver of the vehicle 10 is represented by a curve defined for each road width.

For example, the target driving force can be set as a mathematical expression as shown in the following expression (3).
Target driving force = line without control in characteristic diagram x (road width x coefficient) (3)

A curve 100 shown by a solid line in FIG. 10 represents a relationship between the accelerator opening and the target driving force when the control according to the present embodiment is not performed.
On the other hand, a curved line 101 indicated by a broken line represents the relationship between the accelerator opening and the target driving force when the control according to the present embodiment is performed when the road width is wide.
Further, a curve 102 indicated by a one-dot chain line represents a relationship of the target driving force with respect to the accelerator opening when the control according to the present embodiment is performed when the road width is narrow, and a curve 103 is a curve according to the road shoulder width. 5 shows a relationship between the accelerator opening and the target driving force when the control according to the embodiment is performed. Here, it is assumed that the road shoulder width assumed by the curve 103 is narrower than the road width assumed by the curve 102.

By directly changing the characteristics according to the road width shown by the curves 101 and 102, the relationship between the target driving force and the accelerator opening can be changed. Therefore, the vehicle drive target generation unit 13 can calculate or correct the acceleration of the vehicle 10 or the driving force for reaching the acceleration according to this characteristic diagram. At this time, the vehicle drive target generation unit 13 may set the target drive force so that the feeling of acceleration generated when the road width increases does not cause the driver to assume unintentional acceleration.

(Acceleration correction value for shoulder width)
Further, when the driver accelerates and the shoulder width is narrow, there is a great concern that a person, an object, or the like jumps out from the side. Therefore, it is difficult for the driver to depress the accelerator pedal, and there is a demand for the vehicle 10 not to accelerate as much as possible.

Therefore, the vehicle drive target generation unit 13 corrects the acceleration or the driving force for reaching the acceleration by the shoulder width included in the road information. For example, the vehicle drive target generation unit 13 performs correction so that the target drive force becomes smaller based on the characteristic line obtained from the shoulder width shown by the alternate long and short dash line 103 in FIG. 10.
Even when the shoulder width is wide, the vehicle drive target generator 13 may correct the target drive force so that the driver does not feel an unintentional acceleration feeling.

(Correction value for acceleration of road side wall height)
In addition, as shown in FIG. 10, when setting or correcting the target driving force in consideration of the road width, it is necessary to clearly image the driver's viewpoint.
Therefore, reference is made to FIG. 7 used when setting the target braking force during deceleration. Regarding the target driving force at the time of acceleration, not only the shoulder width 81 on the left and right of the road on which the vehicle 10 travels, but also the wall height 82 is changed by the driver's visual sense, and the acceleration feeling of the vehicle 10 is increased. Will be affected.

Therefore, the vehicle drive target generator 13 corrects the acceleration or the driving force for reaching the acceleration based on the height of the road sidewall included in the road information. For example, the vehicle drive target generation unit 13 can further finely set the driver's intention by correcting the acceleration in consideration of the wall height 82. For this setting, the wall height correction value obtained by the following equation (4) can be added to the acceleration correction amount. The second correction coefficient of Expression (4) is used to reduce the acceleration as the wall height 82 increases.
Wall height correction value = wall height × second correction coefficient (4)

(Acceleration correction value by speed limit and actual speed)
As described above, the acceleration and deceleration can be performed in consideration of the driver's intention by correcting the acceleration in consideration of the road shoulder width 81 and the wall height 82. Furthermore, by correcting the vehicle speed, which is an index of the drivability of the driver, it is possible to perform acceleration / deceleration for further improving the driver's sense of security.

FIG. 11 is an explanatory diagram showing an example of a speed limit set for each road on which the vehicle 10 travels and an acceleration correction coefficient for the vehicle speed (actual vehicle speed) of the vehicle 10 traveling on this road.

The vehicle drive target generator 13 can correct the acceleration or the driving force for reaching the acceleration based on the speed limit specified for each road and the actual vehicle speed of the vehicle 10. For example, when the speed limit and the actual vehicle speed of the vehicle 10 are equal, the speed limit−the actual vehicle speed = 0. Therefore, the correction coefficient becomes a value larger than 1, and the correction for increasing the acceleration is performed. Here, when the vehicle speed is lower than the speed limit, the correction coefficient is a value larger than 1 as shown in the range 111, and therefore the correction for increasing the acceleration is performed. Therefore, it is possible to reduce the driver's feeling of deceleration more than necessary.

On the other hand, when the vehicle speed is higher than the speed limit, the correction coefficient becomes a value of 1 or less as shown in the range 112. At this time, since the vehicle 10 is not accelerated too much by performing the correction for weakening the acceleration, it is possible to increase the driver's sense of security.

(Value of the amount of change used to calculate the acceleration of the road width)
It has been described that the process of setting the deceleration correction amount change time constant is performed using the characteristic diagram shown in FIG. 9 described above. Here, as in the case of deceleration, the correction amount change time constant during acceleration may also be changed according to the road width using the characteristic diagram shown in FIG. For example, during acceleration, as shown in scene (2) of FIGS. 4 and 5, as the road width change rate becomes steeper, the correction amount change time constant becomes smaller. On the other hand, as shown in scene (1) of FIGS. 4 and 5, as the road width change rate becomes slower, the correction amount change time constant becomes larger.

However, if a correction is made to accelerate rapidly with respect to a rapid increase in road width, there is a possibility that the driver may unintentionally accelerate. Therefore, the vehicle 10 may be corrected to be gradually accelerated by increasing the time constant of change in the correction amount of acceleration.
In addition, even in the case of acceleration when the road width is reduced, it may be preferable that the acceleration is gradually decreased rather than the acceleration feeling is rapidly decreased. Therefore, there is no problem even if the characteristics for acceleration correction are not divided according to the increase or decrease of the road width.

(Conditions for starting or ending control of braking / driving force according to road width)
Here, the conditions for starting or ending the control of the braking / driving force according to the present embodiment will be described.
FIG. 12 is a flowchart showing an example of a process in which the vehicle drive target generator 13 determines whether or not the control of the braking / driving force is applicable.

First, the vehicle drive target generation unit 13 calculates a set value or a correction value to be set according to the road width input from the input processing unit 11 (S1). Next, the vehicle drive target generator 13 limits the rate of change in target acceleration / deceleration or performs filter processing by the method shown in FIG. 13 described later (S2). The restriction of the rate of change of the target acceleration / deceleration is a process performed so that the target acceleration / deceleration does not suddenly change at the start or end of the control of the braking / driving force, as shown in FIG.
The filtering process is, for example, a process of applying the change rate limit during deceleration 34 so that the target braking force shown in FIG. 2 does not suddenly rise.

Then, the vehicle drive target generator 13 determines whether or not to use the calculated value based on the determination condition, and determines the target acceleration / deceleration or the target braking / driving force as an index. The vehicle drive target generation unit 13 operates the safety support function based on the determination condition, for example, when a parameter including an unclear road width is abnormal, or when another vehicle approaches the vehicle 10 from the front, rear, left, or right. When there is an abnormality in the in-vehicle device, the judgment is made based on the presence or absence.

In addition, the vehicle drive target generation unit 13 determines the start condition of the control performed on the power equipment 5 or the brake pad based on the drive command based on the detection state of the road width, the failure of the drive system, and the presence / absence of other driving support control. Judge. For example, if the drive system is out of order, control for immediately stopping the vehicle 10 is performed. Further, if other driving support control is performed, it is determined whether or not the braking / driving force control according to the present embodiment is performed according to the priority. As described above, the control of the braking / driving force according to the present embodiment can contribute to the driver's sense of security and the improvement of drivability in cooperation with various situation changes.

Next, the vehicle drive target generation unit 13 determines whether or not the application of the braking / driving force control according to the present embodiment is permitted (S3). If the application is permitted (YES in S3), the vehicle drive target generation unit 13 applies the braking / driving force control (S4). If not applicable (NO in S3), the vehicle drive target generation unit 13 does not apply the braking / driving force control (S4). After steps S4 and S5, the process returns to step S1 again, and the vehicle drive target generation unit 13 repeatedly executes this processing.

(Value of the amount of change used to start or end the road width)
Next, the timing of limiting the rate of change when changing the actual vehicle speed to the target acceleration / deceleration at the start or end of the control according to the present embodiment will be described.
FIG. 13 is a chart showing an example of the timing of limiting the rate of change with respect to the target acceleration / deceleration.

The chart (1) in FIG. 13 shows an example of the timing for determining whether to start or cancel the control of the braking / driving force according to the present embodiment. Initially, the braking / driving force is not controlled. When the control of the braking / driving force is started, the vehicle drive target generation unit 13 determines that “the control is in progress” from the time when the control is turned on (arrow 120 in the drawing). After that, when the control of the braking / driving force is released, it is determined to be “control released” from the time when the control is turned off (arrow 121 in the figure). Here, in the chart (1), the current time 122 and the switching target time 123 are defined after the control is turned off. The switching target time 123 is a time defined by the target arrival time 127 shown in the chart (2). Then, a period 124 obtained by subtracting the current time 122 from the switching target time 123 is shown in the figure.

The chart (2) in FIG. 13 shows an example of the target acceleration / deceleration that changes with the control of the braking / driving force shown in the chart (1). Initially, there is no control, and the vehicle 10 is traveling at a constant target acceleration / deceleration. When the control of the braking / driving force is started by the vehicle drive target generation unit 13, the acceleration / deceleration gradually changes from the time when the control is turned on (arrow 120 in the drawing). After that, since the braking / driving force with control is established, the target acceleration / deceleration decreases. The target acceleration / deceleration remains low during the control of the braking / driving force. When the control of the braking / driving force is released, the target acceleration / deceleration increases from the time when the control is turned off (arrow 121 in the figure). The target reaching time 127 is required before the reduced target acceleration / deceleration returns to the original value.

When acceleration / deceleration is different depending on whether the braking / driving force is controlled according to the present embodiment, it is necessary to limit the change in acceleration / deceleration so as not to cause a sudden change in acceleration / deceleration. However, when the control of the braking / driving force is started, there is no restriction that the control is completed within a fixed time, so the setting may be made so that the driver does not feel uncomfortable. Chart (2) shows the start change rate limit 125 at the start of control of the braking / driving force.

The change rate of the target acceleration / deceleration at the time of releasing the control of the braking / driving force will be described below.
For example, the rate of change of the target acceleration / deceleration at the time of releasing the control can be calculated using the following equation (5) with the braking / driving force without control, the braking / driving force with control, and the switching target time as variables.
Change rate of target acceleration / deceleration = (braking / driving force without control-braking / driving force with control) x ratio + braking / driving force without control (5)

Further, the ratio of the equation (5) is a value calculated by using, for example, the following equation (6) when the control is ON and 100% and the control is 0%. As described above, in the chart (1) of FIG. 13, the current time in the equation is represented by the arrow 122, the switching target time is represented by the arrow 123, and the switching target time-current time is represented by the arrow 124.
Ratio = (switch target time-current time) / switch target time (6)

As shown in chart (1), the braking / driving force with control and the braking force without control are set as 100% from the time when the control is turned off (arrow 121 in the figure) to the switching target time (arrow 123 in the figure). The driving force is switched according to the current time ratio from the control switching (arrow 121 indicating the change of control OFF). Therefore, the control of the braking / driving force is gradually weakened from the time when the control is turned off, and when the current time 122 reaches the switching target time 123, the control of the braking / driving force can be stopped. The change rate at release when the control of the braking / driving force is released is limited by the change rate limit at release 126. Therefore, it is possible to suppress a sudden change in the target acceleration / deceleration from the state in which the braking / driving force is controlled to the state in which the braking / driving force is not controlled.

Even if the change in acceleration / deceleration is limited by the control of the braking / driving force according to the present embodiment, if the vehicle 10 approaches the front vehicle 20 too much, the vehicle 10 is accelerated. To shift to high-priority control for stopping or decelerating. In this case, since the restriction on the change in acceleration / deceleration is released within a certain period of time, the acceleration / deceleration immediately changes.

(Specify front width)
The road width of the road on which the vehicle 10 travels should be obtained from the front of the vehicle 10, which is the traveling direction of the vehicle 10. The travel distance to be considered when determining the road width is a distance within a range that the driver can visually recognize, and is equal to or longer than the time required for the driver to normally operate the vehicle 10 to adjust the acceleration / deceleration. It is desirable that the distance is the distance that the vehicle 10 moves. Here, since the driver's recognition range is quite wide, if the acceleration / deceleration of the vehicle 10 changes in the extreme front, the driver feels uncomfortable even though the road width does not change.

On the contrary, the time required for the driver to operate is clear, for example, based on the idling distance when decelerating and stopping. Therefore, the vehicle drive target generation unit 13 obtains the road width, the road shoulder width, and the road shoulder height that are referred to in the control according to the present embodiment from the road information regarding the road ahead at least the free running distance of the vehicle 10. For example, the vehicle drive target generation unit 13 determines, according to the vehicle speed of the vehicle 10, a traveling distance [m] = (vehicle speed [km / h] × 1000/3600 × 0.75 [s]) or more roads ahead of the road. It is desirable to take the required value (eg road width) from the information. Then, the road shoulder width and the height of the side wall may be obtained by using the road width of the road ahead of the idling distance of the vehicle 10.

As mentioned above, there are road widths and changes in road widths that greatly affect the driver's speed. The shoulder width also affects the driver's feeling. Therefore, the braking / driving force is corrected when the acceleration / deceleration is set, so that the driver is provided with a comfortable acceleration / deceleration. In addition, the driver's drivability is improved by automatically adjusting the acceleration / deceleration by considering the height of the road side wall, the speed limit and the actual traveling speed, and the rate of change of the acceleration / deceleration based on the parameters. .

It should be noted that the vehicle drive target generation unit 13 determines whether the acceleration or deceleration or the braking / driving force changes at the start and end of the control according to the present embodiment due to control other than the control according to the present embodiment. Limits the rate of change of acceleration or deceleration and the rate of change of braking / driving force by other control. By limiting the rate of change, the control according to the present embodiment works effectively, and the driver does not feel uncomfortable in the drivability of vehicle 10.

[Second Embodiment]
(Value of amount of change used to calculate deceleration of road width (difference between electric vehicle and conventional vehicle))
Next, a vehicle according to the second embodiment of the present invention will be described. Here, a system configuration example of a vehicle (also referred to as a “conventional vehicle”) having an internal combustion engine as a drive source will be described.
FIG. 14 is a functional block diagram showing a system configuration example of a vehicle 200 having an internal combustion engine.

The external world recognition device 201 included in the vehicle 200 is an imaging device such as a camera and can image the surroundings of the vehicle 200. The position information acquisition device 202 included in the vehicle 200 is a GPS (Global Positioning System), a navigation system, or the like, and acquires position information indicating the current position of the vehicle 200. The outside world recognition device 201 and the position information acquisition device 202 output image data to the road information output device 203 connected by a communication line, and display position information of the vehicle 200, road information of the road on which the vehicle 200 travels, and the like. It is possible to output.

The road information output device 203, the vehicle drive control device 204, the transmission control device 205, the braking control device 206, and the prime mover control device 207 included in the vehicle 200 are connected by a communication line, and each device transmits its own information. Information can be shared through communication lines.

The internal configuration and functions of the vehicle drive control device 204 are similar to those of the vehicle drive control device 1 shown in FIG. That is, the vehicle drive control device 204 increases the target braking force to prevent sudden braking when the road width in front of the vehicle 200 is narrowed during deceleration of the vehicle 200, and when the road width is widened, The target braking force is reduced so that a feeling of acceleration can be obtained. On the other hand, when the vehicle 200 accelerates, the vehicle drive control device 204 reduces the target driving force so that sudden braking does not occur when the road width in front of the vehicle 200 narrows, and when the road width widens, The target driving force is increased so that a feeling of acceleration can be obtained. The decrease or increase of the target braking force and the target driving force in the present embodiment changes not only with the road width but also with the road shoulder width and the height of the road side wall. Further, the vehicle drive control device 204 changes the correction coefficient of the acceleration / deceleration with respect to the vehicle speed of the vehicle 200 according to the difference between the speed limit and the actual vehicle speed, and also changes the correction both sides or the time constant according to the road width change rate. The vehicle drive control device 204 can also change the target braking force according to the accelerator opening and the width of the road.

The prime mover 208 included in the vehicle 200 is a drive source for causing the vehicle 200 to travel, and may be an internal combustion engine or another power source as long as it can generate a deceleration force. A starting device 210 such as a clutch or a torque converter is generally connected to a prime mover output shaft 209 of the prime mover 208. Then, the prime mover output shaft 209 is connected to the transmission input shaft 211 of the transmission 212 via the starting device 210. The transmission output shaft 213 connected to the transmission 212 is connected to the differential device 214. The differential device 214 power-divides the right drive shaft 215a and the left drive shaft 216a and drives the right tire 215 and the left tire 216 to drive the vehicle.

The difference between vehicle 200 shown in FIG. 14 and vehicle 10 shown in FIG. 1 is that a prime mover having a drive source such as an internal combustion engine is mounted as a device for generating braking / driving force of vehicle 200.
Therefore, the vehicle 200 needs a mechanism such as the starting device 210 and the transmission 212.

Since the vehicle 10 shown in FIG. 1 is an electric vehicle, deceleration occurs when the vehicle 10 is decelerated by setting the torque of the electric motor of the power equipment 5 to the deceleration side. On the other hand, when decelerating the vehicle 200 using the internal combustion engine, fuel cut or the like is performed, and a negative torque generated by friction such as pumping loss is amplified by the transmission or a friction brake is used. However, these mechanisms provided in the vehicle 200 have poor responsiveness when changing from acceleration to deceleration, and the actual deceleration tends to vary with respect to the target deceleration. Therefore, when the internal combustion engine is used as the drive source like the vehicle 200, the vehicle drive target generation unit 13 can improve the responsiveness by largely correcting the deceleration change rate.

(Regulation of road width in front (difference between electric vehicle and conventional vehicle))
Further, in order to cope with the poor responsiveness of the vehicle 200, the following method may also be used. For example, the width reduction front distance 35 shown in the chart (3) of FIG. 2 is switched to the width reduction front distance 55 shown in the chart (3) of FIG. Similarly, the width increase front distance 44 shown in the chart (3) of FIG. 3 is switched to the width increase front distance 64 shown in the chart (3) of FIG. As described above, in the case of the vehicle 200, by increasing the forward distance affected by the change in the road width used for the acceleration / deceleration determination, the change start of each mechanism included in the vehicle 200 is accelerated, and the acceleration / deceleration response is improved. can do. Therefore, even in a vehicle 200 that uses an internal combustion engine that has a poorer acceleration / deceleration response than an electric vehicle, it is possible to realize an acceleration / deceleration feeling equivalent to that of the vehicle 10 that is an electric vehicle.

(Value of amount of change used to calculate road width acceleration (difference between electric vehicle and conventional vehicle))
As described above with respect to the system difference between FIG. 1 and FIG. 14, since the responsiveness of the internal combustion engine from deceleration to acceleration is poor, the realized acceleration tends to vary. Therefore, when the drive source is the internal combustion engine, the vehicle drive target generation unit 13 can increase the responsiveness of the internal combustion engine and control the acceleration by largely correcting the acceleration change rate.

[Modification]
The power source of the vehicle may include at least one of an electric motor and an internal combustion engine. FIG. 1 illustrates an example of system control of a vehicle 10 that is an electric vehicle, and FIG. 14 illustrates a system control of a vehicle 200 that is a conventional vehicle. However, the system control according to the present embodiment is applied to a hybrid vehicle including both an electric motor and an internal combustion engine. May be applied.

Further, the present invention is not limited to the above-described embodiments, and it goes without saying that various other application examples and modifications can be made without departing from the gist of the present invention described in the claims.
For example, the above-described embodiment is a detailed and specific description of the configuration of an apparatus and a system in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of the embodiment described here can be replaced with the configuration of another embodiment, and further, the configuration of another embodiment can be added to the configuration of one embodiment. It is possible. Further, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.
Further, the control lines and information lines are shown as being considered necessary for explanation, and not all control lines and information lines are shown in the product. In reality, it may be considered that almost all the configurations are connected to each other.

DESCRIPTION OF SYMBOLS 1 ... Vehicle drive control device, 2 ... Road information output device, 3 ... Friction braking control device, 4 ... Power equipment control device, 5 ... Power equipment, 6 ... Differential device, 7 ... Right tire, 8 ... Left tire, 10 ... vehicle, 11 ... input processing unit, 12 ... system control unit, 13 ... vehicle drive target generation unit, 14 ... road width correction amount, 15 ... distribution unit, 16 ... drive command unit, 16a ... first drive command unit, 16b ... Second drive command unit

Claims (15)

1. Based on the road width or shoulder width of the road in the traveling direction of the vehicle traveling by accelerating or decelerating the road, correcting the driving force or the braking force so that the vehicle reaches the target acceleration or deceleration, A target generation unit that outputs information on the corrected driving force or the braking force,
   A vehicle drive control device, comprising: a drive command unit that outputs a drive command for controlling the rotation speed of a drive unit that drives the vehicle based on the corrected information on the drive force or the braking force.
2. The drive command unit,
   A first drive command unit that outputs the drive command for the braking device to brake the drive unit with the corrected braking force to a braking control device that controls the braking device;
   A second drive command unit that outputs the drive command for the power unit to drive the drive unit with the corrected driving force, to a power control unit that controls the power unit,
   The braking device reduces the rotational speed of the drive unit to reach the target deceleration of the vehicle, or the power device increases the rotational speed of the drive unit to target the vehicle. The vehicle drive control device according to claim 1, which reaches acceleration.
3. The target generation unit calculates or corrects the deceleration or the braking force for reaching the deceleration based on the road width of the road whose rate of change of the road width exceeds a threshold value. 2. The vehicle drive control device according to 2.
4. The vehicle drive control device according to claim 3, wherein the target generation unit corrects the deceleration or the braking force for reaching the deceleration by the shoulder width or the height of a road side wall of the road.
5. The vehicle drive according to claim 2, wherein the target generation unit corrects the deceleration or the braking force for reaching the deceleration based on a speed limit defined for each road and an actual vehicle speed of the vehicle. Control device.
6. The said target production | generation part limits the change of the said braking force for reaching the said deceleration or the said deceleration during the period when the said braking control apparatus is controlled based on the said drive command. Vehicle drive control device.
7. The target generation unit calculates or corrects the acceleration or the driving force for reaching the acceleration based on the road width of the road whose rate of change of the road width exceeds a threshold value. The vehicle drive control device described.
8. The target generation unit represents a relationship with the driving force with respect to an accelerator operation performed by a driver of the vehicle, and according to a characteristic diagram defined for each road width, the acceleration, or the driving force for reaching the acceleration. The vehicle drive control device according to claim 7, which calculates or corrects.
9. The vehicle drive control device according to claim 7, wherein the target generation unit corrects the acceleration or the driving force for reaching the acceleration based on the shoulder width or the height of a road side wall of the road.
10. The vehicle drive control device according to claim 2, wherein the target generation unit corrects the acceleration or the driving force for reaching the acceleration based on a speed limit specified for each road and an actual vehicle speed of the vehicle. .
11. The vehicle drive according to claim 2, wherein the target generation unit limits the acceleration or a change in the driving force for reaching the acceleration during a period in which the power control device is controlled based on the drive command. Control device.
12. The vehicle drive control device according to claim 3 or 7, wherein the target generation unit calculates or corrects the braking force or the driving force based on the road width ahead of an idling distance of the vehicle or more.
13. The vehicle drive control device according to any one of claims 1 to 11, wherein the power source of the vehicle includes at least one of an electric motor and an internal combustion engine.
14. Based on the road width or shoulder width of the road in the traveling direction of the vehicle that accelerates or decelerates the road, the vehicle is corrected to reach the target acceleration or deceleration, and the corrected driving force or control is applied. Outputting the power information,
    A drive control method for a vehicle, comprising the step of outputting a drive command for controlling the rotation speed of a drive unit that drives the vehicle based on the corrected information on the drive force or the braking force.
15. Based on the road width or shoulder width of the road in the traveling direction of the vehicle that accelerates or decelerates the road, the vehicle is corrected to reach the target acceleration or deceleration, and the corrected driving force or control is applied. Procedure to output power information,
    A program for causing a computer to execute a procedure for outputting a drive command for controlling the rotation speed of a drive unit that drives the vehicle based on the corrected information on the drive force or the braking force.
    

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