JP2010000923A - Driving support apparatus, driving support method and driving support program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a user is prohibited from selecting whether or not to execute driving support control in a road section ahead of a vehicle. <P>SOLUTION: Characteristic information showing the characteristics of a road around the vehicle is acquired and candidate characteristic information showing the characteristics of the road as a candidate for the driving support control is acquired. In this case, when the characteristics corresponding to the characteristics shown by the candidate characteristic information is included in the characteristic information, a guidance is given to prompt the user to select whether or not to execute the driving support control. Then, the information showing the user's selection is acquired. When the user selects the execution of the driving support control, the driving support control is carried out. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a driving support apparatus, method, and program for supporting driving of a vehicle.

Conventionally, as a device for controlling the braking force of a vehicle, switching to a gear stage that can obtain a deceleration closest to the target deceleration within a range not exceeding the target deceleration, and using the engine brake while using the engine brake at the gear stage. A technique is known in which deceleration that is insufficient for deceleration is compensated with a brake for deceleration (see, for example, Patent Document 1).
Japanese Patent No. 3858952

In the conventional technology, the user cannot select whether or not to perform driving support control such as switching of the gear ratio and deceleration by braking in the road section ahead of the host vehicle.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique that allows a user to select whether or not to perform driving support control when traveling on a target road section. And

  In order to achieve the above object, in the present invention, the feature information indicating the characteristics of the road around the host vehicle is acquired, the candidate feature information indicating the characteristics of the road as a candidate for performing the driving support control is acquired, When a feature that matches the feature indicated in the candidate feature information is included in the feature information, guidance is provided to allow the user to select whether or not the driving support control is to be performed, and information indicating the user's selection is acquired. When the user selects to permit the execution of the driving support control, the driving support control is performed. According to this configuration, when the characteristics of the road that is a candidate for driving support control and the characteristics of the road around the host vehicle match, the user determines whether to execute the driving support control by the driving support device. You can choose. Even road sections having the same characteristics may or may not be desired to be subjected to driving support control depending on the user's feelings. According to the present invention, the driving support control can be performed only when the user desires to perform the operation.

  The feature information acquisition unit only needs to be able to acquire feature information indicating features of roads around the host vehicle. The road features may be assumed to be features expressed by road surface conditions, surrounding environment, road gradient, road shape, and the like. For example, the image information captured by the camera may be acquired to extract the characteristics of the road surface and the surrounding environment. Also, for example, information indicating the slipperiness of the road surface may be acquired from the road surface μ sensor, or road feature information around the host vehicle may be acquired by road-to-vehicle communication, vehicle-to-vehicle communication, or other communication. Alternatively, the road feature information may be extracted with reference to the map information.

  The candidate feature information acquisition unit only needs to be able to acquire candidate feature information indicating road features that are candidates for performing driving support control. The candidate feature information is used to determine whether or not the feature of the road around the host vehicle acquired by the feature information acquisition unit is a feature that is a candidate for performing driving support control. The candidate feature information may be obtained as candidate feature information stored in advance in a recording medium. The user may be able to set candidate feature information in advance.

  The guidance means determines whether or not a feature that matches the feature indicated in the candidate feature information is included in the feature information, and if so, performs guidance for allowing the user to select whether or not to perform driving support control. If you can. The guidance may be made by voice, may be guided by displaying on a display, or may be guided by a method such as emphasizing a button or a switch described later.

  A selection information acquisition means acquires the information which shows whether the selection is possible, when a user selects implementation propriety according to the above-mentioned guidance. The configuration for inputting the user's selection is not particularly limited. For example, the user selects whether or not to perform the operation by operating a switch provided on the touch panel or the steering operation unit, and the selection information acquisition unit determines whether the operation is possible or not. You may make it acquire the information which shows whether there exists. Moreover, the voice which a user utters is analyzed, and the information which shows whether the user's selection is possible may be acquired.

  The driving support control means performs the driving support control when the user selects to permit the driving support control. The driving support control includes various controls for supporting the driving operation of the user. For example, it may be a control for decelerating the host vehicle, a control for switching the speed ratio of the host vehicle, or a control for performing guidance for prompting a deceleration or a shift.

  Further, the driving support control means includes a vehicle speed information acquisition unit that acquires a target vehicle speed when traveling in a predetermined section ahead of the host vehicle, and sets the host vehicle to a vehicle speed greater than the target vehicle speed after traveling in the predetermined section. An acceleration gear ratio acquisition unit that acquires an acceleration gear ratio that is a gear ratio for acceleration, and a gear ratio control unit that sets the gear ratio of the host vehicle to the acceleration gear ratio before reaching the start point of the predetermined section And a deceleration control unit that decelerates the vehicle speed of the host vehicle to the target vehicle speed before reaching the start point of the predetermined section. That is, the driving support control means acquires an acceleration gear ratio for accelerating the host vehicle to a vehicle speed higher than the target vehicle speed based on the target vehicle speed when traveling in a predetermined section existing ahead of the host vehicle. Then, the speed ratio in the host vehicle is set to the acceleration gear ratio before the host vehicle reaches the start point of the predetermined section, and the vehicle speed of the host vehicle is decelerated before the host vehicle reaches the start point of the predetermined section. Car speed. That is, in the present invention, the acceleration gear ratio is determined by paying attention to the gear ratio for accelerating the host vehicle after traveling in a predetermined section. Therefore, according to the present invention, before reaching the predetermined section, the acceleration gear ratio is suitable for accelerating the host vehicle to a vehicle speed higher than the target vehicle speed, and at an acceleration stage after traveling the predetermined section. It is possible to accelerate smoothly.

  Here, the vehicle speed information acquisition unit need only be able to acquire the target vehicle speed when traveling in the predetermined section in front of the host vehicle, and may directly acquire information indicating the vehicle speed. It may be acquired indirectly. As the former, it is possible to adopt a configuration in which a target vehicle speed is associated with a predetermined section set in advance and the target vehicle speed associated with the predetermined section is acquired. As the latter, it is possible to adopt a configuration in which the target vehicle speed is determined based on information indicating a predetermined section and roads around it.

  The predetermined section may be a section where it is preferable to decelerate the host vehicle to reach the target vehicle speed before reaching the section and accelerate the host vehicle after traveling the predetermined section at the target vehicle speed. Or a section having a predetermined shape gradient. Furthermore, the target vehicle speed is a preferable vehicle speed when traveling in the predetermined section, and may be set in advance. For example, in a curve section, it is preferable to travel in a section having a constant radius in the curve section at a constant speed, so that a configuration in which the constant speed is the target vehicle speed can be employed. In addition, when a section including a slope is defined as a predetermined section on a road having a slope, the target vehicle speed is defined as decelerating to a preferable target vehicle speed in order to travel the section of the downward slope before the start point of the downward slope. A configuration can be adopted.

  The acceleration gear ratio acquisition unit only needs to be able to acquire a gear ratio for accelerating the host vehicle to a vehicle speed higher than the target vehicle speed after traveling in a predetermined section, and can at least further accelerate the target vehicle speed. It is only necessary that a correct gear ratio can be acquired. For example, it is possible to drive at a vehicle speed that is higher than the target vehicle speed when the speed ratio that can be accelerated from the target vehicle speed to a specific vehicle speed that is higher than the target vehicle speed, or when the rotational speed of the drive source is a specific value. It is sufficient if the gear ratio can be acquired. In other words, by setting these gear ratios as acceleration gear ratios and setting the acceleration gear ratio before completion of traveling in a predetermined section, acceleration can be performed without changing the gear ratio in the acceleration stage after traveling in the predetermined section. That's fine. As a result, the host vehicle can be smoothly accelerated after traveling in the predetermined section. Note that the gear ratio may be at least a gear ratio necessary and sufficient for accelerating to a vehicle speed higher than the target vehicle speed, but a gear ratio for smoothing acceleration may be determined in advance. For example, it is possible to estimate parameters such as the throttle opening / closing operation at the start of acceleration and the rotational speed of the vehicle drive source, and to select a gear ratio that can be most efficiently accelerated based on the estimation.

  The speed ratio control unit only needs to be able to set the speed ratio of the host vehicle to the acceleration speed ratio before reaching the start point of the predetermined section. In other words, if the speed ratio of the host vehicle is set to an acceleration speed ratio suitable for acceleration before reaching the start point of the predetermined section, the host vehicle traveling on the road to the predetermined section usually has a larger speed ratio. Changed to For this reason, it is possible to assist the deceleration before reaching the predetermined section by setting the speed ratio to the acceleration speed ratio. Moreover, if the acceleration gear ratio is maintained without changing after reaching the predetermined section, traveling in the predetermined section can be stabilized. Note that it is only necessary that the gear ratio can be set for a transmission unit (for example, a stepped transmission with a torque converter) mounted on the host vehicle. That is, it suffices if the transmission ratio is set by an instruction of the transmission ratio for the transmission unit, and the transmission unit can switch to the transmission ratio as instructed based on the instruction.

  The deceleration control unit only needs to be able to decelerate the vehicle speed of the host vehicle to reach the target vehicle speed before reaching the start point of the predetermined section. Therefore, it is only necessary to control a deceleration unit for decelerating the host vehicle, for example, a control device for adjusting the rotational speed of the drive source (throttle or the like) or a brake to decelerate the host vehicle. In addition, as a configuration for setting the host vehicle to the target vehicle speed, for example, a configuration in which deceleration is performed by feedback control with respect to a reference parameter can be employed. The reference parameter may be an index used as a reference when the vehicle speed of the host vehicle is set as the target vehicle speed, and the target vehicle speed within the distance from the current position of the host vehicle to the start point of the predetermined section is targeted. The deceleration required for achieving the vehicle speed, the transition of the vehicle speed, and the like can be used as these reference parameters.

  Further, when the feature information includes a feature that matches the feature indicated by the candidate feature information as in the present invention, the user is allowed to select whether or not the driving support control can be performed, and the user permits the driving support control to be performed. When selected, the method of performing driving support control is also applicable as a program or method. In addition, the above-described driving support device, program, and method may be realized as a single driving support device, or may be realized by using parts shared with each part provided in the vehicle. The embodiment is included. For example, it is possible to provide a navigation device, a method, and a program that include the driving support device as described above. Further, some changes may be made as appropriate, such as a part of software and a part of hardware. Furthermore, the invention is also established as a recording medium for a program for controlling the driving support device. Of course, the software recording medium may be a magnetic recording medium, a magneto-optical recording medium, or any recording medium to be developed in the future.

Here, embodiments of the present invention will be described in the following order.
(1) Configuration of navigation device:
(2) Driving support processing:
(2-1) Guidance execution determination process:
(2-2) Vehicle deceleration processing:
(2-3) Deceleration start determination process:
(2-4) Deceleration control process:
(2-5) Vehicle speed limit processing:
(2-6) Gear ratio selection process:
(2-7) Gear ratio acquisition process:
(3) Other embodiments:

(1) Configuration of navigation device:
FIG. 1 is a block diagram showing a configuration of a navigation device 10 including a driving support device according to the present invention. The navigation device 10 includes a control unit 20 including a CPU, a RAM, a ROM, and the like and a recording medium 30, and the control unit 20 can execute a program stored in the recording medium 30 or the ROM. In the present embodiment, the navigation program 21 can be implemented as one of the programs, and the navigation program 21 allows the user to select whether or not the driving support control can be performed as one of the functions, and the user implements it. When this is selected, a speed ratio suitable for acceleration in the acceleration section is set and deceleration is executed in the deceleration section.

  The vehicle according to the present embodiment (the vehicle on which the navigation device 10 is mounted) has a GPS receiving unit 41, a vehicle speed sensor 42, a gyro sensor 43, a transmission unit 44, a braking unit 45, and throttle control in order to realize the function of the navigation program 21. The function by the navigation program 21 is implement | achieved when these parts and the control part 20 cooperate.

  The GPS receiver 41 receives radio waves from GPS satellites and outputs information for calculating the current position of the vehicle via an interface (not shown). The control unit 20 acquires this signal and acquires the current position of the vehicle. The vehicle speed sensor 42 outputs a signal corresponding to the rotational speed of the wheels provided in the vehicle. The control unit 20 acquires this signal via an interface (not shown) and acquires the speed of the vehicle. The gyro sensor 43 outputs a signal corresponding to the direction of the host vehicle. The control unit 20 acquires this signal via an interface (not shown) and acquires the traveling direction of the host vehicle. The vehicle speed sensor 42 and the gyro sensor 43 are used for correcting the current position of the host vehicle specified from the output signal of the GPS receiver 41. Further, the current position of the host vehicle is corrected as appropriate based on the travel locus of the host vehicle. Various other configurations can be adopted for acquiring information indicating the operation of the vehicle, such as a configuration in which the current position of the host vehicle is specified by a sensor or camera, a signal from GPS, or on a map. It is possible to adopt a configuration in which the own vehicle operation information is acquired by vehicle trajectory, vehicle-to-vehicle communication, road-to-vehicle communication, etc.

  The camera 47 is attached to the host vehicle so as to include the periphery of the host vehicle in the field of view and outputs image information indicating the captured image in order to acquire an image including the road on which the host vehicle travels and the periphery of the road. To do. The control unit 20 acquires this image information via an interface (not shown), and features of the road are extracted by a feature information acquisition unit 21a described later. In the present embodiment, as a configuration for acquiring road characteristics, a sensor (for example, a road surface μ sensor) that detects a road surface condition (not shown), a sensor (for example, a raindrop sensor) that detects a weather condition, road-to-vehicle communication, A communication unit for performing wireless communication such as vehicle-to-vehicle communication and a thermometer for measuring outside air temperature are provided. The user I / F unit 48 includes a touch panel display, a switch provided in the steering operation unit, a speaker, a microphone, and the like. The control unit 20 can guide various information to the user via the user I / F unit 48. Further, the control unit 20 can acquire information indicating a user operation via the user I / F unit 48.

  The transmission unit 44 includes a stepped torque converter having a plurality of speed stages such as a total of 6 speeds for forward and a total of 1 speed for reverse, and adjusts the rotational speed with a gear ratio corresponding to each speed. Can be transmitted to the wheels of the vehicle. The control unit 20 outputs a control signal for switching the gear position via an interface (not shown), and the transmission unit 44 can acquire the control signal and switch the gear position. In the present embodiment, the gear ratio is configured to become smaller as the gear position becomes high gear, such as the first forward speed to the sixth forward speed.

  The braking unit 45 includes a device that controls the pressure of the wheel cylinder that adjusts the degree of deceleration by the brake mounted on the wheel of the host vehicle, and the control unit 20 outputs a control signal to the braking unit 45 to output the wheel. It is possible to adjust the pressure of the cylinder. Accordingly, when the control unit 20 outputs a control signal to the braking unit 45 to increase the pressure of the wheel cylinder, the braking force by the brake increases and the host vehicle is decelerated.

  The throttle control unit 46 includes a device that controls a throttle valve for adjusting the amount of air supplied to the engine mounted on the host vehicle. The control unit 20 outputs a control signal to the throttle control unit 46. It is possible to adjust the opening of the throttle valve. Therefore, when the control unit 20 outputs a control signal to the throttle control unit 46 to increase the intake air amount, the engine speed increases. Since the control unit 20 is configured to give control instructions to the transmission unit 44 and the throttle control unit 46, the current transmission ratio Sn set by the transmission unit 44 and the throttle control unit 46 are set in the control unit 20. The current throttle opening degree Th can be acquired.

  The control unit 20 executes a navigation program 21 to perform a vehicle route search or the like based on output information of the GPS reception unit 41, map information described later, and the like, and route guidance and the like via a display unit and a speaker (not shown). I do. At this time, guidance according to the characteristics of the road around the host vehicle, acquisition of user selection information, setting of the gear ratio in the transmission unit 44 and acceleration / deceleration control using the braking unit 45 and the throttle control unit 46 are performed. Therefore, the navigation program 21 includes a feature information acquisition unit 21a, a candidate feature information acquisition unit 21b, a guide unit 21c, a selection information acquisition unit 21d, and a driving support control unit 21e.

  The recording medium 30 stores map information 30a for performing guidance by the navigation program 21. The map information 30a includes node data indicating nodes set on the road on which the vehicle travels, shape interpolation point data for specifying the shape of the road between the nodes, link data indicating the connection between the nodes, the road and its surroundings Is used for specifying the current position of the host vehicle, guiding the destination, and the like. The node data and link data are associated with information indicating the road gradient. The node data includes information indicating road attributes such as mountain roads and unpaved roads.

In the present embodiment, it is configured to perform deceleration control before reaching a curve section (a section having a constant radius), and the map information 30a includes information indicating the curve section and roads before and after the curve section. FIG. 2 is a diagram showing an example of the curve section Zr, and shows a state where the host vehicle C is traveling toward the curve section Zr indicated by a thin one-dot chain line. In the present embodiment, node data corresponding to the start point Rs of the curve section Zr is associated with information indicating the start point Rs of the curve section Zr, and node data corresponding to the end point Re of the curve section Zr. Is associated with information indicating the end point Re of the curve section Zr. Further, the shape interpolation data indicating the road shape between the start point Rs and the end point Re is data indicating the position on the arc of the curve section Zr, and a constant radius in the curve section Zr based on the shape interpolation data. The vehicle speed (target vehicle speed V ₀ ) when traveling at a constant vehicle speed in the section of R and the radius R can be specified. In the present embodiment, information indicating the start point Rs and end point Re of the curve section Zr and the shape interpolation point therebetween is referred to as curve section information 30a1.

Further, in the section until reaching the curve section Zr described above, there is a deceleration section Zd (a section indicated by a thin broken line in FIG. 2, for example, a clothoid section) for performing deceleration before reaching the curve section Zr. In the present embodiment, the node data corresponding to the start point Ca of the deceleration zone Zd is associated with information indicating the start point Ca of the deceleration zone Zd. In the present embodiment, the end point of the deceleration zone Zd coincides with the start point Rs of the curve zone Zr, and the shape between the start point Ca and the end point Rs of the deceleration zone Zd is indicated by shape interpolation data. Further, the distance L ₀ of the deceleration zone Zd can be specified based on the information indicating the positions of the start point Ca and the end point Rs of the deceleration zone Zd. In the present embodiment, information indicating the start point Ca and the end point Rs of the deceleration zone Zd and the shape interpolation data indicating the road shape between them is referred to as deceleration zone information 30a2.

  Further, in the section after the curve section Zr described above, an acceleration section Za (in FIG. 2) for accelerating toward a predetermined point (end point Ce of the acceleration section Za) after traveling the curve section Zr. A section indicated by a dotted line, for example, a clothoid section) is set, and in this embodiment, the node data corresponding to the end point Ce of the acceleration section Za indicates information indicating that the end point Ce of the acceleration section Za. Are associated. In the present embodiment, the start point of the acceleration zone Za coincides with the end point Re of the curve zone Zr, and the shape between the start point Re and the end point Ce of the acceleration zone Za is indicated by shape interpolation data.

Further, the distance L ₁ of the acceleration zone Za can be specified based on the information indicating the positions of the start point Re and the end point Ce of the acceleration zone Za. Further, the node data corresponding to the end point Ce of the acceleration zone Za is associated with the limited vehicle speed at that point, and the limited vehicle speed is the recommended vehicle speed V ₁ after traveling in the acceleration zone in the present embodiment. Furthermore, a throttle opening Th ₁ is determined in advance at the start point Re of the acceleration zone Za for performing acceleration control described later, the throttle opening Th ₁ node data corresponding to the end point Ce of the acceleration zone Za The information shown is associated. In the present embodiment, the start point Re of the acceleration zone Za and the end point Ce, the shape interpolation data indicating the road shape therebetween the recommended vehicle speed V ₁ and the acceleration information indicating the throttle opening Th ₁ section information 30a3 Call.

  The feature information acquisition unit 21a is a module for acquiring feature information indicating features of roads around the host vehicle. The road features may be assumed to be features expressed by road surface conditions, surrounding environment, road gradient, road shape, and the like. For example, image information captured by the camera 47 may be acquired to extract features of the road surface and surrounding environment. Further, for example, information indicating the slipperiness of the road surface may be acquired from a road surface μ sensor, a raindrop sensor, a thermometer, or the like (not shown). Further, road feature information around the host vehicle may be acquired by road-to-vehicle communication, vehicle-to-vehicle communication, or other communication, or the road feature information may be acquired by referring to the map information 30a.

  The candidate feature information acquisition unit 21b is a module for acquiring candidate feature information indicating road features that are candidates for performing driving support control. In this embodiment, the control unit 20 includes a candidate feature information acquisition unit. The candidate feature information 30b stored in advance in the recording medium 30 is acquired by the processing of 21b. Note that the user may be able to select in advance candidate feature information used for determination in the guidance execution determination process described later. In the guidance execution determination process, the determination process is performed only on preset candidate feature information. May be.

  The candidate feature information 30b is used to determine whether or not the feature of the road around the host vehicle acquired by the processing of the feature information acquisition unit 21a is a feature that is a candidate for performing driving support control. The In the present embodiment, the candidate feature information 30b includes information indicating a road surface condition, information indicating an environment around a road, and information indicating a road gradient. More specifically, it includes a threshold value of the friction coefficient of the road surface, information indicating the characteristics of the image of the unpaved road, information indicating that the road attribute is a mountain road or an unpaved road, a threshold value of the road gradient, and the like. Yes.

  The guidance unit 21c is a module for performing guidance for allowing the user to select whether or not to perform driving support control when a feature that matches the feature indicated by the candidate feature information is included in the feature information. In the present embodiment, guidance is performed by displaying a screen for selecting whether or not driving support control can be performed on a touch panel display (not shown).

  The selection information acquisition unit 21d is a module for acquiring information indicating whether the selection is possible or not when the user selects the availability according to the guidance by the guidance unit 21c. As a configuration for inputting a user's selection, in this embodiment, by touching a button for selecting whether or not to perform displayed on the touch panel display, or by operating a switch provided in the steering operation unit. The selection information acquisition unit 21d adopts a configuration that acquires information indicating whether the operation is possible or not.

The driving support control unit 21e includes a vehicle speed information acquisition unit 21e1, an acceleration gear ratio acquisition unit 21e2 (including a necessary acceleration amount acquisition unit not shown), a gear ratio control unit 21e3, a deceleration control unit 21e4, and an acceleration control unit 21e5. . Vehicle speed information obtaining unit 21e1 is a module that acquires the recommended vehicle speed V ₁ of the post-travel target vehicle speed V ₀ and the curve zone Zr when traveling the curve zone Zr, these vehicle speed information by referring to the map information 30a Is identified. That is, the control unit 20 specifies the radius R of the curve section Zr with reference to the curve section information 30a1 by the process of the vehicle speed information acquisition section 21e1, and acquires the vehicle speed for traveling in the section of the radius R at a constant vehicle speed. To the target vehicle speed V ₀ . For example, the vehicle speed (Gt · R) ^1/2 for traveling at a constant vehicle speed at a preset lateral acceleration Gt (for example, 0.2 G) is acquired as the target vehicle speed V ₀ . Further, the recommended vehicle speed V ₁ is acquired with reference to the acceleration section information 30a3.

The necessary acceleration amount acquisition unit is a module for acquiring a necessary acceleration amount for accelerating the host vehicle from the target vehicle speed V ₀ to the recommended vehicle speed V ₁ , and the control unit 20 performs an acceleration section by processing of the necessary acceleration amount acquisition unit. identify the distance L ₁ of the acceleration zone based on the information 30a3, and acquires the necessary acceleration a for causing accelerated from the target vehicle speed V ₀ at the distance L ₁ to the recommended vehicle speed V _1. That is, the length between the start point Re and the end point Ce along the road shape is obtained as the distance L ₁ from the information indicating the positions of the start point Re and the end point Ce of the acceleration section Za and the shape interpolation point therebetween. To do. Then, a necessary acceleration a for the target vehicle speed V ₀ at the distance L ₁ and the recommended vehicle speed V _1, for example, assuming uniform acceleration ^{_{motion, a = (V 1 2 -V}} 0 2) / (2L 1 ) And so on.

The acceleration gear ratio acquisition unit 21e2 obtains an acceleration gear ratio Sa (Sa is one of 1 to 6 (corresponding to the first to sixth forward speeds) described above) that is a gear ratio for causing the host vehicle to travel at the necessary acceleration a. The control unit 20 acquires the throttle opening Th ₁ by referring to the acceleration section information 30a3 by the processing of the acceleration gear ratio acquisition unit 21e2, and acquires the throttle opening Th ₁ , the necessary acceleration a, and the target vehicle speed V. _The gear ratio is determined based on ₀ . In the present embodiment, the vehicle speed in the host vehicle is the target vehicle speed V ₀ , and the gear ratio is such that the required acceleration a can be generated in the state where the vehicle is traveling at the engine speed corresponding to the throttle opening Th ₁ . Of these, the speed ratio at which the fuel consumption is minimized is the acceleration speed ratio Sa.

According to this configuration, the host vehicle can be accelerated from the target vehicle speed V ₀ to the recommended vehicle speed V ₁ using fuel efficiently. Here, the selection of the gear ratio employs, for example, a configuration in which a fuel consumption map associated with the engine speed and the throttle opening Th ₁ is prepared in advance and is executed based on the fuel consumption map. Is possible. Although the engine speed corresponding to the throttle opening degree Th ₁ is assumed here, it is needless to say that the speed may be determined based on a statistical value or the like.

  The transmission ratio control unit 21e3 is a module that sets the transmission ratio of the host vehicle to the acceleration transmission ratio Sa before the host vehicle reaches the start point Rs of the curve section Zr. The control unit 20 performs processing of the transmission ratio control unit 21e3. Thus, a control signal for setting the transmission gear ratio to the acceleration transmission gear ratio Sa is output to the transmission unit 44 at a predetermined timing according to the processing procedure described later. The transmission unit 44 switches the transmission gear ratio to the acceleration transmission gear ratio Sa according to the control signal.

The deceleration control unit 21e4 is a module that decelerates the vehicle speed of the host vehicle to the target vehicle speed V ₀ before the host vehicle reaches the curve section Zr. The control unit 20 performs a curve section by the process of the deceleration control unit 21e4. Feedback control is performed so that the vehicle speed becomes the target vehicle speed V ₀ at the start point Rs of Zr. That is, the current position of the host vehicle along the road shape is obtained from the information indicating the current position of the host vehicle, the end point Rs, and the position of the shape interpolation point therebetween by acquiring the target vehicle speed V ₀ and referring to the deceleration section information 30a2. And the end point Rs is acquired as the distance Lc.

Then, at the distance Lc, the necessary deceleration Gr (negative acceleration when the traveling direction of the host vehicle is positive) for setting the current vehicle speed Vc of the host vehicle to the target vehicle speed V ₀ is, for example, equal acceleration motion. Assume that Gr = (V ₀ ² −Vc ² ) / (2Lc). Furthermore, in the present embodiment, the necessary deceleration Gr is acquired sequentially, and deceleration control is started when the necessary deceleration Gr exceeds a predetermined threshold (LimG_h or LimG_L described later). That is, the deceleration Ge by the engine brake is acquired based on the current gear ratio Sn set by the transmission unit 44 and the engine speed at the current throttle opening Th adjusted by the throttle control unit 46. Then, the control unit 20 outputs a control signal for generating a deceleration corresponding to a difference (Gr−Ge) between the required deceleration Gr and the deceleration Ge to the braking unit 45. As a result, in the braking unit 45, the brake is applied so as to compensate for the difference (Gr-Ge) between the required deceleration Gr and the deceleration Ge.

  In the present embodiment, the gear ratio is switched to the acceleration gear ratio Sa during the deceleration operation in the deceleration zone Zd. At this time, usually, the gear ratio becomes higher by switching the gear ratio. For this reason, it is possible to assist the deceleration before reaching the curve section by setting the speed ratio to the acceleration speed ratio Sa.

Furthermore, the acceleration control unit 21e5 is a module for controlling acceleration after the host vehicle travels in the curve section Zr. The control unit 20 is a distance from the end point Re of the curve section Zr by the processing of the acceleration control unit 21e5. in the acceleration zone Za between L _1, and controls the throttle opening Th such that the recommended vehicle speeds V ₁ to the vehicle speed from the target vehicle speed V _0. That is, in a state where the transmission gear ratio is maintained at the acceleration transmission gear ratio Sa, a control signal is output to the throttle control unit 46 to set the throttle opening to Th ₁ , and then the acceleration is appropriately performed so that the acceleration is performed at the necessary acceleration a. Adjust the throttle opening.

According to the above configuration, the acceleration gear ratio Sa is set at the stage where the host vehicle is traveling in the deceleration zone Zd. Therefore, the acceleration suitable for accelerating to the recommended vehicle speed V ₁ when traveling in the acceleration zone Za. The speed change ratio Sa is established, and it is possible to accelerate smoothly in the acceleration zone Za. In addition, if you select a gear ratio that provides the closest deceleration to the required deceleration Gr and perform deceleration, you can effectively use the deceleration by the engine brake to reduce the speed. Due to the functioning of the vehicle, the shock applied to the vehicle at the time of shifting is relatively large. However, in the present invention, the acceleration gear ratio Sa is determined by focusing not on the deceleration at the time of deceleration but on the required acceleration a at the time of acceleration, so that the shock applied to the vehicle at the time of shifting can be suppressed to a relatively small level.

(2) Driving support processing:
Next, the driving assistance process which the navigation apparatus 10 implements in the above structure is demonstrated. When the navigation program 21 is executed by the navigation device 10, each unit included in the navigation program 21 executes the process shown in FIG. In the present embodiment, three different control states (referred to as a deceleration control state DS) are provided for the deceleration control, and three different control states (referred to as a gear ratio control state GS) are provided for the speed ratio control. Therefore, the control unit 20 initializes variables for specifying the deceleration control state DS and the gear ratio control state GS to “0” (steps S100 and S110). In the present embodiment, the state is DS = 0 is not performed to control the vehicle speed, state DS = 1 for decelerating the vehicle speed to the target vehicle speed V _0, the state to maintain the vehicle speed at the curve section is DS = 2. Further, the state where the gear ratio control is not performed is GS = 0, the state where the gear ratio calculation process is performed is GS = 1, and the state where the gear ratio switching process is performed is GS = 2.

  When the deceleration control state DS and the gear ratio control state GS are initialized, the control unit 20 acquires information on a curve section existing ahead of the host vehicle (step S120). That is, the control unit 20 specifies the current position of the host vehicle based on the output signal from the GPS receiving unit 41 and the like, and refers to the map information 30a to determine whether or not there is a curve section in a predetermined range in front of the current position. Determine whether. And when a curve section exists, the curve section information 30a1, the deceleration section information 30a2, and the acceleration section information 30a3 regarding the curve section are acquired.

  Subsequently, the control unit 20 acquires feature information indicating the characteristics of the road around the host vehicle by the process of the feature information acquisition unit 21a (step S130), and acquires the candidate feature information by the process of the candidate feature information acquisition unit 21b. (Step S135). Specifically, in step S130, the control unit 20 acquires image information in front of the host vehicle from the camera 47, and performs image recognition processing on the image information, whereby a dirt road (unpaved road), a snow road, It is determined whether or not a feature such as a blind curve (a curve with a poor forward line of sight due to a shield) is included in the image information. Subsequently, the control unit 20 determines whether or not a feature such as a mountain road or a steep downhill road is included from the road attribute associated with the link data or the node data and the road slope value. Further, it is determined whether or not the road surface is wet or frozen based on information acquired from a road surface μ sensor and a raindrop sensor (not shown) and air temperature acquired from a thermometer. Moreover, you may determine whether the above-mentioned various characteristics are included regarding the road around the own vehicle from the information acquired from the communication part which is not shown in figure.

  Subsequently, the control unit 20 executes guidance execution determination processing by the processing of the guide unit 21c (step S140), and performs processing for displaying a selection screen on the touch panel display when it is determined in step S140 that guidance is to be performed. This is executed (step S150), and the control unit 20 acquires the user's selection by the processing of the selection information acquisition unit 21d (step S160). In the present embodiment, step S140 and step S150 are executed before the host vehicle passes the start point Ca. After the information indicating the selection of whether or not to implement can be obtained in step S160, or after the host vehicle reaches the start point Rs, it is not executed until the host vehicle approaches the next curve section.

  Further, the control unit 20 executes a vehicle deceleration process (step S170) and a gear ratio selection process (step S180), acquires an output signal of an ignition switch (not shown), and determines whether or not the ignition is turned off ( Step S190). Then, the processes after step S120 are repeated until it is determined that the ignition is turned off.

(2-1) Guidance execution determination process:
FIG. 4 is a flowchart showing guidance execution determination processing. In the guidance execution determination process, the control unit 20 sequentially determines whether or not a feature that matches the feature indicated in the candidate feature information is included in the feature information. A guidance screen is generated for allowing the user to select whether or not the driving support control can be performed. In step S150 described above, the screen generated in the guidance execution determination process is displayed on the touch panel display. Specifically, for the guidance execution determination process, first, the control unit 20 determines whether or not the road surface is wet (step S800), and when it is determined that the road surface is wet, the driving support control on the wet road surface is determined. A selection screen for determining whether or not to execute is generated (step S805). In step S800, for example, when it is extracted that the vicinity of the host vehicle is raining based on information acquired from the raindrop sensor as feature information, it is determined that the vehicle is in a wet state. In step S805, for example, a selection screen as shown in FIG. 5 is generated.

  If it is not determined in step S800 that the road surface is in a wet state, the control unit 20 determines whether the road surface is in a dirt (unpaved) state (step S810), and when it is determined that the road surface is in a dirt state, A selection screen for determining whether or not the driving support control is performed on the dirt road surface is generated (step S815). For example, when image information in front of the host vehicle is acquired and the feature (road marking, road color) of the image of the paved road is not extracted from the image information, the road attribute is an unpaved road with reference to the map information 30a. In this case, the road surface of the road ahead of the host vehicle may be determined to be in a dirt state. If it is not determined in step S810 that the road surface is in a dirt state, the control unit 20 determines whether or not the road surface is frozen (step S820). If it is determined that the road surface is in a frozen state, the control unit 20 Generates a selection screen for determining whether or not the driving support control can be performed on the frozen road surface (step S825). For example, it may be determined that the road surface is frozen when the surrounding area of the vehicle is snowing and the temperature is below a predetermined level based on weather information acquired by the communication unit.

  If it is not determined in step S820 that the road surface is frozen, the control unit 20 refers to the map information 30a to determine whether the road attribute is a mountain road (step S830), and is determined to be a mountain road. Then, the control unit 20 generates a selection screen for determining whether or not the driving support control on the mountain road is possible (step S835). If it is not determined in step S830 that the road attribute is a mountain road, the control unit 20 determines whether or not the road gradient ahead is a downhill exceeding a predetermined value (step S840), and a sudden increase exceeding the predetermined value is determined. If it is determined that the vehicle is a descending slope, a selection screen for determining whether or not the driving support control can be performed on the descending slope is generated (step S845).

  In the vehicle deceleration process in step S170 and the gear ratio selection process in step S180, as will be described in detail later, the characteristics of roads that are candidates for driving support control and the characteristics of roads around the host vehicle match. In addition, the deceleration control and the gear ratio control are performed only when the user selects to perform the driving support control by the driving support device in that case. Even if the road section has the same characteristics, it may or may not be desired to implement the driving support control depending on the user's feelings. Whether or not it can be performed can be selected each time, and driving support control can be performed only when the user makes a selection that he or she wants to perform.

(2-2) Vehicle deceleration processing:
FIG. 6 is a flowchart showing the vehicle deceleration process in step S170. In the vehicle deceleration process shown in FIG. 6, the control unit 20 determines whether the deceleration control state DS is “0” (step S200), whether it is “1” (step S210), and “2”. It is determined whether or not there is (step S220). If it is determined in step S200 that DS = 0, deceleration start determination processing (step S205), and if it is determined in step S210 that DS = 1, deceleration control processing (step S215), step S220 is performed. When it is determined that DS = 2, the vehicle speed limiting process (step S225) is executed. If it is another discrimination result and after steps S205, S215, and S225 are performed, the process returns to FIG. 3 and the process is repeated.

(2-3) Deceleration start determination process:
FIG. 7 is a flowchart showing the deceleration start determination process in step S205. In the deceleration start determination process, a process for setting the deceleration control state DS to “1” or “2” is performed based on a predetermined condition only when the user selects the execution of the driving support control. For this purpose, the control unit 20 first determines whether or not the host vehicle has reached a position at a predetermined distance from the start point Rs of the curve section Zr by the process of the deceleration control unit 21e4 (step S300). That is, the control unit 20 acquires the current position of the host vehicle based on an output signal from the GPS receiving unit 41 and the like, acquires the position of the start point Rs of the curve section Zr with reference to the curve section information 30a1, and It is determined whether or not the current position is a position opposite to the curve section Zr by a predetermined distance from the position of the start point Rs. If it is not determined in step S300 that the position has reached the predetermined distance from the start point Rs of the curve section Zr, the process after step S305 is skipped and the process returns to the process shown in FIG.

When it is determined in step S300 that the host vehicle has reached a position at a predetermined distance from the start point Rs of the curve section Zr, the control unit 20 performs the curve section by the processing of the vehicle speed information acquisition unit 21e1 and the deceleration control unit 21e4. A necessary deceleration Gr for setting the vehicle speed of the host vehicle to the target vehicle speed V ₀ at the start point Rs of Zr is acquired (step S305). That is, the control unit 20 acquires the vehicle speed when traveling a curve of the radius R at a constant speed with specifying the radius R of the curve zone Zr based on the curve zone information 30a1 as the target vehicle speed V _0. Further, the current position of the host vehicle specified based on the output signal from the GPS receiver 41 and the like, the end point Rs of the deceleration zone Zd specified based on the deceleration zone information 30a2 (start point of the curve zone), and the current The distance Lc is acquired from information indicating the position of the shape interpolation point between the position and the end point Rs. Then, the current vehicle speed Vc is specified based on the output information of the vehicle speed sensor 42, and the necessary deceleration Gr is acquired as Gr = (V ₀ ² −Vc ² ) / (2Lc).

  Next, the control unit 20 determines whether or not the user has selected to perform the driving support control in response to the guidance for selecting whether or not the driving support control can be performed by the guide unit 21c (step S310). If the execution of the driving support control is not selected, the deceleration start determination process is ended and the process returns to the process of FIG. 6. Only when the execution of the driving support control is selected, in order to start the deceleration control after step S315 move on.

  Next, the control unit 20 determines whether or not the throttle valve is in an open state (accelerator on state) (step S315). That is, the control unit 20 acquires the current throttle opening degree Th by the process of the deceleration control unit 21e4, and determines whether or not the throttle valve is in an open state. When it is not determined in step S315 that the throttle valve is in the open state (accelerator off state), the control unit 20 determines whether or not the required deceleration Gr is equal to or greater than the threshold LimG_L by the processing of the deceleration control unit 21e4 ( Step S320). When it is determined in step S315 that the throttle valve is in the open state (accelerator on state), the control unit 20 determines whether or not the required deceleration Gr is greater than or equal to the threshold LimG_h by the processing of the deceleration control unit 21e4. A determination is made (step S325).

When it is determined in steps S320 and S325 that the required deceleration Gr is equal to or greater than the respective threshold values, the control unit 20 sets the deceleration control state DS to “1” by the process of the deceleration control unit 21e4 (step S330). , S335). That is, when the host vehicle approaches the curve section Zr without decelerating, the necessary deceleration Gr for setting the vehicle speed to the target vehicle speed V ₀ increases as the host vehicle approaches the curve section Zr, and is reduced at any timing. Since the speed Gr exceeds the threshold value, the deceleration control state DS is set to “1” so that the deceleration control is performed after the threshold value is exceeded. In the present embodiment, the timing at which deceleration should be started differs depending on the state of the throttle valve, and the threshold values LimG_h and LimG_L when the throttle valve is in the open state and the closed state are set to different values, and LimG_h> LimG_L is set.

  On the other hand, when it is not determined in steps S320 and S325 that the required deceleration Gr is greater than or equal to the respective threshold values, the control unit 20 has reached the start point Rs of the curve section Zr by the processing of the deceleration control unit 21e4. Whether or not (step S340). That is, the current position of the host vehicle is acquired based on an output signal from the GPS receiver 41 and the like, the position of the start point Rs of the curve section Zr is acquired with reference to the deceleration section information 30a2, and the current position of the host vehicle is started. It is determined whether or not it is closer to the curve section Zr than the position of the point Rs. When it is determined in step S340 that the host vehicle has reached the start point Rs of the curve section Zr, the deceleration control state DS is set to “2” (step S345). That is, when the necessary deceleration Gr reaches the curve section Zr without exceeding the threshold value, the deceleration control state DS is set to “2”. If it is not determined in step S340 that the host vehicle has reached the end point Rs of the deceleration zone Zd, the process returns to the process shown in FIG.

(2-4) Deceleration control process:
FIG. 8 is a flowchart showing the deceleration control process in step S215. In the deceleration control process, a process for decelerating the host vehicle to the target vehicle speed V ₀ is performed. For this purpose, the control unit 20 first determines whether or not the start point Rs of the curve zone Zr (end point of the deceleration zone Zd) has been reached by the processing of the deceleration control unit 21e4 (step S400). That is, the control unit 20 acquires the current position of the host vehicle based on an output signal from the GPS receiving unit 41 and the like, acquires the position of the start point Rs of the curve section Zr with reference to the curve section information 30a1, and It is determined whether or not the current position of is closer to the curve section Zr than the position of the start point Rs.

When it is not determined in step S400 that the host vehicle has reached the starting point Rs of the curve section Zr, the control unit 20 performs the processing of the vehicle speed information acquisition unit 21e1 and the deceleration control unit 21e4 to start the starting point Rs of the curve section Zr. To obtain the necessary deceleration Gr for setting the vehicle speed of the host vehicle to the target vehicle speed V ₀ (step S405). This process is the same as that in step S305 described above.

  And the control part 20 generates the required deceleration Gr by an engine brake and a braking part (step S410). That is, the control unit 20 acquires the current gear ratio Sn and the current throttle opening Th by the processing of the deceleration control unit 21e4, and performs engine braking based on the engine speed at the gear ratio Sn and the throttle opening Th. To obtain the deceleration Ge. Then, the control unit 20 outputs a control signal for generating a deceleration corresponding to (Gr-Ge) to the braking unit 45 by the brake.

As a result, the braking unit 45 applies a brake so as to compensate for the difference (Gr−Ge) between the required deceleration Gr and the deceleration Ge, and the deceleration in the host vehicle becomes the required deceleration Gr. As described above, the required deceleration Gr is a required deceleration for setting the current vehicle speed Vc of the host vehicle to the target vehicle speed V ₀ at the distance Lc. Therefore, the vehicle speed of the host vehicle is reduced by repeating the above control. It can be converged to the target vehicle speed V ₀ . Note that the speed ratio in the above deceleration control is determined based on the required acceleration a instead of the required deceleration Gr, and the speed ratio of the host vehicle is changed to the acceleration speed ratio Sa at any point in the deceleration zone Zd by processing to be described later. Can be switched.

  When it is determined in step S400 that the host vehicle has reached the start point Rs of the curve section Zr, the control unit 20 sets the deceleration control state DS to “2” (step S415). That is, when the vehicle reaches the curve section Zr, the deceleration control state DS is set to “2” in order to perform the process of maintaining the vehicle speed instead of the deceleration. In addition, it returns to the process shown in FIG. 6 after step S410, S415.

(2-5) Vehicle speed limit processing:
FIG. 9 is a flowchart showing the vehicle speed limiting process in step S225. In the vehicle speed limiting process, a process for maintaining the vehicle speed of the host vehicle at the target vehicle speed V ₀ is performed. For this purpose, the control unit 20 first determines whether or not the end point Re (start point of the acceleration zone Za) of the curve zone Zr has been reached by the processing of the deceleration control unit 21e4 (step S500). That is, the control unit 20 acquires the current position of the host vehicle based on the output signal from the GPS receiving unit 41 and the like, acquires the position of the end point Re of the curve section Zr with reference to the curve section information 30a1, and It is determined whether or not the current position of is closer to the acceleration zone Za than the position of the end point Re.

When it is not determined in step S500 that the host vehicle has reached the end point Re of the curve section Zr, the control unit 20 specifies the current vehicle speed Vc based on the output information of the vehicle speed sensor 42 by the process of the deceleration control unit 21e4. and determines whether or not the current vehicle speed Vc exceeds the target vehicle speed V ₀ (step S505). If it is determined that the current vehicle speed Vc exceeds the V ₀ at step S505, the control unit 20 generates the required deceleration Gr using the engine brake and the braking portion (step S510). The processing in step S510 is the same as that in step S410 described above.

On the other hand, when it is determined in step S500 that the host vehicle has reached the end point Re of the curve section Zr, the control unit 20 sets the deceleration control state DS to “0” in order to end the deceleration control (step S515). ). After step S510, S515, and when it is not determined as the current vehicle speed Vc exceeds the V ₀ at step S505 and returns to the process shown in FIG.

(2-6) Gear ratio selection process:
FIG. 10 is a flowchart showing the gear ratio selection process in step S180. In the gear ratio selection process, a process for specifying the gear ratio control state GS and acquiring the acceleration gear ratio Sa and setting the gear ratio only when the user selects to perform the driving support control. Execute. In the gear ratio selection process, the control unit 20 determines whether or not the gear ratio control state GS is “0” (step S600) and “1” (step S615). When it is determined in step S600 that GS = 0, it is determined whether or not the user has selected to perform the driving support control with respect to the guidance for selecting whether or not the driving support control can be performed by the guide unit 21c. When it is determined that the user has selected to perform the driving support control (step S601), processing for setting the gear ratio control state GS to “1” (steps S605 and S610) is executed. If it is determined in step S615 that GS = 1, a gear ratio acquisition process (step S620) is executed.

  In step S605, the control unit 20 determines whether or not the current position of the host vehicle is within a predetermined distance to the start point Ca of the deceleration zone Zd by the process of the deceleration control unit 21e4. If it is not determined in step S605 that the current position of the host vehicle is within a predetermined distance from the start point Ca of the deceleration zone Zd, step S610 is skipped and the process returns to the process shown in FIG. On the other hand, when it is determined that the current position of the host vehicle is within a predetermined distance from the start point Ca of the deceleration zone Zd, the gear ratio control state GS is set to “1”. That is, GS = 1 which is a state for acquiring the acceleration gear ratio Sa before the deceleration zone Zd is set.

  The gear ratio acquisition process in step S620 will be described in detail later. In the gear ratio acquisition process, a value indicating the gear stage corresponding to the acceleration gear ratio Sa is substituted into a variable N indicating the gear stage corresponding to the gear ratio, Processing for changing the gear ratio control state GS to “2” is performed. In FIG. 10, when it is not determined that GS = 0 in step S600 and GS = 1 is not determined in step S615, that is, when the gear ratio control state GS is “2”, the control unit 20 Is set to travel at a gear ratio corresponding to the variable N by the processing of the gear ratio control unit 21e3 (step S630). Here, a value indicating the gear position corresponding to the acceleration gear ratio Sa is substituted for the variable N, and the control unit 20 outputs a control signal to the gear shift unit 44 to shift to the gear position indicated by the variable N.

  Next, the control unit 20 determines whether or not to maintain the state where the transmission gear ratio is set to the acceleration transmission gear ratio Sa by the processing of the transmission gear ratio control unit 21e3. That is, it is determined whether or not the end point Ce of the acceleration zone Za has been reached (step S635), whether or not the steering angle is within a predetermined angle (step S640), and the current vehicle speed is equal to or less than a predetermined value. Whether or not (step S645). If it is determined in step S635 that the end point Ce has been reached, if it is determined in step S640 that the steering angle is within a predetermined angle, it is determined in step S645 that the current vehicle speed is less than or equal to the predetermined value. When this is done, the control unit 20 sets the gear ratio control state GS to “0” (step S650). On the other hand, in other cases, step S650 is skipped.

  In the present embodiment, when the gear ratio control state GS becomes “0”, the state in which the gear ratio is set to the acceleration gear ratio Sa is canceled, and it is possible to perform a gear shift according to the driver's operation. Become. In step S635, the control unit 20 acquires the current position of the host vehicle based on the output signal from the GPS reception unit 41 and the like, and acquires the position of the end point Ce of the acceleration section Za with reference to the acceleration section information 30a3. Then, it is determined whether or not the current position of the host vehicle is after the position of the end point Ce. Therefore, before the host vehicle passes the end point Ce, it is considered that the state of the host vehicle can be accelerated with the acceleration gear ratio Sa set, and when the host vehicle passes the end point Ce, the driver The gear ratio can be set according to the operation.

  Furthermore, in step S640, the control unit 20 acquires output information of a steering angle sensor (not shown), and specifies a steering angle based on the output information. Then, it is determined whether or not the steering angle is within a predetermined angle by comparing the steering angle with a predetermined angle. Here, when the steering angle is within a predetermined angle, it is considered that acceleration can be performed with the acceleration gear ratio Sa being set, and when the steering angle is not within the predetermined angle, the speed change according to the driver's operation is performed. Make the ratio configurable.

  Further, in step S645, the control unit 20 specifies the current vehicle speed of the host vehicle based on the output information of the vehicle speed sensor 42, and determines whether or not the current vehicle speed is equal to or less than a predetermined value. Here, when the current vehicle speed is equal to or less than a predetermined value, the acceleration gear ratio Sa is considered to be a state where acceleration can be performed. When the current vehicle speed is not equal to or less than the predetermined value, the gear ratio according to the driver's operation is determined. Can be set.

(2-7) Gear ratio acquisition process:
FIG. 11 is a flowchart showing the gear ratio acquisition process in step S620. In the speed ratio acquisition process, a process for substituting the gear stage corresponding to the acceleration gear ratio Sa into N and setting the state (GS = 2) for switching to the gear stage corresponding to the acceleration gear ratio Sa is performed. Do.

In the gear ratio acquisition process, the control unit 20 substitutes the gear position corresponding to the acceleration gear ratio Sa for N (step S700). That is, the control unit 20 calculates the acceleration gear ratio Sa by the processing of the vehicle speed information acquisition unit 21e1, the necessary acceleration amount acquisition unit, and the acceleration gear ratio acquisition unit 21e2. Specifically, the control unit 20 specifies the target vehicle speed V ₀ based on the radius R of the curve section by the process of the vehicle speed information acquisition unit 21e1, and acquires the recommended vehicle speed V ₁ with reference to the acceleration section information 30a3.

The addition control unit 20 of the required acceleration obtaining unit process, identifies the distance L ₁ of the acceleration zone based on the acceleration zone information 30a3, the required acceleration a = a ^{_{(V 1 2 -V 0 2)}} / (2L 1) get. Further, the control unit 20 acquires the throttle opening degree Th ₁ at the start point Re of the acceleration zone Za by referring to the acceleration zone information 30a3 by the processing of the acceleration gear ratio acquisition unit 21e2, and the necessary acceleration a and the target vehicle speed V _0. Based on the above, the gear ratio is determined. In the present embodiment, when the vehicle speed of the host vehicle is the target vehicle speed V ₀ and the throttle opening Th ₁ , torques Tr _{1 to} Tr ₆ (1 to 6 correspond to the gear ratio) output at each gear ratio, The torque Tra corresponding to the required acceleration a is compared.

Therefore, first, the torque Tra corresponding to the required acceleration a is acquired as, for example, acceleration × vehicle weight × tire radius / differential gear ratio. On the other hand, the engine speed is realized by the gear ratio at the target vehicle speed V ₀ to (rpm), for example, target vehicle speed _{V 0 × 1000/3600 / (} 2π × tire radius) × differential gear ratio × 60 × gear ratio × Acquired as torque converter slip ratio. As a result, the engine speeds Re _{1 to} Re ₆ at the target vehicle speed V ₀ corresponding to the gear ratios 1 to 6 (speeds 6 to 1) are acquired. Further, torques Tr _{1 to} Tr ₆ that can be output at each engine speed Re _{1 to} Re ₆ and at the throttle opening Th ₁ are acquired. The torques Tr _{1 to} Tr ₆ are, for example, torques corresponding to the engine rotational speeds Re _{1 to} Re ₆ based on a torque characteristic map in which the throttle opening Th ₁ and the engine rotational speed are associated with the torque for each gear ratio. Tr _{1 to} Tr ₆ may be acquired.

As described above, when the torque Tra corresponding to the required acceleration a and the torques Tr _{1 to} Tr ₆ output at each gear ratio are acquired, the gear ratio at which the fuel consumption is minimized among the gear ratios exceeding the torque Tra. Is selected as the acceleration gear ratio Sa. As a result, the speed ratio at which the vehicle speed of the host vehicle can be set to the recommended vehicle speed V ₁ when acceleration is performed at the required acceleration a, and the speed ratio at which the fuel consumption is minimized is the acceleration speed ratio Sa. Become. When the acceleration gear ratio Sa is obtained, a value indicating the gear position corresponding to the acceleration gear ratio Sa is substituted into the variable N.

Further, after step S710, the control unit 20 performs a process for setting the speed ratio by setting the speed ratio control state GS to “2” at a timing for preventing a decrease in running stability of the vehicle. In this process, the control unit 20 calculates a deceleration force Fad acting on the host vehicle when the shift stage of the host vehicle is set to a shift stage corresponding to the acceleration gear ratio Sa (step S710). Here, the deceleration force Fad indicates a deceleration force (force directed toward the rear of the host vehicle) that acts on the host vehicle when traveling at the current vehicle speed and the current engine speed at the shift speed corresponding to the acceleration gear ratio Sa. Yes. The deceleration force Fad, for example, acquires torque corresponding to the gear position corresponding to the acceleration gear ratio Sa in the same manner as the calculation of the torques Tr _{1 to} Tr ₆ described above, and the deceleration based on the torque, vehicle weight, and the like. The force Fad may be calculated.

  Furthermore, the control part 20 performs the process for evaluating the force which causes a slip to the own vehicle. For this purpose, first, the control unit 20 acquires the curvature γ at a point two seconds ahead by the process of the transmission ratio control unit 21e3 (step S715). That is, the control unit 20 estimates a point when the vehicle travels for 2 seconds at the current vehicle speed, acquires at least three shape interpolation points or nodes closest to the point, and obtains at least three shape interpolation points. Alternatively, the curvature γ at the point is acquired based on the node. Further, the control unit 20 acquires the friction coefficient μ of the road surface at the point 2 seconds ahead (step S720). The friction coefficient μ of the road surface may be acquired from a road surface μ sensor, may be estimated based on weather, etc., and may be determined, or the friction coefficient may be determined using probe information. May be.

Next, the control unit 20 acquires a threshold LimFad for evaluating the force that causes the own vehicle to slip by the process of the transmission ratio control unit 21e3 (step S725). In this embodiment, the threshold LimFad is represented by ((μ · W · S) ² −Fc (γ) ² ) ^1/2 , W is the weight of the host vehicle, S is a coefficient greater than 0 and less than 1, Fc (γ ) Is a function indicating the lateral force acting on the host vehicle when traveling at a curvature γ. Note that the weight W, the coefficient S, and the function Fc (γ) are recorded in the recording medium 30 in advance, and the control unit 20 refers to the recording medium 30 to acquire such information and calculates the threshold LimFad.

  FIG. 12 is an explanatory diagram for explaining the deceleration force Fad and the threshold LimFad. In FIG. 12, the host vehicle C traveling toward the arrow Fw and the magnitude of the frictional force μ · W acting on the host vehicle C are indicated by solid circles. In FIG. 12, slip occurs in the host vehicle C when the tip of a vector indicating the force acting on the host vehicle C (the resultant force of the lateral force Fc (γ) and the deceleration force) exceeds the solid circle. That is, if the frictional force μ · W is divided into a lateral force Fc (γ) and a deceleration force toward the rear of the vehicle, the deceleration force can be regarded as a limit deceleration force that causes slip.

  Therefore, in this embodiment, a constant margin is given to the frictional force μ · W, and the value μ · W · S obtained by multiplying the frictional force μ · W by a coefficient S of 1 or less is used as the lateral force Fc (γ ), The value obtained by dividing the force toward the rear of the vehicle is defined as the threshold LimFad. That is, as illustrated in FIG. 12, when the tip of the vector indicating the deceleration force Fad is closer to the outer periphery of the circle than the position P corresponding to the tip of the component force vector of the vector μ · W · S, It is assumed that the running stability is reduced.

  For this reason, the control unit 20 determines whether or not the deceleration force Fad is larger than the threshold value LimFad (step S730). If it is not determined that the deceleration force Fad is larger than the threshold value LimFad, the control unit 20 It is determined whether or not the point has exceeded the start point Rs of the curve section Zr (step S735). If it is not determined that the point has exceeded the start point Rs, the process returns to the process shown in FIG. On the other hand, when it is determined in step S730 that the deceleration force Fad is larger than the threshold LimFad, or when it is determined in step S735 that the point 2 seconds ahead exceeds the start point Rs of the curve section Zr, Is set to “2” (step S740).

  Therefore, when the gear ratio control state GS becomes “2” after step S730 and further the process of setting the gear ratio is performed in step S630 after the determination in step S615, the force acting on the host vehicle is applied to the host vehicle. The gear ratio is set to the acceleration gear ratio Sa before the slip generation force is generated. Therefore, by setting the transmission gear ratio to the acceleration transmission gear ratio Sa, the transmission gear ratio can be set so that the own vehicle does not slip, and the transmission gear ratio can be set while suppressing the influence of the gear shifting on the behavior of the vehicle. Is possible. Here, it is only necessary to evaluate whether or not the force acting on the host vehicle in front of the host vehicle is a force that causes slipping, and as described above, a time point after a predetermined time interval from the current time point. In addition to the configuration for evaluating the force at, a configuration for evaluating the force at a position ahead by a predetermined distance from the current position may be adopted. Note that “2 seconds” in step S715 and step S735 is an example, and after the transmission ratio control unit 21d outputs a control signal for setting the transmission ratio to the acceleration transmission ratio Sa to the transmission unit 44, the control signal Accordingly, it is only necessary to set a value larger than the time required until the change of the gear ratio by the transmission unit 44 is completed. For example, in step S735, it is sufficient if the speed ratio can be switched to the acceleration speed ratio Sa before the host vehicle reaches the start point Rs. Of course, in order to evaluate the force at a time point after a predetermined time interval from the current time point, when the force at a position ahead by a predetermined distance from the current position is adopted as described above, the gear shift is performed at the current position. It is possible to adopt a configuration in which a predetermined distance is greater than the distance from the start of the process to the completion of the shift.

According to the above processing, for example, as shown by a thick dashed arrow in FIG. 2, when the host vehicle C traveling at the 6th speed on the road before reaching the deceleration zone Zd approaches the curve zone Zr, the vehicle is decelerated. Before reaching the start point Ca of the zone Zd, a screen for allowing the user to select whether or not to perform the driving support control is displayed. When the user selects execution, the deceleration control is performed and the target is reached by the end point Rs of the deceleration zone Zd. It is the vehicle speed V _0. In the deceleration zone Zd, the acceleration gear ratio Sa is calculated in the gear ratio acquisition process. In the gear ratio acquisition process, the curvature γ of the road two seconds ahead of the host vehicle C is acquired, and when the γ increases and the deceleration force Fad exceeds the threshold LimFad, the deceleration control state GS is “ Since the acceleration gear ratio Sa is, for example, the gear ratio corresponding to the third gear, the speed is changed to the third gear by the process of step S630. Accordingly, as indicated by the thick dashed line in FIG. 2, the gear stage is maintained at the third speed in the subsequent deceleration zone Zd, curve zone Zr, and acceleration zone Za, and smooth when acceleration is started in the acceleration zone Za. Can be accelerated.

(3) Other embodiments:
The above embodiment is an example for carrying out the present invention. When the feature information includes a feature that matches the feature indicated in the candidate feature information, the user is allowed to select whether or not to perform the driving support control. However, if the driver selects to permit the execution of the driving support control, various other embodiments can be adopted as long as the driving support control is performed. For example, the target vehicle speed is calculated from the radius R of the curve section Zr, but it is of course possible to associate the target vehicle speed with each curve section in advance and acquire the associated target vehicle speed. Furthermore, the application target of the present invention is not limited to the curve section, and the present invention may be applied to a road with a slope. For example, if a section including a gradient is defined as a gradient section, and the target vehicle speed when the host vehicle reaches the gradient section and the recommended vehicle speed after traveling in the gradient section are defined, the required acceleration amount is the same as in the above configuration. The acceleration gear ratio can be acquired and the acceleration gear ratio can be set in advance at the stage before the gradient section. In this configuration, the target vehicle speed can be defined as a vehicle speed at which the vehicle speed is reduced to a preferable vehicle speed for traveling in the down-gradient section until the start point of the down-gradient.

  Further, the present invention is not limited to the configuration for acquiring the gear ratio corresponding to the required acceleration amount, and may be various as long as the gear ratio capable of accelerating to a vehicle speed higher than the target vehicle speed can be determined. A configuration can be adopted. For example, the number of revolutions of the drive source (engine or motor) corresponding to the throttle opening / closing operation after traveling a predetermined section such as a curve section is learned in advance, and the learned rotation is performed after traveling the predetermined section on the own vehicle. It is possible to adopt a configuration that identifies the acceleration gear ratio for rotating the drive source by a number and accelerating from the target vehicle speed to a higher vehicle speed. That is, even when the recommended vehicle speed is not specified, various configurations can be employed as long as the vehicle speed of the host vehicle can be accelerated to a vehicle speed higher than the target vehicle speed after traveling in a predetermined section.

  Furthermore, the acceleration gear ratio may be at least a gear ratio necessary and sufficient for accelerating to a vehicle speed higher than the target vehicle speed, but a gear ratio for smoothing acceleration may be determined in advance. For example, it is possible to estimate parameters such as the throttle opening / closing operation at the start of acceleration and the rotational speed of the vehicle drive source, and to select a gear ratio that can be most efficiently accelerated based on the estimation. Further, in the deceleration control, a configuration in which feedback control is performed based on the deceleration as described above, or feedback control based on the vehicle speed may be employed.

  Furthermore, the required acceleration amount may be a parameter for evaluating energy output from the host vehicle in order to change the vehicle speed from the target vehicle speed to the recommended vehicle speed, and is not limited to the above-described required acceleration a. For example, torque, engine output, etc. can be employed. Furthermore, in the above-described embodiment, the deceleration zone Zd and the acceleration zone Za are the clothoid zones, but it is needless to say that these zones may be determined in advance as a zone for deceleration and a zone for acceleration, respectively. It may be shorter or longer than the clothoid interval. Furthermore, it may not be a clothoid section, and for example, a predetermined section between a curve section and a next curve section when the curve sections continue may be used as an acceleration section. Further, the shift to the acceleration gear ratio may be performed before reaching the predetermined section, the shift may be performed at the start point or the end point of the predetermined section, and the required deceleration Gr exceeds the thresholds LimG_h and LimG_L. The speed may be changed at the time, and various configurations can be adopted.

In the above-described embodiment, the deceleration control is performed when the required deceleration Gr exceeds the thresholds LimG_h and LimG_L. Of course, other configurations, for example, pass through the start point Ca of the deceleration zone Zd. It is good also as a structure which starts deceleration after doing. Further, the vehicle speed limiting processing, it is configured to perform deceleration when the current vehicle speed Vc exceeds the target vehicle speed V _0, may be configured to perform the acceleration when the current vehicle speed Vc falls below the threshold value V _0. Furthermore, in the above-described embodiment, the speed ratio with the smallest fuel consumption is selected as the speed ratio Sa, among the speed ratios that can output more than the torque Tra corresponding to the required acceleration a. The acceleration gear ratio may be determined based on the idea. For example, the torque Tra corresponding to the required acceleration a and the torques Tr _{1 to} Tr ₆ output at each gear ratio may be acquired, and the smallest gear ratio among the gear ratios exceeding the torque Tra may be set as the acceleration gear ratio Sa. .

In other words, the engine speed corresponding to the throttle opening Th ₁ is a gear ratio that allows the vehicle speed of the host vehicle to be the recommended vehicle speed V ₁ when accelerating at the required acceleration a while maintaining the gear ratio. The speed ratio at which the degree of decrease in the rotational speed when the number is decreased and transmitted to the output side is the acceleration speed ratio Sa. According to this configuration, the host vehicle can be accelerated from the target vehicle speed V ₀ to the recommended vehicle speed V ₁ without increasing the engine speed as much as possible, and acceleration can be performed efficiently. Although the engine speed corresponding to the throttle opening degree Th ₁ is assumed here, it is needless to say that the speed may be determined based on a statistical value or the like.

  The driving support control performed by the driving support control means is not limited to the contents described in the above embodiment, and various controls for supporting the driving operation of the user can be applied. For example, the driving support control may be a control for decelerating the host vehicle, a control for switching the speed ratio of the host vehicle, or a control for performing guidance for prompting a deceleration or a shift.

  Further, the guidance means may provide guidance by voice. In this case, the selection information acquisition unit may analyze a voice uttered by the user and acquire information indicating whether the user can select. Further, the guidance means may guide the user by emphasizing buttons, switches, and the like. For example, changing the backlight state of buttons and switches provided at positions that can be operated by the user sitting in the driver's seat (for example, the instrument panel or the steering operation unit) (changing from the unlit state to the lit state or blinking state) ) May be employed. In this case, the selection information acquisition unit acquires information indicating whether the operation for the button or switch is feasible.

In addition to the above-described embodiment, the road features that are candidates for driving support control include, for example, a road with a poor forward view due to the presence of an obstacle, and a curve curvature that is greater than a predetermined value. Roads and the like may be included.
Further, in the driving support control means of the above embodiment, when the user selects to allow the driving support control, the same driving support control is performed regardless of the characteristics of the road. The control content of the driving support control may be changed according to the characteristics of the. For example, when the road feature is a frozen road surface, the threshold value used in steps S320 and S325 may be lowered. Further, for example, when the road feature is a wet road surface, only shifting may be performed without performing deceleration by the braking unit.

It is a block diagram of the navigation apparatus containing a driving assistance device. It is a figure which shows the example of a curve area. It is a flowchart of a driving assistance process. It is a flowchart of guidance implementation determination processing. It is a figure which shows an example of the implementation selection screen of driving assistance control. It is a flowchart of a vehicle deceleration process. It is a flowchart of a deceleration start determination process. It is a flowchart of a deceleration control process. It is a flowchart of a vehicle speed restriction process. It is a flowchart of a gear ratio selection process. It is a flowchart of a gear ratio acquisition process. It is explanatory drawing explaining the force which acts on a vehicle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Navigation apparatus, 20 ... Control part, 21 ... Navigation program, 21a ... Feature information acquisition part, 21b ... Candidate feature information acquisition part, 21c ... Guide part, 21d ... Selection information acquisition part, 21e ... Driving support control part, 21e1 ... Vehicle speed information acquisition unit, 21e2 ... Acceleration gear ratio acquisition unit, 21e3 ... Gear ratio control unit, 21e4 ... Deceleration control unit, 21e5 ... Acceleration control unit, 30 ... Recording medium, 30a ... Map information, 30a1 ... Curve section information, 30a2 ... deceleration section information, 30a3 ... acceleration section information, 30b ... candidate feature information, 41 ... GPS receiving section, 42 ... vehicle speed sensor, 43 ... gyro sensor, 44 ... shift section, 45 ... braking section, 46 ... throttle control section, 47 ... Camera, 48 ... User I / F section

Claims (4)

Characteristic information acquisition means for acquiring characteristic information indicating characteristics of a road around the host vehicle;
Candidate feature information means for obtaining candidate feature information indicating a feature of a road as a candidate for carrying out driving support control;
When a feature that matches the feature indicated in the candidate feature information is included in the feature information, guidance means for guiding the user to select whether or not the driving support control can be performed;
Selection information acquisition means for acquiring information indicating the user's selection;
Driving support control means for performing the driving support control when the user selects to permit the execution of the driving support control;
A driving support apparatus comprising: The driving support control means includes
A vehicle speed information acquisition unit for acquiring a target vehicle speed when traveling in a predetermined section ahead of the host vehicle;
An acceleration gear ratio acquisition unit that acquires an acceleration gear ratio that is a gear ratio for accelerating the host vehicle to a vehicle speed greater than the target vehicle speed after traveling the predetermined section;
A speed ratio control unit that sets the speed ratio of the host vehicle to the acceleration speed ratio before reaching the start point of the predetermined section;
A deceleration control unit that decelerates the vehicle speed of the host vehicle to the target vehicle speed before reaching the start point of the predetermined section;
The driving support device according to claim 1, comprising: A feature information acquisition step for acquiring feature information indicating characteristics of a road around the host vehicle;
A candidate feature information step for obtaining candidate feature information indicating a feature of a road as a candidate for carrying out driving support control;
When the feature information includes a feature that matches the feature indicated in the candidate feature information, a guidance step for guiding the user to select whether or not to perform the driving support control; and
A selection information acquisition step of acquiring information indicating the user's selection;
A driving support control step for performing the driving support control when the user selects to permit the driving support control;
Driving support method including. A feature information acquisition function for acquiring feature information indicating features of roads around the host vehicle;
A candidate feature information function for obtaining candidate feature information indicating features of a road as a candidate for performing driving support control;
When the feature information includes a feature that matches the feature indicated in the candidate feature information, a guidance function for guiding the user to select whether or not the driving support control can be performed;
A selection information acquisition function for acquiring information indicating the user's selection;
A driving support control function for performing the driving support control when the user selects to permit the execution of the driving support control;
Driving support program that realizes the computer.

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