Vehicle driving assistance system

Abstract

To provide a vehicle driving assistance apparatus which can control a deceleration of a vehicle to a suitable deceleration when the vehicle travels on a curved road.SOLUTION: When an own vehicle 100 is traveling on a curved road and a moving speed of the own vehicle is greater than a target speed, a vehicle driving assistance apparatus 10 executes speed control of controlling the moving speed of the own vehicle to the target speed or less. When executing the speed control and an own vehicle moving course being a course of the own vehicle to a destination a predetermined distance away from the own vehicle, is within a drivable area of the curved road, the vehicle driving assistance apparatus controls deceleration of the own vehicle by the speed control to be smaller than deceleration of when the own vehicle moving course is out of an outer boundary of the drivable area.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a vehicle driving support device.

Background Art

[0002] There is known a vehicle driving support device that sets an appropriate vehicle speed or deceleration as a target speed or target deceleration based on the curvature of a curved road so that the vehicle travels on the curved road at an appropriate vehicle speed, and controls the vehicle speed or deceleration so that the vehicle speed becomes less than or equal to the target speed or the deceleration becomes equal to the target deceleration (see, for example, Patent Document 1).

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

[0004] In the above-described conventional vehicle driving support device, the target speed or target deceleration is set based on the curvature of the curved road. However, the actual travel path of the vehicle varies depending on the steering angle of the vehicle even at the same vehicle speed. Therefore, when the vehicle speed or deceleration is controlled using the target speed or target deceleration set based on the curvature of the curved road, the deceleration of the vehicle may not be an appropriate deceleration for traveling on the curved road.

[0005] An object of the present invention is to provide a vehicle driving support device capable of controlling the deceleration of a vehicle to an appropriate deceleration when the vehicle travels on a curved road.

[0006] The vehicle driving support device according to the present invention includes a control device that executes speed control for controlling the travel speed of the host vehicle to be less than or equal to a target speed when the travel speed of the host vehicle is greater than the target speed while the host vehicle is traveling on a curved road. When executing the speed control, the control device determines the travel path of the host vehicle from the host vehicle to a predetermined distance ahead. and the predicted path the vehicle will travelWhen the vehicle's path is within the range of the curved road, the speed control is configured to reduce the deceleration of the vehicle compared to when the vehicle's path is outside the outer boundary of the range. Furthermore, the control device is configured to set the predetermined distance to a longer distance the smaller the curvature of the curved road.

[0007] According to the vehicle driving assistance system of the present invention, the degree of deceleration of the vehicle by speed control is determined according to the actual path the vehicle is traveling. Therefore, when the vehicle is traveling on a curved road, the deceleration of the vehicle can be controlled to an appropriate level.

[0009] Furthermore, According to the vehicle driving support device of the present invention, the degree of deceleration of the vehicle by speed control can be determined according to the curvature of the curved road.

[0010] Furthermore, in the vehicle driving support device according to the present invention, the control device may be configured such that, when the vehicle's path is outside the outer boundary of the road range during the execution of the speed control, the shorter the distance between the point where the vehicle's path goes outside the outer boundary of the road range and the vehicle, the stronger the deceleration of the vehicle by the speed control.

[0011] According to the vehicle driving support device of the present invention, the degree of deceleration of the vehicle by speed control can be determined according to the distance between the vehicle and the point where the vehicle's path goes outside the outer boundary of the driving range.

[0012] Furthermore, in the vehicle driving support device according to the present invention, the control device may be configured to set the target speed when executing the speed control, set the target deceleration, which is the target value of the degree of deceleration of the vehicle when the vehicle is decelerated so that the vehicle's driving speed is controlled to be below the target speed, set the target deceleration increase rate, which is the target value of the rate at which the degree of deceleration of the vehicle increases, and set the target deceleration support start timing, which is the target value of the timing at which the vehicle starts to decelerate, and execute the speed control according to these target speed, target deceleration, target deceleration increase rate, and target deceleration support start timing. In this case, the control device may be configured to reduce the deceleration of the vehicle due to the speed control by performing at least one of the following correction processes when the vehicle's path is within the track range: a correction process to correct the target speed so that it is greater than when the vehicle's path is outside the outer boundary of the track range; a correction process to correct the target deceleration so that it is smaller; a correction process to correct the target deceleration rate so that it is smaller; and a correction process to correct the target deceleration support start timing so that the target deceleration support start timing is delayed.

[0013] According to the vehicle driving support device of the present invention, the deceleration of the vehicle due to speed control can be weakened by correcting the target speed, target deceleration, target deceleration increase speed, and target deceleration support start timing.

[0014] The components of the present invention are not limited to the embodiments described below with reference to the drawings. Other objects, features, and incidental advantages of the present invention will be readily apparent from the description of the embodiments. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is a diagram showing a vehicle driving assistance device according to an embodiment of the present invention. [Figure 2]Figure 2 is a flowchart showing the routine executed by a vehicle driving assistance device according to an embodiment of the present invention. [Figure 3] Figure 3 shows the curve distance and other related information. [Figure 4] Figure 4(A) shows a scenario where the vehicle's path is within the road area, while Figure 4(B) shows a scenario where the vehicle's path extends beyond the left boundary (outer boundary) of the road area. [Modes for carrying out the invention]

[0016] Hereinafter, a vehicle driving support device according to an embodiment of the present invention will be described with reference to the drawings. Figure 1 shows a vehicle driving support device 10 according to an embodiment of the present invention. The vehicle driving support device 10 is mounted on the vehicle 100. Hereinafter, the vehicle driving support device 10 will be described using the case where the operator of the vehicle 100 is a person who is riding in the vehicle 100 and driving the vehicle 100 (i.e., the driver of the vehicle 100) as an example.

[0017] However, the operator of the vehicle 100 may be a person who operates the vehicle 100 remotely without being in the vehicle 100 (i.e., a remote operator of the vehicle 100). If the operator of the vehicle 100 is a remote operator, the vehicle driving support device 10 is installed in the vehicle 100 and in the remote control equipment installed outside the vehicle 100 for remote operation of the vehicle 100, and the functions of the vehicle driving support device 10 described below are shared between the vehicle driving support device 10 installed in the vehicle 100 and the vehicle driving support device 10 installed in the remote control equipment.

[0018] As shown in FIG. 1, the vehicle driving support device 10 includes an ECU (Electronic Control Unit) 90 as a control device. The ECU 90 includes a microcomputer as a main part. The microcomputer includes a CPU, a ROM, a RAM, a storage medium such as a non-volatile memory, and an interface, etc. The CPU realizes various functions by executing instructions, programs, or routines stored in the storage medium. In particular, in this example, the vehicle driving support device 10 stores a program for realizing various controls executed by the vehicle driving support device 10 in the storage medium.

[0019] In addition, the vehicle driving support device 10 may be configured to be able to update (update) the program stored in the storage medium by wireless communication (for example, Internet communication) with an external device.

[0020] Moreover, the present invention is applicable to any of a vehicle that can be driven by manual driving operation and automatic driving control, a vehicle that can be driven only by manual driving operation, and a vehicle that can be driven only by automatic driving control. The manual driving operation is a driving operation performed by the operator himself / herself to drive the vehicle. The automatic driving control is a control in which a control device such as an ECU automatically drives the vehicle without the operator himself / herself performing the driving operation for driving the vehicle.

[0021] The host vehicle 100 is equipped with a driving device 21 and a braking device 22.

[0022] The driving device 21 is a device that generates a driving force applied to the host vehicle 100 to drive the host vehicle 100, and includes, for example, an internal combustion engine and / or an electric motor. The driving device 21 is electrically connected to the ECU 90. The vehicle driving support device 10 can control the driving force applied to the host vehicle 100 by controlling the operation of the driving device 21.

[0023] The braking device 22 is a device that generates the braking force applied to the host vehicle 100 to brake the host vehicle 100, and for example, includes a hydraulic braking device. The braking device 22 is electrically connected to the ECU 90. The vehicle driving support device 10 can control the braking force applied to the host vehicle 100 by controlling the operation of the braking device 22.

[0024] Furthermore, the host vehicle 100 is equipped with an accelerator pedal operation amount sensor 31, a brake pedal operation amount sensor 32, a vehicle speed detection device 33, a steering angle sensor 34, a yaw rate sensor 35, and an acceleration sensor 36.

[0025] The accelerator pedal operation amount sensor 31 is a sensor that detects the depression amount of the accelerator pedal of the host vehicle 100 by the driver. The accelerator pedal operation amount sensor 31 is electrically connected to the ECU 90. The vehicle driving support device 10 acquires the operation amount of the accelerator pedal as the accelerator pedal operation amount AP by the accelerator pedal operation amount sensor 31.

[0026] The brake pedal operation amount sensor 32 is a sensor that detects the depression amount of the brake pedal of the host vehicle 100 by the driver. The brake pedal operation amount sensor 32 is electrically connected to the ECU 90. The vehicle driving support device 10 acquires the operation amount of the brake pedal as the brake pedal operation amount BP by the brake pedal operation amount sensor 32.

[0027] The vehicle speed detection device 33 is a device that detects the traveling speed of the host vehicle 100, and for example, is a wheel speed sensor. The vehicle speed detection device 33 is electrically connected to the ECU 90. The vehicle driving support device 10 acquires the traveling speed of the host vehicle 100 as the host vehicle speed V by the vehicle speed detection device 33.

[0028] The steering angle sensor 34 is a sensor that detects the rotation angle of the steering wheel of the vehicle 100 relative to the neutral position. The steering angle sensor 34 is electrically connected to the ECU 90. The vehicle driving assistance system 10 obtains the rotation angle of the steering wheel using the steering angle sensor 34 and obtains the steering angle of the steering wheels of the vehicle 100 as the steering angle θ based on the obtained rotation angle.

[0029] The yaw rate sensor 35 is a sensor that acquires the yaw rate of the vehicle 100. The yaw rate sensor 35 is electrically connected to the ECU 90. The vehicle driving assistance system 10 acquires the yaw rate of the vehicle 100 as yaw rate Y using the yaw rate sensor 35.

[0030] The acceleration sensor 36 is a sensor that detects the acceleration of the vehicle 100 in the longitudinal direction. The acceleration sensor 36 is electrically connected to the ECU 90. The vehicle driving support system 10 acquires the acceleration of the vehicle 100 as acceleration G using the acceleration sensor 36.

[0031] Furthermore, the vehicle 100 is equipped with a surrounding information detection device 40 and a road information detection device 50.

[0032] The surrounding information detection device 40 is a device that detects information about the surroundings of the vehicle 100, and in this example, it is equipped with an image sensor 41 and an electromagnetic wave sensor 42.

[0033] The image sensor 41 is a sensor that captures images of the area around the vehicle 100 and acquires images of the area around the vehicle 100, and is, for example, a camera. The image sensor 41 is electrically connected to the ECU 90. The vehicle driving support system 10 acquires images of the area around the vehicle 100 (surrounding image) as surrounding detection information IFsur using the image sensor 41.

[0034] The electromagnetic wave sensor 42 is a sensor that detects objects present in the vicinity of the vehicle 100, and is, for example, a radio wave sensor such as a radar sensor (millimeter-wave radar, etc.), a sound wave sensor such as an ultrasonic sensor (clearance sonar), and an optical sensor such as a laser radar (LiDAR). The electromagnetic wave sensor 42 is electrically connected to the ECU 90. The vehicle driving support system 10 acquires information about objects in the vicinity of the vehicle 100 (target information) as ambient detection information IFsur using the electromagnetic wave sensor 42.

[0035] The road information detection device 50 is a device that acquires information about the road (vehicle travel road RD) on which the vehicle 100 is traveling, and in this example, it includes a GPS device 51 and a map information database 52.

[0036] The GPS device 51 is a device that receives so-called GPS signals. The GPS device 51 is electrically connected to the ECU 90. The vehicle driving assistance system 10 acquires GPS signals via the GPS device 51 and obtains information indicating the current position of the vehicle 100 as current position information IFpos based on the acquired GPS signals.

[0037] The map information database 52 is a database that stores map information, including information about roads. The map information database 52 is electrically connected to the ECU 90. The vehicle driving assistance system 10 obtains information about the road RD on which the vehicle is traveling as road information IFroad from the map information database 52 based on the current location information IFpos of the vehicle 100.

[0038] <Operation of vehicle driver assistance system> Next, the operation of the vehicle driving support system 10 will be explained. The vehicle driving support system 10 executes the routine shown in Figure 2 at a predetermined calculation cycle, and when the vehicle 100 is traveling on a curved road CR (see Figure 3) and its speed is greater than the target speed, it performs speed control to control the vehicle 100's speed to be below the target speed.

[0039] When a predetermined timing occurs, the vehicle driving support device 10 starts processing from step S200 of the routine shown in Figure 2, proceeds to step S205, and acquires curve characteristic information INcurve.

[0040] The curve characteristic information INcurve is information about the curved road CR on which the vehicle 100 is traveling, and in this example, it is the curve curvature C and the curve distance Dcurve.

[0041] The curve curvature C is the curvature of the curved road CR on which the vehicle 100 is traveling, and in this example, it is obtained based on the surrounding detection information IFsur and / or road information IFroad.

[0042] The curve distance Dcurve is the distance of the curved road CR that the vehicle 100 is traveling on (see Figure 3), and in this example, it is obtained based on the surrounding detection information IFsur and / or road information IFroad.

[0043] Next, the vehicle driving support system 10 proceeds to step S210 and acquires the vehicle driving characteristic information IFmove.

[0044] The vehicle driving characteristics information IFmove is information about the driving state of the vehicle 100, and in this example, it is the vehicle speed V and yaw rate Y.

[0045] Next, the vehicle driving support system 10 proceeds to step S215 to set the target deceleration characteristics.

[0046] The target deceleration characteristics are those that determine the strength (magnitude) of the deceleration of the vehicle 100. In this example, these are the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, and target deceleration support start timing Tstart.

[0047] The target speed Vtgt is the target value for the vehicle's speed (vehicle speed V), and in this example, it is set based on the curve curvature C. In particular, the larger the curve curvature C, the smaller the value set.

[0048] The target deceleration Gdec_tgt is the target value for the deceleration of the vehicle 100. In this example, it is set based on the target speed Vtgt, the vehicle speed V, and the curve distance Dcurve. In particular, when the vehicle speed V is greater than the target speed Vtgt, the larger the difference between the vehicle speed V and the target speed Vtgt, the larger the value set. The shorter the curve distance Dcurve, the larger the value set.

[0049] The target jerk value dGdec_tgt is the target value of the amount of increase per unit time (deceleration increase rate) when increasing the deceleration Gdec of the vehicle 100 to the target deceleration Gdec_tgt. In this example, it is set based on at least one of the following: the difference between the deceleration Gdec of the vehicle 100 and the target deceleration Gdec_tgt, the vehicle speed V, and the curve curvature C. In particular, the larger the difference between the deceleration Gdec of the vehicle 100 and the target deceleration Gdec_tgt, the larger the value set; the larger the vehicle speed V, the smaller the value set; and the larger the curve curvature C, the smaller the value set. However, the target jerk value dGdec_tgt may also be set to a constant value, regardless of the difference between the deceleration Gdec of the vehicle 100 and the target deceleration Gdec_tgt, the vehicle speed V, and the curve curvature C.

[0050] The target deceleration support start timing Tstart is the target value for the timing at which the deceleration of the vehicle 100 begins to increase towards the target deceleration Gdec_tgt (the timing at which the vehicle 100 begins to decelerate). In this example, it is set based on the difference between the deceleration Gdec of the vehicle 100 and the target deceleration Gdec_tgt, the vehicle speed V, and the curve curvature C. In particular, the larger the difference between the deceleration Gdec of the vehicle 100 and the target deceleration Gdec_tgt, the earlier the timing is set; the larger the vehicle speed V, the earlier the timing is set; and the larger the curve curvature C, the earlier the timing is set. However, the target deceleration support start timing Tstart may also be set to a constant value, regardless of the difference between the deceleration Gdec of the vehicle 100 and the target deceleration Gdec_tgt, the vehicle speed V, and the curve curvature C.

[0051] Next, the vehicle driving support device 10 proceeds to step S220 to acquire the road range RM.

[0052] The road range RM is the area (road) in which the vehicle 100 can travel on a curved road CR, and in the example shown in Figure 3, it corresponds to the range of the vehicle's driving lane LN. The vehicle's driving lane LN is the lane demarcated by a white line or other lane marking on the left side of the vehicle 100 (left boundary MBleft) and a white line or other lane marking on the right side of the vehicle 100 (right boundary MBright). In this example, the road range RM is obtained based on the surrounding detection information IFsur and / or road information IFroad.

[0053] Next, the vehicle driving support system 10 proceeds to step S225 and acquires the vehicle's path MC.

[0054] The vehicle's path MC is the path taken by the vehicle 100 from its current location to a predetermined distance (predetermined travel distance Dmove_th). In other words, the vehicle's path MC is the path that the vehicle 100 is expected to take until it has traveled the predetermined travel distance Dmove_th. In this example, the vehicle's path MC is obtained based on the vehicle's speed V, yaw rate Y, and steering angle θ. The predetermined travel distance Dmove_th may be a constant value, or it may be set to a shorter distance as the curve curvature C increases.

[0055] Next, the vehicle driving support device 10 proceeds to step S230 and determines whether or not the road condition Cin is met.

[0056] The track condition Cin is the condition that the vehicle's path MC, obtained in step S225, is within the track range RM obtained in step S220, or is outside the inner boundary MBin of the track range RM. The inner boundary MBin of the track range RM is the boundary that defines the inside of the curved road CR. For example, in the curved road CR shown in Figure 2, the inner boundary MBin of the track range RM is the right boundary MBright. Also, in the following explanation, the outer boundary MBout of the track range RM is the boundary that defines the outside of the curved road CR. For example, in the curved road CR shown in Figure 2, the outer boundary MBout of the track range RM is the left boundary MBleft.

[0057] For example, in the curved road CR shown in Figure 3(A), if the vehicle's path MC does not cross either the left boundary MBleft, which is the outer boundary MBout of the road range RM, or the right boundary MBright, which is the inner boundary MBin of the road range RM, then the vehicle's path MC is within the road range RM, and therefore the road condition Cin is met.

[0058] In particular, in this example, if the outer lateral distance Wout and the inner lateral distance Win are greater than or equal to the predetermined lateral distance Wth at all points on the vehicle's path MC, then the road condition Cin is determined to be met. In the curved road CR shown in Figure 3(A), if the left lateral distance Wleft (outer lateral distance Wout) and the right lateral distance Wright (inner lateral distance Win) are greater than or equal to the predetermined lateral distance Wth at all points on the vehicle's path MC, then the road condition Cin is determined to be met.

[0059] Furthermore, the outer lateral distance Wout is the distance between the vehicle's path MC and the outer boundary MBout in the width direction of the curved road CR, and the inner lateral distance Win is the distance between the vehicle's path MC and the inner boundary MBin in the width direction of the curved road CR. Therefore, the left lateral distance Wleft is the distance between the vehicle's path MC and the left boundary MBleft in the width direction of the curved road CR, and the right lateral distance Wright is the distance between the vehicle's path MC and the right boundary MBright in the width direction of the curved road CR. In addition, the predetermined lateral distance Wth is set to a value greater than or equal to zero.

[0060] Furthermore, in the curved road CR shown in Figure 3(A), if the vehicle's path MC crosses the right-side boundary MBright, which is the inner boundary MBin of the road range RM, then the vehicle's path MC is outside the inner boundary MBin of the road range RM, and therefore the road condition Cin is determined to be met. In particular, in this example, if the inner lateral distance Win is smaller than the predetermined lateral distance Wth at any point on the vehicle's path MC, then the road condition Cin is determined to be met. In the curved road CR shown in Figure 3(A), if the right-side lateral distance Wright, which is the inner lateral distance Win, is smaller than the predetermined lateral distance Wth, then the road condition Cin is determined to be met.

[0061] On the other hand, as shown in Figure 3(B), if the vehicle's path MC crosses the left boundary MBleft, which is the outer boundary MBout of the road range RM, the vehicle's path MC is outside the outer boundary MBout of the road range RM, and therefore the road condition Cin is not met. In particular, in this example, if the left lateral distance Wleft, which is the outer lateral distance Wout, is smaller than the predetermined lateral distance Wth at any point on the vehicle's path MC, the road condition Cin is not met.

[0062] If the vehicle driving support system 10 determines "Yes" in step S230, it proceeds to step S235 and performs a correction process to correct the target deceleration characteristics set in step S215.

[0063] The correction process here is a process that corrects the target deceleration characteristics so that the deceleration of the vehicle 100 due to speed control becomes weaker (smaller). In other words, the correction process here is a process that corrects the target deceleration characteristics so that the deceleration of the vehicle 100 due to the deceleration support process described later becomes weaker (smaller). More specifically, the correction process here is at least one of the following: increasing the target speed Vtgt, decreasing the target deceleration Gdec_tgt, decreasing the target jerk value dGdec_tgt, and delaying the target deceleration support start timing Tstart.

[0064] Next, the vehicle driving support system 10 proceeds to step S245 and determines whether or not the deceleration support implementation condition Cexe is met.

[0065] The deceleration support implementation condition Cexe here is met when the vehicle speed V is greater than the corrected target speed Vtgt if the target speed Vtgt is corrected in step S235, and when the vehicle speed V is greater than the target speed Vtgt set in step S215 if the target speed Vtgt is not corrected in step S235.

[0066] If the vehicle driving support system 10 determines "Yes" in step S245, it proceeds to step S250 and performs deceleration support processing.

[0067] The deceleration support process performed at this time is a process that reduces the driving force applied to the vehicle 100 according to the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, and target deceleration support start timing Tstart, or a process that sets the driving force applied to the vehicle 100 to zero and controls the braking force applied to the vehicle 100.

[0068] Furthermore, the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, and target deceleration support start timing Tstart used in the deceleration support process at this time are the corrected target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, or target deceleration support start timing Tstart if they have been corrected in step S235, and the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, or target deceleration support start timing Tstart set in step S215 if they have been corrected in step S235.

[0069] Then, the vehicle driving support system 10 proceeds to step S295 and terminates the processing of this routine.

[0070] On the other hand, if the vehicle driving support system 10 determines "No" in step S245, it proceeds to step S255, and if deceleration support processing is being performed at that time, it stops the deceleration support processing. Then, the vehicle driving support system 10 proceeds to step S295 and terminates the processing of this routine.

[0071] Furthermore, if the vehicle driving support system 10 determines "No" in step S230, it proceeds to step S240 and performs a correction process to correct the target deceleration characteristics set in step S215.

[0072] The correction process here is a process that corrects the target deceleration characteristics so that the deceleration of the vehicle 100 due to speed control becomes stronger (larger). In other words, the correction process here is a process that corrects the target deceleration characteristics so that the deceleration of the vehicle 100 due to deceleration support processing becomes stronger (larger). More specifically, the correction process here is at least one of the following: a process that reduces the target speed Vtgt, a process that increases the target deceleration Gdec_tgt, a process that increases the target jerk value dGdec_tgt, and a process that advances the target deceleration support start timing Tstart.

[0073] Next, the vehicle driving support system 10 proceeds to step S245 and determines whether or not the deceleration support implementation condition Cexe is met.

[0074] The deceleration support implementation condition Cexe here is met when the vehicle speed V is greater than the corrected target speed Vtgt if the target speed Vtgt is corrected in step S240, and when the vehicle speed V is greater than the target speed Vtgt set in step S215 if the target speed Vtgt is not corrected in step S240.

[0075] If the vehicle driving support system 10 determines "Yes" in step S245, it proceeds to step S250 and performs deceleration support processing.

[0076] Furthermore, the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, and target deceleration support start timing Tstart used in the deceleration support process at this time are the corrected target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, or target deceleration support start timing Tstart if they have been corrected in step S240, and the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, or target deceleration support start timing Tstart set in step S215 if they have been corrected in step S240.

[0077] Then, the vehicle driving support system 10 proceeds to step S295 and terminates the processing of this routine.

[0078] On the other hand, if the vehicle driving support system 10 determines "No" in step S245, it proceeds to step S255, and if deceleration support processing is being performed at that time, it stops the deceleration support processing. Then, the vehicle driving support system 10 proceeds to step S295 and terminates the processing of this routine.

[0079] The above describes the operation of the vehicle driving assistance device 10.

[0080] Thus, when the vehicle driving support device 10 performs speed control, if the vehicle's path MC, which is the path of the vehicle 100 from the vehicle 100 to a predetermined distance (predetermined travel distance Dmove_th) ahead, is within the travel range RM of the curved road CR, the deceleration of the vehicle 100 due to speed control is weaker compared to when the vehicle's path MC is outside the outer boundary MBout of the travel range RM.

[0081] According to this, the degree of deceleration of the vehicle 100 by speed control is determined according to the actual path the vehicle 100 is traveling. Therefore, when the vehicle 100 is traveling on a curved road CR, the deceleration of the vehicle 100 can be controlled to an appropriate level.

[0082] Furthermore, the present invention is not limited to the embodiments described above, and various modifications can be adopted within the scope of the present invention.

[0083] For example, instead of the processing in steps S235, S240, and S245 of the routine shown in Figure 2, processing may be performed to correct at least one of the target speed Vtgt, target deceleration Gdec_tgt, target jerk value dGdec_tgt, and target deceleration support start timing Tstart, as follows.

[0084] In other words, the vehicle driving support device 10 may be configured such that, after processing in step S230, if the distance over which the vehicle's path MC is within the driving range RM (distance within the driving range Din) is greater than or equal to a predetermined distance (predetermined switching distance Dth), the larger the distance within the driving range Din, the greater the degree to which the target deceleration characteristics are reduced so that the deceleration of the vehicle 100 due to speed control is reduced. If the distance within the driving range Din is less than the predetermined switching distance Dth, the smaller the distance within the driving range Din, the greater the degree to which the target deceleration characteristics are reduced so that the deceleration of the vehicle 100 due to speed control is reduced.

[0085] More specifically, the vehicle driving support device 10 may be configured to perform at least one of the following correction processes when the distance Din within the driving range is greater than or equal to a predetermined switching distance Dth: a process that increases the target speed Vtgt more as the distance Din within the driving range increases; a process that decreases the target deceleration Gdec_tgt more as; a process that decreases the target jerk value dGdec_tgt more as; and a process that delays the target deceleration support start timing Tstart more as;

[0086] On the other hand, if the distance within the driving range Din is smaller than a predetermined switching distance Dth, the vehicle driving support device 10 may be configured to perform at least one of the following correction processes: a process that reduces the target speed Vtgt more significantly the smaller the distance within the driving range Din is; a process that increases the target deceleration Gdec_tgt more significantly; a process that increases the target jerk value dGdec_tgt more significantly; and a process that starts the target deceleration support earlier Tstart.

[0087] Thus, when speed control is performed, the vehicle driving support device 10 may be configured to decelerate the vehicle 100 by speed control more strongly the shorter the distance between the point where the vehicle's path MC goes outside the outer boundary MBout of the driving range RM and the vehicle 100 (distance within the driving range Din).

[0088] Furthermore, the vehicle driving support device 10 may be configured such that, if the state of the vehicle 100 is not understeer at the time the process of step S230 is executed, it determines "Yes" in step S230 and proceeds to step S235, and if the state of the vehicle 100 is understeer at the time the process of step S230 is executed, it determines "No" in step S230 and proceeds to step S255.

[0089] Furthermore, the vehicle driving support device 10 may be configured to determine whether the in-road condition Cin in step S230 is met after the yaw rate Y or steering angle θ has started to decrease from its maximum value. Alternatively, the vehicle driving support device 10 may be configured to determine whether the in-road condition Cin in step S230 is met after the so-called steering correction of the vehicle 100 has begun. [Explanation of Symbols]

[0090] 10...Vehicle driving assistance system, 21...Drive system, 22...Braking system, 40...Surrounding information detection system, 50...Road information detection system, 90...ECU, 100...Own vehicle

Claims

1. In a vehicle driving assistance system equipped with a control device that performs speed control to control the vehicle's speed to be less than or equal to the target speed when the vehicle is traveling on a curved road and the vehicle's speed is greater than the target speed, The control device is configured such that, when the speed control is performed, if the vehicle's path, which is the predicted path the vehicle will travel from its current location to a predetermined distance ahead, is within the range of the curved road, the deceleration of the vehicle due to the speed control is weaker compared to when the vehicle's path is outside the outer boundary of the range. Furthermore, the control device is configured to set the predetermined distance to a longer distance the smaller the curvature of the curved road. Vehicle driving assistance system.

2. In the vehicle driving support device according to Claim 1, The control device is configured such that, when the vehicle's path is outside the outer boundary of the track area during speed control, the shorter the distance between the point where the vehicle's path exits the outer boundary of the track area and the vehicle, the stronger the deceleration of the vehicle by the speed control. Vehicle driving assistance system.

3. In the vehicle driving support device according to Claim 1 or Claim 2, The control device is configured to set the target speed when executing the speed control, and to set the target deceleration, which is the target value of the degree of deceleration of the vehicle when the vehicle is decelerated so that the vehicle's travel speed is controlled to be below the target speed, the target deceleration increase rate, which is the target value of the rate at which the degree of deceleration of the vehicle increases, and the target deceleration support start timing, which is the target value of the timing at which the vehicle starts to decelerate, and to execute the speed control according to these target speed, target deceleration, target deceleration increase rate, and target deceleration support start timing. The control device is configured to reduce the deceleration of the vehicle by speed control by performing at least one of the following correction processes when the vehicle's path is within the track range: a correction process to correct the target speed so that it is greater than when the vehicle's path is outside the outer boundary of the track range; a correction process to correct the target deceleration so that it is smaller; a correction process to correct the target deceleration increase rate so that it is smaller; and a correction process to correct the target deceleration support start timing so that the target deceleration support start timing is delayed. Vehicle driving assistance system.

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