JP2008001302A - Vehicle traveling control device and vehicle traveling control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle traveling control device and a vehicle traveling control method capable of alleviating shock when a vehicle passes on a projecting part of a road surface. <P>SOLUTION: The vehicle traveling control device is provided with a projecting part detecting means for detecting the shape of the projecting part on the road surface before the vehicle; a decelerating acceleration setting means for setting acceleration based on the shape of the projecting part; a point setting means for setting a point away from the projecting part by a first distance toward the vehicle as a first point and a point away from the first point by a second distance toward the vehicle as a second point; and a speed control means for reducing the speed of the vehicle by the set acceleration between the second point to the first point and releasing the deceleration of the vehicle when the vehicle reaches the first point. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle travel control device and a vehicle travel control method, and more particularly to travel control during passage of a convex portion on a road surface.

Conventionally, when a vehicle passes through a convex part on the road surface, the throttle valve control reduces the impact when the rear wheel passes through the convex part of the rear wheel by reducing the ground contact load of the rear wheel by making the front wheel nose dive after passing through the convex part. An apparatus is known (for example, Patent Document 1). However, the countermeasures against impact when passing through the convex part of the front wheel are not sufficient.
Speed bumps are sometimes installed at the beginning of road sections in residential areas and parks and at parking lot entrances to encourage deceleration. When passing through such a convex part, if the nose dive is caused by the deceleration and the shock absorber on the front wheel passes through the convex part in a contracted state, the impact in the vertical direction due to overcoming the convex part cannot be absorbed. In addition, when the front wheel rides on the convex part, an impact in the traveling direction is generated in the suspension, but this cannot be absorbed sufficiently by a shock absorber or the like, but can only be absorbed by a rubber bush or mount installed at the suspension link part. There wasn't. As a result, the impact in the traveling direction could not be absorbed sufficiently, and the riding comfort when the convex portion passed was reduced. Further, if the rubber bush or the like is too soft for absorbing the impact, there is a possibility of adversely affecting the steering stability during normal driving.

JP-A-8-319863

  An object of the present invention is to provide a vehicle travel control device and a vehicle travel control method that can alleviate an impact when a vehicle passes through a convex portion of a road surface.

(1) A vehicle travel control device for achieving the above object includes a convex portion detecting means for detecting a shape of a convex portion on a road surface in front of the vehicle, and a deceleration acceleration setting for setting an acceleration based on the shape of the convex portion. Means, a point setting means for setting a point in front of the first distance from the convex portion as a first point, a point setting point in front of the second distance from the first point, and a second point from the second point. Speed control means for decelerating the vehicle with the acceleration between one point and releasing the deceleration of the vehicle when reaching the first point.
According to this vehicle travel control device, by decelerating the vehicle between the second point and the first point, the front part of the vehicle is in a nose dive state lower than the rear part of the vehicle. Moreover, when the first point is reached, the deceleration is canceled, so that the front part of the vehicle is in a nose-up state higher than the rear part of the vehicle, and the convex part can be passed in the nose-up state. In addition, since the acceleration when decelerating from the second point to the first point is set based on the shape of the convex portion, the same acceleration is set regardless of the shape of the convex portion and the acceleration is decelerated. In comparison, an appropriate nose-up state corresponding to the shape of the convex portion can be realized. When the vehicle passes through the convex part, when the front wheel first contacts the convex part by passing the convex part to the front wheel in an appropriate nose-up state according to the shape of the convex part, the slope of the convex part and the front wheel The angle formed by the operating axis of the shock absorbing mechanism is substantially a right angle, so that the shock absorbing mechanism can absorb the impact in the vehicle traveling direction and the vertical direction applied to the front wheels. In addition, since the vehicle is in a nose-up state, for example, the front wheel comes in contact with the convex portion when the shock absorber of the front wheel is fully extended, that is, a sufficient stroke is secured, and the shock absorber of the front wheel is contracted. Compared to the case where the front wheel is in contact with the convex portion in the state, it is easier to absorb the impact. Moreover, since a front wheel contacts a convex part in a nose-up state, it can prevent that the lower end of a vehicle front part contacts a convex part.

(2) In the vehicle travel control device for achieving the above object, the spot setting means may set the first spot and the second spot based on the shape of the convex portion.
According to this vehicle travel control device, the first point and the second point as the sections that decelerate at the acceleration set by the deceleration acceleration setting means are set based on the shape of the convex portion. Compared with the case where those points are set, the appropriate nose-up state according to the shape of the convex portion can be realized.

(3) In the vehicle travel control device for achieving the above object, the point setting means may set a point a third distance before the second point as a third point. The speed control means may decelerate the vehicle at an acceleration smaller than the acceleration between the third point and the second point.
According to this vehicle travel control device, speed control for deceleration is performed in two stages, from the third point to the second point and from the second point to the first point. In order to realize the nose-up state as a natural reaction force of the nose dive state, it is expected that the nose dive state is realized. In order to realize such a nose dive state, speed control is performed between the third point and the second point so as to decelerate at an acceleration smaller than the acceleration between the second point and the first point. Therefore, the speed control for deceleration is not divided into two stages, for example, compared with the case where the vehicle decelerates suddenly between the second point and the first point without decelerating to the second point, the nose dive state and the nose up state This can be realized gently without deteriorating the ride comfort.

(4) The vehicle travel control device for achieving the above object may further include a damping force control means for controlling a damping force of a shock absorber provided on the wheel. When the vehicle travels at least one of the second point to the first point and the first point to the convex portion, the damping force The damping force of the shock absorber on the front wheel of the vehicle may be reduced in the control means.
According to this vehicle travel control device, when the vehicle travels between at least one of the second point and the first point and between the first point and the convex portion, the shock absorber of the front wheel Since the damping force is reduced, the vehicle can be nose dive or nose-up more easily than when the damping force is not changed or increased.

(5) The vehicle travel control device for achieving the above object may further include speed detection means for detecting the speed of the vehicle and passage speed setting means for setting the passage speed of the convex portion. The spot setting means may set the first spot and the second spot based on the speed of the vehicle, the passing speed of the convex portion, and the set acceleration.
According to this vehicle travel control device, based on the vehicle speed, the passing speed of the convex portion, and the set acceleration, it is possible to set the first point and the second point that indicate the section that decelerates with the acceleration.

(6) A vehicle travel control device for achieving the above object includes a convex portion detecting means for detecting a shape of a convex portion on a road surface in front of the vehicle, a first distance and a second distance based on the shape of the convex portion. A point setting means for setting a point before the first distance from the convex portion as the first point, and a point before the second distance from the first point as a second point; and Speed control means for decelerating the vehicle between a second point and the first point and releasing the deceleration when the vehicle reaches the first point.
According to this vehicle travel control device, by decelerating the vehicle between the second point and the first point, the front part of the vehicle is in a nose dive state lower than the rear part of the vehicle. Moreover, when the first point is reached, the deceleration is canceled, so that the front part of the vehicle is in a nose-up state higher than the rear part of the vehicle, and the convex part can be passed in the nose-up state. Since the second point and the first point, which are speed control points for realizing such nose dive state and nose-up state, are set based on the shape of the convex portion, these points are set regardless of the shape of the convex portion. Compared with the case where is set, an appropriate nose-up state according to the shape of the convex portion can be realized. Further, when the vehicle passes through the convex portion, the convex portion when the front wheel first contacts the convex portion by passing the convex portion to the front wheel in a nose-up state appropriately realized according to the shape of the convex portion. The angle formed between the slope of the front wheel and the operating axis of the shock absorbing mechanism for the front wheels is substantially a right angle, so that the impact absorbing mechanism can absorb the impact in the traveling direction and the vertical direction of the vehicle applied to the front wheels. In addition, since the vehicle is in a nose-up state, for example, the front wheel comes in contact with the convex portion when the shock absorber of the front wheel is fully extended, that is, a sufficient stroke is secured, and the shock absorber of the front wheel is contracted. Compared to the case where the front wheel is in contact with the convex portion in the state, it is easier to absorb the impact. Moreover, since a front wheel contacts a convex part in a nose-up state, it can prevent that the lower end of a vehicle front part contacts a convex part.

(7) A vehicle travel control method for achieving the above object includes detecting a shape of a convex portion on a road surface in front of the vehicle, setting an acceleration based on the shape of the convex portion, A point before the distance is set as the first point, a point before the second distance from the first point is set as the second point, and the vehicle is decelerated at the acceleration between the second point and the first point, Releasing the deceleration of the vehicle when the first point is reached.
According to this vehicle travel control method, by decelerating the vehicle between the second point and the first point, the front part of the vehicle is in a nose dive state lower than the rear part of the vehicle. Moreover, when the first point is reached, the deceleration is canceled, so that the front part of the vehicle is in a nose-up state higher than the rear part of the vehicle, and the convex part can be passed in the nose-up state. In addition, since the acceleration when decelerating from the second point to the first point is set based on the shape of the convex portion, the same acceleration is set regardless of the shape of the convex portion and the acceleration is decelerated. In comparison, an appropriate nose-up state corresponding to the shape of the convex portion can be realized. When the vehicle passes through the convex part, by passing the convex part through the front wheel in an appropriate nose-up state according to the shape of the convex part, the slope of the convex part and the front wheel when the front wheel first contacts the convex part The angle formed by the operating axis of the shock absorbing mechanism is substantially a right angle, so that the shock absorbing mechanism can absorb the impact in the vehicle traveling direction and the vertical direction applied to the front wheels. In addition, since the vehicle is in a nose-up state, for example, the front wheel comes in contact with the convex portion when the shock absorber of the front wheel is fully extended, that is, a sufficient stroke is secured, and the shock absorber of the front wheel is contracted. Compared to the case where the front wheel is in contact with the convex portion in the state, it is easier to absorb the impact. Moreover, since a front wheel contacts a convex part in a nose-up state, it can prevent that the lower end of a vehicle front part contacts a convex part.

  The functions of the plurality of means provided in the present invention are realized by hardware resources whose functions are specified by the configuration itself, hardware resources whose functions are specified by a program, or a combination thereof. The functions of the plurality of means are not limited to those realized by hardware resources that are physically independent of each other. Further, the order of each operation of the method described in the claims is not limited to the order of description unless there is a technical impediment, and may be executed in any order, and may be executed simultaneously. Also good.

Embodiments of the present invention will be described below.
(First embodiment)
FIG. 2 is a block diagram showing a configuration of the vehicle travel control device 1 according to the first embodiment of the present invention. The vehicle travel control device 1 is mounted on a vehicle such as an automobile or a motorcycle.
The brake unit 10 controls the brake actuator based on the travel control parameter. The electromagnetic valve of the brake actuator is a hydraulic control valve that controls the hydraulic pressure that drives the piston of the brake actuator. When the piston of the brake actuator moves in accordance with the drive hydraulic pressure controlled by the hydraulic control valve, the brake pad pressed against the brake disc or the brake lining pressed against the brake drum is driven.

  The shock absorber unit 14 is provided on each wheel and includes a spring that absorbs an impact received from the road surface, and a shock absorber that includes a piston portion that attenuates expansion and contraction of the spring and stabilizes the vehicle body. The shock absorber may be a hydraulic type or a gas sealed type containing oil and nitrogen gas. The shock absorber unit 14 has a function of changing the damping force of the shock absorber according to the control of the CPU 50. As a method of changing the damping force, a known method may be applied. When the vehicle is in a nose dive state where the front part of the vehicle temporarily sinks during braking, the front wheel shock absorber is contracted with a small stroke amount, and the rear wheel shock absorber is extended with a large stroke amount. On the other hand, when the vehicle is in a nose-up state, the front wheel shock absorber is extended, and the rear wheel shock absorber is contracted.

  In the present embodiment, the vehicle travel control device 1 shares most of the hardware with the navigation device that guides the recommended route to the destination point and the travel point of the host vehicle. On the other hand, the vehicle travel control device 1 may be configured by hardware independent of the navigation device.

  The hard disk device (HDD) 30 serving as the convex portion detection means stores map data and the like. Map data is data composed of information that digitally represents a map in a graph format, and the shape, width, and the like of convex portions such as speed bumps provided on the road surface to detect the position of the vehicle and promote deceleration It is used for obtaining the shape such as height. In the map data, intersections, turning points, dead ends, and the like are nodes, and roads are defined as links connecting nodes. In addition, the distance, speed limit, number of lanes, width, corner radius, presence / absence of a convex portion such as a speed dump, and the shape of the convex portion are defined as attribute information for each link.

The direction sensor 32 includes a geomagnetic sensor, a left and right wheel speed difference sensor, a vibration gyro, a gas rate gyro, an optical fiber gyro, and the like used for dead reckoning navigation.
The GPS unit 34 receives an orbit data transmitted from three or four satellites used for satellite navigation, and outputs an latitude / longitude data of the current location of the host vehicle 90, an ASIC (Application Specific Integrated Circuit). Etc.

  The vehicle speed sensor 36 is used for detection of the travel speed of the vehicle and dead reckoning for specifying the travel position of the vehicle from the travel distance. The mileage is obtained by integrating the vehicle speed obtained from the number of rotations of the wheel per unit time with time. A Doppler ground speed sensor using radio waves or ultrasonic waves, or a ground speed sensor using light and a spatial filter may be used.

  The camera unit 38 serving as a convex detection means is installed so that the front of the vehicle is within the field of view, images the road surface and signs in front of the vehicle, and the presence or absence of convex parts such as speed bumps provided on the road surface. It is used to detect road speed limits. Note that a radar unit may be provided as the convex portion detection means, and the presence or absence of the convex portion on the front road surface and the shape of the convex portion may be acquired from the output value of the radar unit.

  CPU50 controls each part in the vehicle travel control apparatus 1 by running a control program. The CPU of the navigation device may also serve as the CPU 50 of the vehicle travel control device 1, or the CPU 50 may be used exclusively for the vehicle travel control device 1.

The RAM 52 temporarily stores data and programs processed by the CPU 50. The flash memory 54 is a rewritable nonvolatile memory that stores a control program executed by the CPU 50. The control program may be stored in the HDD 30. The control program and map data can be stored in the HDD 30 or the flash memory 54 by downloading from a predetermined server via a network, reading from a computer-readable storage medium such as a removable memory (not shown), and the like.
The CPU 50 functions as a convex portion detection unit, a deceleration acceleration setting unit, a point setting unit, a speed control unit, and a damping force control unit by executing a vehicle travel control process described later.
The configuration of the vehicle travel control device 1 has been described above.

FIG. 3 is a flowchart showing the flow of the vehicle travel control process according to the present embodiment. The vehicle travel control process is executed when it is detected that a convex portion exists on the front road surface of the vehicle. FIG. 1 is a schematic diagram illustrating an example of a change in posture of the vehicle before and during the passage of the convex portion by executing the vehicle travel control process.
The current position of the host vehicle 90 is input from a distance sensor using a correction using map matching using map data, latitude / longitude data of the current location of the host vehicle 90 input from the GPS unit 34, and the vehicle speed sensor 36. Based on the travel distance and the traveling azimuth input from the azimuth sensor 32, it is detected at predetermined time intervals.

  First, the shape of the convex portion on the front road surface is detected (step S100). Specifically, for example, attribute information of a road on which the host vehicle 90 travels is referred to, and when a convex portion exists ahead of the vehicle 90 by a predetermined distance, the shape of the convex portion is acquired. The presence / absence and shape of the convex portion may be detected by analyzing an image of the front road surface taken by the camera unit 38. The presence / absence and shape of the convex portion may be detected based on the output value of the radar unit.

  In step S102, the acceleration A is set based on the shape of the convex portion. Specifically, a nose-up target amount is set according to the shape of the convex portion 80, and an acceleration A for realizing a nose-up state corresponding to the nose-up target amount is calculated and set. The nose-up target amount is, for example, the stroke amount of the shock absorber. The nose-up target amount is set so that, for example, the larger convex portion is larger than the small convex portion.

  In step S104, the first point and the second point are set based on the shape of the convex portion. Specifically, for example, the distance is first calculated from the current position of the host vehicle 90 and the position of the convex portion acquired from the attribute information of the traveling road in step S100. The distance may be calculated from output data from the camera unit 38 or the radar unit. Then, a first point that is a speed control point for realizing a nose-up state for the nose-up target amount set in step S102, and a second point that is a point for starting speed control for realizing a nose dive state. A point is set (see FIG. 1). Of course, the first point and the second point are set as points between the current position of the host vehicle 90 and the convex portion 80. The first point is a point at which deceleration is canceled in order to bring the vehicle 90 into a nose-up state, and in this embodiment, the first point is a point that is separated from the convex portion 80 by a first distance. The first point is set based on the shape of the convex portion. The second point is a point at which control for decelerating the host vehicle 90 at the acceleration A set in step S102 in order to place the host vehicle 90 in the nose dive state, and the second point is away from the first point. Point. The second point is set based on the shape of the convex portion.

In step S105, a third point is set. The third point is a point where control for decelerating the host vehicle 90 at an acceleration B (for example, 0.2 G) is started in order to make the host vehicle 90 nose dive and nose up without deteriorating the ride comfort. The third distance from the two points. The third point is set according to the vehicle speed of the host vehicle 90 when traveling at a position before the third point. Of course, the third point is also set as a point between the current position of the host vehicle 90 and the convex portion 80.
FIG. 6 is a schematic diagram showing the relationship between the convex portion, the first point, the second point, and the third point, and the speed of the host vehicle 90 between those points.

  In the present embodiment, the release of the deceleration performed at the first point means that the deceleration that has been performed up to the first point is completely cancelled. Note that, at the first point, speed control may be performed such that the vehicle is decelerated at an acceleration smaller than the acceleration A used from the second point to the first point, for example, instead of being completely canceled.

  Thus, in this embodiment, since acceleration A, the 1st point, and the 2nd point are set based on the shape of a convex part, and the speed of the own vehicle 90 is controlled, it is not based on the shape of a convex part. Compared with the case where they are set and the speed is controlled, an appropriate nose-up state corresponding to the shape of the convex portion can be realized.

In step S106, it is determined whether the own vehicle 90 has passed the third point.
In step S108, when it is determined in step S106 that the vehicle has passed the third point, control for decelerating at the acceleration B is started. Specifically, the speed is controlled by the brake unit 10 in accordance with the acceleration B set in the CPU 50. FIG. 1A shows the host vehicle 90 at this time. Since it is not rapid deceleration, the host vehicle 90 does not dive greatly.

In step S110, it is determined whether the vehicle 90 has passed the second point.
In step S112, if it is determined in step S110 that the second point has been passed, control for decelerating at acceleration A is started. Specifically, the speed is controlled by the brake unit 10 in accordance with the acceleration A set in the CPU 50. From the second point to the first point, control is performed to decelerate the own vehicle 90 at an acceleration A greater than the acceleration B from the third point to the second point, so that the own vehicle 90 is in a nose dive state. FIG. 1B shows the host vehicle 90 at this time. At this time, the shock absorber 92 of the front wheel is in a contracted state.

  Further, in the nose dive control in step S112, the shock absorber unit 14 may reduce the damping force of the shock absorber 92 for the front wheels in accordance with the control of the CPU 50. By reducing the damping force of the front wheel shock absorber 92, it becomes easier to nose dive than when the damping force does not change or increases.

In step S114, it is determined whether the vehicle 90 has passed the first point.
In step S116, if it is determined in step S114 that the first point has been passed, deceleration is cancelled. When the deceleration is released, the host vehicle 90 enters a nose-up state. FIG. 1C shows a moment when the vehicle 90 is in a nose-up state and contacts the convex portion 80. At this time, the shock absorber 92 of the front wheel is in an extended state, a sufficient stroke amount is secured, and the vibration in the direction of the arrow 100 is attenuated. Further, since the vehicle is in the nose-up state, the front lower end of the host vehicle 90 does not contact the convex portion 80. As shown in FIG. 5, when the arrow 100 indicating the operating direction of the shock absorber 92 is in a nose-up state so as to be substantially perpendicular to the inclined surface 80 a of the convex portion 80, The shock absorber 92 can simultaneously absorb the impact in the traveling direction (broken arrow 100b) due to the contact and the impact in the vertical direction (broken arrow 100a) due to riding on the convex portion 80.

  In step S116, the shock absorber unit 14 may reduce the damping force of the shock absorber 92 for the front wheels in accordance with the control of the CPU 50. By reducing the damping force of the front wheel shock absorber 92, it becomes easier to nose up than when the damping force does not change or increases. The control for reducing the damping force of the shock absorber 92 for the front wheels in steps S112 and S116 may be performed by both or may be performed by either.

  FIG. 1D shows a state where the front wheel passes through the convex portion 80. The impact in the vertical direction (arrow 102) due to the front wheel riding on the convex portion 80 is absorbed. Compared to the nose dive state, there is a surplus in the stroke amount, so it is easy to absorb the impact.

  Thus, in this embodiment, speed control for deceleration is performed in two stages, from the third point to the second point and from the second point to the first point. In order to realize the nose-up state as a natural reaction force of the nose dive state, the nose dive state is expected to be realized. In order to realize such a nose dive state, speed control is performed between the third point and the second point so as to decelerate at a lower acceleration than that when decelerating between the second point and the first point. Done. Therefore, the speed control for deceleration is not divided into two stages, for example, compared with the case where the vehicle is decelerated suddenly between the second point and the first point without decelerating to the second point, in this embodiment, the nose dive state and The nose-up state can be achieved gradually without deteriorating the ride comfort.

  The acceleration A, the first point, and the second point are in a nose dive state when the rear wheel passes the convex part 80 by the natural reaction force after the front wheel passes the convex part 80 in the nose-up state. May be set. That is, for example, if the acceleration A, the first point, and the second point that greatly increase the nose are set for the small convex part, the rear wheel may pass through the convex part 80 before entering the nose dive state. Therefore, the acceleration A, the first point, and the second point are set in consideration of the timing at which the rear wheel passes the convex portion 80 and the posture of the host vehicle 90.

  FIG. 4 shows the host vehicle 90 after the front wheels have passed the convex portion 80 as shown in FIG. When the speed of the host vehicle 90 is controlled by the acceleration and speed control points set in steps S102 and S104, when the front wheel passes through the convex portion 80 in the nose-up state, the host vehicle 90 is noseed again by the natural reaction force. Dive state. At this time, the rear wheel shock absorber 94 is in the extended state as shown in FIG. 4, so that there is a sufficient amount of stroke, and the shock in the vertical direction (arrow 104) due to riding on the convex portion 80 can be absorbed. . The acceleration A, the first point, and the second point set for the front wheel to pass through the convex portion 80 in the nose-up state are synchronized with the vehicle 90 again in the nose-dive state due to the natural reaction force in the nose-up state. Since the rear wheel is set so as to pass through the convex portion 80, not only can the impact when the front wheel passes through the convex portion 80 be absorbed, but also the impact when the rear wheel passes through the convex portion 80 is absorbed. can do.

(Second Embodiment)
FIG. 7 shows a flowchart of the vehicle travel control process according to the second embodiment of the present invention. The configuration of the vehicle travel control device 1 of the second embodiment is substantially the same as the vehicle travel control device 1 of the first embodiment. In the flowchart shown in FIG. 7, the same step numbers are assigned to steps that perform the same processing as in the flowchart of FIG. 3. Further, by executing the vehicle travel control process shown in FIG. 7, the CPU 50 also functions as a speed detection means and a passing speed setting means. Further, the vehicle speed sensor 36 corresponds to the speed detection means described in the claims.

The second embodiment differs from the first embodiment in that the first point and the second point are set based on the shape of the convex portion in the first embodiment, whereas the current vehicle in the second embodiment. This is a point set based on the speed of the projection, the passing speed of the convex portion, and the acceleration (acceleration A) when decelerating between the second point and the first point.
In step S100 and step S102, the same processing as in the flowchart of FIG. 3 is performed.
In step S204, the speed of the vehicle is detected. Specifically, the current speed of the host vehicle 90 is acquired from the vehicle speed sensor 36.

In step S206, the passing speed of the convex portion is set. The passing speed of the convex portion may be set according to the shape of the convex portion, or may be set according to a predetermined speed such as 15 km / h in a parking lot, for example.
In step S208, the first point and the second point are set based on the speed of the vehicle, the passing speed of the convex portion, and the acceleration A.
In steps S110, S112, S114, and S116, the same processing as in the flowchart of FIG. 3 is performed.

In step S208, a third point that is a third distance away from the second point is further set, and between the third point and the second point, an acceleration B (for example, 0.2 G) smaller than the acceleration A is set. The car 90 may be decelerated.
Further, when at least one of steps S112 and S116 is executed, the shock absorber unit 14 may reduce the damping force of the shock absorber 92 for the front wheels in accordance with the control of the CPU 50.

(Third embodiment)
FIG. 8 shows a flowchart of the vehicle travel control process according to the third embodiment of the present invention. The configuration of the vehicle travel control device 1 of the third embodiment is substantially the same as the vehicle travel control device 1 of the first embodiment. Further, in the flowchart shown in FIG. 8, steps that perform the same processing as in the flowchart of FIG. 3 are given the same step numbers.

  The third embodiment is different from the first embodiment in that the speed control point (first point and second point) and acceleration (acceleration A) are set based on the shape of the convex portion in the first embodiment. On the other hand, in the second embodiment, what is set according to the shape of the convex portion is a point that is a speed control point (first point and second point).

In steps S100, S104, S110, S114, and S116, the same processing as the flowchart of FIG. 3 is performed.
In step S312, control is performed to reduce the speed of the host vehicle 90 at a constant acceleration (eg, 0.3 G) between the second point and the first point set in step S104.
When at least one of steps S312 and S116 is executed, the shock absorber unit 14 may reduce the damping force of the shock absorber 92 for the front wheels in accordance with the control of the CPU 50.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof. For example, the present invention is also applicable when controlling an impact absorbing mechanism other than the shock absorber described in the above embodiment. The deceleration may be realized as an engine brake by changing the gear ratio of the automatic vehicle, or may be realized by controlling the fuel injection amount and the throttle opening in the internal combustion engine. Moreover, you may implement | achieve by changing the rotation speed of the motor of a regenerative brake. The position and size of the convex portion may be stored in the map data by recording an acceleration sensor installed in the vehicle.

The schematic diagram which shows the vehicle travel control which concerns on 1st Embodiment of this invention. The block diagram which shows the structure of the vehicle travel control apparatus which concerns on 1st Embodiment of this invention. The flowchart which shows the vehicle travel control process which concerns on 1st Embodiment of this invention. The schematic diagram which shows the vehicle travel control which concerns on 1st Embodiment of this invention. The schematic diagram which concerns on 1st Embodiment of this invention. The schematic diagram which concerns on 1st Embodiment of this invention. The flowchart which shows the vehicle travel control process which concerns on 2nd Embodiment of this invention. The flowchart which shows the vehicle travel control process which concerns on 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1: Vehicle travel control apparatus, 10: Brake unit, 14: Shock absorber unit, 30: HDD (convex part detection means), 32: Direction sensor, 34: GPS unit, 36: Vehicle speed sensor, 38: Camera unit (convex part) Detection means), 50: CPU (convex detection means, deceleration acceleration setting means, point setting means, speed control means, damping force control means, speed detection means, passage speed setting means), 52: RAM, 54: flash memory, 80: convex part, 90: own vehicle

Claims (7)

Convexity detecting means for detecting the shape of the convexity on the front road surface of the vehicle;
Deceleration acceleration setting means for setting acceleration based on the shape of the convex part;
A point setting means for setting a point before the first distance from the convex portion as a first point and a point before the second distance from the first point as a second point;
Speed control means for decelerating the vehicle with the acceleration between the second point and the first point, and releasing the deceleration of the vehicle when reaching the first point;
A vehicle travel control device comprising: The point setting means sets the first point and the second point based on the shape of the convex portion,
The vehicle travel control device according to claim 1. The point setting means sets a point a third distance before the second point as a third point,
The speed control means decelerates the vehicle at an acceleration smaller than the acceleration between the third point and the second point.
The vehicle travel control device according to claim 1 or 2. A damping force control means for controlling the damping force of a shock absorber provided on the wheel;
When the vehicle travels at least one of the second point to the first point and the first point to the convex portion, the damping force Reducing the damping force of the shock absorber on the front wheel of the vehicle to the control means;
The vehicle travel control apparatus according to any one of claims 1 to 3. Speed detecting means for detecting the speed of the vehicle;
Passing speed setting means for setting the passing speed of the convex portion, and
The point setting means sets the first point and the second point based on the speed of the vehicle, the passing speed of the convex portion, and the set acceleration.
The vehicle travel control device according to claim 1. Convexity detecting means for detecting the shape of the convexity on the front road surface of the vehicle;
A first distance and a second distance are set based on the shape of the convex portion, the point before the first distance from the convex portion is the first point, and the second distance is short before the first point. A point setting means for setting the point as the second point;
Speed control means for decelerating the vehicle between the second point and the first point, and releasing the deceleration when reaching the first point;
A vehicle travel control device comprising: Detect the shape of the convex part on the front road surface of the vehicle,
Set the acceleration based on the shape of the convex part,
A point before the first distance from the convex portion is set as the first point, a point before the second distance from the first point is set as the second point,
The vehicle is decelerated at the acceleration between the second point and the first point, and when the first point is reached, the vehicle is decelerated.
Including that.

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