JPH10338055A - Vehicular follow-up running control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a vehicle from approaching other vehicle ahead when the vehicle or another vehicle just in front of it on the same lane is changing the lane or after it has changed the lane. SOLUTION: A vehicle 1 detects the actual distances to vehicles 2, 3 ahead. When the vehicle 1 is changing lanes from 4 to 5, the desired acceleration or deceleration for intervehicular distance control regarding the vehicle 2 ahead which travels on the initial lane 4 is compared with the desired acceleration or deceleration for intervehicular distance control regarding the vehicle 3 ahead which is traveling on the lane 5 to which the vehicle 1 has shifted, and the smaller desired acceleration or deceleration is selected to control the vehicle 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle cruising control system.

[0002]

2. Description of the Related Art Conventionally, as such a vehicle following travel control device, for example, Japanese Patent Application Laid-Open Nos.
There is one described in JP-A-6-135259.

[0003] The following control system for a vehicle described in Japanese Patent Application Laid-Open No. Hei 5-345537 uses image processing so that a vehicle ahead of the vehicle in the traveling lane even on a curved road can be reliably followed. When the vehicle immediately before the same lane starts changing lanes, the own vehicle stops running following the immediately preceding vehicle, and the own vehicle maintains the vehicle speed at this time.

In the following control system for a vehicle described in Japanese Patent Application Laid-Open No. Hei 6-135259, the actual inter-vehicle distance measured by the distance sensor includes noise, and the relative distance calculated by differentiating the actual inter-vehicle distance is calculated. When controlling using speed, it is usually necessary to perform some sort of filter processing. As a result, a delay occurs between the time when the inter-vehicle distance sensor captures the vehicle immediately before the same lane as the own vehicle and the time when the relative speed is calculated and control is started. If the later traveling lane speed is lower than the traveling lane speed before the change, the slower traveling lane speed is stored in advance in order to prevent the own vehicle from approaching too close to the immediately preceding vehicle. After the vehicle changes to the slower traveling lane, control is performed at that vehicle speed.

[0005]

However, in the vehicle following travel control device described in Japanese Patent Application Laid-Open No. Hei 5-345537, the vehicle preceding the own vehicle starts changing lanes during the following travel control. Sometimes, when the host vehicle stops following the preceding vehicle, if the preceding vehicle decelerates while changing lanes, the host vehicle approaches the preceding vehicle too much,
There is a possibility that the occupant of the host vehicle will feel uncomfortable. In addition, it is very difficult to recognize a plurality of driving lanes and a plurality of vehicles by image processing while the own vehicle or the preceding vehicle changes the driving lane due to calculation time and complexity of the algorithm.

In the following control system for a vehicle described in the above-mentioned Japanese Patent Application Laid-Open No. 6-135259, after the change of the traveling lane is completed, the control is performed with the slower traveling lane speed stored in advance in the traveling lane. Is started, if the speed of the own vehicle is higher than the speed of the vehicle immediately before the own vehicle after the change of the driving lane (the speed stored in advance), the moving lane of the own vehicle is changed during the changing of the driving lane. There is a possibility that an occupant of the own vehicle may feel uncomfortable because the vehicle is too close to the vehicle immediately before the own vehicle traveling on the vehicle.

[0007] If the slower lane speed stored in advance does not match the speed of the vehicle immediately before the host vehicle after the host vehicle has changed, the host vehicle after the host vehicle has changed the host vehicle lane. Is delayed until the speed of the vehicle immediately before is calculated as the sum of the vehicle speed of the host vehicle and their relative speeds. As a result, if the traveling lane speed stored in advance is higher than the speed of the own vehicle, the own vehicle changes the traveling lane and then approaches the vehicle traveling in the traveling lane, and the occupant feels uncomfortable. May be given. Further, when the traveling lane speed stored in advance is low, the own vehicle changes the traveling lane, and then is separated from the vehicle immediately before traveling in the traveling lane.

According to the first to eighth aspects of the invention, there is a possibility that the vehicle or the vehicle immediately before the same lane as the vehicle may approach the other preceding vehicle during or after the lane change. It is to solve the problem.

[0009]

According to a first aspect of the present invention, there is provided a vehicle follow-up cruise control device which measures actual inter-vehicle distances between a host vehicle and a plurality of preceding vehicles, and measures the actual distance between the host vehicle and a plurality of preceding vehicles. The target inter-vehicle distance is set, and the target acceleration / deceleration is calculated from the inter-vehicle distance deviation between the actual inter-vehicle distance and the corresponding target inter-vehicle distance.The engine output and the engine output of the own vehicle are calculated based on the target acceleration / deceleration. In a vehicle following travel control device for controlling a braking force,
The vehicle is controlled by selecting the minimum one of the target accelerations / decelerations.

According to a second aspect of the present invention, there is provided a vehicle follow-up cruise control device for measuring actual inter-vehicle distances between a host vehicle and a plurality of preceding vehicles, and a self-vehicle and a plurality of preceding vehicles. Target inter-vehicle distance setting means for setting respective target inter-vehicle distances; target acceleration / deceleration calculation means for calculating target acceleration / deceleration from the inter-vehicle distance deviation between the actual inter-vehicle distance and the corresponding target inter-vehicle distance; In a vehicle cruising control device comprising an engine output and braking force control means for controlling an engine output and a braking force of the vehicle based on the acceleration / deceleration, selecting a minimum one of the target acceleration / deceleration. The present invention is characterized in that target acceleration / deceleration selecting means for controlling the own vehicle is provided.

According to a third aspect of the present invention, there is provided a vehicle follow-up traveling control device including a vehicle traveling lane and a lane change determining means for determining a traveling lane and a lane change of the vehicle, and the target acceleration / deceleration selecting means includes: When the lane change of the own vehicle is determined by the own vehicle traveling lane and the lane change determining means, the minimum one of the target accelerations / decelerations is selected to control the own vehicle. It is.

According to a fourth aspect of the present invention, there is provided a vehicle follow-up cruise control device comprising a preceding vehicle traveling lane and a lane change determining means for determining a traveling lane and a lane change of the plurality of preceding vehicles, respectively. The selecting means, when judging at least one lane change of the plurality of preceding vehicles by the preceding vehicle traveling lane and the lane change judging means, selects the smallest one of the target acceleration / deceleration to set the own vehicle. It is characterized in that it is controlled.

According to a fifth aspect of the present invention, there is provided a vehicle follow-up cruise control device, comprising: acceleration / deceleration estimated value calculating means for calculating an estimated acceleration / deceleration estimated value of the own vehicle; and the target which needs the estimated acceleration / deceleration estimated value. Braking force control starting means for judging start of braking force control by the engine output and braking force control means when the required target acceleration / deceleration is negative and the required target acceleration / deceleration is negative. It is a feature.

According to a sixth aspect of the present invention, in the vehicle follow-up traveling control apparatus, the target acceleration / deceleration calculating means calculates the target acceleration / deceleration for the inter-vehicle control of the own vehicle by using a PID using the inter-vehicle distance deviation. It is characterized by being calculated by control.

According to a seventh aspect of the present invention, there is provided the vehicle following traveling control apparatus, wherein the target acceleration / deceleration calculating means calculates a sum of the target acceleration / deceleration, a road surface gradient, and a traveling resistance used for controlling the host vehicle. The required target acceleration / deceleration is calculated.

According to another aspect of the present invention, the acceleration / deceleration estimated value calculating means considers a road surface gradient and a running resistance when obtaining the acceleration / deceleration estimated value. It is a feature.

[0017]

According to the vehicle running control apparatus of the first aspect, the own vehicle is controlled by selecting the minimum target acceleration / deceleration. By controlling the own vehicle using the minimum target acceleration / deceleration in this way, there is no possibility that the own vehicle or the preceding vehicle is too close to another preceding vehicle during or after the lane change.

According to the second aspect of the invention, the target acceleration / deceleration selecting means selects the minimum one of the target acceleration / decelerations and controls the own vehicle. By controlling the own vehicle using the minimum target acceleration / deceleration in this way, there is no possibility that the own vehicle or the preceding vehicle is too close to another preceding vehicle during or after the lane change.

According to the third aspect of the present invention, the target acceleration / deceleration selecting means determines the lane change of the own vehicle by the own vehicle traveling lane and the lane change determining means. Control the own vehicle by selecting the smallest one. As described above, when the lane change of the own vehicle is determined, the smallest one of the target accelerations / decelerations is selected. Therefore, the possibility that the own vehicle is too close to another preceding vehicle during or after the lane change is more effectively reduced. Can be avoided.

According to the fourth aspect of the invention, the target acceleration / deceleration selecting means determines that at least one of a plurality of preceding vehicles has been changed by the preceding vehicle running lane and the lane change determining means. And controlling the own vehicle by selecting the smallest one of the target accelerations / decelerations. As described above, when at least one of the plurality of preceding vehicles is determined to change lanes, the smallest target acceleration / deceleration is selected, so that at least one of the plurality of preceding vehicles changes during or after the lane change. Can be more effectively avoided from approaching another preceding vehicle too much.

According to the fifth aspect of the present invention, when the estimated acceleration / deceleration value is larger than the required target acceleration / deceleration and the required target acceleration / deceleration is negative, the braking force is reduced. The control start means determines the start of braking force control by the engine output and braking force control means. By making such a determination, it is possible to appropriately determine the start of the control of the braking force.

According to the sixth aspect of the present invention, the target acceleration / deceleration calculation means calculates the target acceleration / deceleration for the inter-vehicle control of the own vehicle by PID control using the inter-vehicle distance deviation. Thereby, the target acceleration / deceleration for the inter-vehicle control of the own vehicle can be preferably calculated.

According to the vehicle follow-up cruise control device, the target acceleration / deceleration calculating means calculates the required target acceleration / deceleration as the sum of the target acceleration / deceleration, the road surface gradient and the running resistance used for controlling the own vehicle. Calculate the speed. Thereby, the required target acceleration / deceleration can be made more appropriate for the actual running of the vehicle.

According to the vehicle running control apparatus of the eighth aspect, the acceleration / deceleration estimated value calculating means considers the road surface gradient and the running resistance when obtaining the acceleration / deceleration estimated value. Thereby, the acceleration / deceleration estimated value can be made closer to the actual acceleration / deceleration.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the operation of a vehicle follow-up running control device according to the present invention will be described. FIG. 1 is a diagram for explaining a case in which the own vehicle changes the traveling lane during control of the vehicle following traveling control device according to the present invention. In this case, the own vehicle 1 detects the actual inter-vehicle distances with the preceding vehicles 2 and 3, respectively. Traveling lane 4 to traveling lane 5 of own vehicle 1
During the lane change, the target acceleration / deceleration for the inter-vehicle control on the preceding vehicle 2 traveling on the original traveling lane 4 and the target for the inter-vehicle control on the preceding vehicle 3 traveling on the traveling lane 5 after the lane change. Since the host vehicle 1 is controlled by comparing the acceleration / deceleration and the smaller target acceleration / deceleration, the preceding vehicle 3 traveling in the traveling lane 5 after the lane change is lower in speed than the preceding vehicle 2 or becomes If it is close, a target acceleration / deceleration for inter-vehicle control of the traveling lane 5 after the lane change with respect to the preceding vehicle 3 is selected, so that the own vehicle 1 is decelerated to travel on the traveling lane 5 after the lane change. 3 is properly maintained.

When the preceding vehicle 3 traveling on the traveling lane 5 after the lane change is higher in speed than the preceding vehicle 2 or farther from the host vehicle 1, the inter-vehicle control for the preceding vehicle 2 traveling on the traveling lane 4 before the lane change is performed. Therefore, unnecessary deceleration is not performed on the own vehicle 1 and the inter-vehicle distance with the preceding vehicle 2 traveling on the traveling lane 4 before the lane change is appropriately maintained.

FIG. 2 is a diagram for explaining a case in which the vehicle preceding the host vehicle changes the lane of travel during the control of the vehicle following travel control device according to the present invention. Also in this case, the own vehicle 6 detects the actual inter-vehicle distances with the preceding vehicles 7 and 8, respectively. During the lane change of the preceding vehicle 7 from the traveling lane 9 to the traveling lane 10, the target acceleration / deceleration for the inter-vehicle control with respect to the original preceding vehicle 7 and the inter-vehicle distance with respect to the preceding vehicle 8 traveling ahead of the original preceding vehicle 7 Since the host vehicle 6 is controlled by comparing the target acceleration / deceleration for control with the smaller target acceleration / deceleration, when the preceding vehicle 7 changing lanes decelerates, the preceding vehicle 7 changing lanes changes. Since the target acceleration / deceleration for the inter-vehicle control for the vehicle 7 is selected, the host vehicle 6 is decelerated, and the inter-vehicle distance with the preceding vehicle 7 whose lane is being changed is appropriately maintained.

If the speed of the preceding vehicle 8 traveling ahead of the original preceding vehicle 7 is very low, the target acceleration / deceleration for the inter-vehicle control of the preceding vehicle 8 traveling ahead of the original preceding vehicle 7 is also considered. Is selected, the host vehicle 6 is decelerated, and after the preceding vehicle 8 changes lanes from the driving lane 9 to the driving lane 10, the occupant of the host vehicle 6 feels strange because the host vehicle 1 approaches the preceding vehicle 8 too much. The possibility of giving can be avoided.

After the original preceding vehicle 7 has changed lanes from the traveling lane 9 to the traveling lane 10, the target acceleration / deceleration for the headway control for the preceding vehicle 8 traveling ahead of the original preceding vehicle 7 is calculated in advance. Since the host vehicle 1 is controlled using the control signal, the control delay until the relative speed between the host vehicle 6 and the preceding vehicle 8 is calculated does not occur. It is possible to prevent the host vehicle 6 from being separated from or too close to the preceding vehicle 8 after changing lanes to the driving lane 10 from.

Although FIGS. 1 and 2 illustrate the case where there are two traveling lanes, the same applies to other traveling lanes. An embodiment of a vehicle follow-up running control device according to the present invention will be described in detail with reference to the drawings. In the drawings, the same members are denoted by the same reference numerals.

Next, an embodiment of a vehicle follow-up running control device according to the present invention will be described in detail with reference to the drawings. In the drawings, the same members are denoted by the same reference numerals. FIG.
1 is a system diagram showing a configuration of a vehicle having a vehicle follow-up running control device according to the present invention. In the present embodiment, the drive system of the vehicle 11 is FR (front engine rear drive). In FIG. 3, a vehicle 11 includes front wheels 12R, 12R.
L, rear wheels 13R, 13L, engine 14, automatic transmission 1
5, a following travel control device 16, a braking pressure control device 17, a differential gear 18, and a brake pedal 19 are provided.

The inter-vehicle distance detecting device 20 detects the distance between the vehicle 11 and the preceding vehicle. The throttle opening control device 21 controls the throttle opening. The wheel speed detectors 22R and 22L detect the wheel speeds of the rear wheels 13R and 13L, respectively. Wheel braking device 23R, 23L
Brakes the rear wheels 13R and 13L, respectively. The brake pedal switch 24 detects that the driver has depressed the brake pedal 19. The image processing device 25 includes, for example, a CCD as described in JP-A-5-345537.
(charge coupled device) The image captured by the camera 26 is processed.

FIG. 4 is a block diagram for explaining the control of the vehicle follow-up running control device according to the present invention. 4, target inter-vehicle distance setting device 27 sets a target inter-vehicle distance between vehicle 11 (FIG. 3) and the preceding vehicle. The multiple target acceleration / deceleration calculation device 28 is a target inter-vehicle distance setting device 2
A plurality of target accelerations / decelerations are calculated from the target inter-vehicle distance set by 7 and the corresponding actual inter-vehicle distance detected by the scanning inter-vehicle distance detection device 20. The target acceleration / deceleration calculation device 29 calculates the target acceleration / deceleration of the vehicle 11 (FIG. 3). The preceding vehicle traveling lane determining device 30 and the own vehicle traveling lane determining device 31 correspond to the image processing device 25 and the CCD camera 26 in FIG.

The operation of this embodiment will be described. FIG. 5 is a flowchart illustrating the operation of the vehicle follow-up running control device according to the present invention. This routine is executed by the following travel control device 16.
(FIG. 3) is repeatedly executed at predetermined intervals.
In the present routine, first, in step 111, the multiple target acceleration / deceleration calculation device 28 (FIG. 4) determines the actual vehicle-to-vehicle distance with one or more vehicles obtained by the scan-type vehicle distance detection device 20 (FIGS. 3 and 4). A target acceleration / deceleration G ^* used for vehicle control is calculated based on the distance.

Next, at step 112, the running resistance, a constant vehicle weight, and the torque ratio of the torque converter of the automatic transmission 15 (FIG. 3) obtained from the target acceleration / deceleration G ^* calculated at step 111 using a map. The target throttle opening θ ^* is calculated in consideration of the gear ratio of the differential gear 18 (FIG. 3) and the engine map.

Next, in step 113, a command is sent to a throttle control motor (not shown) so that the actual throttle opening θ matches the target throttle opening θ ^* .

Next, at step 114 as the acceleration / deceleration estimated value calculating means, the engine map, the torque ratio of the torque converter (not shown), the gear ratio of the differential gear 13 (FIG. 1), the response delay of the engine brake torque, the constant The estimated acceleration / deceleration value g is calculated in consideration of the vehicle weight of the vehicle and the vehicle resistance obtained from the map.

Next, in step 115 as the brake fluid pressure control starting means, the target acceleration / deceleration g ^* required for determining the start of the brake fluid pressure control is larger than the acceleration / deceleration estimated value g calculated in step 114. Further, it is determined whether or not the target acceleration / deceleration g ^* is negative. If the required target acceleration / deceleration g ^* is larger than the estimated acceleration / deceleration g calculated in step 114 and the target acceleration / deceleration g ^* is negative, the process proceeds to the next step 116. Otherwise, steps 116 and 117 described later are skipped, and the routine ends.

Next, at step 116, the braking hydraulic pressure control device 19 (FIGS. 3 and 4) calculates the target braking pressure p from the target acceleration / deceleration g _G ^* described later and the estimated acceleration / deceleration g calculated at step 115. Calculate ^* . Thereafter, in step 117, the actual braking pressure is set to the target braking pressure p ^*.
The command value is output to the brake fluid pressure control device 19 (FIGS. 3 and 4) so as to coincide with the above, and this routine ends.

Step 113 and step 117
Constitutes engine output and brake fluid pressure control means.

FIG. 6 is a flowchart of the control program executed in step 111 of the flowchart of FIG. In this routine, first, the image taken by the preceding vehicle traveling lane determining device 30 (FIG. 4) and the own vehicle traveling lane determining device 31 (FIG. 4) (that is, the image captured by the CCD camera (FIG. 3) is processed by the image processing device 25 (FIG. 4)). It is determined whether or not the vehicle 1 (FIG. 3) or the vehicle preceding the vehicle 1 is changing the traveling lane by performing the image processing 3).

If the driving lane is not being changed, there is only one vehicle to be subjected to the inter-vehicle control, and in step 102, the vehicle 1 (FIG. 3) is compared with the preceding vehicle traveling in the same driving lane as the driving lane. An inter-vehicle distance d1 is calculated, and a target acceleration / deceleration G1 for performing inter-vehicle control is calculated based on the inter-vehicle distance d1. Specifically, in steps 201 to 205 in FIG. 7, G = 1 is calculated with i = 1. Then, in step 103 as a target acceleration / deceleration calculation means, the target acceleration / deceleration G ^* for controlling the vehicle is set to G1, and this routine ends.

On the other hand, when the driving lane is being changed, there may be a plurality of preceding vehicles to be subjected to the inter-vehicle control.
(1), 104- (2),. . . , 104- (n), calculates the inter-vehicle distances d1 to dn with the first to n-th vehicles among the vehicles preceding the vehicle 1 (FIG. 3), and performs the inter-vehicle control based on the calculated distances. Target acceleration / deceleration G1
To Gn are calculated. Specifically, in steps 201 to 205 in FIG. 7, the target inter-vehicle distance d ^* i is set for the i-th (i = 1 to n) vehicle, the actual inter-vehicle distance di is measured, and the i-th vehicle is measured. Target acceleration / deceleration Gi for the vehicle
Is calculated. This calculation is repeated from i = 1 to n to calculate G1 to Gn. After that, in step 105 as the target acceleration / deceleration calculation means, the minimum target acceleration / deceleration G ^* for performing vehicle control is selected from the target acceleration / decelerations G1 to Gn, and this routine ends.

FIG. 7 shows steps 102, 104- (1), 104- (2),. . . , 1
It is a flowchart of the control program executed in 04- (n), and shows the target inter-vehicle distance and i
From the actual inter-vehicle distance to the i-th vehicle, i of vehicle 1 (FIG. 3)
The target acceleration / deceleration Gi for performing the inter-vehicle control on the first preceding vehicle is calculated.

In this routine, first, in step 201, the vehicle speed v of the vehicle 11 (FIG. 3) is measured based on the wheel speed detected by the wheel speed detecting devices 22R and 22L (FIG. 3).

Next, in step 202 as the actual inter-vehicle distance measuring means, the scanning inter-vehicle distance detecting device 20 is used.
The inter-vehicle distance di between the vehicle 11 (FIGS. 3 and 4) and the ith preceding vehicle is measured by (FIGS. 3 and 4).

Next, in step 203 as target inter-vehicle distance setting means, the target inter-vehicle distance setting device 27 (FIG. 4) determines the time (inter-vehicle time) until the vehicle 11 (FIG. 3) reaches the current position of the preceding vehicle. ) Calculate the target inter-vehicle distance di ^* such that T ₀ is constant. In the present embodiment, the target inter-vehicle distance di ^* is

[Number 1] di ^* = T be calculated on the basis of the ₀ v + d0. Here, the initial value of di ^* is set to d0 so that the vehicle 1 (FIG. 3) does not suddenly accelerate or decelerate when the preceding vehicle disappears or is interrupted.
The value is corrected to be i.

Next, in step 204, the plural target acceleration / deceleration calculating device 28 (FIG. 4) calculates an inter-vehicle distance deviation Δdi between the actual inter-vehicle distance di and the target inter-vehicle distance di ^* . That is, the inter-vehicle distance deviation Δdi is

## EQU2 ## It is calculated by Δdi = di−di ^* .

Next, in step 205 as a target acceleration / deceleration calculating means, a plurality of target acceleration / deceleration calculating devices 28
(FIG. 4) shows the target acceleration / deceleration Gi,

Equation 3] is calculated by _{Gi = (k P + k D} s + k I / s) Δdi, the routine ends. In Equation 3, the first, second, and third terms on the right side are PID (proport
ional plus integral plus derivative) control, in which k _P , k _I, and k _D are a proportional gain, an integral gain, and a differential gain, respectively. Let s be the Laplace operator.

FIG. 8 is a flowchart of a control program executed in step 112 of the flowchart of FIG. In this routine, from the required target acceleration / deceleration g ^* ,
Running resistance obtained using the map, constant vehicle weight,
The target throttle opening is calculated in consideration of the torque ratio of the torque converter (not shown), the gear ratio of the differential gear 13 (FIG. 1), and the engine map.

[0051] First, in step 501, the target acceleration G ^*, g sensor vehicle obtained by the road gradient g _g and maps obtained by (not shown) 11
By adding the running resistance g _r (FIG. 3), to calculate the actual target acceleration g ^* required. Therefore, the required target acceleration / deceleration g ^* is

[Number 4] g ^* = a _{^{G * + g g + g r}} .

Next, in step 302, the throttle opening control device 5 (FIGS. 1 and 2) multiplies the required target acceleration / deceleration g ^* by the vehicle weight m and the wheel radius r to obtain the target wheel torque τ ^* _whl. Is calculated. Therefore, the target wheel torque τ ^* _whl is

## _EQU5 ## τ ^* _whl = rmg ^* .

Next, in step 303, the engine speed N _eng is read, and then, in step 304, the output speed (turbine speed) N _t and the input speed (engine speed) of the torque converter (not shown). The speed ratio e of the torque converter is calculated from _Neng . Therefore, the speed ratio e is

The [number 6] e = N _t / N _eng.

Next, at step 305, the torque ratio ηt is calculated from the speed ratio e of the torque converter. Therefore, the torque ratio ηt is

Ηt = f _t (e) This will be described later in detail with reference to FIG.

[0055] Then, in step 306, reads the gear ratio Itag the differential gear 18 (FIG. 3), then, in step 307, the target wheel torque tau ^* _{wh l,} the target engine torque tau a torque ratio ηt and gear ratio Itag ^* Calculate _eng . Therefore, the target engine torque τ ^* _eng is

Τ ^* _eng = τ ^* _whl / _ηt · _ηg

[0056] Then, in step 308, and calculates a target throttle opening theta ^* from the target engine torque tau ^* _eng and the engine speed N _eng, the routine ends. Therefore, the target throttle opening θ ^* is

_Equation 9: θ ^* = f _eng (τ ^* _eng , N _eng ) This will be described later in detail with reference to FIG.

FIG. 9 is a flowchart of the control program executed in step 113 of the flowchart of FIG. In this routine, a command is sent to a throttle control motor (not shown) so that the actual throttle opening θ matches the target throttle opening θ ^* .

First, in step 401, the throttle opening control device 15 (FIGS. 3 and 4) reads the actual throttle opening θ. Thereafter, in step 402, the target throttle opening θ ^* calculated in step 308
And a throttle opening deviation Δθ between the actual throttle opening θ calculated in step 401 and

## EQU10 ## It is calculated by Δθ = θ ^* −θ.

Next, at step 403, the throttle opening control device 5 (FIGS. 1 and 2)
From the throttle opening deviation Δθ calculated in the above, a throttle actuator output value u to a throttle actuator (not shown) is calculated by:

[Equation 11] Is calculated by In Equation 11, the first, second, and third terms on the right side are feedback terms in the PID control, and k _P , k _I, and k _D are proportional gains, respectively.
Integral gain and derivative gain.

Next, at step 404, the throttle opening control device 5 (FIGS. 1 and 2)
The throttle actuator output value u calculated in (1) is output to a throttle control motor (not shown), and this routine ends.

FIG. 10 is a flowchart of the control program executed in step 114 of the flowchart of FIG. In this routine, the acceleration / deceleration estimated value is considered in consideration of the engine map, the torque ratio of the torque converter (not shown), the gear ratio of the differential gear 18 (FIG. 1), a constant vehicle weight, and the vehicle resistance obtained from the map. Calculate g.

First, in step 601, the actual throttle opening θ is read. Thereafter, in step 602, the actual throttle opening θ and the engine speed N
_The engine torque τ _eng is calculated from _eng . That is,
The engine torque τ _eng is

Τ _eng = f _eng (θ, N _eng ) This will be described later in detail with reference to FIG.

Next, in step 603, an estimated wheel torque value τ _whl is calculated by multiplying the engine torque τ _eng by the torque ratio ηt and the gear ratio _ηg . Therefore, the estimated wheel torque τ _whl is

_Equation 13: τ _whl = τ _eng ηtηg

Next, at step 604, acceleration / deceleration is performed.
Degree estimated value g, wheel torque estimated value τ _whl, Vehicle weight m,
Wheel radius r, road surface gradient g_gAnd running resistance g_rCalculated from
Then, this routine ends. Therefore, the acceleration / deceleration estimation
The value g is

The [number 14] _{g = τ whl / rm-g} g -g r.

FIG. 11 is a flowchart of the control program executed in step 116 of the flowchart of FIG. In this routine, the target brake hydraulic pressure p ^* is calculated from the required target acceleration / deceleration g ^* calculated in step 301 and the estimated acceleration / deceleration g calculated in step 114.

In this routine, first, in step 501, the brake fluid pressure control device 19 (FIGS. 3 and 4) sets the target acceleration / deceleration g ^* calculated in step 301 and step 1
From the acceleration / deceleration estimated value g calculated in 14, the acceleration / deceleration deviation Δ
Calculate g. Therefore, the acceleration / deceleration deviation Δg is

Δg = g ^* −g

Next, at step 502, the braking fluid pressure control device 19 (FIGS. 3 and 4) calculates the target braking pressure torque τ ^* from the wheel radius r, the vehicle weight m and the acceleration / deceleration deviation Δg ^.
_{Calculate whlbrk} . Therefore, the target braking pressure torque τ ^*
_whlbrk is

Τ ^* _whlbrk = rmΔg / 2

Next, at step 503, the target system
Hydraulic pressure p^*With the target braking pressure torque τ ^* _whlbrkTo the constant -k
, And terminate this routine.
You. Therefore, the target braking fluid pressure p^*Is

[Mathematical _formula -see _original document] p ^* =-k [tau] ^* _whlbrk . Here, k is a conversion gain. This value is set to a relatively small value so that no abrupt change occurs.

FIG. 12 is a flowchart of the control program executed in step 117 of the flowchart of FIG. In this routine, a command value is output to the brake fluid pressure control device 19 (FIGS. 3 and 4) so that the brake fluid pressure (actual pressure) p becomes the target brake fluid pressure p ^* .

First, in step 701, the brake fluid pressure p is read by a pressure sensor (not shown).

Next, at step 702, the step
Target brake fluid pressure p calculated in step 503 ^*And the braking fluid pressure p
The braking fluid pressure deviation Δp is

## EQU18 ## Calculated as Δp = p ^* −p.

Next, at step 703, it is determined whether or not the braking fluid pressure deviation Δp calculated at step 702 is zero. If the brake fluid pressure deviation Δp is zero, a holding command is issued to the brake fluid pressure control device 19 (FIGS. 3 and 4) in step 704, and this routine ends.

On the other hand, if the brake fluid pressure deviation Δp is not zero, then in step 705, the brake fluid pressure deviation Δp
It is determined whether p is greater than zero. If the brake fluid pressure deviation Δp is larger than zero, in step 706, a pressure increase command is issued to the brake fluid pressure control device 19 (FIGS. 3 and 4) to end the present routine, and the brake fluid pressure deviation Δp becomes smaller than zero. If not, in step 707, a pressure reduction command is issued to the brake fluid pressure control device 19 (FIGS. 3 and 4), and this routine ends.

FIG. 13 is a diagram showing the relationship between the speed ratio and the torque ratio. This relationship is stored in advance in the memory of the computer, and in step 305, the torque ratio ηt is calculated from the speed ratio e.

FIG. 14 is a diagram showing the relationship among the engine speed, the engine torque and the throttle opening. This relationship is stored in advance in the memory of the computer, and in step 308, the target throttle opening θ ^* is calculated from the target engine torque τ _eng ^* and the engine speed N _eng , and in step 602, the throttle opening θ and the engine speed are calculated. The engine torque τ _eng is calculated from the number N _eng .

By performing the control described above, FIG.
When the own vehicle 1 changes lanes from the driving lane 4 to the driving lane 5 as described in the above, the own vehicle 1 detects the actual inter-vehicle distances between the preceding vehicle 2 and the preceding vehicle 3 respectively. During the lane change of the host vehicle 1 from the traveling lane 4 to the traveling lane 5, the target acceleration / deceleration for the inter-vehicle control for the preceding vehicle 2 traveling on the original traveling lane 4 and the traveling lane 5 after the lane change are changed. The target acceleration / deceleration for the inter-vehicle control with respect to the traveling preceding vehicle 3 is calculated, and the calculated target acceleration / deceleration is selected to control the own vehicle 1 by selecting the smaller target acceleration / deceleration.

As a result, for example, when the preceding vehicle 3 is closer to the preceding vehicle 2 or running at a lower vehicle speed, the target acceleration / deceleration for the headway control for the preceding vehicle 3 is calculated to be smaller. It is selected as the target acceleration / deceleration for vehicle control. Thereby, the inter-vehicle distance to the preceding vehicle 3 is maintained at an appropriate value. In addition, the inter-vehicle distance with the preceding vehicle 2 is maintained at or above an appropriate value. In addition, since the vehicle is decelerated in advance during the lane change, it is possible to prevent a large deceleration G from occurring immediately after the lane change is completed in order to maintain a proper inter-vehicle distance with the preceding vehicle 3 and to give the occupant an uncomfortable feeling. .

On the other hand, when the preceding vehicle 2 is closer to the preceding vehicle 3 or running at a lower vehicle speed, the target acceleration / deceleration for the headway control for the preceding vehicle 2 is calculated to be smaller, and It is selected as the target acceleration / deceleration for control. Thereby, the inter-vehicle distance to the preceding vehicle 2 is maintained at an appropriate value. Further, the inter-vehicle distance to the preceding vehicle 3 is maintained at or above an appropriate value.

In any case, the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2 and between the host vehicle 1 and the preceding vehicle 3 can be maintained at least at an appropriate value while the lane of the host vehicle 1 is changing. . Further, when the vehicle speed of the preceding vehicle 3 is low, occurrence of a large deceleration G after the lane change can be prevented.

Further, as shown in FIG. 2, when the preceding vehicle 7 changes lanes from the traveling lane 9 to the traveling lane 10 while the own vehicle 6 is following the preceding vehicle 7, the own vehicle 6
And the actual inter-vehicle distance to the preceding vehicle 8 is detected. During the lane change of the preceding vehicle 7 from the traveling lane 9 to the traveling lane 10, the target acceleration / deceleration for the inter-vehicle control with respect to the original preceding vehicle 7 and the target for the inter-vehicle control with respect to the preceding vehicle 8 after the lane change. The acceleration / deceleration is calculated, and the calculated target acceleration / deceleration is selected to control the host vehicle 1.

As a result, for example, when the vehicle speed of the preceding vehicle 8 is much lower than the vehicle speed of the preceding vehicle 7,
The target acceleration / deceleration for inter-vehicle control is calculated to be small, and is selected as the target acceleration / deceleration for vehicle control.
Thereby, the inter-vehicle distance with the preceding vehicle 8 is maintained at an appropriate value, and the inter-vehicle distance with the preceding vehicle 7 is maintained at or above the appropriate value.
In addition, since the deceleration for the inter-vehicle control is performed on the preceding vehicle 7 in advance while the lane of the preceding vehicle 8 is being changed, the inter-vehicle distance with the preceding vehicle 7 is appropriately maintained immediately after the lane change of the preceding vehicle 8 is completed. This can also prevent the occurrence of a large deceleration G and giving the occupant an uncomfortable feeling.

Even when the preceding vehicle 8 changes lanes while accelerating, the target acceleration / deceleration for the inter-vehicle control with respect to the preceding vehicle 8 is calculated to be small and is selected as the target acceleration / deceleration for vehicle control. . As a result, the preceding vehicle 8
The self-vehicle 6 does not perform unnecessary acceleration even when the vehicle accelerates, and the inter-vehicle distance with the preceding vehicle 7 is appropriately maintained.

Conversely, when the vehicle speed of the preceding vehicle 7 is higher than the vehicle speed of the preceding vehicle 8, the target acceleration / deceleration for the inter-vehicle control with respect to the preceding vehicle 7 is calculated to be small, and is selected as the target acceleration / deceleration for vehicle control. Is done. Thereby, the leading vehicle 7
Is maintained at an appropriate value, and the inter-vehicle distance with the preceding vehicle 8 is maintained at or above the appropriate value.

In any case, during the lane change of the preceding vehicle 7, the own vehicle 6, the preceding vehicle 7 and the own vehicle 6 always change.
The inter-vehicle distance between the vehicle and the preceding vehicle 8 can be kept at least equal to or more than an appropriate value. Further, when the speed of the preceding vehicle 8 is low, it is possible to prevent the occurrence of a large deceleration G after the lane change of the preceding vehicle 7. When the preceding vehicle 8 changes lanes while accelerating, unnecessary acceleration can be prevented.

According to the present embodiment, the calculated target acceleration / deceleration G1. . . By controlling the vehicle 1 (FIG. 3) by selecting the smallest one of the Gn, the vehicle 1 (FIG. 3) may be too close to the preceding vehicle in the next traveling lane while changing the traveling lane. 1 (FIG. 3), the vehicle in the next traveling lane is too close to or separated from the preceding vehicle, the vehicle in the traveling lane changing in the preceding vehicle too close to the vehicle in the traveling lane, After the change of the traveling lane, the vehicle can be prevented from approaching the preceding vehicle too much.
Also, if a slow vehicle exists ahead of the preceding vehicle after the start of the lane change, the vehicle 1 (FIG. 3) starts to decelerate, and the vehicle 1 (FIG. 3) is too close to the preceding vehicle. Can be prevented. Further, these effects can be obtained without performing complicated image processing of recognizing a plurality of traveling lanes and a plurality of vehicles.

When the estimated acceleration / deceleration g is larger than the required target acceleration / deceleration g ^* and the required target acceleration / deceleration g ^* is negative, the start of the brake hydraulic pressure control is determined. The start of the control of the hydraulic pressure can be suitably determined.

Since the target acceleration / deceleration for performing the inter-vehicle control of the vehicle 1 (FIG. 3) is calculated by the PID control using the inter-vehicle distance deviation, the target for performing the inter-vehicle control of the vehicle 11 (FIG. 3) is set. Acceleration / deceleration can be suitably calculated.

[0088] Further, the plurality target acceleration calculation unit 28 (FIG. 4), the target acceleration Gn is used for control of the vehicle 11 (FIG. 3), as the sum of the road surface gradient g _g and the running resistance g _r, required Since the target acceleration / deceleration g ^* is calculated, the required target acceleration / deceleration g ^* can be made more appropriate for the actual running of the vehicle 11 (FIG. 1).

[0089] Further, since considering the road surface gradient g _g and running resistance g _r in determining the acceleration or deceleration estimation value g, it is possible to make them closer to acceleration estimated value g to the actual acceleration and deceleration.

The present invention is not limited to the above-described embodiment, and many modifications and variations are possible. For example, in the above embodiment, the drive system of the vehicle is FR, but another drive system can be used. In addition, the running resistance is calculated using the map, but may be fixed. Further, instead of the scanning type inter-vehicle distance detecting device, another inter-vehicle distance measuring device such as a millimeter wave radar or a laser radar can be used.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a case where a host vehicle changes a traveling lane during control of a vehicle following traveling control device according to the present invention.

FIG. 2 is a diagram for explaining a case where a vehicle preceding a host vehicle changes a traveling lane during control of the vehicle following traveling control device according to the present invention.

FIG. 3 is a system diagram showing a configuration of a vehicle having a vehicle follow-up running control device according to the present invention.

FIG. 4 is a block diagram for illustrating control of a vehicle following travel control device according to the present invention.

FIG. 5 is a flowchart illustrating an operation of the vehicle follow-up traveling control device according to the present invention.

FIG. 6 is a flowchart of a control program executed in step 111 of the flowchart of FIG. 5;

FIG. 7 shows steps 102 and 10 in the flowchart of FIG.
4 is a flowchart of a control program executed in 4 (1), 104 (2), and 104 (n).

FIG. 8 is a flowchart of a control program executed in step 112 of the flowchart of FIG. 5;

FIG. 9 is a flowchart of a control program executed in step 113 of the flowchart of FIG. 5;

FIG. 10 is a flowchart of a control program executed in step 114 of the flowchart of FIG. 5;

FIG. 11 is a flowchart of a control program executed in step 116 of the flowchart of FIG. 5;

FIG. 12 is a flowchart of a control program executed in step 117 of the flowchart of FIG. 5;

FIG. 13 is a diagram showing a relationship between a speed ratio and a torque ratio.

FIG. 14 is a diagram showing a relationship among an engine speed, an engine torque, and a throttle opening.

[Explanation of symbols]

 1,6 own vehicle 2,3,7,8, preceding vehicle 4,5,9,10 traveling lane 11 vehicle 12R, 12L front wheel 13R, 13L rear wheel 14 scan-type inter-vehicle distance detection device 15 throttle opening control device 16 engine Reference Signs List 17 automatic transmission 18 following running control device 19 braking pressure control device 22R, 22L wheel speed detecting device 21L, 21R wheel braking device 22 differential gear 23 brake pedal 24 brake pedal switch 25 CCD camera 26 image processing device 27 target inter-vehicle distance setting device 28 Multiple target acceleration / deceleration calculation device 29 Target acceleration / deceleration calculation device 30 Leading vehicle traveling lane judgment device 31 Own vehicle traveling lane judgment device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // G08G 1/16 G08G 1/16 E

Claims (8)

[Claims] An actual vehicle-to-vehicle distance between a host vehicle and a plurality of preceding vehicles is measured, and a target vehicle-to-vehicle distance between the host vehicle and a plurality of preceding vehicles is set. In the vehicle following travel control device for calculating the target acceleration / deceleration from the inter-vehicle distance deviation and the inter-vehicle distance and controlling the engine output and the braking force of the own vehicle based on the target acceleration / deceleration, A vehicle follow-up running control device, wherein the smallest vehicle is selected to control the own vehicle. 2. Inter-vehicle distance measuring means for measuring actual inter-vehicle distances between the host vehicle and a plurality of preceding vehicles, and target inter-vehicle distance setting means for setting target inter-vehicle distances between the own vehicle and a plurality of preceding vehicles, respectively. Target acceleration / deceleration calculating means for calculating a target acceleration / deceleration from an inter-vehicle distance deviation between the actual inter-vehicle distance and a corresponding target inter-vehicle distance, respectively, and an engine output and a braking force of the host vehicle based on the target acceleration / deceleration. A vehicle following cruise control device comprising an engine output and braking force control means for controlling the vehicle, wherein a target acceleration / deceleration selection means for selecting the smallest one of the target acceleration / deceleration and controlling the own vehicle is provided. A follow-up running control device for a vehicle, comprising: 3. An own vehicle traveling lane and lane change determining means for determining a traveling lane and a lane change of the own vehicle are provided, and the target acceleration / deceleration selecting means is provided by the own vehicle traveling lane and the lane change determining means. 3. The vehicle following travel control device according to claim 2, wherein, when the lane change is determined, the minimum one of the target accelerations / decelerations is selected to control the own vehicle. 4. A preceding vehicle traveling lane and lane change judging means for judging a traveling lane and a lane change of the plurality of preceding vehicles, respectively, wherein the target acceleration / deceleration selecting means is provided for the preceding vehicle traveling lane and lane change judging means. 3. The vehicle according to claim 2, wherein, when a change of at least one of the plurality of preceding vehicles is determined, a minimum one of the target accelerations / decelerations is selected to control the own vehicle. A follow-up running control device for a vehicle, characterized in that: 5. An acceleration / deceleration estimated value calculating means for calculating an estimated acceleration / deceleration estimated value of the host vehicle, and the estimated acceleration / deceleration estimated value is larger than the required target acceleration / deceleration and the required target acceleration / deceleration is calculated. 5. A braking force control start means for judging the start of braking force control by said engine output and braking force control means when the speed is negative, is provided. The follow-up running control device for a vehicle according to any one of the preceding claims. 6. The target acceleration / deceleration calculating means for calculating the target acceleration / deceleration for the inter-vehicle control of the host vehicle by PID control using the inter-vehicle distance deviation. 6. The vehicle following travel control device according to any one of 2 to 5. 7. The target acceleration / deceleration calculating means calculates the required target acceleration / deceleration as a sum of the target acceleration / deceleration, road surface gradient, and running resistance used for controlling the host vehicle. The vehicle follow-up running control device according to any one of claims 2 to 6, wherein: 8. The acceleration / deceleration estimated value calculating means is configured to consider a road surface gradient and a running resistance when obtaining the acceleration / deceleration estimated value. The follow-up running control device for a vehicle according to any one of the preceding claims.