JP2000108717A - Inter-vehicular distance control device, inter-vehicular distance warning device, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent execution of erroneous inter-vehicular distance control if, when inter-vehicular distance control is performed by means of an actual inter-vehicular physical quantity detected on the basis of reflected waves of transmit waves irradiated, the actual inter-vehicular physical quantity does not properly reflect behavior relative to the object of control such as a preceding vehicle. SOLUTION: A change in relative speed is checked to determine whether or not it is abnormal (S404), and if the change in relative speed takes a value considered to be not attainable under a normal controlled condition, the abnormality of the change in relative speed is established (S406: YES). Then whether or not a collision occurred is determined (S405), and if a value that is out of applicability of a control system is detected in a range wherein situation is supposed to be handled by a vehicle driver's control, than a collision is determined to have occurred (S405: YES). If either of those requirements is met, a relative speed abnormality flag is established (S412), and the relative speed is set at 0 km/h (S414). Once the relative speed abnormality flag is established, the request for warning is canceled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-vehicle distance control device for causing a vehicle to run following a preceding vehicle, and an inter-vehicle alarm for executing a warning process for a vehicle driver based on a relationship between the vehicle and the preceding vehicle. Related to devices and the like.

[0002]

2. Description of the Related Art An inter-vehicle control device for automatically following a preceding vehicle has been known as a technique for improving the driving safety of an automobile and reducing the operation burden on a driver. . The method of following is a method of controlling the vehicle so as to eliminate the inter-vehicle deviation which is a difference between the actual inter-vehicle distance between the own vehicle and the preceding vehicle and a preset target inter-vehicle distance. Specifically, a target acceleration is calculated based on the inter-vehicle deviation and the relative speed (the vehicle speed with respect to the preceding vehicle speed), and the acceleration device and the deceleration device are controlled so that the acceleration of the vehicle becomes the target acceleration. You do it.

[0003] It is to be noted that not the inter-vehicle distance itself, but, for example, a value obtained by dividing the inter-vehicle distance by the vehicle speed of the own vehicle (hereinafter, "inter-vehicle time"
Can be realized in the same manner. Further, actually, the preceding vehicle is irradiated with a laser beam or a transmission wave, and the time until the reflected light or the reflected wave is received is calculated to calculate the inter-vehicle distance. The same control may be executed in real time and target time by using the same. Since a physical quantity corresponding to the inter-vehicle distance is feasible in this way, these are also described as “inter-vehicle physical quantity”. However, in the following description of the problem to be solved, the case where the inter-vehicle distance itself is used will be taken as an example.

[0004]

As described above, the relative speed is used when calculating the target acceleration for the headway control. However, the relative speed is not always the relative speed between the preceding vehicle and the host vehicle. It may not be an appropriate indicator of behavior. For example, as illustrated in FIG. 17, on a road having a so-called traveling lane and an overtaking lane, a case where the own vehicle traveling on the traveling lane changes lanes immediately after the vehicle traveling on the overtaking lane. In particular, when the vehicle is a truck or a bus, the inter-vehicle distance sensor detects a front side or a rear side of a truck or a bus as a preceding vehicle newly discovered during a lane change (see FIG. 17 (b)). ),
(C)). Then, the distance data obtained by the inter-vehicle distance sensor and the relative speed calculated using the distance data indicate a state in which the target is approaching rapidly (see FIG. 18).

[0005] Therefore, the target acceleration calculated using the relative speed having a large negative value naturally demands a strong deceleration of the own vehicle, and causes a sudden deceleration which is originally unnecessary. I will. In FIG. 17, it is assumed that the vehicle changes lanes immediately after the vehicle traveling in the adjacent lane. On the contrary, the vehicle traveling in the adjacent lane changes lanes immediately before the vehicle. A similar situation can be assumed.

[0006] In the past, the problem with the inter-vehicle control was mentioned, but when the inter-vehicle distance from the preceding vehicle is shorter than a predetermined warning distance, an alarm is sounded to alert the vehicle driver. A similar problem arises when doing so. That is,
Since this warning distance is set in consideration of the relative speed, if the relative speed becomes a large negative value as described above, an alarm that is not originally required is executed. This can also dilute the alert effect in situations where a true alert is needed.

In view of the above, the present invention provides an inter-vehicle control using an inter-vehicle physical quantity detected based on a reflected wave of an emitted transmission wave, and the actual inter-vehicle physical quantity indicates a relative behavior with a control object such as a preceding vehicle. The first object is to prevent erroneous headway control from being executed when the vehicle speed is not properly reflected.

When an inter-vehicle warning is issued using an inter-vehicle physical quantity detected based on a reflected wave of an emitted transmission wave, the actual inter-vehicle physical quantity appropriately reflects a relative behavior with a control object such as a preceding vehicle. If not, a second object is to prevent an erroneous inter-vehicle warning from being executed and to prevent dilution of an alarm effect due to unnecessary execution of an alarm.

[0009]

According to the first aspect of the present invention, there is provided an inter-vehicle control apparatus for transmitting a transmission wave over a predetermined angle range in a vehicle width direction.
Based on the reflected wave, the actual inter-vehicle physical quantity corresponding to the actual inter-vehicle distance between the own vehicle and the preceding vehicle is detected. And
The relative speed between the own vehicle and the preceding vehicle is calculated based on the detected actual inter-vehicle physical quantity. The inter-vehicle control means calculates an inter-vehicle control amount based on the inter-vehicle deviation which is a difference between a target inter-vehicle physical quantity which is a physical quantity corresponding to a target inter-vehicle distance between the own vehicle and the preceding vehicle, and the calculated relative speed. By controlling the driving of the acceleration unit and the deceleration unit based on the inter-vehicle control amount, the own vehicle follows the preceding vehicle and travels.

It is assumed that such an inter-vehicle control is executed. However, if at least one of the following first condition or second condition is satisfied, the inter-vehicle control means calculates the calculated relative speed. Is not used for headway control. The first condition is that the change in the relative speed calculated by the relative speed calculation means has a value that cannot be generated in a normal control state. This is the case where the degree of deceleration is large enough not to occur in normal control, for example, in view of the performance of the acceleration means and deceleration means. This can be considered as a situation where the relative behavior with respect to the control target such as the preceding vehicle is not appropriately reflected.

The second condition is that the collision time calculated based on the relative speed is a value outside the applicable range on the headway control system. The collision time is the time required to collide with the preceding vehicle when considering the inter-vehicle distance and the relative speed at that time. For example, as shown in claim 2, the relative speed is 0 or a positive value. It is conceivable to calculate the collision time as a value obtained by dividing the actual inter-vehicle distance by the absolute value of the relative speed when the relative speed is infinity, and when the relative speed is a negative value. The “outside the applicable range on the inter-vehicle control system” is, for example, a range assumed to be left to the operation of the vehicle driver, as described in claim 3. For example, in a situation where a full brake is required, it is considered that this is not a range that can be handled by a system for automatically controlling the distance between vehicles, but should be operated by a vehicle driver. This is because it is considered dangerous to automatically apply the full brake in a situation where the vehicle driver does not recognize itself. In other words, the inter-vehicle control does not assume that it is automatically executed in any situation, but realizes automation in a limited situation. Therefore, when the collision time “out of the applicable range on the vehicle-to-vehicle control system” is calculated, it is necessary to determine whether the vehicle driver should handle the collision by his / her own operation or the relative position with the control target such as the preceding vehicle. Can be considered as a situation that does not properly reflect the general behavior.

Therefore, when at least one of the first condition and the second condition is satisfied, the calculated relative speed is not used for the headway control, so that the relative speed with respect to a control object such as a preceding vehicle is reduced. Erroneous inter-vehicle control using the relative speed calculated based on the actual inter-vehicle physical quantity that does not appropriately reflect the dynamic behavior can be prevented. For example, since the detection data at the time of the lane change shown in FIG. 17 corresponds to either the first condition or the second condition, the inter-vehicle control using such abnormal data is not executed. The same effect is also exhibited when a vehicle running in the next lane changes lanes immediately before the own vehicle. And, of course, it is possible to cope with the case where the detection data itself is not normally detected due to the influence of noise or the like.

The reason why “at least one of the first condition and the second condition” is set is that, in consideration of a situation where only one of the conditions is satisfied, it is necessary to minimize use of inappropriate data. To do that. And the first
In a case where at least one of the condition and the second condition is satisfied and the calculated relative speed is not used for the following distance control, for example, the relative speed used for calculating the following distance control amount may be determined. It is conceivable to temporarily fix the speed to a predetermined value. Assuming that the calculation of the inter-vehicle control amount itself is normally performed, the relative speed used for the calculation is fixed to a predetermined value such as 0 km / h instead of based on the detection data. That is, it is a measure at the input stage.

The output stage may deal with this. For example, when at least one of the first condition and the second condition is satisfied, the inter-vehicle control amount is temporarily fixed to a predetermined value.
For example, if the inter-vehicle control amount is the target acceleration, this is set to 0 km
/ H / s. When the inter-vehicle control amount is temporarily fixed to a predetermined value, the inter-vehicle control at the time when at least one of the first condition and the second condition is satisfied is performed as described in claim 6. In the case of the deceleration control state, it is conceivable to release the deceleration control state and then temporarily fix the inter-vehicle control amount to a predetermined value. This is because the immediately preceding deceleration control state may have been executed based on inappropriate detection data, and is therefore cleared once.

By not using the inappropriate relative speed for the following control, it is possible to prevent erroneous following control from being executed, but it is conceivable to take the following measures as follows. . That is, as set forth in claim 7, after the at least one of the first condition and the second condition is satisfied, the headway control unit determines that the relative speed calculated by the relative speed calculation unit is not satisfied. The normal speed of the relative speed is determined by comparing the relative speed calculated using the inter-vehicle physical quantity after the relative speed is reached, and when it is determined that the relative speed is normal, the relative speed or the inter-vehicle control amount is temporarily set to a predetermined value. The fixing is stopped, and the headway control using the relative speed calculated at that time is executed.

An inter-vehicle distance control device according to claim 8 is provided to achieve a second object in addition to the first object. The inter-vehicle alarm means of the inter-vehicle control device is configured to output a predetermined alarm in which an actual inter-vehicle physical quantity, which is a physical quantity corresponding to an actual inter-vehicle distance between the own vehicle and the preceding vehicle, is set based on at least a relative speed between the own vehicle and the preceding vehicle. It is basically determined whether or not the actual vehicle-to-vehicle physical quantity has become smaller than the alarm judgment value, and an alarm process for a vehicle driver is executed. Then, the first
If at least one of the condition and the second condition is satisfied, the calculated relative speed is not used for the alarm determination. In addition, as a method of not using the relative speed for the alarm determination, it is conceivable that the alarm itself is not executed when the relative condition is satisfied, so that the relative speed can be simply realized.

In this way, if the detected actual inter-vehicle physical quantity does not appropriately reflect the relative behavior with the control object such as a preceding vehicle, an erroneous inter-vehicle alarm is prevented from being executed, and an unnecessary alarm is prevented. Dilution of the alarm effect by execution can also be prevented. Since this inter-vehicle warning is executed on the premise of inter-vehicle control, it is considered as the invention of the inter-vehicle control device, but it can also be realized as an inter-vehicle alarm device that achieves only the above-mentioned second object. For example, according to the ninth aspect, a transmission wave is irradiated within a predetermined angle range in the vehicle width direction, and based on the reflected wave, a real vehicle-to-vehicle distance that is a physical quantity corresponding to a real vehicle-to-vehicle distance between the own vehicle and a preceding vehicle. Inter-vehicle physical quantity detection means for detecting a physical quantity, relative speed calculation means for calculating the relative speed between the own vehicle and the preceding vehicle based on the actual inter-vehicle physical quantity detected by the inter-vehicle physical quantity detection means, and the actual inter-vehicle physical quantity, It is determined whether the actual vehicle-to-vehicle physical quantity has become smaller than the warning determination value, and it is determined whether the actual vehicle-to-vehicle physical quantity has become smaller than the predetermined warning determination value based on at least the relative speed between the own vehicle and the preceding vehicle. It is assumed that an inter-vehicle alarm device includes an inter-vehicle alarm unit capable of executing an alarm process for a person. When the at least one of the first condition relating to the relative speed and the second condition relating to the collision time is satisfied, the inter-vehicle warning unit does not use the calculated relative speed for the warning determination. You do it.

In this case, the inter-vehicle warning device also temporarily sets the relative speed used for the warning determination to a predetermined value when at least one of the first condition and the second condition is satisfied. Or, after at least one of the first condition and the second condition is satisfied, the relative speed calculated by the relative speed calculating means is not satisfied. The normal speed of the relative speed is determined by comparing with the relative speed calculated using the following inter-vehicle physical quantity, and when it is determined that the relative speed is normal, the relative speed is temporarily fixed at a predetermined value. It is conceivable to execute an alarm determination using the relative speed calculated at that time. These effects are the same as those in the case of the headway control and will not be described again.

The function of realizing the inter-vehicle control means of the inter-vehicle control device according to any one of claims 1 to 8 or the inter-vehicle alarm means of the inter-vehicle alarm device according to any of claims 9 to 11 by a computer system is as follows. For example, it can be provided as a program to be started on the computer system side. In the case of such a program, for example, it can be used by recording it on a computer-readable recording medium such as a floppy disk, a magneto-optical disk, a CD-ROM, or a hard disk, and loading and activating the computer system as needed. it can. In addition, ROM
The above program is recorded in a computer-readable recording medium such as a computer or a backup RAM.
M or a backup RAM may be incorporated in the computer system and used.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. It is needless to say that the embodiments of the present invention are not limited to the following examples, and can take various forms as long as they belong to the technical scope of the present invention.

[First Embodiment] FIG. 1 shows an electronic control device 2 (hereinafter referred to as "inter-vehicle control ECU") and a brake electronic control device 4 to which the above-mentioned invention is applied.
FIG. 2 is a block diagram illustrating a schematic configuration of various control circuits mounted on the vehicle, mainly showing a (brake ECU).

The inter-vehicle control ECU 2 corresponds to "inter-vehicle control means" and "inter-vehicle warning means", and is an electronic circuit mainly composed of a microcomputer.
n) a signal, a steering angle (str-eng, S0) signal, a yaw rate signal, a target inter-vehicle time signal, wiper switch information, a control state signal for idling control and brake control, and the like. ). The inter-vehicle control ECU 2 performs inter-vehicle control and inter-vehicle warning based on the received data.

The laser radar sensor 3 corresponds to "inter-vehicle physical quantity detecting means" and "relative speed calculating means", and is an electronic circuit mainly composed of a scanning distance measuring device using a laser and a microcomputer. Based on the angle and distance of the preceding vehicle detected by the distance device, the relative speed, the relative acceleration obtained by differentiating the relative speed, the current vehicle speed Vn signal received from the headway control ECU 2, the curve radius of curvature R, and the like. As a part of the inter-vehicle distance control device, the self-lane probability of the preceding vehicle is calculated and transmitted to the inter-vehicle control ECU 2 as preceding vehicle information including information such as relative speed. Further, the diagnosis signal of the laser radar sensor 3 itself is also transmitted to the following distance control ECU 2.

The scanning range finder scans and irradiates a transmission wave or a laser beam to a predetermined angle range in the vehicle width direction, and based on a reflected wave or reflected light from an object,
It functions as "inter-vehicle physical quantity detection means" capable of detecting the distance between the host vehicle and the forward object in accordance with the scan angle.

Further, the following distance control ECU 2 determines the preceding vehicle to be subjected to the following distance control based on the own lane probability and the like included in the preceding vehicle information received from the laser radar sensor 3 as described above, and sets the following distance to the preceding vehicle. As a control command value for appropriately adjusting the target acceleration signal, a target acceleration signal,
It transmits a fuel cut request signal, an OD cut request signal, a third speed shift down request signal, and a brake request signal. Further, it determines the occurrence of an alarm and transmits an alarm request signal. Further, it transmits a diagnosis signal, a display data signal, and the like.

The brake ECU 4 is an electronic circuit mainly composed of a microcomputer, and includes a steering sensor 8 for detecting a steering angle of the vehicle, a yaw rate sensor 10 for detecting a yaw rate, and a wheel speed for detecting the speed of each wheel. From the sensor 12, the steering angle, the yaw rate,
The wheel speed is obtained, and these data are stored in the engine ECU 6.
Is transmitted to the inter-vehicle control ECU 2 via the. Further, the brake ECU 4 performs the following control E via the engine ECU 6.
Control command value from CU2 (target acceleration, brake request)
, A brake driver (not shown) is driven to control the brake hydraulic pressure. Further, the brake ECU 4 sounds an alarm buzzer 14 in response to an alarm request signal from the inter-vehicle control ECU 2 via the engine ECU 6.

The engine ECU 6 is an electronic circuit mainly composed of a microcomputer, and includes a vehicle speed sensor 16 for detecting a vehicle speed, a brake switch 18 for detecting whether or not a brake is depressed, a cruise control switch 20, a cruise main switch 22. , And a throttle opening sensor (not shown), detection signals from other sensors and switches, or body LA.
It receives wiper switch information and tail switch information received via N24, and further receives a steering angle (str-eng, S0) signal and yaw rate signal from the brake ECU 4, a target acceleration signal from the headway control ECU 2 and a fuel cut request. Signals, an OD cut request signal, a third shift down request signal, a brake request signal, an alarm request signal, a diagnosis signal, a display data signal, and the like.

The engine ECU 6 drives a throttle driver, a transmission driver (not shown), and the like in accordance with an operation state determined from the received signal. Also, necessary display information is stored in the body LA.
Via N24, it is transmitted to and displayed on a display device (not shown) such as an LCD, or the current vehicle speed (V
n) A signal, a steering angle (str-eng, S0) signal, a yaw rate signal, a target inter-vehicle time signal, a wiper switch information signal, and a control state signal for idling control and brake control are transmitted to the inter-vehicle control ECU 2.

In this embodiment, the transmission (not shown) is a 5-speed automatic transmission, and the reduction ratio of the 4-speed is set to "1".
5th gear ratio is smaller than 4th gear (eg 0.7)
So-called 4-speed + overdrive (O
D) Configuration.

In this embodiment, the engine EC
U6 corresponds to “acceleration means”, and the engine ECU 6 and the brake ECU 4 correspond to “deceleration means”. Next, FIG.
To the flowchart shown in FIG.
The processing executed in Step 2 will be described.

FIG. 2 is a flowchart showing the main processing. First, in the first step S110, it is determined whether or not the vehicle is currently being controlled.
0: NO), it is determined whether the control start switch has been set (S140). If the cruise control switch 20 has been turned ON, the control start switch has been set. If the control start switch is not set (S140: NO), S110
Then, the main processing is terminated after executing the output at the time of non-control of the acceleration / deceleration device. Details of the output when the acceleration / deceleration device is not controlled in S1100 will be described later.

If control is not being performed (S110: NO),
If the control start switch has been set (S14)
0: YES), and proceeds to S130. In S130, it is determined whether the control end switch has been set. If the cruise control switch 20 has been turned off, the control end switch has been set.
If the control end switch is set (S130: Y
ES), the process proceeds to S1100 to execute the output when the acceleration / deceleration device is not controlled, and then ends the main process.

If the control end switch has not been set (S130: NO), it is determined whether the relative speed is abnormal (S400). Thereafter, the target headway is calculated (S50).
0) Then, the respective processes related to the target acceleration calculation (S600), the inter-vehicle control of the acceleration / deceleration control (S700), and the acceleration / deceleration device drive output (S800) are executed, and the alarm generation determination process (S900) is executed. Then, the main process ends.

The above is the description of the entire processing, and subsequently, S400, S600 to S900 and S11
00 will be described in detail. In the following description, the process related to the relative speed abnormality determination (S400)
3 to 6 are shown in FIGS. 3 to 6, the flowcharts of the respective processes (S600 to S800 and S1100) related to the following distance control are shown in FIGS. 7 to 14, and the flowchart of the processes related to the following distance warning (S900) are shown in FIG. Hereinafter, description will be made in order.

First, the relative speed abnormality determination processing in S400 will be described. First step S401 shown in FIG.
In, it is determined whether there is target data. If there is no target data (S401: NO), S4
The process proceeds to step S11, where the relative speed abnormality flag is not established.

On the other hand, if there is target data (S401: Y
ES), the process proceeds to S402, and it is determined whether or not a predetermined determination time Tw has elapsed after a new target has been found. If Tw seconds have elapsed after the new discovery (S40)
2: YES), proceed to S411 to make the relative speed abnormality flag non-established, but if Tw seconds have not elapsed (S40)
2: NO), and proceeds to S403.

In S403, it is determined whether or not the inter-vehicle distance is shorter than a predetermined determination distance Dth. If the inter-vehicle distance is equal to or longer than the determination distance Dth (S403: N
O), the process proceeds to S411, and the relative speed abnormality flag is not established. If the inter-vehicle distance is less than the determination distance Dth (S),
403: YES), and proceeds to S404.

The determinations in S402 and S403 are made to limit the target for determining the relative speed abnormality to a position near the own vehicle. In other words, as illustrated in FIG. 17, if the vehicle changes lanes, the vehicle is limited to a case in which the lane changes immediately after a vehicle running in the adjacent lane.

Then, in S404, an abnormality in the relative speed change is determined, and in S405, a collision is determined.
These will be described in detail with reference to FIGS. FIG.
Is a relative speed change abnormality determination subroutine in S404. In a first step S4041, a change in the relative speed is calculated. Specifically, it is calculated by dividing a value obtained by subtracting the previous value of the relative speed from the current value of the relative speed by the distance measurement cycle.

At S4042, it is determined whether or not the absolute value of the relative speed change is larger than a predetermined determination value Arth. If the absolute value of the relative speed change is larger than the predetermined determination value Arth (S4042: Y
ES), it is determined that the relative speed change is abnormal (S4).
043), this subroutine ends. On the other hand, if the absolute value of the relative speed change is equal to or smaller than the predetermined determination value Arth (S
4042: NO), it is determined that the abnormality of the relative speed change is not established (S4044), and this subroutine ends.

The state in which the absolute value of the relative speed change is larger than the determination value Arth is a state in which such a relative speed change cannot occur in a normal control state. In other words, this is a case where the value indicates a large acceleration or deceleration that does not occur in normal control in consideration of the performance of the engine and the brake. This can be considered as a situation where the relative behavior of the preceding vehicle is not properly reflected. Therefore, it is determined that the relative speed change is abnormal.

FIG. 5 shows the collision determination subroutine in S405. In a first step S4051, a collision time is calculated. The collision time is the time required until the vehicle collides with the preceding vehicle, considering the inter-vehicle distance and the relative speed at that time. Specifically, when the relative speed is 0 or more, the collision time is infinite and the relative speed is 0. If it is smaller, the distance is calculated by dividing the inter-vehicle distance by the absolute value of the relative speed.

Then, in subsequent S4052, it is determined whether or not the collision time is smaller than a predetermined determination value Tcth. If the collision time is smaller than the predetermined determination value Tcth (S4052: YES), it is determined that the collision determination has been made (S4053), and the present subroutine ends. On the other hand, if the collision time is equal to or longer than the predetermined determination value Tcth (S4052: NO), it is determined that the collision determination is not established (S4054), and this subroutine ends.

When the collision time is shorter than the predetermined judgment value Tcth, it is out of the applicable range on the vehicle-to-vehicle control system. “Out of the applicable range” is a range assumed to be left to the operation of the vehicle driver. For example,
In situations where full braking is required, it is considered that the vehicle driver should operate the vehicle, rather than the range that is automatically controlled by the system for automatically controlling the distance between vehicles. This is because it is considered dangerous to automatically apply the full brake in a situation where the vehicle driver does not recognize itself. In other words, the inter-vehicle control does not assume that it is automatically executed in any situation, but realizes automation in a limited situation. Therefore, when the collision time “out of the applicable range on the vehicle-to-vehicle control system” is calculated, it is necessary to determine whether the vehicle driver should handle the collision by his / her own operation or the relative position with the control target such as the preceding vehicle. Can be considered as a situation that does not properly reflect the general behavior.

Returning to the description of FIG. 3, after the determination of the abnormality in the relative speed change and the determination of the collision are completed in S404 and S405,
In S406, it is determined whether or not the abnormality of the relative speed change has been established. Then, when the abnormality of the relative speed change is established (S406: YES), the process proceeds to S412,
The relative speed abnormality flag is established. On the other hand, when the abnormality of the relative speed change is not established (S406: NO), S407 is performed.
Then, it is determined whether or not the collision determination is made. If the collision determination is made (S407: YE
S), and proceeds to S412. On the other hand, when the collision determination is not established (S407: NO), the process proceeds to S408. That is, if at least one of the abnormality of the relative speed change and the collision determination is established, the process proceeds to S412, and the relative speed abnormality flag is established.

In the following S413, it is determined whether or not the relative speed abnormality flag has been established. If the flag has not been established (S413: NO), this subroutine is terminated as it is, but if it has been established (S413: YES). After setting the relative speed to 0 km / h (S414), this subroutine is terminated.

Also, no abnormality in the relative speed change is established (S
406: NO), when the collision determination is not established (S
407: NO), and proceeds to S408. In S408, it is determined whether or not the relative speed abnormality flag is established. If the relative speed abnormality flag is not established (S408: NO), the process proceeds to S411, and the relative speed abnormality flag is not established. If the relative speed abnormality flag is established (S408: YES), A normality determination process of the relative speed is executed (S409). FIG. 6 is a flowchart showing the relative speed normality determination subroutine in S409.

In the first step S4091, a relative speed for comparison is calculated. The relative speed for comparison is calculated based on the following concept. In the situation where the side of the vehicle is detected as shown in FIGS. 17A to 17C, normal distance data cannot be obtained and an abnormality in the relative speed change is established (S4).
06: NO) or a collision determination is made (S407: N
O). Thereafter, when these determinations are not satisfied, there is a high possibility that the distance data has been normally obtained (see FIG. 17D). Therefore, if the relative speed is calculated using only normal distance data after the abnormality of the relative speed change is not established (S406: YES) or the collision determination is not established (S407: YES), the correct relative speed is obtained. Is considered to be obtained. In this way, the relative speed calculated using only the distance data after when both conditions are not satisfied without using the distance data before when the abnormality of the relative speed change is established or when the collision determination is established is obtained. ,
This is a relative speed for comparison.

Then, in subsequent S4092, it is determined whether or not the absolute value of the value obtained by subtracting the relative speed for comparison from the relative speed calculated at that time is smaller than a predetermined determination value Vrth. If it is smaller than the predetermined determination value Vrth (S4092: YES), it is determined that the relative speed is normal (S4093), and this subroutine is terminated. On the other hand, if it is equal to or more than the predetermined determination value Vrth (S4092:
NO), it is determined that the normal determination of the relative speed is not established (S
4094), this subroutine ends.

Returning to the description of FIG. 3, after the normality determination of the relative speed in S409 is completed, it is determined in S410 whether the normality determination of the relative speed is established, and if it is established (S410: YES) ), After the relative speed abnormality flag is not established in S411, the process proceeds to S413. On the other hand, if the normal determination of the relative speed is not established (S41)
0: NO), and proceeds to S413.

As described above, when at least one of the abnormality in the relative speed change and the collision determination is established, the relative speed abnormality flag is established (S412), and the relative speed is set to 0.
km / h (S414), and then keep the relative speed at 0 km / h until the normal determination of the relative speed is established.

Next, the target acceleration calculation subroutine in S600 will be described with reference to the flowchart of FIG. In the first step S601, it is determined whether or not the preceding vehicle is being recognized. If the preceding vehicle is not being recognized (S601: NO), the value obtained when the preceding vehicle is not confirmed is set as the target acceleration (S609), and the present subroutine ends.

On the other hand, if the preceding vehicle is being recognized (S60)
1: YES), and proceeds to S603 to calculate an inter-vehicle deviation. This inter-vehicle deviation is obtained by subtracting the target inter-vehicle distance from the current inter-vehicle distance. In step S605, the relative speed is calculated. In step S607, the target acceleration is obtained by referring to the control map shown in FIG. 7B based on both the inter-vehicle deviation and the relative speed obtained in steps S603 and S605. Thereafter, this subroutine ends.

Next, the acceleration / deceleration control subroutine in S700 of FIG. 2 will be described with reference to the flowchart of FIG. This acceleration / deceleration control is performed by throttle control (S71).
0), the accelerator off control (S720), the downshift control (S730), and the brake control (S740) are sequentially performed, and the process ends. Each control will be described.

First, the throttle control subroutine of S710 will be described with reference to the flowchart of FIG. In this throttle control, the value obtained by multiplying the acceleration deviation by the throttle control gain K11 is added to the previous throttle opening instruction value to obtain the current throttle opening instruction value (S711). The acceleration deviation is a value obtained by subtracting the target acceleration from the actual acceleration.

Next, the accelerator off control subroutine of S720 will be described with reference to the flowchart of FIG. In the first step S721, it is determined whether or not the acceleration deviation is smaller than the reference value Aref11. If the acceleration deviation is smaller than Aref11 (S721: YES), an accelerator-off operation is instructed (S723), and this subroutine is terminated.

On the other hand, if acceleration deviation ≧ Aref11 (S7
21: NO), and proceeds to S725, where the acceleration deviation is the reference value.
Determine if it is greater than Aref12. If acceleration deviation> Aref12 (S725: YES), an instruction to cancel the accelerator-off operation is issued (S727), and this subroutine ends. If acceleration deviation ≦ Aref12 (S72).
5: NO), and this subroutine ends as it is.

Next, the downshift control subroutine of S730 will be described with reference to the flowchart of FIG. In the first step S731, it is determined whether or not the acceleration deviation is smaller than the reference value Aref21. If the acceleration deviation is smaller than Aref21 (S731: YES), a downshift operation is instructed (S733), and an accelerator off operation instruction is further issued. After that (S735), this subroutine ends. On the other hand, if the acceleration deviation ≧ Aref21 (S731:
NO), proceeding to S737, where the acceleration deviation is equal to the reference value Aref22.
Determine if it is greater than. And the acceleration deviation>
If Aref22 (S737: YES), an instruction to release the downshift operation is issued (S727), and this subroutine is terminated. However, if acceleration deviation ≦ Aref22 (S737: N).
O), the subroutine is terminated as it is.

Next, the brake control subroutine of S740 will be described with reference to the flowchart of FIG. In the first step S741, it is determined whether or not the acceleration deviation is smaller than the reference value Aref31. If the acceleration deviation is smaller than Aref31 (S741: YES), the operation of the brake is instructed (S743), and the operation of the accelerator off operation is instructed (S745). Then, the flow shifts to S751.

On the other hand, if acceleration deviation ≧ Aref31 (S7
41: NO), and proceeds to S747, where the acceleration deviation is the reference value.
Determine if it is greater than Aref32. Then, if the acceleration deviation is greater than Aref32 (S747: YES), an instruction to release the brake operation is issued (S749), and the flow shifts to S751, but if the acceleration deviation ≤ Aref32 (S747:
NO), and it will transfer to S751 as it is.

In S751, it is determined whether or not a brake operation instruction is being given. Then, if the brake operation is being instructed (S751: YES), the flow shifts to S753, where a value obtained by multiplying the acceleration deviation by the throttle control gain K21 is obtained.
The value is added to the previous brake pressure instruction value to obtain the current brake pressure instruction value. On the other hand, if the brake operation is not instructed (S
751: NO), and proceeds to S755 to set the brake pressure instruction value to 0.

After the processing in S753 or S755, the present subroutine ends. Next, the acceleration / deceleration device drive output subroutine in S800 of FIG. 2 will be described with reference to the flowchart of FIG. First step S8
In step 01, it is determined whether or not an accelerator-off operation instruction has been issued. If the accelerator-off operation instruction has not been issued (S801: NO), a drive output for releasing the brake (S803) and a signal for releasing the downshift are released. Drive output (S
805), the feedback drive output of the throttle opening (S807) is sequentially performed, and then this subroutine ends.

On the other hand, if an accelerator off operation instruction has been issued (S801: YES), it is determined whether a downshift operation instruction has been issued. If the shift down operation instruction has not been issued (S809: NO), it is determined whether or not the brake operation instruction has been issued (S81).
1).

If no brake operation instruction is given (S811: NO), a drive output for releasing the brake (S813), a drive output for releasing the downshift (S815), and a signal for completely closing the throttle are provided. After the drive output (S817) is sequentially performed, the present subroutine ends. If a brake operation instruction has been given (S8)
11: YES), the drive output for fully closing the throttle (S819), the drive output for downshift release (S821), and the feedback drive output of brake pressure (S823) are sequentially performed, and then this subroutine is terminated. .

On the other hand, a positive determination is made in S809, that is,
There is an accelerator off operation instruction (S801: YES),
In addition, when there is a shift down operation instruction (S809:
If it is (YES), the process proceeds to S825, and it is determined whether or not a brake operation instruction is given (S811).

If no brake operation instruction has been given (S825: NO), a drive output for releasing the brake (S827), a drive output for fully closing the throttle (S829), and a shift-down drive output (S831). )
Are sequentially performed, and then this subroutine is terminated. Also,
If the brake operation instruction is given (S825: YE
S), a drive output for fully closing the throttle (S83)
3), shift-down drive output (S835), and brake pressure feedback drive output (S837) are sequentially performed, and then this subroutine ends.

Next, the output subroutine at the time of non-control of the acceleration / deceleration device in S1100 will be described with reference to the flowchart of FIG. Since this process is a process when control is not performed on the acceleration / deceleration device, a drive output for fully closing the throttle in S1101, a drive output for releasing the downshift in S1103, and a drive output for releasing the brake in S1105. Are sequentially performed, and this subroutine is terminated.

Next, the subroutine of the alarm occurrence determination process in S900 of FIG. 2 will be described with reference to the flowchart of FIG. In the first step S901, it is determined whether or not the preceding vehicle is being recognized. If recognition is not being performed (S901: NO), the alarm request is released (S90).
9) The subroutine ends. If the preceding vehicle is being recognized (S901: YES), the process proceeds to S902.

In S902, it is determined whether or not the relative speed abnormality flag is established. This relative speed abnormality flag is established in S412 of FIG. 3 and is not established in S411. If the relative speed abnormality flag is established (S902: YES), the alarm request is canceled (S90).
9) The subroutine ends. If the subroutine is not established (S902: YES), the process proceeds to S903.

In S903, it is determined whether or not an alarm request is being instructed. If it is not instructed (S903: NO),
The warning distance is calculated (S904). This warning distance is calculated according to the vehicle speed and the relative speed as shown in the following calculation formula. Warning distance = f (vehicle speed, relative speed) Next, it is determined whether the inter-vehicle distance is shorter than the warning distance (S905). If the inter-vehicle distance is equal to or longer than the warning distance (S905: NO), this subroutine is performed as it is. Is terminated, but if the following distance is shorter than the warning distance (S905:
(YES), an alarm request instruction is issued (S906), and this subroutine ends.

On the other hand, if an alarm request instruction is being issued (S90
3: YES), it is determined whether one second has elapsed since the start of the warning request instruction (S907). If one second has not elapsed (S907: NO), this subroutine is terminated as it is, but if one second has elapsed (S907: Y
ES), and proceeds to S908.

In S908, it is determined whether or not the inter-vehicle distance has exceeded the warning distance. If the following distance is not equal to or longer than the warning distance (S908: NO), this subroutine is terminated as it is. If the following distance is equal to or greater than the warning distance (S908: YES), the warning request is canceled in S909. Then, this subroutine ends.

The above has described the details of the processing of the inter-vehicle control and the inter-vehicle warning by the system of the present embodiment. Next, the effect of the execution of the processing will be described. In the present embodiment, as shown in the flowchart of FIG. 3, the abnormality determination of the relative speed change (S404) and the collision determination (S40)
5), and the relative speed change abnormality is established (S406: Y)
ES) or when the collision determination is made (S405: YES), the relative speed abnormality flag is made (S41).
2) The relative speed is set to 0 km / h (S414).

When an abnormality in the relative speed change is established, the change in the relative speed is considered to be a value that cannot be generated in a normal control state. This is the case where the degree of deceleration is large enough not to occur under normal control. This can be considered as a situation where the relative behavior with respect to the control target such as the preceding vehicle is not appropriately reflected. Further, when the collision determination is established, the value is out of the applicable range on the control system, and is a range assumed to be left to the operation of the vehicle driver.

Therefore, if at least one of the relative speed change abnormality (first condition) and the collision determination (second condition) is established and the relative speed abnormality flag is established, the calculated relative speed Instead, set the relative speed to 0km
/ H (see S414 in FIG. 3) is used for headway control. When the relative speed abnormality flag is established, the alarm request is canceled (see S909 in FIG. 15). That is,
It is possible to prevent erroneous inter-vehicle control or inter-vehicle warning using a relative speed that does not appropriately reflect a relative behavior with a control target such as a preceding vehicle.

For example, as shown in FIG. 17, when the vehicle changes lanes, the relative speed calculated based on the data detected based on the laser light reflected on the side surface of the truck in the adjacent lane is as follows: Since the change cannot be generated by the normal control as shown in FIG.
Condition) or at least one of collision determination (second condition). Therefore, headway control and headway warning using such abnormal data are not executed. The same effect is also exhibited when a vehicle running in the next lane changes lanes immediately before the own vehicle. And, of course, it is possible to cope with the case where the detection data itself is not normally detected due to the influence of noise or the like. And, it is effective not to execute an erroneous inter-vehicle alarm in terms of preventing dilution of an alarm effect by unnecessary alarm execution.

The reason why the relative speed is determined to be abnormal when at least one of the relative speed change abnormality (first condition) and the collision determination (second condition) is established is as follows. In consideration of a situation in which only one of them is established, it is to minimize use of inappropriate data.

Further, in this embodiment, as a countermeasure after the execution of the inter-vehicle control or the inter-vehicle warning based on the improper relative speed, the relative speed normality determination is made in S409 of FIG. That is, once the abnormality of the relative speed change or the collision determination is established, the abnormality of the relative speed change is not established (S406: NO) and the collision determination is not established (S406).
Even if it is 407: NO), the relative speed abnormality flag is not established only if the normality determination is established as a result of the relative speed normality determination in S409 (S410: YES) (S411). If the relative speed abnormality flag does not hold, the fixing of the relative speed to 0 km / h is stopped in S414. Therefore, the headway control using the relative speed calculated at that time is executed, and the headway warning is also processed as usual.

[Second Embodiment] In the first embodiment described above,
When an inappropriate relative speed is output, the relative speed is temporarily set to a predetermined value (0 km / km in the embodiment) in order not to execute the following control or the following warning based on the relative speed.
h). That is, the relative speed used for the calculation of the target acceleration, which is the inter-vehicle control amount, and the arithmetic expression itself for determining the inter-vehicle warning is fixed at a predetermined value. This is a measure at the input stage.

The output stage may cope with this. A case where a measure is taken in the output stage will be described as a second embodiment. FIG. 16 is a flowchart showing the main processing in the case of the second embodiment. The configuration of the system (see FIG. 1) is the same as that of the first embodiment, and a description thereof will be omitted.

S5110 to S5140 in FIG.
Are respectively S110, S140, S13 shown in FIG.
0, the same processing as S400. That is, it is determined in S5110 whether or not the control is currently being performed. If not currently being controlled (S5110: NO), it is determined whether or not the control start switch has been set (S5120). If the control start switch is not set (S512)
0: NO), and proceeds to S5220 to execute the output when the acceleration / deceleration device is not controlled, and thereafter ends this main processing. In addition,
The output processing in S5220 when the acceleration / deceleration device is not controlled is the same processing as S1100 in FIG.

Also, the control is not being performed (S5110: N
O), if the control start switch has been set (S
5120: YES), and proceeds to S5130. S513
At 0, it is determined whether or not the control end switch has been set, and if the control end switch has been set (S51).
30: YES), proceed to S5220 to execute the output when the acceleration / deceleration device is not controlled, and then end the main process.

If the control end switch is not set (S5130: NO), the relative speed is determined to be abnormal (S5140). This processing is the same as the processing of S400 in FIG. 2 (that is, the processing whose details are shown in FIG. 3), and when the abnormality of the relative speed change is established or the collision determination is established as described above. , A relative speed abnormality flag is established.

Then, in the case of FIG. 2, the processing has directly shifted to the processing relating to the following control and the following warning.
In the case of the embodiment, it is determined in subsequent S5150 whether or not the relative speed abnormality flag is established. If the relative speed abnormality flag is not established (S5150:
NO), S5160, S5170, S5180, S51
90S, 5200, S500, S in FIG.
The same processing as in steps 600, S700, S800, and S900 is performed. In other words, the target inter-vehicle distance is calculated (S5160), the target acceleration calculation (S5170), the various processes related to the inter-vehicle control of the acceleration / deceleration control (S5180) and the acceleration / deceleration device drive output (S5190) are executed, and further, the alarm generation determination process ( S52
00), and the main process ends.

On the other hand, if affirmative determination is made in S5150, that is, if the relative speed abnormality flag is not established (S515)
0: NO), and proceeds to S5210 to release all the deceleration requests, ie, the fuel cut (F / C) request, the overdrive (OD) cut request, the shift down request, and the brake request, and set the target acceleration to 0 km / h. Alternatively, it is set to a value in the vicinity. Thereafter, the flow shifts to S5200.

That is, when the relative speed abnormality flag is established, the normal output related processing (S5160 to S51)
Instead of executing step 90), in step S5210, a process of releasing the deceleration request itself and setting the target acceleration to 0 km / h / s or a value in the vicinity thereof is performed. The reason why the deceleration request is canceled is that the immediately preceding deceleration control state may have been executed based on inappropriate detection data, so that it is temporarily cleared.

As described above, even by devising the output stage, erroneous headway control or headway warning using a relative speed that does not appropriately reflect the relative behavior with the control target such as the preceding vehicle is not executed. You can do it. that's all,
The present invention is not limited to such embodiments at all, and can be implemented in various forms without departing from the gist of the present invention.

(1) In the first or second embodiment, since the processing relating to the headway warning (S900 in FIG. 2 or S5200 in FIG. 16) is executed on the premise of headway control, the headway control device Although the present invention has been described as an invention, it may be configured as a device that realizes only the following distance warning. In that case, S400 in FIG. 2 or FIG.
After performing the relative speed abnormality determination in S5140,
The process may immediately shift to the process of S900 in FIG. 2 or S5200 in FIG.

(2) In the above embodiment, the “equivalent value for the following distance”
Although the inter-vehicle distance was used as it is, the same control may be executed at the detected real time and the target time using time as a physical quantity corresponding to the inter-vehicle distance, or the inter-vehicle distance may be used as another physical quantity. Similar control may be executed between the actual inter-vehicle time and the target inter-vehicle time using the time (a value obtained by dividing the inter-vehicle distance by the vehicle speed of the own vehicle). When the target inter-vehicle distance is variable depending on the vehicle speed and the target inter-vehicle distance is set substantially in proportion to the vehicle speed, the target time or the target inter-vehicle time is adjusted instead of adjusting the target inter-vehicle distance. However, the same effect can be obtained.

(3) In the above embodiment, the target acceleration is used as the inter-vehicle control amount. However, the target torque or the target relative speed may be used instead.

[Brief description of the drawings]

FIG. 1 is a system block diagram of an inter-vehicle control device according to an embodiment.

FIG. 2 is a flowchart showing a main process of the headway control.

FIG. 3 is a flowchart illustrating a relative speed abnormality determination subroutine executed during a main process.

FIG. 4 is a flowchart showing a relative speed change abnormality determination subroutine executed during the relative speed abnormality determination.

FIG. 5 is a flowchart showing a collision determination subroutine executed during relative speed abnormality determination.

FIG. 6 is a flowchart illustrating a relative speed normality determination subroutine executed during relative speed abnormality determination.

FIG. 7A is a flowchart illustrating a target acceleration calculation subroutine executed during the main processing, and FIG. 7B is an explanatory diagram of a control map used for target acceleration calculation.

FIG. 8 is a flowchart showing an acceleration / deceleration control subroutine executed during the main processing.

FIG. 9 is a flowchart showing a throttle control subroutine executed during acceleration / deceleration control.

FIG. 10 is a flowchart showing an accelerator-off control subroutine executed during acceleration / deceleration control.

FIG. 11 is a flowchart showing a downshift control subroutine executed during acceleration / deceleration control.

FIG. 12 is a flowchart illustrating a brake control subroutine executed during acceleration / deceleration control.

FIG. 13 is a flowchart showing an acceleration / deceleration device drive output subroutine executed during the main processing.

FIG. 14 is a flowchart showing an acceleration / deceleration device non-control output subroutine executed during the main processing.

FIG. 15 is a flowchart illustrating an alarm occurrence determination subroutine executed during the main processing.

FIG. 16 is a flowchart showing a main process of the headway control according to another embodiment.

FIG. 17 is an explanatory diagram of a situation example where an abnormal relative speed is detected.

18 is an explanatory diagram of an inter-vehicle distance and a relative speed in the example of the situation of FIG. 17;

[Explanation of symbols]

 2: Electronic control device for inter-vehicle control (inter-vehicle control ECU) 3 ... Laser radar sensor 4 ... Electronic brake control device (brake ECU) 6 ... Electronic electronic control device (engine ECU) 8 ... Steering sensor 10 ... Yaw rate sensor 12 ... Wheel speed Sensor 14 Alarm buzzer 16 Vehicle speed sensor 18 Brake switch 20 Cruise control switch 22 Cruise main switch 24 Body LAN

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Eiji Teramura 1-1-1 Showa-cho, Kariya-shi, Aichi F-term in DENSO Corporation (reference) 3D044 AA25 AA33 AA35 AB01 AC24 AC26 AC28 AC59 AD04 AD12 AD17 AD21 AE04 AE15 AE21 3G093 AA01 AA05 BA23 BA27 CB07 CB10 DB05 DB15 DB16 DB21 EA09 EB03 EB04 FA06 FB05 5H180 AA01 CC03 CC14 LL01 LL04 LL07 LL08 LL09

Claims (13)

[Claims] An acceleration means and a deceleration means which can be driven irrespective of an acceleration operation and a braking operation by a vehicle driver, a transmission wave is irradiated over a predetermined angle range in a vehicle width direction, and a self-wave is transmitted based on the reflected wave. A vehicle-to-vehicle physical quantity detecting means for detecting a physical inter-vehicle physical quantity which is a physical quantity corresponding to a physical inter-vehicle distance between the car and the preceding vehicle; and A relative speed calculating means for calculating a relative speed, an inter-vehicle deviation which is a difference between a target inter-vehicle physical quantity which is a physical quantity corresponding to a target inter-vehicle distance between the own vehicle and the preceding vehicle, and a relative calculated by the relative speed calculating means. A vehicle-to-vehicle control amount that is calculated based on the speed, and by controlling the driving of the acceleration unit and the deceleration unit based on the calculated vehicle-to-vehicle control amount, a vehicle-to-vehicle control unit that causes the own vehicle to run following the preceding vehicle; Equipment In the headway control device described above, the headway control means includes a first condition in which a change in the relative speed calculated by the relative speed calculation means is a value considered to be impossible to occur in a normal control state, or When at least one of the second conditions that the collision time calculated based on the relative speed is a value outside the applicable range on the headway control system is satisfied, the calculated relative speed is used as the headway control. Not to be used, a headway distance control device. 2. The inter-vehicle control device according to claim 1, wherein the collision time is infinite when the relative speed is 0 or a positive value, and the collision time is when the relative speed is a negative value. A distance calculated by dividing the distance by an absolute value of the relative speed. 3. The inter-vehicle control device according to claim 1, wherein the range outside the range of the inter-vehicle control system is a range assumed to be left to the operation of a vehicle driver. Characteristic inter-vehicle distance control device. 4. The headway distance control device according to claim 1, wherein the headway distance control means is configured to control the headway distance control when at least one of the first condition and the second condition is satisfied. The inter-vehicle distance control device characterized by temporarily fixing a relative speed used for calculating a predetermined value to a predetermined value. 5. The headway distance control device according to claim 1, wherein the headway distance control means is configured to control the headway distance when at least one of the first condition and the second condition is satisfied. A headway distance is fixed to a predetermined value temporarily. 6. The headway distance control device according to claim 5, wherein the headway distance control means reduces the headway distance control at that time when at least one of the first condition and the second condition is satisfied. If the state is the state, the deceleration control state is released, and then the inter-vehicle control amount is temporarily fixed to a predetermined value. 7. The inter-vehicle distance control device according to claim 1, wherein the inter-vehicle distance control unit is configured to execute the relative speed calculation unit after at least one of the first condition and the second condition is satisfied. If the calculated relative speed is compared with the relative speed calculated using the inter-vehicle physical quantity after all of the above conditions are not satisfied, the relative speed is determined to be normal, and if it is determined that the relative speed is normal, Stop temporarily fixing the relative speed or the inter-vehicle control amount to a predetermined value,
Performing inter-vehicle control using the relative speed calculated at that time, 8. The inter-vehicle control device according to claim 1, further comprising: a real inter-vehicle physical quantity corresponding to a real inter-vehicle distance between the own vehicle and the preceding vehicle, wherein at least It is possible to determine whether the actual inter-vehicle physical quantity has become smaller than the alarm determination value, and determine whether the actual inter-vehicle physical quantity has become smaller than the alarm determination value. The vehicle-to-vehicle warning means, wherein when at least one of the first condition or the second condition is satisfied, the calculated relative speed is not used for the warning determination. Characteristic inter-vehicle control device. 9. An inter-vehicle for irradiating a transmission wave over a predetermined angle range in the vehicle width direction and detecting a physical inter-vehicle physical quantity corresponding to a real inter-vehicle distance between the own vehicle and a preceding vehicle based on the reflected wave. Physical quantity detection means, relative speed calculation means for calculating the relative speed between the own vehicle and the preceding vehicle based on the actual inter-vehicle physical quantity detected by the inter-vehicle physical quantity detection means, and wherein the actual inter-vehicle physical quantity is at least It is determined whether it has become smaller than a predetermined warning determination value set based on the relative speed with the vehicle, and when the actual inter-vehicle physical quantity has become smaller than the warning determination value, a warning process for the vehicle driver is performed. An inter-vehicle warning device including an inter-vehicle warning device that can be executed, wherein the inter-vehicle warning device is considered that a change in the relative speed calculated by the relative speed calculation device cannot occur in a normal control state. If at least one of the first condition to be a value or the collision time calculated based on the relative speed becomes a value outside the applicable range on the headway control system, The calculated relative speed is not used for the alarm determination, an inter-vehicle alarm device. 10. The inter-vehicle warning device according to claim 9, wherein the at least one inter-vehicle warning means temporarily determines a relative speed used for the warning determination when at least one of the first condition and the second condition is satisfied. Inter-vehicle warning device, characterized in that: 11. The inter-vehicle distance control device according to claim 9, wherein the inter-vehicle warning means is calculated by the relative speed calculation means after at least one of the first condition and the second condition is satisfied. The relative speed is compared with the relative speed calculated using the inter-vehicle physical quantity after all of the above conditions are not satisfied to determine whether the relative speed is normal, and when it is determined that the relative speed is normal, the relative speed is determined. Inter-vehicle warning device, characterized by: stopping temporarily fixing the speed to a predetermined value, and executing a warning determination using the relative speed calculated at that time. 12. A computer-readable recording medium in which a program for causing a computer system to function as an inter-vehicle control means of the inter-vehicle control device according to claim 1 is recorded. 13. A computer-readable recording medium on which a program for causing a computer system to function as an inter-vehicle warning device of the inter-vehicle warning device according to claim 9 is recorded.