JP2000284048A - Monitoring device around vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more accurately detect the relative position relationship with a succeeding vehicle by calculating an azimuth from a vehicle regarding an object that commonly exists in first and second overlapped monitoring areas based on each information that is calculated by first and second operation means. SOLUTION: A right outer radar sensor PRO 12 and a right inner radar sensor PRI 14 are installed at a right corner part on a rear bumper of a vehicle 100, and at the same time a left outer radar sensor RLO 16 and a left inner radar sensor RLI 18 are installed at the left corner of the rear bumper. Each of radar sensors 12, 14, 16, and 18 outputs a pulse wave to a corresponding monitoring area, and receives a reflection pulse from the succeeding vehicle when the succeeding vehicle exists within the monitoring area. Then, a detection signal corresponding to the received reflection pulse is outputted from the radar sensors 12, 14, 16, and 18. A control unit 30 calculates distance to the succeeding vehicle within the monitoring area based on the difference between the output timing of the pulse wave from each of the radar sensors 12, 14, 16, and 18 and the reception timing of the reflection pulse.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle periphery monitoring device for monitoring a rear side of a running vehicle, and more particularly to detecting a distance and a relative speed of another vehicle approaching from behind the vehicle by a radar sensor. The present invention also relates to a vehicle periphery monitoring device that determines a relative positional relationship with another vehicle based on the detection information and provides the driver with information based on the determination information.

[0002]

2. Description of the Related Art Conventionally, a vehicle-mounted radar module has been proposed which is provided with a proximity warning antenna for monitoring a rear side area of a vehicle and a distance warning antenna separately (Japanese Patent Application Laid-Open No. 8-152470). According to such an in-vehicle radar module, it is possible to determine, based on a radar detection signal, that a following vehicle has entered a near warning area or a far warning area determined by each antenna.

[0003]

In the above-described conventional apparatus for detecting a following vehicle traveling behind a vehicle, the shape of the alert area cannot be accurately controlled, and the relative position between the concerned vehicle and the following vehicle cannot be controlled. Cannot be accurately detected. For example, it is difficult to accurately form a warning area so as to match an adjacent lane. Even if a warning area mainly covering an adjacent lane is set, the warning area includes a part of the same lane as the vehicle. In addition, a lane portion that is further adjacent to the adjacent lane is included. Therefore, even if it is detected that the following vehicle has entered the warning area, it cannot be accurately determined whether or not the vehicle is traveling in an adjacent lane. The information as to whether or not the following vehicle is traveling in the adjacent lane is useful information for the driver to safely change lanes.

As described above, providing the driver with a more accurate relative positional relationship between the host vehicle and the following vehicle is necessary.
This is useful for reducing the burden on the driver's driving operation.
Accordingly, an object of the present invention is to provide a vehicle periphery monitoring device capable of detecting a relative positional relationship with a following vehicle with higher accuracy.

[0005]

In order to solve the above-mentioned problems,
The present invention provides a vehicle periphery monitoring device that detects a relative positional relationship with an object on a rear side of a vehicle by using a radar sensor that detects a distance to the object, as described in claim 1. A first radar sensor that is installed at the rear of the vehicle and forms a first monitoring area on the rear side of the vehicle, and is installed at a different position from the first radar sensor at the rear of the vehicle. With, a second radar sensor forming a second monitoring area overlapping with the first monitoring area, an object in the first monitoring area and the vehicle based on a detection signal from the first radar sensor. First computing means for computing information dependent on the relative position of the vehicle, and dependent on the relative position of the object in the second monitoring area and the vehicle based on a detection signal from the second radar sensor. The second act of calculating the information Means and a direction from the vehicle of an object commonly existing in the overlapping first and second monitoring areas is calculated based on each information calculated by the first and second calculation means. Azimuth calculating means.

[0006] In such a vehicle periphery monitoring device, since the installation positions of the first radar sensor and the second radar sensor are different, they are commonly present in the overlapping first monitoring area and second monitoring area. Information that depends on the relative position of the object and the vehicle is obtained based on a detection signal from the first radar sensor, and obtained based on a detection signal from the second radar sensor. different.
This difference is due to the difference between the direction in which the first radar sensor faces the object and the direction in which the second radar sensor faces the same object. The azimuth of the object from the vehicle is determined based on the information calculated based on the detection signals from the first and second radar sensors having the difference and the relative position of the object and the vehicle. Is calculated.

The above object is generally another vehicle (follower vehicle) running behind the vehicle, but the type of the vehicle is not particularly limited. Further, the information depending on the relative position between the object and the vehicle calculated by the first and second calculation means is not particularly limited as long as it depends on the relative position. For example, the distance (relative distance) between the vehicle and the object, the relative speed of the object to the vehicle, and the like can be used as the information.

When the relative speed of the object with respect to the vehicle is used as the information depending on the relative position between the object and the vehicle, the present invention relates to a vehicle periphery monitoring apparatus according to the present invention. The first calculating means calculates a relative speed of the object with respect to the vehicle based on a detection signal from the first radar sensor as information depending on a relative position of the object, and performs the second calculation. The means also calculates the relative speed of the object to the vehicle based on the detection signal from the second radar sensor as information depending on the relative position of the object, and the azimuth calculating means includes:
A relative speed ratio calculating means for calculating a ratio between the relative speeds calculated by the first calculating means and the second calculating means; and a relative speed ratio calculating means for calculating a ratio between the relative speeds calculated by the relative speed ratio calculating means. And a relative speed ratio corresponding direction calculating means for calculating the direction of the object from the vehicle.

Further, when the distance (relative distance) between the object and the vehicle is used as the information depending on the relative position between the object and the vehicle, the present invention provides, The first calculating means calculates a relative distance between the object and the vehicle as information depending on a relative position of the object based on a detection signal from the first radar sensor, and performs the second calculation. The means also calculates the relative distance between the object and the vehicle as information depending on the relative position of the object based on the detection signal from the second radar sensor. Relative distance ratio calculating means for calculating a ratio of each relative distance calculated by the second calculating means; and an azimuth of the object from the vehicle based on the ratio of each relative distance calculated by the relative distance ratio calculating means. Computing relative distance It may be configured to and a position calculating means.

In particular, when the relative speed between the object and the vehicle is small, it is difficult to detect the azimuth with high accuracy. For this reason, in a device that uses the relative speed between the object and the vehicle as information depending on the relative position between the object and the vehicle, it is possible to detect the azimuth with the highest possible accuracy even when the relative speed is low. From the perspective of doing
According to a fourth aspect of the present invention, in the vehicle surroundings monitoring device, the first arithmetic means includes a relative distance between the object and the vehicle based on a detection signal from a first radar sensor. Along with calculating the relative speed of the object with respect to the vehicle as information depending on the relative position of the object, the second calculating means also calculates the distance between the object and the vehicle based on a detection signal from the second radar sensor. The relative distance and the relative speed of the object relative to the vehicle are calculated as information depending on the relative position of the object, and the azimuth calculating means calculates the relative distance of each relative distance calculated by the first and second calculating means. Relative distance ratio calculating means for calculating the ratio, relative speed ratio calculating means for calculating the ratio of the relative speeds calculated by the first and second calculating means, and relative distance ratio calculating means. Each relative Relative distance corresponding direction calculating means for calculating the direction of the object from the vehicle based on the separation ratio; and the direction of the object from the vehicle based on the ratio of each relative speed calculated by the relative speed ratio calculating means. And a relative speed corresponding direction calculating means for calculating the relative speed of the object calculated based on the detection signal from the first radar sensor or the detection signal from the second radar sensor is smaller than a predetermined value. And the direction calculated by the relative distance corresponding direction calculating means when the speed determining means determines that the relative speed of the object is smaller than a predetermined value. When the speed determining means determines that the relative speed of the object is not smaller than a predetermined value, the azimuth calculated by the relative speed corresponding azimuth calculating means is used as the azimuth calculating means. It can be configured with a selection means for selecting as the output information.

In such a vehicle periphery monitoring apparatus, when the relative speed of the object calculated based on the detection signal from the first radar sensor or the detection signal from the second radar sensor is larger than a predetermined value, The azimuth of the object from the vehicle is calculated based on the ratio of the relative speeds calculated based on the detection signals from the first and second radar sensors. When the relative speed of the object is smaller than the predetermined value, the azimuth of the object from the vehicle is calculated based on the ratio of the relative distances calculated based on the detection signals from the first and second radar sensors. Is done.

When the relative speed of the object with respect to the vehicle is smaller than a predetermined value, the relative distance calculated based on the detection signals from the first and second radar sensors is used without using the relative speed ratio. Since the azimuth is calculated based on the ratio, it is possible to prevent the accuracy of azimuth detection from deteriorating due to a decrease in relative speed. Further, from the viewpoint that a driver can know information on whether or not an object is present in a lane adjacent to the lane in which the vehicle travels, the present invention provides the above-described each of the above-described aspects. In the vehicle periphery monitoring device, a curvature estimating means for estimating and calculating a curvature of a road on which the vehicle travels, and a relative distance between an object calculated based on at least one of the first radar sensor and the second radar sensor. Based on the azimuth of the object calculated from the vehicle by the azimuth calculating means and the curvature of the road estimated by the curvature estimating means, the object is present in a lane adjacent to the lane in which the vehicle runs. It may be configured to have a vehicle adjacent lane determining means for determining whether or not the vehicle is in the lane.

[0013] In such a vehicle periphery monitoring device, the object is determined based on the azimuth of the object from the vehicle, the relative distance of the object from the vehicle, the curvature of the road, and the lane structure of the road. It is determined whether the vehicle is in a lane adjacent to the lane in which the vehicle travels. If the determination result is provided to the driver, the burden on the driver performing the driving operation when changing lanes can be reduced.

The curvature estimating means for estimating and calculating the curvature of the road may be one that obtains the curvature from the map information of the road, or one that calculates the curvature from the steering angle, the yaw rate, or the vehicle speed and the lateral G of the vehicle. Is also good. In addition, from the viewpoint that it is possible to provide a driver with information as to whether or not an object moving in an adjacent lane is near the vehicle, the present invention provides the above-described vehicle periphery monitoring device as described in claim 6. When the vehicle adjacent lane determining means determines that the object is present in the lane adjacent to the lane in which the vehicle travels, at least one of the detection signals from the first radar sensor and the second radar sensor Distance determining means for determining whether the relative distance to the object calculated based on the distance is smaller than a predetermined value; and May include parallel running information generating means for generating parallel running information indicating that the vehicle moves near the vehicle in an adjacent lane.

In such a vehicle periphery monitoring device, if the parallel running information is provided to the driver, the driver can know that an object moving in the adjacent lane exists near the vehicle. it can. From the viewpoint that the driver can be informed to the driver that an object moving in the adjacent lane is rapidly approaching the vehicle, the present invention provides a vehicle periphery monitoring device as described in claim 7. In the above, when the vehicle adjacent lane determining means determines that the object is present in the lane adjacent to the lane in which the vehicle travels, at least one of the detection signals from the first radar sensor and the second radar sensor Approach information calculating means for calculating information indicating the degree of speed of an object moving in the adjacent lane based on the information, and whether the information calculated by the approach information calculating means indicates a speed greater than a predetermined speed An approach speed determining means for determining whether the information indicates a speed greater than a predetermined speed, and an object contacting means for generating object approach information indicating that when the approach speed determining means determines that the information indicates a speed greater than a predetermined speed. It can be configured to have an information generation unit.

In such a vehicle periphery monitoring device, if the object approach information is provided to the driver, the driver can know the presence of an object approaching the vehicle in an adjacent lane at a relatively high speed. Can be. From the viewpoint that the lane change of the vehicle can be prevented beforehand when an object is moving in the adjacent lane, the present invention provides a vehicle periphery monitoring device according to the present invention, in which the driver A lane change intention determining means for determining whether or not there is an intention to change; and a lane change intention determining means for determining that the driver has an intention to change lanes. Determining means for determining whether or not parallel running information indicating that an object moves in the vicinity of the vehicle has been generated by the parallel running information generating means; and determining that the parallel running information has been generated. Sometimes, it can be configured to include alarm output means for outputting alarm information to the driver.

In such a vehicle periphery monitoring device, when it is determined that the driver has an intention to change lanes, when parallel running information is generated, warning information is output from the warning output means. The driver can use the warning information to know the presence of an object moving in the vicinity of the vehicle in the adjacent lane. Therefore, the driver can interrupt the driving operation for changing lanes based on the alarm information.

The lane change intention determining means is not particularly limited as long as it can detect the driver's intention to change lanes. For example, one that determines intention based on the operation direction of the direction indicator, one that determines intention based on the operation direction of the steering wheel, one that determines intention based on the operation pattern of the steering wheel, or a lane change Any device that determines the intention based on the operation of the dedicated switch operated when performing the operation can be used as the lane change intention determining means.

From a similar viewpoint, according to the present invention, in the vehicle periphery monitoring device, the lane change intention determination for judging whether or not the driver has a lane change intention is provided. Means, and when the lane change intention determining means determines that the driver intends to change lanes, the object is moving at a speed higher than a predetermined speed in an adjacent lane to be changed by the driver. Determination means for determining whether or not the object approach information representing the object proximity information is generated by the object approach information generation means; and when the determination means determines that the object proximity information has been generated, alert information is issued to the driver. And an alarm output unit for outputting.

In such a vehicle periphery monitoring device, when it is determined that the driver has an intention to change lanes, when object approach information is generated, alarm information is output from the alarm output means. The driver can use the warning information to know the presence of an object approaching the vehicle at an adjacent lane at a relatively high speed. Therefore, the driver can interrupt the driving operation for changing lanes based on the alarm information.

Furthermore, in order to solve the above-mentioned problem, the present invention provides a radar apparatus for detecting a distance from an object by using a radar sensor for detecting a distance from the object. In a vehicle periphery monitoring device configured to detect a relationship, a first radar sensor installed at a rear part of the vehicle and forming a first monitoring area on a rear side of the vehicle, A second radar sensor that is installed at a different position from the first radar sensor and forms a second monitoring area overlapping the first monitoring area, based on a detection signal from the first radar sensor. First calculating means for calculating information depending on the relative position between the object in the first monitoring area and the vehicle, and a second calculating area based on a detection signal from the second radar sensor. Object and the vehicle Calculating means for calculating information dependent on the relative position of the vehicle, and information dependent on the relative position of the object and the vehicle calculated by the first calculating means and the second calculating means. When there are a plurality of, respectively, while calculating the first change information depending on the change in the relative speed of the object based on each information obtained by the first calculating means,
Change information calculation means for calculating second change information depending on a change in the relative speed of the object based on each information obtained by the second calculation means; and the first change information and the second change which are closer to each other. In order from the pair of information, each piece of information dependent on the relative position between the object and the vehicle calculated by the first calculation means and the second calculation means corresponding to the pair is assumed to be for the same object. And allocating means for allocating.

The case where there are a plurality of pieces of information depending on the relative positions of the object and the vehicle, which are calculated based on the detection signals from the first radar sensor and the second radar sensor, respectively, is the same as the case where This is a case where a plurality of objects exist in one monitoring area and the second monitoring area. In such a case, first change information depending on a change in the relative speed of each object is obtained based on a detection signal corresponding to each object from the first radar sensor, and each change information from the second radar sensor is obtained. Based on the detection signal corresponding to the object, second change information depending on a change in the relative speed of each object is obtained. The first change information and the second change information for the same object are relatively close values because they only differ due to the difference in the installation positions of the first radar sensor and the second radar sensor.

Accordingly, from the plurality of the first change information and the second change information obtained, a plurality of the first change information and the second change information are calculated in order from the closest pair by the first calculation means and the second calculation means corresponding to the pair. Each piece of information depending on the relative position between the object and the vehicle is assigned to the same object.
By such a vehicle periphery monitoring device, even if a plurality of objects exist in the overlapping first and second monitoring areas, each detection signal from the first radar sensor and the second radar sensor for each object. The information calculated based on the relative position between the object and the vehicle can be accurately allocated.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. A vehicle equipped with a vehicle periphery monitoring device according to one embodiment of the present invention is provided with, for example, a radar sensor (for example, a laser radar) as shown in FIG.

In FIG. 1, four radar sensors are installed on a rear bumper of a vehicle 100. That is, the right outside radar sensor (RRO) 1 is provided at the right corner of the rear bumper.
2 and a right inner radar sensor (RRI) 14 are installed, and a left outer radar sensor (RLO) 16 and a left inner radar sensor (RLI) 18 are provided at the left corner of the rear bumper.
Is installed.

As shown in FIG. 2, a monitoring area ERO by the right outside radar sensor (RRO) 12 and a monitoring area ELI by the inside left radar sensor (RLI) 18 are formed on the right rear side of the vehicle 100. These monitoring areas ERO
And ELI have overlapping regions. This overlapping area is the right rear side monitoring area. That is, in the right rear side monitoring area, an object (other vehicle) is monitored by the two radar sensors 12 and 18 installed at both corners at the rear of the vehicle 100.

As shown in FIG. 3, a monitoring area ELO by the outside left radar sensor (RLO) 16 and a monitoring area ERI by the inside right radar sensor (RRI) 14 are formed on the left rear side of the vehicle 100. I have. These monitoring areas ELO and ERI also have overlapping areas. This overlapping area is the left rear side monitoring area. The vehicle periphery monitoring device is configured, for example, as shown in FIG.

In FIG. 4, the detection signals from the radar sensors 12, 14, 16, and 18 are selected by the multiplexer 20 in order to select the above-described detection areas, and the selected detection signals are A / D converted. The data is converted into digital data by the device 22 and supplied to the control unit 30. Further, respective detection signals from the direction indicator sensor 24, the steering sensor 26, and the vehicle speed sensor 28 are also supplied to the control unit 30.

The control unit 30 controls each radar sensor 1
Detection data and direction indicator sensor 24 based on detection signals from 2, 14, 16, and 18, steering sensor 2
A monitoring process, which will be described later, is performed based on each detection signal from the vehicle speed sensor 6 and the vehicle speed sensor 28. Then, an alarm control signal corresponding to the monitoring result is supplied from the control unit 30 to the alarm output device 40.

While the vehicle 100 equipped with the above-described vehicle periphery monitoring device is running, the control unit 30 performs a monitoring process according to the procedure shown in FIG. First, a distance to an object (following vehicle) in the right rear side monitoring area and the left rear side monitoring area is calculated based on a detection signal from each radar sensor (S1). Each radar sensor 12, 14,
16 and 18 are pulse waves (
For example, when a following vehicle exists in the monitoring area, a reflected pulse from the following vehicle is received. Then, a detection signal corresponding to the received reflected pulse is transmitted to each of the radar sensors 12, 14, 16, and 18.
Output from The control unit 30 calculates the distance to the following vehicle in the monitoring area based on the difference between the output timing of the pulse wave from each of the radar sensors 12, 14, 16, and 18 and the reception timing of the reflected pulse.

More specifically, a right detection distance Rr is calculated based on a detection signal from the outside right radar sensor 12 for a following vehicle existing in the right rear side monitoring area (monitoring areas ERO and ELI). At the same time, a left detection distance Rl is calculated based on a detection signal from the left inner radar sensor 18.
Also, the left rear side monitoring area (monitoring area ELO and ERI)
The left outside radar sensor 16
The left detection distance Rl is calculated on the basis of the detection signal from the right, and the right detection distance Rr is calculated based on the detection signal from the right inner radar sensor 14.

When no object (following vehicle) exists in the monitoring area, the reflected wave corresponding to the transmitted pulse wave is not received, so that the distance is not calculated. When the distance to the following vehicle in each monitoring area is calculated as described above, the vehicle 1 of the following vehicle is calculated based on the change in the distance.
The relative speed with respect to 00 is calculated (S2). That is, the right detection relative speed Vr is calculated based on the change in the right detection distance Rr calculated for the following vehicle in the right rear side monitoring area or the left rear side monitoring area, and the left detection distance Rr is calculated.
The left detected relative speed Vl is calculated based on the change in l.

Thus, for one succeeding vehicle in each monitoring area, the right detection information of the right detection distance Rr and the right detection relative speed Vr, and the left detection information of the left detection distance Rl and the left detection relative speed Vl are calculated. Is obtained. As described above, when the distance to the succeeding area and the relative speed in each monitoring area are calculated based on the detection signal from each radar sensor, a pairing process is executed (S3).

When a plurality of following vehicles exist in the monitoring area, a plurality of reflected waves corresponding to each following vehicle are received for one pulse wave transmitted from the radar sensor. And, corresponding to the plurality of reflected waves received,
A plurality of right detection information (right detection distance Rr, right detection relative speed Vr) and a plurality of left detection information (left detection distance Rl, left detection relative speed Vl) are obtained. Therefore, it is necessary to associate the right detection information and the left detection information for each succeeding vehicle. The process for associating the right side detection information with the left side detection information is the pairing process.

For example, as shown in FIG. 6, behind a vehicle 100 mounted with the vehicle periphery monitoring device traveling on the lane L0, a following vehicle 200 traveling on the lane L1 adjacent to the lane L0, and further on the lane L1. When there is a following vehicle 300 traveling in the adjacent lane L2, the right outside radar sensor 1
The distances to the following vehicles 200 and 300 calculated based on the second detection signal may be equal. In such a case, as shown in FIG. 7, when a pulse wave is transmitted at a certain time (t = t0), the inner left radar sensor 18 receives two reflected pulses corresponding to each of the following vehicles 200 and 300. (Reception _{Lt = t1} ) is the right outside radar sensor 12.
Is such that two reflected pulses corresponding to the following vehicles 200 and 300 overlap each other, and apparently one reflected pulse is received (reception R _{t = t1} ).

Further, when the relative positional relationship between the vehicle 100 and each of the following vehicles 200 and 300 changes after a lapse of time, the right outer radar sensor 12 and the left inner radar sensor respond to one transmitted pulse wave. 18 at each of the following vehicles 2
Two reflected pulses corresponding to 00 and 300 are received.
In this way, the vehicle 100 and each of the following vehicles 200, 30
Depending on the relative positional relationship with 0, the number of reflected pulses received by the right radar sensor and the number of reflected pulses received by the left radar sensor may differ. In such a situation where the state of the detection signal output from each radar sensor changes, the correspondence between the right detection information (distance, relative speed) and the left detection information (distance, relative speed) calculated based on each detection signal. It is generally difficult to attach (pairing processing).

In this vehicle periphery monitoring device, a pairing process is performed as follows. For example, as shown in FIG.
A relatively close position in the lateral direction from the vehicle 100 (for example,
When the distance from the vehicle 200 traveling on the adjacent lane) at the constant speed V0 changes from R1 to R2, the relative speed calculated at that time changes from V11 to V12. The vehicle 300 traveling at a relatively distant position in the lateral direction from the vehicle 100 (for example, a lane further adjacent to an adjacent lane) at a constant speed V0.
And the distance from R1 to R2
, The relative speed calculated at that time is V2
It changes from 1 to V22. Each subsequent vehicle 200, 300
Is different in the lateral position with respect to the vehicle 100, so that the state of the change in the relative speed calculated from the change in the detected distance is different. That is, the rate of change of the relative speed corresponds to the lateral position of each succeeding vehicle with respect to the vehicle 100.

For example, the rate of change of the relative speed 検 出 1 when the detected distance to the following vehicle 200 changes from R1 to R2.
Δ1 = (V12−V11) / V11 The rate of change Δ2 in relative speed when the detection distance to the following vehicle 300 changes from R1 to R2 is Δ2 = (V22−V21) / V21.

Vehicle 2 traveling in adjacent lane at constant speed V0
FIG. 9 shows a simulation result of the change rate Δ1 of the relative speed of 00 and the change rate Δ2 of the relative speed of the vehicle 300 traveling at a constant speed V0 in the lane further adjacent to the adjacent lane. The simulation result shown in FIG. 9 is based on the following vehicle 20 traveling in the right rear side monitoring area of the vehicle 100.
0 and 300 (see FIG. 6).

In FIG. 9, the right outside radar sensor 12
The rate of change of the relative speed of the vehicle 200 calculated based on the detection signal from the (right sensor) changes like the characteristic Q1R, and is calculated based on the detection signal from the left inner radar sensor 18 (left sensor). The change rate of the relative speed of the vehicle 200 changes like the characteristic Q1L. Further, the rate of change of the relative speed of the vehicle 300 calculated based on the detection signal from the right sensor changes like the characteristic Q2R, and the change in the relative speed of the vehicle 300 calculated based on the detection signal from the left sensor. The rate changes like the characteristic Q2L. The rate of change of each relative speed is based on the relative speed at a detection distance R of 40 meters (R1 = 40 m).

The characteristic Q3 represents a change in the distance Rr detected by the right sensor of the vehicle 200. The vehicle 3
The detection distance Rl of the left sensor at 00 also changes substantially in the same manner as the characteristic Q3 up to about 20 mails. From the qualitative analysis (see FIG. 8) of the change rate of the relative speed and the lateral position of the following vehicle as described above, and the simulation result as shown in FIG. 9, the closer right sensor obtained at a certain detection distance is used. And the change rate of the relative speed calculated based on the detection signal of the left sensor and the change rate of the relative speed calculated based on the detection signal of the left sensor are assigned to the same following vehicle. That is, the following vehicle having the same right detection information (right detection distance and right detection relative speed) and left detection information (left detection distance and left detection relative speed) as the basis for calculating such a rate of change in relative speed. (Pairing).

In the example shown in FIG. 9, when the detection distance Rr of the right sensor is 35 meters (Rr = 35 m), the relative speed change rate Δ1R (35 m) calculated based on the detection signal of the right sensor and the left sensor The change rate Δ1L (35 m) of the relative speed calculated based on the detection signal from the sensor is assigned as that of the same following vehicle. Also, the following vehicle has the same relative speed change rate Δ2R (35 m) calculated based on the detection signal from the right sensor and the same relative speed change rate Δ2L (35 m) calculated based on the detection signal from the left sensor. Assigned as That is, the relative speed change rate Δ1R (35m) calculated based on the detection signal from the right sensor and the relative speed change rate Δ2L (35) calculated based on the detection signal from the left sensor are the same. It is not assigned as a following vehicle.

As described above, when the right detection information (right detection distance and right detection relative speed) and the left detection information (left detection distance and left detection relative speed) can be associated (paired), Using the attached right detection information and left detection information, a traveling lane determination process (S4), a parallel running vehicle determination process (S5), a close obstacle process (S6), and an alarm output process (S7) are executed. (See FIG. 5).

The traveling lane discrimination processing is executed, for example, according to the procedure shown in FIG. In FIG. 10, the right detected relative speed Vr (or the left detected relative speed Vl) is a predetermined value Vmi.
It is determined whether it is greater than n (S401). If the right detected relative speed Vr (or the left detected relative speed Vl) is larger than the predetermined value Vmin, a ratio (detected speed ratio) α between the right detected relative speed Vr and the left detected relative speed Vl is calculated (S
402).

Α = Vr / Vl The azimuth θf of the following vehicle is calculated based on the detected speed ratio a (S403). As shown in FIG.
The ratio (Vr1) between the right detected relative speed Vr1 and the left detected relative speed Vl1 of the following vehicle 150 traveling in the same lane as the vehicle 100
/ Vl1) is almost 1. And each subsequent vehicle 15
If the azimuth angles of the vehicles 100, 0, 200, and 300 are different, the detection speed ratios Vr1 / Vl1, Vr2 / Vl2, and Vr1 / Vl1, Vr2 / Vl2 for the following vehicles 150, 200, and 300 traveling at the detection distance R at a constant speed V0. Vr3 / Vl3 is also different. That is, the azimuth of the following vehicle from the vehicle 100 depends on the detected speed ratio α. Therefore, the azimuth of the following vehicle from the vehicle 100 can be calculated based on the detected speed ratio α.

For example, as a result of the simulation, FIG.
The relationship between the detection speed ratio α and the azimuth θf when the detection distance Rr of the right sensor is 30 meters as shown in FIG. Similarly, as shown in FIG.
The relationship at 0 meters (Rr = 10 m) is characteristic Q1, the relationship at a detection distance of 20 meters (Rr = 20m) is characteristic Q2,
A relationship at a detection distance of 35 meters (Rr = 35 m) is obtained as a characteristic Q4, and a relationship at a detection distance of 40 meters (Rr = 40 m) is obtained as a characteristic Q5. In FIG. 13, the characteristic Q3 indicates that the detection distance is 30 meters (Rr = 30
m) shows the relationship between the detected speed ratio α and the azimuth angle θf.

A table describing the relationship between the detected speed ratio α and the azimuth θf as shown in FIG. 13 (FIG. 12) is stored in advance in a memory (for example, ROM) in the control unit 30. Then, as described above, the ratio between the right detected relative speed Vr and the left detected relative speed V1 of the following vehicle (detected speed ratio).
After α is calculated (S402), the table corresponding to each detection distance stored in the memory as described above (FIG. 13)
Azimuth θf corresponding to the detected speed ratio α
Is read from the memory (S403).

On the other hand, when the right detection relative speed Vr or the left detection relative speed Vl is equal to or less than the predetermined value Vmin, the azimuth angle θf is obtained from the ratio of each detection speed in the detection method having a coarse speed resolution.
Is expected to be difficult to recognize, the ratio (detection distance ratio) α between the right detection distance Rr and the left detection distance Rl
Is calculated (S415), and the azimuth θf of the following vehicle with respect to the vehicle 100 is calculated from the detected distance ratio α (S4).
16). The detection distance ratio α (= Rr / Rl) and the azimuth angle θ
The relationship with f is the same as the relationship between the detected speed ratio α (Vr / Vl) and the azimuth angle θf (see FIGS. 12 and 13), and the azimuth angle θf is obtained from the same table.

When the azimuth θf of the following vehicle detected with respect to the vehicle 100 detected as described above is obtained, the curve radius of the traveling locus (traveling lane) of the vehicle 100 and the direction of the curve (right curve or left curve) are obtained. Curve) is estimated (S404). This estimation calculation includes detection information from the steering sensor 26 and the yaw rate sensor (not shown) and a lateral G sensor (using a strain gauge:
(Not shown) and detection information from the vehicle speed sensor 28 and the like.

Next, it is determined whether or not the curve direction obtained by the above estimation is a right curve (S40).
5). Here, if it is determined that the vehicle is a right curve, for example, the right adjacent lane determination threshold (θrri, θrro) and the left corresponding to the curve radius estimated and calculated from the determination threshold map for the right curve as shown in FIG. An adjacent lane determination threshold (θrli, θrlo) is obtained (S406). This judgment threshold map is
It is stored in the memory of the control unit 30 in advance.

As shown in FIG. 15, the inside point and the outside point of the lane adjacent to the right lane of the lane in which the vehicle 100 travels at the same distance as the detection distance Rc to the following vehicle 200 are determined by the vehicle 100
The angle approaching from the right is the lane judgment judgment threshold (θ
rri, θrro), and the angles at which the inside point and the outside point of the left adjacent lane of the lane in which the vehicle 100 travels face the vehicle 100 are the left adjacent lane determination thresholds (θrli, θrl).
o). The determination curve map for the right curve shows the right adjacent lane determination threshold (θrri, θrro) and the left adjacent lane determination threshold (θrli, θrlo) corresponding to each curve radius on the right curve road. In FIG. 14, the relationship between the curve radius and the right adjacent lane determination threshold θrro (corresponding to the outside point) is the characteristic Q1.
The relationship with the right adjacent lane determination threshold θrri (corresponding to the inside point) is the characteristic Q2. The relationship between the curve radius and the left adjacent lane determination threshold θrli (corresponding to the inside point) is characteristic Q3, and the relationship between the curve radius and the left adjacent lane determination threshold θrlo (corresponding to the outside point) is characteristic Q4.

For example, a curve radius of 100 meters (R =
100 m) and a detection distance of 30 meters (Rc = 30 m), as shown in FIG. 15, the left adjacent lane judgment thresholds (θrli, θrlo) are (5.2 deg, -1.68).
deg), and the right adjacent lane judgment threshold (θrri
, Θrro) is (18.49deg, 11.97deg)
Becomes

If the detected azimuth angle θf with respect to the following vehicle 200 is within the range of the right adjacent determination threshold (θrri, θrro), it can be determined that the following vehicle 200 exists in the right adjacent lane. If the detected azimuth is within the range of the left determination threshold (θrli, θrlo), it can be determined that the following vehicle 200 is present in the left adjacent lane.

The judgment threshold map differs depending on the detection distance. For example, a judgment threshold map created for each of a plurality of detection distances is stored in the memory of the control unit 30. Each time the detection distance is obtained, the right adjacent lane determination threshold (θrr
i, θrro) and the left adjacent determination threshold (θrli,
θrlo).

The detection distance used in this processing is:
Whether it is calculated based on the detection signal from the right radar sensor or calculated based on the detection signal from the left radar sensor, furthermore, based on the detection signals from both radar sensors, for example, triangulation May be obtained by the above method. In order to obtain the above-described determination threshold map, the right (left) adjacent lane determination threshold corresponding to the detection distance Rc of the following vehicle 200 is calculated as follows.

When the curve radius R, the lane width Wr, and the distance W between the right radar sensor and the left radar sensor are set as shown in FIG. 15, the arc of the detection distance Rc with the origin at the center of the curve radius is as shown in FIG.

[0057]

(Equation 1)

And the outer boundary of the left and right adjacent lanes is

[0059]

(Equation 2)

The inner boundary between the left and right adjacent lanes is

[0061]

(Equation 3)

Is obtained. The intersection (xi, yi) between the arc of the radius Rc and the inner boundary line is

[0063]

(Equation 4)

[0064]

(Equation 5)

Where the intersection (xo, yo) between the arc and the outer boundary is

[0066]

(Equation 6)

[0067]

(Equation 7)

Is obtained. As a result, the azimuth θr * i (*) of the intersection (xi, yi) viewed from the rear center of the vehicle 100
Is r or l) is

[0069]

(Equation 8)

And the azimuth θr * o (* is r or l) of the intersection (xo, yo) as viewed from the rear center of the vehicle 100.
)

[0071]

(Equation 9)

Is obtained. These azimuth angles θrri, θril, θrr
o and θrlo are adjacent lane judgment thresholds. As described above, when the right adjacent lane determination threshold (θrri, θrro) and the left adjacent lane determination threshold (θrli, θrlo) corresponding to the detected distance and the curve radius are obtained (S406), the following vehicle 200 is shifted to the right adjacent lane. Is determined (S407). This determination is performed when the azimuth angle θf of the following vehicle 200 obtained in step S403 is equal to the right adjacent lane threshold (θrri, θrro).
(Θrro <θ
f <θrri).

Here, when it is determined that the following vehicle 200 exists in the right adjacent lane, the right adjacent lane determination flag (F_R)
rightlane) is set to “1” (S41)
3). On the other hand, when it is determined that the following vehicle 200 does not exist in the right adjacent lane, it is further determined whether the following vehicle 200 exists in the left adjacent lane (S408). This judgment is
Azimuth angle θ of following vehicle 200 obtained in step S403
It is determined whether or not f is within the range of the left adjacent lane threshold (θrli, θrlo) (θrlo <θf <
θrli). Here, when it is determined that the following vehicle 200 exists in the left adjacent lane, the left adjacent lane determination determination flag (F_
LeftLane) is set to “1” (S40)
9).

On the other hand, if it is determined that the following vehicle 200 does not exist in the left adjacent lane, the right adjacent lane determination flag and the left adjacent lane determination flag are cleared to "0" (S41).
0). Steps S406 to S410 described above
The processing in step S413 is processing when it is determined that the traveling locus (traveling lane) of the vehicle 100 is a right curve. On the other hand, if it is determined in step S405 that the traveling locus (traveling lane) of the vehicle 100 is not a right curve (a left curve), the process is executed according to the same procedure as described above.

That is, from the left curve judgment threshold map corresponding to the detection distance of the following vehicle 200, the right adjacent lane judgment thresholds (θlri, θlro) corresponding to the curve radius estimated and calculated in step S404 and the left adjacent lane. The determination threshold (θlli, θllo) is obtained (S411). As shown in FIG. 16, for example, the left-curve determination threshold map for the left curve is a right-adjacent lane determination threshold (θlri, θlro) and a left-adjacent lane determination threshold (θlli, θllo) corresponding to each curve radius on the left curve road. Is shown.

In FIG. 16, the relationship between the curve radius and the right adjacent lane determination threshold θlro (corresponding to the outer boundary line) is a characteristic Q1, and the right adjacent lane determination threshold θ
The relationship with lri (corresponding to the inner boundary) is characteristic Q2.
The curve radius and the left adjacent lane judgment threshold θll
The relationship with i (corresponding to the inside boundary) is characteristic Q3, and the relationship with the left adjacent lane determination threshold θllo (corresponding to the outside boundary) is characteristic Q4.

In order to obtain the left-curve judgment threshold map, the right (left) adjacent lane judgment threshold corresponding to the detection distance Rc of the following vehicle 200 is calculated in the same manner as the right curve judgment threshold map. It is calculated as follows. Assuming the curve radius R, the lane width Wr, and the distance W between the right radar sensor and the left radar sensor, as shown in FIG. 17, the arc of the detection distance Rc with the origin at the center of the curve radius is:

[0078]

(Equation 10)

And the outer boundary of the left and right adjacent lanes is

[0080]

[Equation 11]

The boundary line inside the adjacent lanes on the left and right is

[0082]

(Equation 12)

Is obtained. The intersection (xi, yi) between the arc of the radius Rc and the inner boundary line is

[0084]

(Equation 13)

[0085]

[Equation 14]

The intersection (xo, yo) between the arc and the outer boundary line is:

[0087]

(Equation 15)

[0088]

(Equation 16)

## EQU11 ## As a result, the azimuth θl * i (*) of the intersection (xi, yi) viewed from the rear center of the vehicle 100
Is r or l) is

[0090]

[Equation 17]

[0091] The azimuth θl * o (* is r or
l) is

[0092]

(Equation 18)

Is obtained. These azimuths θlli, θlri, θll
o and θlro are the adjacent lane determination thresholds. In FIG. 17, when the estimated curve radius is 100 meters (R = 100 m) and the detection distance of the following vehicle 200 is 30 meters (Rc = 30 m), the right adjacent lane determination thresholds (θlri, θlro) are ( 5.2deg,
−1.68 deg).

As described above, on the left curve road,
When the right adjacent lane determination threshold (θlri, θlro) and the left adjacent lane determination threshold (θlli, θllo) corresponding to the detected distance and the curve radius are obtained (S41).
1) It is determined whether the following vehicle 200 exists in the right adjacent lane (S412). This determination is based on the following vehicle 2
The azimuth θf of 00 is the right adjacent lane determination threshold (θ
lri, θlro) is determined (θlro <θf <θlri).

Here, when it is determined that the following vehicle 200 exists in the right adjacent lane, the right adjacent lane determination flag (F_R)
rightlane) is set to “1” (S41)
3). On the other hand, when it is determined that the following vehicle 200 does not exist in the right adjacent lane, it is further determined whether the following vehicle 200 exists in the left adjacent lane (S414). This judgment is
It is determined whether or not the azimuth θf of the following vehicle 200 is within the range of the left adjacent lane determination threshold (θlli, θllo) (θllo <θf <θlli). Here, when it is determined that the following vehicle 200 exists in the left adjacent lane, the left adjacent lane determination determination flag (F_LeftLane) is set to “1” (S409).

When the traveling lane discriminating process (step S5 in FIG. 5) is completed according to the above procedure, a parallel running vehicle discriminating process (step S6 in FIG. 5) is executed. The parallel running vehicle determination process is a process for determining whether or not there is another vehicle traveling in an adjacent lane within a predetermined distance from the vehicle 100 in the adjacent lane. For example, the parallel vehicle determination process is performed according to the procedure shown in FIG. You.

In FIG. 18, first, a right lane parallel running flag (F_RightLaneH) as described later is set (S501), and a left lane parallel running flag (F_leftLaneH) is set (S501). Each determination of S502) is performed. When neither the right lane parallel running flag (F_Right Lane H) nor the left lane parallel running flag (F_Left Lane H) is set, it is further determined whether or not the above-described right adjacent lane determination flag (F_Right Lane) is set. Is determined.

Here, the right adjacent lane discrimination flag (F_Ri)
If (ghtLane) is set to “1”, it is further determined whether or not the detection distance Rr calculated based on the detection signal from the right radar sensor is smaller than a predetermined distance Rgap (for example, several meters). (S511). That is, the succeeding vehicle 200 is positioned a predetermined distance R behind the vehicle 100.
It is determined whether the vehicle has approached the gap.

If it is determined that the detected distance Rr is smaller than the predetermined distance Rgap, it is determined that the following vehicle 200 is already in a parallel running state, and the parallel running scheduled time Tpr is calculated (S51).
2). The scheduled parallel running time Tpr is calculated according to Tpr = Rr / Vr (10 m). Here, Vr (10 m) is a relative speed at a point where the detection distance Rr is 10 meters (Rr = 10 m).

Further, when the calculated parallel running time Tpr thus calculated is calculated, it is determined whether the parallel running scheduled time Tpr is longer than a predetermined time Tpmin (S513). The predetermined time Tpmin is determined based on the minimum time from when the driver recognizes the presence of a vehicle running in the adjacent lane until the driver reacts. If the scheduled parallel running time Tpr is longer than the predetermined time, the right lane parallel running timer (TPR) is set to Tpr (S514), and the right lane parallel running flag (F_RightLaneH) is set to "1". (S515).

Note that the right adjacent lane discrimination flag (F_Rig)
If the detected distance Rr is equal to or greater than the predetermined distance Rgap in a state where htLane) is set, it is determined that the following vehicle 200 traveling on the right adjacent lane is not yet in the parallel running state, and the above-described right lane traveling timer is set. (S51
4) and right lane parallel running flag (F_Right Lane)
H) is not set to "1" (S515). If the scheduled parallel running time Tpr is shorter than a predetermined time Tpmin (corresponding to the minimum time from when the driver recognizes the presence of a vehicle running in the adjacent lane to when the vehicle reacts), an alarm is issued. Similarly, it is determined that the driver cannot respond, and similarly, a right lane running timer is set (S514) and a right lane parallel running flag (F_RightLaneH) is set (S515).
Is not set.

The right adjacent lane discrimination flag (F
_RightLane is not set (S
NO at 510), and a left adjacent lane discrimination flag (F_L)
It is determined whether or not (leftLane) is set (S520). Here, the following vehicle 200 is located in the left adjacent lane.
Is running, the left adjacent lane determination flag (F
When _LeftLane is set, similarly to the case where the right adjacent lane flag (F_RightLane) is set, it is determined whether the detection distance Rl calculated based on the detection signal from the left radar sensor is smaller than a predetermined value Rgap. It is determined (S521). If the detected distance Rl is smaller than the predetermined value Rgap, that is, if it is determined that there is a following vehicle running in the left adjacent lane,
Further, the calculation of the estimated parallel running time Tpl (= Rl / Vl (10 m)) (S522) and the determination of whether the estimated parallel running time Tpl is longer than the predetermined time Tpmin determined based on the minimum reaction time of the driver. (S523) is performed.

If the scheduled parallel running time Tpl is longer than the predetermined time Tpmin, the left lane parallel running timer TPL
Is set to Tpl (TPL = Tpl) (S52).
4) Left lane parallel running flag (F_LeftLaneH)
Is set to "1" (S525). In the processing for the left adjacent lane, the detection distance R of the following vehicle is also used.
When l is equal to or more than a predetermined value (NO in S521), when parallel running scheduled time Tpl is equal to or less than predetermined time Tpmin (N in S523).
O), the setting of the left lane parallel running timer and the setting of the left lane parallel running flag (F_LeftLaneH) to “1” are not performed.

The right lane parallel running timer TPR set to the scheduled parallel running time Tpr as described above is sequentially counted down, and it is determined whether or not the timer TPR has timed out (TPR = 0) (S530). Then, the left parallel running timer TPL set to the parallel running scheduled time Tpl as described above is sequentially counted down, and it is determined whether or not the timer TPL is timed up (TPL = 0) (S530, S531). In a state where neither timer TPR nor TPL has timed out, it is determined whether the right lane parallel running flag (F_RightLaneH) is set to “1” (S501).
Then, it is determined whether the left lane parallel running flag (F_LeftLaneH) is set to “1” (S502). Right lane parallel running flag (F_Right Lan)
eH) and the left lane parallel running flag (F_LeftLane)
If any of H) is set to “1”, it is repeatedly determined whether or not the timers TPR and TPL have timed out (S501, S502, S53).
0, S 531).

When the timer TPR or TPL times out in the course of the processing repeatedly performed as described above (elapsed parallel running time: TPR = 0 or TPL = 0),
Corresponding right lane running flag (F_Right Lane)
H) or left lane parallel running flag (F_LeftLan)
eH) is reset to “0” (S532, S53)
3).

Parallel running vehicle discrimination processing as described above (S5)
The following approach obstacle discrimination processing (S6) is performed, for example, in FIG.
This is performed according to the procedure shown in In FIG. 19, it is determined whether or not a following vehicle exists in the right adjacent lane (S60).
1). This determination is based on the right adjacent lane flag (F_R
rightlane) is set to "1".

Here, when it is determined that a following vehicle exists in the right adjacent lane, the headway time Thr between the vehicle 100 and the following vehicle 200 is calculated based on the detection distance Rr and the detection distance Rr calculated based on the detection signal from the right radar sensor. , Its detection distance
It is calculated according to the following equation based on the relative speed Vr calculated from Rr (S602). Thr = Rr / Vr The calculated headway time Thr is equal to a predetermined time Th.
It is determined whether it is greater than min (S603). When the headway time Thr is shorter than the predetermined time Thmin (S
(NO in 603), the right adjacent lane approaching vehicle flag (F_Right LanCar) is set to “1”, assuming that there is a following vehicle that quickly approaches the host vehicle 100 in the right adjacent lane (S604).

On the other hand, the headway time Thr is equal to the predetermined time Th.
If it is larger than min (YES in S603), it is determined that there is a following vehicle in the right adjacent lane, but the vehicle is not approaching quickly, and the right adjacent lane approaching vehicle flag (F_Ri
ghLaneCar) is reset to “0” (S
610). Also, when there is no following vehicle in the right adjacent lane (F_Right Lane = 0) (S601)
NO), the right adjacent lane approaching vehicle flag (F_Right
LaneCar) is reset to “0” (S61).
0).

When there is no following vehicle in the right adjacent lane, it is further determined whether there is a following vehicle in the left adjacent lane, that is, the left adjacent lane flag (F_LeftLane).
Is set to “1” (S6).
05). When there is a following vehicle in the left adjacent lane, the headway time Thl is calculated based on the detection distance Rl calculated based on the detection signal from the left radar sensor and the relative speed Vl calculated based on the detection distance Rl. It is calculated according to the following equation (S606).

Thl = Rl / Vl Further, it is determined whether or not the calculated headway time Thl is longer than a predetermined time Thmin (S60).
7). When the headway time Th1 is equal to or shorter than the predetermined time Thmin (NO in S607), it is determined that there is a following vehicle that quickly approaches the host vehicle 100 in the left adjacent lane, and the left adjacent lane approaching vehicle flag (F_LeftLaneCar) is set to “1”. (S608).

On the other hand, if there is no following vehicle in the left adjacent lane (F_LeftLane = 0, NO in S605)
And when the headway time Th1 is shorter than a predetermined time (S
607) is a left adjacent lane approaching vehicle flag (F_
LeftLaneCar) is reset to “0” (S609). The alarm output process subsequent to the approach obstacle discrimination process (S6) executed in the above procedure is executed, for example, according to the procedure shown in FIG.

In FIG. 20, first, it is determined based on the detection signal from the direction indicator sensor 24 whether or not a rightward direction has been designated (S701). Here, when it is determined that the direction instruction to the right has been performed,
The right adjacent lane approaching vehicle flag (F_RightLa) that is set and reset in the approaching obstacle determination process (S6).
neCar) is set to “1” (S702), and the right lane parallel running flag (F_Right) is set and reset in the parallel running vehicle determination process (S5).
It is determined whether or not (tLaneH) is set to “1” (S703). If the right adjacent vehicle approaching vehicle flag (F_Right Lane Car) or the right lane parallel running flag (F_Right Lane H) is set to “1”, the control unit 30
Supplies the right alarm control signal and the obstacle information to the alarm output device 40 (S704). As a result, the alarm output device 40 turns on the alarm lamp indicating the right lane, and outputs obstacle information, for example, a message (F_Right) indicating that a following vehicle is rapidly approaching from the right adjacent lane.
(Corresponding to LaneCar = 1) or a message (F_Right) indicating that there is another vehicle running in the right adjacent lane.
(Corresponding to LaneH = 1) is displayed or output as audio.

On the other hand, if the above-described rightward direction instruction has not been made (NO in S701), it is further determined whether or not a leftward direction instruction has been made based on the detection signal from the direction indicator sensor 24. Is determined (S705). When a left direction instruction is issued, the left adjacent lane approaching vehicle flag (F_LeftLane) is used in the same manner as the right direction instruction.
Car) is set to “1” or not (S
707), left lane parallel running flag (F_LeftLane)
H) is set to “1” (S70)
8) is performed.

If any one of the flags is set to "1", the control unit 30 supplies a left alarm control signal and obstacle information to the alarm output device 40 (S709). As a result, the warning output device 40 turns on the warning lamp indicating the left lane, and outputs obstacle information, for example, a message indicating that a following vehicle is rapidly approaching from the left adjacent lane (F_LeftLaneCar = 1).
Or a message (corresponding to F_LeftLaneH = 1) indicating that there is another vehicle running in the left adjacent lane in parallel is displayed or output as sound.

As described above, the driver who has performed a right or left direction instructing operation to change the lane of the vehicle 100 to the right adjacent lane or the left adjacent lane is provided by the alarm output device 4.
Based on the output information from 0, know the presence of a following vehicle that quickly approaches the vehicle 100 in the right or left adjacent lane, or the presence of another vehicle running in parallel with the vehicle 100 in the right or left adjacent lane. Can be. At this time, the driver
When the state of the vehicle in the adjacent lane is confirmed by a side mirror, a rearview mirror or the naked eye, and it is determined that safe lane change cannot be performed based on the actual confirmed state and the output information from the alarm output device 40, The driving operation for changing lanes can be stopped.

As described above, even if there is a following vehicle that rapidly approaches the adjacent lane or a vehicle that runs in parallel with the vehicle, unless a direction instruction operation to the right or left is performed (S701 and S701). (NO in S705), the alarm information is not output from the alarm output device 40. Even if the warning lamp is turned on or the warning message is output by the warning output device 40 as described above, when the driver attempts to perform the steering operation for changing the lane, a more urgent warning is issued. For this purpose, the following processing is further executed.

First, it is determined based on the detection signal from the steering sensor 26 whether or not a rightward steering operation has been performed (S710). When the steering operation to the right is performed, when the right adjacent lane approaching vehicle flag (F_RightLaneCar) is set to “1” (S711), or when the right lane parallel running flag (F_RightLaneH) is set. If it is set to “1” (S712), the control unit 30
Supplies the emergency alert control signal to the alert output device 40 (S713). As a result, the alarm output device 40 outputs a predetermined alarm sound to draw the driver's attention.

When the steering operation to the left is performed (NO in S710 and YES in S714), similarly to the steering operation to the right, the left adjacent lane approaching vehicle flag (F_LeftLaneCar) is set to “ It is determined whether or not “1” is set (S715),
It is determined whether the left lane parallel running flag (F_LeftLaneH) is set to “1” (S716). If any one of the flags is set to “1”, the control unit 30
Supplies an emergency alarm control signal to the alarm output device 40 (S713), and the alarm output device 40 emits an alarm sound.

As described above, the driver who has started the steering operation can stop the steering operation for changing lanes by the alarm sound emitted from the alarm device 40. Even in this case, even when a following vehicle is rapidly approaching the adjacent lane or when another vehicle is running in parallel with the vehicle 100 in the adjacent lane, the driver can perform steering operation for changing lanes. Is not performed, the alarm output device 40 does not generate an alarm sound.

[0120] Instead of the alarm sound from the alarm output device 40, the driver can be provided with an emergency alarm by another method such as by vibrating the steering wheel. In the above example, steps S1 and S1 in FIG.
The processing in 2 corresponds to the first calculation means and the second calculation means. The processing in steps S402 and S403 or the processing in steps S415 and S416 shown in FIG. 10 corresponds to the azimuth calculating means.

The processing in step S401 shown in FIG. 10 corresponds to the speed determining means, and the processing procedure after the result of the determination in step S401 (YES, NO) corresponds to the selecting means.
The processing in step S404 corresponds to the curvature estimating means, and the processing in steps S406 and S407 and the processing in steps S411 and S412 correspond to the vehicle adjacent lane determining means.

The processing in step S511 in FIG. 18 and the processing in step S521 correspond to the distance determining means, and the processing in steps S513, S514 and S515, and the processing in steps S523, S524 and S525.
Corresponds to the parallel running information generating means. The processing in step S602 in FIG. 19 and step S605
Corresponds to the approach information calculation means, and the process in step S60
The processing in step 3 and the processing in step S607 correspond to the approach speed determining means, and the processing in step 604,
The process in step S608 corresponds to an object approach information generation unit.

The processing in step S701, the processing in step S705, the processing in step S710, and the processing in step S714 in FIG. 20 correspond to the lane change intention determination means, the processing in step S703, and the processing in step S708. The processing in step S712, the processing in step S712, and the processing in step S716 correspond to a determination unit that determines whether or not parallel running information has been generated.
, Processing in step S709, and step S71
The process in step 3 and the process in step S716 and the alarm output device 40 correspond to an alarm output unit.

Further, the processing in step S702, the processing in step S707, and the step S711 in FIG.
The process in step S715 and the process in step S715 correspond to a determination unit that determines whether the object proximity information has been generated. Further, the processing in step S3 shown in FIG. 5 corresponds to the change information calculating means and the allocating means.

[0125]

As described above, each of the claims 1
According to the present invention described in any one of (1) to (9), the azimuth of the object from the vehicle is obtained along with the information depending on the relative position between the object and the vehicle existing on the rear side of the vehicle. The relative positional relationship with the object can be detected with higher accuracy.

According to the tenth aspect of the present invention, even if a plurality of objects are present in each of the overlapping monitoring areas at the same time, based on the detection signals from the first radar sensor and the second radar sensor. Each piece of information depending on the relative position between the object and the vehicle calculated by the calculation can be assigned to each object. As a result, even if a plurality of objects are present on the rear side of the vehicle, it can be detected with higher accuracy than the relative positional relationship between the vehicle and each object behind.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of installation of a radar sensor in a vehicle periphery monitoring device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a monitoring area formed on the right rear side of the vehicle by two radar sensors shown in FIG. 1;

FIG. 3 is a diagram showing a monitoring area formed on the left rear side of the vehicle by the other two radar sensors shown in FIG. 1;

FIG. 4 is a block diagram illustrating a configuration example of a vehicle periphery monitoring device according to an embodiment of the present invention.

FIG. 5 is a flowchart showing a procedure of a monitoring process executed by a control unit of the vehicle periphery monitoring device shown in FIG.

FIG. 6 is a diagram illustrating an example of a relationship between a vehicle equipped with a vehicle periphery monitoring device and a following vehicle.

FIG. 7 is a diagram illustrating a relationship between a transmission pulse wave and a reception pulse wave of each radar sensor.

FIG. 8 is a diagram showing a relationship between a relative speed between a vehicle equipped with the vehicle periphery monitoring device and a following vehicle and a position of each following vehicle.

FIG. 9 is a diagram showing a state of a relative speed change rate in each traveling lane of a following vehicle.

10 is a flowchart showing a procedure of a traveling lane discriminating process in the monitoring process shown in FIG.

FIG. 11 is a diagram showing a relationship between a ratio (relative speed ratio) between a right detected relative speed and a left detected relative speed of a following vehicle and a position of the following vehicle.

FIG. 12 is a diagram showing a relationship between a relative speed ratio (relative distance ratio) and an azimuth angle.

FIG. 13 is a diagram showing a relationship between a relative speed ratio and an azimuth at each detection distance.

FIG. 14 is a diagram showing a relationship between an adjacent lane determination threshold and a curve radius on a right curve road.

FIG. 15 is a diagram showing a relationship between a vehicle equipped with a vehicle periphery monitoring device on a right curve road and a following vehicle traveling in an adjacent lane.

FIG. 16 is a diagram showing a relationship between an adjacent lane discrimination threshold and a curve radius in a left curve.

FIG. 17 is a diagram showing a relationship between a vehicle equipped with a vehicle periphery monitoring device on a left curve road and a following vehicle traveling in an adjacent lane.

18 is a flowchart illustrating a procedure of a parallel running vehicle determination process in the monitoring process illustrated in FIG. 5;

FIG. 19 is a flowchart illustrating a procedure of an approaching obstacle determination process in the monitoring process illustrated in FIG. 5;

20 is a flowchart showing a procedure of an alarm output process in the monitoring process shown in FIG.

[Explanation of symbols]

 12 Right outside radar sensor (RRO) 14 Right inside radar sensor (RRI) 16 Left outside radar sensor (RLO) 18 Left inside radar sensor (RLI) 20 Multiplexer 22 A / D converter 24 Direction indicator sensor 26 Steering sensor 28 Vehicle speed Sensor 30 Control unit 40 Alarm output device 100 Vehicle 200, 300 Subsequent vehicle

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G08G 1/16 G01S 13/93 Z // B62D 101: 00 F term (Reference) 3D032 CC30 DA23 DA74 DA77 DA84 DA88 DB01 DB02 DB03 DB11 DC31 DD13 DE00 EA01 EA02 EA04 EB30 EC40 GG01 5H180 CC03 CC14 LL02 LL04 LL07 5J070 AB01 AC02 AC06 AC11 AE01 AF03 AH31 AK22 BF12

Claims (10)

[Claims] 1. A vehicle periphery monitoring device that detects a relative positional relationship with an object on the rear side of a vehicle using a radar sensor that detects a distance from the object. A first radar sensor that forms a first monitoring area on the rear side of the vehicle, and is installed at a different position from the first radar sensor in a rear part of the vehicle, and the first monitoring area A second radar sensor forming an overlapping second monitoring area; and information dependent on a relative position between an object in the first monitoring area and the vehicle based on a detection signal from the first radar sensor. And a second calculation for calculating information dependent on the relative position between the object in the second monitoring area and the vehicle based on a detection signal from the second radar sensor. Means; Azimuth calculating means for calculating the azimuth from the vehicle of an object commonly present in the overlapping first and second monitoring areas based on the respective information calculated by the two calculating means. Monitoring device. 2. The vehicle periphery monitoring device according to claim 1, wherein the first calculating means determines a relative speed of the object with respect to the vehicle based on a detection signal from the first radar sensor. While calculating as information depending on the position, the second calculating means also calculates the relative speed of the object with respect to the vehicle based on the detection signal from the second radar sensor as information depending on the relative position of the object. Calculating the azimuth calculating means, a relative speed ratio calculating means for calculating a ratio of each relative speed calculated by the first calculating means and the second calculating means, and calculating by the relative speed ratio calculating means And a relative speed ratio corresponding direction calculating means for calculating the direction of the object from the vehicle based on the ratio of the respective relative speeds. 3. The vehicle periphery monitoring device according to claim 1, wherein the first calculating means determines a relative distance between the object and the vehicle based on a detection signal from a first radar sensor. And the second computing means also depends on the relative position of the object and the vehicle based on the detection signal from the second radar sensor, depending on the relative position of the object. Calculating as information, the azimuth calculating means calculates a relative distance ratio calculating means for calculating a ratio of each relative distance calculated by the first and second calculating means, and a relative distance ratio calculating means calculating the ratio. And a relative distance corresponding direction calculating means for calculating the direction of the object from the vehicle based on a ratio of the relative distances. 4. The vehicle surroundings monitoring device according to claim 1, wherein the first calculating means is configured to determine a relative distance between the object and the vehicle based on a detection signal from the first radar sensor and an object with respect to the vehicle. The relative speed is calculated as information depending on the relative position of the object, and the second calculating means also calculates the relative distance between the object and the vehicle based on the detection signal from the second radar sensor and the object. The relative speed with respect to the vehicle is calculated as information depending on the relative position of the object, and the azimuth calculating means calculates a relative distance ratio calculated by the first and second calculating means. Distance ratio calculating means, relative speed ratio calculating means for calculating a ratio of each relative speed calculated by the first and second calculating means, and relative speed ratio calculating means for calculating the relative distance calculated by the relative distance ratio calculating means. Based on ratio A relative distance corresponding direction calculating means for calculating the direction of the object from the vehicle; and a relative speed for calculating the direction of the object from the vehicle based on the ratio of the relative speeds calculated by the relative speed ratio calculating means. Corresponding azimuth calculating means, and speed determination for determining whether or not the relative speed of the object calculated based on the detection signal from the first radar sensor or the detection signal from the second radar sensor is smaller than a predetermined value. Means, when the speed determining means determines that the relative speed of the object is smaller than a predetermined value, selecting the azimuth calculated by the relative distance corresponding azimuth calculating means as output information of the azimuth calculating means, When the speed determination means determines that the relative speed of the object is not smaller than a predetermined value, the azimuth calculated by the azimuth calculation means corresponding to the relative speed is output information of the azimuth calculation means. A vehicle periphery monitoring device provided with a selection means for selecting and. 5. The vehicle surroundings monitoring device according to claim 1, wherein a curvature estimating means for estimating and calculating a curvature of a road on which the vehicle travels; A relative distance to the object calculated based on at least one of the above, an azimuth from the vehicle of the object calculated by the azimuth calculating means, a curvature of the road estimated by the curvature estimating means, and a lane of the road; A vehicle periphery monitoring device having vehicle adjacent lane determination means for determining whether or not the object is present in a lane adjacent to a lane in which the vehicle travels based on information on a structure. 6. The vehicle radar according to claim 5, wherein the first radar is provided when the vehicle adjacent lane determining means determines that the object is present in a lane adjacent to the lane in which the vehicle travels. Distance determining means for determining whether the relative distance to the object calculated based on at least one of the detection signals from the sensor and the second radar sensor is smaller than a predetermined value; And a parallel running information generating means for generating parallel running information indicating that the object moves near the vehicle in an adjacent lane when the distance determining means determines that the distance is smaller than the value. 7. The vehicle radar according to claim 5, wherein when the vehicle adjacent lane determining means determines that the object is present in a lane adjacent to a lane in which the vehicle travels, the first radar is provided. Approach information calculating means for calculating information representing the degree of speed of an object moving in the adjacent lane based on at least one of the detection signals from the sensor and the second radar sensor; Approach speed determining means for determining whether the information represents a speed greater than a predetermined speed, and when the approach speed determining means determines that the information represents a speed greater than a predetermined speed, A vehicle periphery monitoring device comprising: object approach information generation means for generating object approach information indicating that fact. 8. A vehicle periphery monitoring apparatus according to claim 6, wherein said lane change intention determining means determines whether or not the driver has an intention to change lanes, and said lane when said driver has an intention to change lanes. When the change intention determining means determines, the parallel running information indicating that an object moves in the vicinity of the vehicle in the adjacent lane to be changed by the driver is generated by the parallel running information generating means. A vehicle periphery monitoring device comprising: a determination unit that determines; and an alarm output unit that outputs alarm information to a driver when the determination unit determines that the parallel running information has been generated. 9. A vehicle periphery monitoring device according to claim 7, wherein a lane change intention determining means for judging whether or not the driver has an intention to change lanes, and said lane when said driver has an intention to change lanes. When the change intention determining means determines, the object approach information generating means generates object approach information indicating that the object is moving at a speed greater than a predetermined speed in the adjacent lane to be changed by the driver. A vehicle periphery monitoring device comprising: a determination unit configured to determine whether the object proximity information has been generated; and an alarm output unit configured to output warning information to a driver when the determination unit determines that the object proximity information has been generated. 10. A vehicle periphery monitoring device for detecting a relative positional relationship with an object on the rear side of a vehicle using a radar sensor for detecting a distance from the object, wherein the device is installed at a rear portion of the vehicle. A first radar sensor that forms a first monitoring area on the rear side of the vehicle, and is installed at a different position from the first radar sensor in a rear part of the vehicle, and the first monitoring area A second radar sensor forming an overlapping second monitoring area; and information dependent on a relative position between an object in the first monitoring area and the vehicle based on a detection signal from the first radar sensor. And a second calculation for calculating information dependent on the relative position between the object in the second monitoring area and the vehicle based on a detection signal from the second radar sensor. Means and the first When there are a plurality of pieces of information depending on the relative position between the object calculated by the calculating means and the second calculating means and the vehicle, respectively, the object is calculated based on the information obtained by the first calculating means. Calculating the first change information depending on the change in the relative speed of the object, and calculating the second change information depending on the change in the relative speed of the object based on the information obtained by the second calculating means. An information calculating means, and an object calculated by the first calculating means and the second calculating means corresponding to the pair in the order from the closer pair of the first change information and the second change information, and the vehicle Allocation means for allocating each piece of information depending on the relative position to the same object.