JPH06290398A - Obstacle detector - Google Patents

Abstract

PURPOSE:To properly detect an obstacle by correcting the detected angle based on deviation and correcting the error of the obstacle detection direction in the case of the occurrence of the deviation of the detection direction for the proceeding direction of a vehicle. CONSTITUTION:The signal from an obstacle detecting circuit 4 is inputted to an inter-vehicle distance deciding circuit 6 and a straight proceeding state judging circuit 7, and the signal from a proceeding course estimating circuit 5 is inputted to the inter-vehicle distance deciding circuit 6, and an obstacle closest to the vehicle on a proceeding course is assumed as a proceeding vehicle C2 to obtain an inter-vehicle distance L. The straight proceeding state circuit 7 judges that the vehicle is judged as in the straight proceeding state when some of obtained distances to obstacles are equal to each other. The signal from the straight proceeding state judging circuit 7 is inputted to an angle correcting circuit 8 to correct the detected angle based on the deviation of the detection direction of a laser radar device 1 for the proceeding direction of the vehicle, and the angle of steering of a steering sensor 2 at the time is corrected to zero.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an obstacle detecting device, and more particularly to an obstacle detecting device used for detecting an inter-vehicle distance from a preceding vehicle while the automobile is running.

[0002]

2. Description of the Related Art In recent years, an auto cruise control technology for automatically driving a car at a constant speed has been developed and put into practical use.
In that case, if you continue auto cruise traveling, the inter-vehicle distance between your vehicle and the preceding vehicle may decrease,
There is a problem that the brakes are forced to operate, and as a result, the auto-cruise travel cannot continue.

Therefore, while keeping the inter-vehicle distance constant,
There is a demand that it will be extremely convenient if it is possible to perform auto cruise driving.

By the way, in order to keep the inter-vehicle distance constant, it is necessary to accurately detect the position and direction of the preceding vehicle. Therefore, a device for detecting this is required.

In this type of detection device, a radar wave such as a light wave, an electric wave, or an ultrasonic wave is emitted from the transmitting portion toward the front of the vehicle, and the radar wave hits an obstacle such as a preceding vehicle and is reflected. It is well known that the receiving unit receives a signal from a vehicle and detects the distance between the obstacle and the host vehicle based on the delay time between the reception time and the transmission time (for example, Japanese Unexamined Patent Application Publication No. 61-61160). (See Japanese Patent No. 162776). As such a detection device, a scan type radar device that scans radar waves from side to side is used, and it is possible to detect an obstacle in a relatively wide range and also to detect the direction of the obstacle. is there.

[0006]

By the way, in the obstacle detecting device as described above, when the direction of the obstacle is obtained, the traveling direction line of the host vehicle when the vehicle is traveling straight when the steering angle is zero is used as the reference line. , The radar scan center line (in other words, the detection direction) must be fitted to the vehicle body in a state in which the reference line is matched, but in that case, an assembly error may occur. In addition, even when the scan center line and the vehicle body center line are aligned during assembly, if the left and right tire diameters differ due to changes over time, etc., straight steering with a steering angle of zero will occur. At this time, the traveling direction line of the vehicle body does not coincide with the vehicle body center line and the scan center line, and there is a possibility that an obstacle may be erroneously detected due to this inconsistency.

The present invention has been made in view of the above points, and corrects the detection angle based on the deviation of the detection direction by the obstacle detection means with respect to the traveling direction of the host vehicle, thereby detecting the obstacle. The purpose is to be able to perform properly.

[0008]

According to a first aspect of the present invention, as means for solving the above-mentioned problems, there is provided obstacle detection means for detecting an obstacle existing in front of a traveling vehicle, and the obstacle detection means is provided. In an obstacle detection device that detects the position and direction of an obstacle with respect to the traveling direction of the own vehicle based on data from the detection means, the straight traveling state of the own vehicle is determined based on the detection state of the preceding vehicle by the obstacle detection means. A straight traveling state determining means, and when the straight traveling state determining means determines that the host vehicle is in the straight traveling state, the detected angle is corrected based on the deviation of the detection direction by the obstacle detecting means with respect to the traveling direction of the host vehicle. A correction means is attached.

According to a second aspect of the present invention, as means for solving the above-mentioned problems, in the obstacle detection device according to the first aspect, the straight-ahead traveling state determining means is provided up to two reflectors provided on the preceding vehicle. When the detection distances are equal, it is determined that the vehicle is in a straight traveling state.

According to a third aspect of the present invention, as means for solving the above-mentioned problems, in the obstacle detection device according to the first aspect, the straight-ahead traveling state determination means is provided with a large number of obstacles located in front of the host vehicle. Among these detection directions, the direction with the highest detection frequency within a predetermined time is determined to be the straight traveling direction of the host vehicle.

According to a fourth aspect of the present invention, as means for solving the above-mentioned problems, in the obstacle detection device according to the first aspect, the correction means is a traveling direction detection means for detecting the traveling direction of the host vehicle. It is supposed to be corrected.

[0012]

According to the first aspect of the invention, the following actions can be obtained by the above means.

That is, when the traveling vehicle is in a straight traveling state, if there is a deviation in the detection direction of the obstacle detection means with respect to the traveling direction of the own vehicle, the detected angle is corrected based on the deviation. Thus, the assembling error of the obstacle detecting means and the error in the obstacle detecting direction due to the difference between the left and right tire diameters due to the secular change will be corrected.

According to the second aspect of the invention, the following effects can be obtained by the above means.

That is, when the detected distances to the two reflectors provided on the preceding vehicle are equal, it means that the host vehicle is in a straight traveling state with respect to the preceding vehicle. It is supposed to do.

According to the invention of claim 3, the following effects can be obtained by the above means.

That is, the detection direction of many obstacles located in front of the host vehicle is taken in, and the direction with the highest detection frequency within the predetermined time is the direction in which the preceding vehicle is detected. Will be determined to be a straight direction.

According to the invention of claim 4, the following effects can be obtained by the above means.

That is, when there is a deviation in the detection direction of the obstacle detection means with respect to the traveling direction of the host vehicle, the traveling direction detection means for detecting the traveling direction of the host vehicle is corrected based on the deviation. Becomes

[0020]

According to the first, second or third aspect of the present invention, when the traveling vehicle is in a straight traveling state, there is a deviation in the detection direction by the obstacle detecting means with respect to the traveling direction of the own vehicle. In addition, since the detection angle is corrected based on the deviation, the error in the obstacle detection direction due to the assembly error of the obstacle detection means and the difference in the left and right tire diameters due to aging can be corrected. Object (for example, preceding vehicle)
There is an excellent effect that the accuracy of direction detection can be significantly increased.

According to the fourth aspect of the invention, when there is a deviation in the detection direction of the obstacle detection means with respect to the traveling direction of the own vehicle, the deviation is detected by the traveling direction detection means for detecting the traveling direction of the own vehicle. Since the correction is performed based on the above, there is an excellent effect that it is possible to improve the accuracy of the traveling direction of the host vehicle.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment FIGS. 1 to 6 show an automatic cruise control device equipped with an obstacle detection device according to a first embodiment of the present invention. The present embodiment corresponds to the inventions of claims 1, 2 and 4.

FIG. 1 is a block diagram of an obstacle detecting device according to the first embodiment of the present invention. This obstacle detection device is equipped with an auto cruise control device for a vehicle, and is used to detect the inter-vehicle distance between the host vehicle and the preceding vehicle based on the obstacle information detected by the obstacle detection device. It is supposed to be done.

In FIG. 1, reference numeral 1 is a laser radar device acting as an obstacle detecting means. The laser radar apparatus 1, as shown in FIG. 2, which is provided at the front center of the vehicle C _1, transmits toward the front of the vehicle C ₁ pulsed laser light from the transmitting unit as radar wave with obstacle An (n = 1, such as the preceding vehicle C ₂ present ahead,
2) is reflected by the receiving section. In addition, the laser radar device 1 is
It is of a scan type in which the pulsed laser light emitted from the transmission unit is scanned in a horizontal direction at a relatively wide angle.
The signal from the laser radar device 1 is input to the obstacle detection circuit 4, and in the obstacle detection circuit 4, each obstacle An (n = 1,2 ...) and the distance Ln (n = 1, 2 ... between the vehicle C ₁₎ and each obstacle an (n = 1, 2 ...)
The detected angle Ψn (n = 1, 2 ...) With respect to the host vehicle C ₁ is calculated. Here, the detected angle Ψn is determined by the scanning center line O of the laser radar device 1 and the obstacle An (n
= 1,2 ...) And the line Fn (n = 1,2 ...) that connects the vehicle C ₁
It is said to be an angle with.

Further, reference numeral 2 denotes a steering angle sensor for detecting a steering angle theta, 3 is a speed sensor for detecting a vehicle speed V of the vehicle C _1, the detection signals of both sensors 2 and 3 are traveling path estimation circuit 5 is input to the traveling path estimation circuit 5, and the traveling path R (see FIG. 3) of the host vehicle C ₁ is estimated from the relationship between the steering angle θ and the vehicle speed V.

The signal from the obstacle detection circuit 4 is input to the inter-vehicle distance determination circuit 6 and the straight traveling state determination circuit 7, and the signal from the traveling path estimation circuit 5 is input to the inter-vehicle distance determination circuit 6 to determine the inter-vehicle distance. In the circuit 6, the inter-vehicle distance L is determined with the closest vehicle on the traveling route R as the preceding vehicle C ₂ , and in the straight traveling state determination circuit 7, the determined obstacle An (n = 1, 2 ,.・ Distance to Ln (n = 1,
2) are equal (for example, when the detection distances L ₅ and L ₆ to the two reflectors A ₅ and A ₆ provided on the preceding vehicle C ₂ are equal), the host vehicle C ₁ goes straight. It is to be judged as a state. In this embodiment, the straight-ahead traveling state determination circuit 7 constitutes the straight-ahead traveling state determining means in the claims.

The signal from the straight-ahead traveling state determination circuit 7 is input to a detection angle correction circuit 8, and in the detection angle correction circuit 8, the detection direction (in other words, the detection direction by the laser radar device 1 with respect to the traveling direction O ₀ of the vehicle C ₁ is changed. Then, the detected angle is corrected based on the deviation ΔΨ of the scan center line O), and the steering angle θ of the steering angle sensor 2 at that time is corrected to zero. In this embodiment,
The detection angle correction circuit 8 constitutes the correction means in the claims.

The signal from the inter-vehicle distance determination circuit 6 is input to the auto cruise control circuit 10 together with the signal from the auto cruise switch 9, various determinations and calculations are performed in the auto cruise control circuit 10, and the control signal resulting therefrom is used. Is output to the throttle valve control device 11 that performs engine output control.

Next, with reference to the flow charts shown in FIGS. 4 to 6, the operation of the obstacle detecting device according to the present embodiment and the automatic cruise control of the vehicle equipped with the obstacle detecting device will be described.

(I) Detection Angle Correction (Detection Angle Correction Routine) In step S ₁ in the flowchart of FIG. 4, the distance Ln of the obstacle An that reflects the pulsed laser light emitted from the laser radar device 1 and the detection angle Ψn are obstructed. The object detection circuit 4 picks up the object, and in step S ₂ , it is determined whether or not there are obstacles An having the same distance Ln. The determination is that the preceding vehicle C is an obstacle.
When taking a reflector A _5, A ₆ of _2, if I have the vehicle C ₁ is straight, the distance L _5, L ₆ to the reflector A _5, A ₆ is intended to be made in view of the point equal Yes, when L ₅ = L _6, the host vehicle C ₁ is determined to be in a straight traveling state. In addition,
In this embodiment, positive determination is made in step S ₂ in the case where (in other words, L ₅ = L ₆ and determination) have been, in step S ₃ L ₅ = conditions of L ₆ is a predetermined time (e.g., 10 seconds ) Check if it is continuing and make a straight-ahead judgment.

If an affirmative determination is made in step S ₃ (that is, if the host vehicle C ₁ is determined to be in a straight traveling state), step S 3
_{At 4} , the detection angle of the laser radar device 1 is corrected. The detection angle correction corrects the deviation ΔΨ between the scan center line O of the laser radar device 1 and the traveling direction O ₀ of the host vehicle C ₁ (that is, the center direction between the reflectors A ₅ and A ₆ ) to zero (ie, , Correction for making the scan center line O coincide with the traveling direction O ₀ )
Run as.

Next, in step S ₅ , the steering angle sensor 3 is corrected. The correction is performed by correcting the detected steering angle θ of the steering angle sensor 2 to zero at the time when it is determined that the vehicle is traveling straight.

According to the above, the laser radar device 1
Error in the obstacle detection direction due to the difference between the left and right tire diameters due to the secular change can be corrected, and the accuracy of the direction detection of the front obstacle (for example, the preceding vehicle C ₂ ) can be significantly improved. Therefore, the accuracy of detecting the traveling direction can be improved.

(II) Inter-Vehicle Distance Detection (Inter-Vehicle Distance Detection Routine) Signals from the auto cruise switch 9, the steering angle sensor 2 and the vehicle speed sensor 3 are input at step S ₁ in the flowchart of FIG. 5, and auto cruise at step S ₂ . When it is determined that the switch 9 is turned on, the traveling road estimation circuit 5 estimates the traveling road R (see FIG. 3) of the host vehicle C ₁ from the steering angle θ and the vehicle speed V in step S ₃ . Then, in step S ₄ , the obstacle closest to the traveling route R is set to the preceding vehicle C ₂
And the inter-vehicle distance L with the preceding vehicle C ₂ is calculated.

(III) Auto Cruise Control (Auto Cruise Control Routine) At step S ₁ in the flow chart of FIG. 6, the ON signal of the auto cruise switch 9, the auto cruise setting vehicle speed V ₀ from the auto cruise setting device (not shown), the vehicle speed When the vehicle speed V of the host vehicle C ₁ and the inter-vehicle distance L obtained in the inter-vehicle distance detection routine of FIG. 5 are input from the sensor 3 and it is determined in step S ₂ that the auto cruise switch 9 is ON. In step S ₃ , an appropriate set inter-vehicle distance L ₀ according to the vehicle speed V is read from the map shown in FIG. 7.

Thereafter, in step S ₄ , the inter-vehicle distance L obtained in the above-mentioned inter-vehicle distance routine is compared with the set inter-vehicle distance L ₀ read in step S ₃ , and it is determined that L≤L _0. the process proceeds to step S _5, the output of the engine is controlled to be the set inter-vehicle distance L _0. On the other hand, if L> L ₀ is determined in step S ₄ , the process proceeds to step S ₆ and the output of the engine is controlled so that the control vehicle speed V ₀ is reached.

Embodiment 2 FIGS. 8 and 9 are flow charts for explaining the operation of the obstacle detecting device according to Embodiment 2 of the present invention. The present embodiment corresponds to the inventions of claims 1, 3 and 4.

In the case of the present embodiment, the straight traveling state judging circuit 7 (see FIG. 1) acting as the straight traveling state judging means is provided with the vehicle C ₁
Of the many obstacles An (n = 1, 2 ...) Which are located in front of the vehicle, the direction with the highest detection frequency within a predetermined time is detected by the host vehicle C ₁ . It is determined that the vehicle is going straight.

It is necessary to accumulate the data for determining the straight traveling state every predetermined traveling distance (1 km in this embodiment).

The data accumulating procedure will be described in detail based on the data accumulating routine shown in FIG. 8. In step S ₁ , the obstacle An (n = 1, 2, ...) Is scanned by the laser radar device 1 (see FIG. 10). seeking in the sensing direction Ψn (n = 1,2 ··), the predetermined distance (in this embodiment in step S _2, 1
km) Obstacle detection direction Ψn (n = 1,2 ・
The accumulation of data is completed by adding the accumulation frequency of () to create the distribution chart shown in FIG. This means that the preceding vehicle C ₂ exists in the direction with the highest detection frequency among the obstacle detection directions Ψn (n = 1, 2, ...) In this distribution map. It can be estimated as the straight direction of the vehicle C ₁ .

Next, the procedure of the detected angle correction using the results obtained by the data accumulation routine will be described with reference to the flowchart (detected angle correction routine) shown in FIG.

In step S ₁ , the laser radar device 1
The detected angle Ψn (n = 1, 2 ...) And its cumulative frequency (see FIG. 11) are input, and in step S ₂ , the preceding vehicle C is moved in the angular direction with the highest detection frequency as described above. _Assuming that ₂ exists, this direction is estimated as the straight traveling direction O ₀ of the host vehicle C ₁ , and both are matched based on the deviation ΔΨ from the scan center line O of the laser radar device 1 (that is, the scan center line O Is made to coincide with the straight traveling direction of the host vehicle C ₁ ).

Thereafter, in step S ₃ , a new detection direction Ψn (n = 1, 2 ...) Of the obstacle An (n = 1, 2 ...) By the laser radar device 1 is obtained, and Ψn is obtained in step S ₄ . After confirming that = 0, the detected angle θ of the steering angle sensor 2 at this time (see the dotted arrow in FIG. 1) is corrected to zero in step S ₅ . In addition, it is desirable that the above-described correction of the detected angle is executed every 100 km of travel distance.

With the above arrangement, the laser radar device 1
Error in the obstacle detection direction due to the difference between the left and right tire diameters due to the secular change can be corrected, and the accuracy of the direction detection of the front obstacle (for example, the preceding vehicle C ₂ ) can be significantly improved. Therefore, the accuracy of detecting the traveling direction can be improved.

[Brief description of drawings]

FIG. 1 is a block configuration diagram when an obstacle detection device according to an embodiment of the present invention is applied to automatic cruise control.

FIG. 2 is a schematic diagram showing a scanning mode by the laser radar device in the obstacle detection device according to the first embodiment of the present invention;

FIG. 3 is an explanatory diagram showing an aspect of inter-vehicle distance determination in the obstacle detection device according to the first embodiment of the present invention.

FIG. 4 is a flowchart (detection angle correction routine) for explaining the operation of the obstacle detection device according to the first embodiment of the present invention.

FIG. 5 is a flowchart (inter-vehicle distance determination routine) for explaining the inter-vehicle distance determination procedure using the obstacle detection device according to the first embodiment of the present invention.

FIG. 6 is a flowchart (auto cruise control routine) for explaining auto cruise control using the obstacle detection device according to the first embodiment of the present invention.

FIG. 7 is a map used in the flowchart (auto cruise control routine) of FIG.

FIG. 8 is a flowchart (data accumulation routine) for explaining a data accumulation procedure in the obstacle detection device according to the second embodiment of the present invention.

FIG. 9 is a flowchart (detection angle correction routine) for explaining the operation of the obstacle detection device according to the second embodiment of the present invention.

FIG. 10 is a schematic diagram showing a scanning mode by a laser radar device in an obstacle detection device according to a second embodiment of the present invention.

11 is a flowchart of FIG. 8 (data accumulation routine)
It is a data cumulative distribution map calculated | required in.

[Explanation of symbols]

1 is an obstacle detecting means (laser radar device), 2 is a steering angle sensor, 3 is a vehicle speed sensor, 4 is an obstacle detecting circuit, 5 is an advancing path estimating circuit, 7 is a straight traveling state determining means (straight traveling state determining circuit),
8 is a correction means (detection angle correction circuit), An (n = 1, 2 ...)
Is an obstacle, Ψn (n = 1, 2, ...) Is an obstacle detection angle, C ₁ is the own vehicle, and C ₂ is a preceding vehicle.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroe Ie 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Hideki Kaku, 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Stock In-company (72) Toshinori Toyohara, 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) In-house Takeshi Edahiro, 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture (72) Inventor Tetsuya Murakami 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Motor Corporation

Claims (4)

[Claims] 1. An obstacle detecting means for detecting an obstacle existing in front of a traveling own vehicle, wherein the position and direction of the obstacle with respect to the traveling direction of the own vehicle are determined based on data from the obstacle detecting means. An obstacle detection device for detecting,
A straight traveling state determination unit that determines the straight traveling state of the host vehicle based on the detection state of the preceding vehicle by the obstacle detection unit, and a straight traveling state determination unit that determines whether the host vehicle is in the straight traveling state by the straight traveling state determination unit. An obstacle detection device further comprising: a correction unit that corrects a detected angle based on a deviation of a detection direction of the obstacle detection unit with respect to a traveling direction. 2. The straight traveling state determination means is configured to determine that the host vehicle is in a straight traveling state when the detection distances to the two reflectors provided in the preceding vehicle are equal. The obstacle detection device according to item 1. 3. The straight-ahead traveling state determination means determines that the direction in which the detection frequency is the highest within a predetermined time, of the many obstacles located in front of the host vehicle, is the straight-ahead direction. The said 1 characterized by the above-mentioned.
The obstacle detection device described. 4. The obstacle detecting device according to claim 1, wherein the correcting means corrects a traveling direction detecting means for detecting a traveling direction of the own vehicle.