WO2020230231A1 - Obstacle detection device - Google Patents

Abstract

This obstacle detection device (100) comprises a reception control unit (21) for acquiring reception signals (RS) including a first reception signal (RS1) corresponding to a first reflected wave (RW1) reflected by an object (O) in the vicinity of a vehicle (1) and a second reception signal (RS2) corresponding to a second reflected wave (RW2) reflected by the object (O) in a direction different from the first reflected wave (RW1), an echo detection unit (22) for detecting echo groups (EG) including a first echo group (EG1) in the first reception signal (RS1) and a second echo group (EG2) in the second reception signal (RS2), and a first pedestrian determination unit (23) for, on the basis of detection results from the echo detection unit (22), determining that the object (O) is a pedestrian if there are a plurality of echoes (E) within a window (W) having a width corresponding to a pedestrian and outputting the result of the determination.

Description

Obstacle detector

The present invention relates to an obstacle detection device.

Conventionally, a device that detects an object such as an obstacle (hereinafter, simply referred to as an "object") around the vehicle by using a TOF (Time of Flight) type distance measuring sensor provided in the vehicle, that is, an obstacle detecting device. Has been developed. Patent Document 1 describes a technique for determining whether an object is a person or an object based on the waveform of a portion (hereinafter referred to as "echo") corresponding to a reflected wave by the object in the signal received by the distance measuring sensor. Is disclosed.

Fig. of Patent Document 1. By detecting the forest-like echo of No. 3, it is determined that the object is a person. This utilizes the fact that when the object is a human being, the surface shape of the reflective surface such as the torso, hands, and feet is complicated, so that it is highly probable that a forest echo will be detected. Here, the forest-like echo indicates a state in which a plurality of echoes are randomly generated at a certain distance.

U.S. Pat. No. 8,432,770

As will be described later with reference to FIG. 5, when the object is a pedestrian, the plate depends on the timing of irradiating the pedestrian with the exploration wave, the direction of irradiating the pedestrian with the exploration wave, the direction of reflection of the exploration wave by the pedestrian, and the like. Symptom echo may be detected. Therefore, for example, when it is determined whether the object is a pedestrian or a stationary object only based on the echo corresponding to the reflected wave in one direction by the object, the object walks based on the plate-shaped echo. Despite being a person, there was a problem that the object was misidentified as a stationary object.

The present invention has been made to solve the above problems, and an object of the present invention is to improve the accuracy of determining whether or not an object is a pedestrian.

The obstacle detection device of the present invention has a first received signal corresponding to a first reflected wave reflected by an object existing around the vehicle and a second reflected wave reflected by the object in a direction different from the first reflected wave. Detects an echo group including a reception control unit that acquires a reception signal including a second reception signal corresponding to the above, a first echo group in the first reception signal, and a second echo group in the second reception signal. Based on the detection results of the echo detection unit and the echo detection unit, when a plurality of echoes exist in a window having a width corresponding to a pedestrian, it is determined that the object is a pedestrian, and the determination result is obtained. It is provided with a first pedestrian discrimination unit for output.

According to the present invention, since it is configured as described above, it is possible to improve the accuracy of determining whether or not the object is a pedestrian.

It is a block diagram which shows the main part of the obstacle detection system including the obstacle detection device which concerns on Embodiment 1. FIG. It is explanatory drawing which shows the content of the processing executed by the transmission control unit, the reception control unit, and the echo detection unit. It is explanatory drawing which shows the example of the 1st echo group and the 2nd echo group when the exploration wave is reflected by one pole. It is explanatory drawing which shows the other example such as the 1st echo group and the 2nd echo group when the exploration wave is reflected by one pole. It is explanatory drawing which shows the example of the irradiation range of the exploration wave to a pedestrian, and the example of the reflection range of the exploration wave by a pedestrian. It is explanatory drawing which shows the example of the 1st echo group and the 2nd echo group when the exploration wave is reflected by a pedestrian. It is explanatory drawing which shows the other example such as the 1st echo group and the 2nd echo group when the exploration wave is reflected by a pedestrian. It is explanatory drawing which shows the content of the process executed by the body discriminating part. It is explanatory drawing which shows the content of other processing executed by the body discriminating part. It is explanatory drawing which shows the content of other processing executed by the body discriminating part. It is explanatory drawing which shows the content of other processing executed by the body discriminating part. It is explanatory drawing which shows the example of the state which the object is located in the predicted course range. It is explanatory drawing which shows the example of the state which the object is located outside the predicted course range. It is explanatory drawing which shows the example of the table for judgment in the warning necessity judgment part. It is explanatory drawing which shows the hardware configuration of the control device including the obstacle detection device which concerns on Embodiment 1. FIG. It is explanatory drawing which shows the other hardware configuration of the control device including the obstacle detection device which concerns on Embodiment 1. FIG. It is a flowchart which shows the operation of the control apparatus including the obstacle detection apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows the operation of the control apparatus including the obstacle detection apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows other operation of the control apparatus including the obstacle detection apparatus which concerns on Embodiment 1. FIG. It is explanatory drawing which shows another example of the irradiation range of the exploration wave to a pedestrian, and another example of the reflection range of the exploration wave by a pedestrian. It is a block diagram which shows the main part of the obstacle detection system including the obstacle detection device which concerns on Embodiment 2. FIG. It is a flowchart which shows the operation of the control device including the obstacle detection device which concerns on Embodiment 2. It is a flowchart which shows the operation of the control device including the obstacle detection device which concerns on Embodiment 2. It is a block diagram which shows the main part of the obstacle detection system including the obstacle detection apparatus which concerns on Embodiment 3. It is explanatory drawing which shows the example of the threshold value for discrimination in the 3rd pedestrian discrimination part. It is a flowchart which shows the operation of the control device including the obstacle detection device which concerns on Embodiment 3. It is a flowchart which shows the operation of the control device including the obstacle detection device which concerns on Embodiment 3.

Hereinafter, in order to explain the present invention in more detail, a mode for carrying out the present invention will be described with reference to the accompanying drawings.

Embodiment 1.
FIG. 1 is a block diagram showing a main part of an obstacle detection system including an obstacle detection device according to the first embodiment. An obstacle detection system including the obstacle detection device according to the first embodiment will be described with reference to FIG.

Vehicle 1 has N sonars 2 (N is an integer of 2 or more). Specifically, for example, four sonars 2_OR, 2_IR, 2_IL, and 2_OL are provided at the rear end of the vehicle 1. The rear sonar 3 is composed of these sonars 2_OR, 2_IR, 2_IL, and 2_OL. Each sonar 2 is capable of transmitting ultrasonic waves (hereinafter referred to as "exploration waves") TW behind the vehicle 1. Further, each sonar 2 is capable of receiving the reflected exploration wave (that is, the reflected wave) RW when the exploration wave is reflected by the object O existing behind the vehicle 1.

Vehicle 1 has a control device 4. The control device 4 is composed of, for example, an ECU (Electronic Control Unit). The vehicle 1 has sensors 5. The sensors 5 include, for example, a wheel speed sensor, a GPS (Global Positioning System) receiver, a yaw rate sensor, and a gyro sensor. The vehicle 1 has an output device 6. The output device 6 is composed of, for example, at least one of a display and a speaker. The display in the output device 6 is, for example, a liquid crystal display or an organic EL (Electro Luminescence) display.

The control device 4 has a transmission control unit 11. The control device 4 includes a reception control unit 21, an echo detection unit 22, a first pedestrian discrimination unit 23, and a body discrimination unit 24. The reception control unit 21, the echo detection unit 22, the first pedestrian discrimination unit 23, and the body discrimination unit 24 constitute the main part of the obstacle detection device 100. The control device 4 includes a vehicle information acquisition unit 12, a position calculation unit 13, a warning necessity determination unit 14, and a warning signal output unit 15.

In this way, the main part of the obstacle detection system 200 is configured.

Next, the operations of the transmission control unit 11, the reception control unit 21, and the echo detection unit 22 will be described with reference to FIG.

The transmission control unit 11 sequentially supplies an electric signal (hereinafter referred to as “transmission signal”) TS to N sonars 2 to sequentially transmit exploration wave TW to N sonars 2 (hereinafter referred to as “exploration wave”). "Transmission control") is executed. Specifically, for example, when the vehicle 1 is reversing, the transmission control unit 11 sequentially supplies the transmission signal TS to the four sonars 2_OR, 2_IR, 2_IL, and 2_OL, thereby causing the four sonars 2_OR, The exploration wave TW is sequentially transmitted to 2_IR, 2_IL, and 2_OL.

The exploration wave TW transmitted by each sonar 2 is, for example, a pulse wave modulated at a predetermined carrier frequency. From the viewpoint of avoiding interference between any two sonars 2 out of N sonars 2, the transmission control unit 11 uses so-called "time division multiplexing", "frequency division multiplexing" or "code division multiplexing" to perform rear sonar. It is preferable to control 3.

When an electric signal is output by each sonar 2, the reception control unit 21 acquires the output electric signal (hereinafter referred to as “received signal”) RS. The reception control unit 21 executes a process of detecting the object O (hereinafter referred to as “object detection process”) by comparing the intensity of the received signal RS with a predetermined threshold value Th1. In the figure, RS'indicates a signal corresponding to the result of the threshold value determination (hereinafter referred to as “determination result signal”). When the object O is detected by the object detection process, the reception control unit 21 outputs the reception signal RS to the echo detection unit 22.

Based on the result of the object detection process, the echo detection unit 22 executes a process of detecting a portion of the received signal RS corresponding to the reflected wave RW by the object O, that is, an echo E (hereinafter referred to as “echo detection process”). To do. More specifically, the echo detection unit 22 detects the one echo E when one echo E exists in the time window W_T having a predetermined width. On the other hand, when a plurality of echoes E are present in the time window W_T, the echo detection unit 22 detects the plurality of echoes E. Hereinafter, the group EG composed of one or more detected echoes E is referred to as an “echo group”.

Here, the time window W_T corresponds to the distance window W_D having a predetermined width. Hereinafter, the time window W_T and the distance window W_D are collectively referred to as a "window". The width of the window W is a standard value for the height of a general pedestrian (hereinafter referred to as "standard height"), a standard value for the swing width of the arm of a general pedestrian, or a standard value for the stride length of a general pedestrian. It is preset based on at least one of the values (hereinafter referred to as "reference stride"). For example, when the reference height is 180 centimeters and the reference stride is 80 centimeters, the width of the distance window W_D is set to 100 centimeters. This value includes the so-called "margin". As described above, the window W has a width corresponding to a pedestrian.

When the object O is detected by the object detection process, the reception control unit 21 determines the distance D by the following equation (1) for each part where the intensity in the received signal RS exceeds the threshold Th1 (that is, for each echo E). Is executed (hereinafter referred to as "distance measurement processing"). The distance D corresponds to the distance between the vehicle 1 and the object corresponding to each echo E (ie, object O or part of object O).

D = (PV x PT) / 2 (1)

Here, PV indicates the propagation velocity of the exploration wave TW in the air. The value of the propagation velocity PV is stored in advance in the reception control unit 21, for example. In addition, PT indicates the round-trip propagation time of the exploration wave TW. Therefore, PV × PT corresponds to the round-trip propagation distance PD of the exploration wave TW.

In the example shown in FIG. 2, two echoes E_1 and E_2 are detected. Further, two distances D_1 and D_2 (not shown) corresponding to the two echoes E_1 and E_2 are calculated based on the two reciprocating propagation times PT_1 and PT_2 corresponding to the two echoes E_1 and E_2. At this time, PV × PT_1 corresponds to the reciprocating propagation distance PD_1. Further, PV × PT_2 corresponds to the reciprocating propagation distance PD_2.

Here, in the obstacle detection system 200, the reflected wave RW received by the rear sonar 3 includes two reflected waves RW1 and RW2 reflected by the object O in different directions. The two reflected waves RW1 and RW2 are received by, for example, different sonars 2 out of N sonars 2. Hereinafter, the reflected wave RW1 of one of the two reflected waves RW1 and RW2 is referred to as a "first reflected wave". Further, the other reflected wave RW2 of the two reflected waves RW1 and RW2 is referred to as a "second reflected wave".

Therefore, in the obstacle detection device 100, the received signal RS acquired by the reception control unit 21 is the received signal RS1 corresponding to the first reflected wave RW1 (hereinafter referred to as “first received signal”) RS1 and the second reflected wave. It includes a received signal (hereinafter referred to as "second received signal") RS2 corresponding to RW2. The echo group EG detected by the echo detection unit 22 includes an echo group EG1 in the first received signal RS1 (hereinafter referred to as "first echo group") and an echo group in the second received signal RS2 (hereinafter referred to as "second echo group"). It is called "echo group".) It contains EG2.

Next, the operation of the first pedestrian discrimination unit 23 will be described with reference to FIGS. 3 to 7.

FIG. 3 shows an example of the first echo group EG1 and the second echo group EG2 when the object O is one pole.

As shown in FIG. 3, first, when the sonar 2_OR transmits the exploration wave TW1, the sonar 2_OR receives the first reflected wave RW1, the reception control unit 21 acquires the first reception signal RS1, and echo detection is performed. It is assumed that the unit 22 has detected the first echo group EG1. The exploration wave TW1 and the first reflected wave RW1 in this case have a so-called "direct wave" relationship. Next, when another sonar 2_OL transmits the exploration wave TW2, the sonar 2_OL receives the second reflected wave RW2, the reception control unit 21 acquires the second reception signal RS2, and the echo detection unit 22 receives the second reception signal RS2. 2 It is assumed that the echo group EG2 is detected. The exploration wave TW2 and the second reflected wave RW2 in this case have a direct wave relationship.

In the example shown in FIG. 3, the first echo group EG1 includes one echo E_1. This is a plate echo. Further, the second echo group EG2 includes one echo E_2. This is a plate echo.

FIG. 4 shows other examples such as the first echo group EG1 and the second echo group EG2 when the object O is one pole.

As shown in FIG. 4, when the sonar 2_OR transmits the exploration wave TW1, the sonar 2_OR receives the first reflected wave RW1, the reception control unit 21 acquires the first reception signal RS1, and the echo detection unit 22. Detected the first echo group EG1. The exploration wave TW1 and the first reflected wave RW1 in this case have a direct wave relationship. Further, at this time, another sonar 2_OL receives the second reflected wave RW2, the reception control unit 21 acquires the second reception signal RS2, and the echo detection unit 22 detects the second echo group EG2. To do. The exploration wave TW1 and the second reflected wave RW2 in this case have a so-called "indirect wave" relationship.

In the example shown in FIG. 4, the first echo group EG1 includes one echo E_1. This is a plate echo. Further, the second echo group EG2 includes one echo E_2. This is a plate echo.

In this way, when the object O is one pole, it is individual regardless of the irradiation timing of the exploration wave TW on the object O, the irradiation direction of the exploration wave TW on the object O, and the reflection direction of the exploration wave TW by the object O. The number of echoes E included in the echo group EG (hereinafter referred to as "the number of echoes") NE is constant. More specifically, the number of echoes NE is 1.

On the other hand, when the object O is a pedestrian, it becomes as follows.

Normally, the shape of a pedestrian is more complicated than the shape of a pole. Therefore, when the pedestrian is irradiated with the exploration wave TW, the exploration wave is generated by one or more parts of the pedestrian (for example, the head, torso, right arm, left arm, right leg and left leg). The TW is reflected. For example, when the mounting height of the rear sonar 3 is higher than the position of the pedestrian's waist and the irradiation direction of the exploration wave TW by each sonar 2 is set to be parallel to or substantially parallel to the road surface, mainly. The exploration wave TW is reflected by at least one part of the three parts including the torso, the right arm and the left arm.

As shown in FIG. 5, the pedestrian has a state in which the right arm is swung forward by the arm swing and the left leg is stepped forward in response to this (hereinafter referred to as "first state"). The state in which the left arm is swung forward by the arm swing and the right leg is stepped forward in response to this (hereinafter referred to as the "third state") and the intermediate state between these states, that is, both. The state in which the arms are placed right next to the torso (hereinafter referred to as "second state") is repeated.

A1 in FIG. 5 shows an example of a range in which the exploration wave TW is mainly irradiated (hereinafter referred to as “irradiation range”) when the object O is a pedestrian. Further, A2 in FIG. 5 shows an example of a range in which the exploration wave TW is mainly reflected (hereinafter referred to as “reflection range”) in this case.

As shown in FIG. 5, if the exploration wave TW is irradiated from the left side of the pedestrian and the pedestrian is in the first state or the third state, the left arm, the torso and the right arm are mainly included 3 It is highly probable that the exploration wave TW will be reflected by the site (A2_1, A2_2 and A2_3 in the figure). On the other hand, in this case, when the pedestrian is in the second state, it is highly probable that the exploration wave TW is mainly reflected by one part (A2_1 in the figure) including the left arm.

In this way, when the object O is a pedestrian, the number of parts that mainly reflect the exploration wave TW in the pedestrian varies depending on the irradiation timing of the exploration wave TW on the pedestrian. In addition, the number of the parts varies depending on the irradiation direction of the exploration wave TW to the pedestrian. Therefore, the number of the parts varies depending on the direction of reflection of the exploration wave TW by the pedestrian.

FIG. 6 shows an example of the first echo group EG1 and the second echo group EG2 when the object O is a pedestrian.

As shown in FIG. 6, first, when the sonar 2_OR transmits the exploration wave TW1, the sonar 2_OR receives the first reflected wave RW1, the reception control unit 21 acquires the first reception signal RS1, and echo detection is performed. It is assumed that the unit 22 has detected the first echo group EG1. The exploration wave TW1 and the first reflected wave RW1 in this case have a direct wave relationship. Next, when another sonar 2_OL transmits the exploration wave TW2, the sonar 2_OL receives the second reflected wave RW2, the reception control unit 21 acquires the second reception signal RS2, and the echo detection unit 22 receives the second reception signal RS2. 2 It is assumed that the echo group EG2 is detected. The exploration wave TW2 and the second reflected wave RW2 in this case have a direct wave relationship.

In the example shown in FIG. 6, the first echo group EG1 includes two echoes E_1 and E_2. That is, the first echo group EG1 includes a forest-like echo. This is because, for example, the exploration wave TW1 is reflected mainly by the torso and one arm, and the first reflected wave RW1 is received by the sonar 2_OR.

On the other hand, the second echo group EG2 contains three echoes E_3, E_4, E_5. That is, the second echo group EG2 includes a forest-like echo. This is because, for example, the exploration wave TW2 is reflected mainly by the torso and both arms, and the second reflected wave RW2 is received by the sonar 2_OL.

FIG. 7 shows other examples such as the first echo group EG1 and the second echo group EG2 when the object O is a pedestrian.

As shown in FIG. 7, when the sonar 2_OR transmits the exploration wave TW1, the sonar 2_OR receives the first reflected wave RW1, the reception control unit 21 acquires the first reception signal RS1, and the echo detection unit 22. Detected the first echo group EG1. The exploration wave TW1 and the first reflected wave RW1 in this case have a direct wave relationship. Further, at this time, another sonar 2_OL receives the second reflected wave RW2, the reception control unit 21 acquires the second reception signal RS2, and the echo detection unit 22 detects the second echo group EG2. To do. The exploration wave TW1 and the second reflected wave RW2 in this case have an indirect wave relationship.

In the example shown in FIG. 7, the first echo group EG1 includes two echoes E_1 and E_2. That is, the first echo group EG1 includes a forest-like echo. This is because, for example, the first reflected wave RW1 is mainly related to the reflection by the body and one arm.

On the other hand, the second echo group EG2 contains one echo E_3. That is, the second echo group EG2 includes a plate-shaped echo. This is because, for example, the second reflected wave RW2 is mainly related to the reflection by the body.

In this way, when the object O is a pedestrian, individual echoes are made according to the irradiation timing of the exploration wave TW on the pedestrian, the irradiation direction of the exploration wave TW on the pedestrian, and the reflection direction of the exploration wave TW by the pedestrian. The number of echoes NE in the group EG fluctuates. This is because, as explained with reference to FIG. 5, the number of parts that mainly reflect the exploration wave TW in the pedestrian fluctuates.

Based on the above contents, the first pedestrian discrimination unit 23 determines whether or not the object O is a pedestrian as follows. More specifically, the first pedestrian discrimination unit 23 determines whether the object O is a pedestrian or a stationary object.

That is, the first pedestrian discrimination unit 23 calculates the number of echoes in the first echo group EG1 (hereinafter referred to as “first echo number”) NE1 and the number of echoes in the second echo group EG2 (hereinafter referred to as “second echo”). It is called "number".) NE2 is calculated. The first pedestrian discrimination unit 23 determines that the object O is a pedestrian when at least one of the first echo number NE1 and the second echo number NE2 is 2 or more. On the other hand, when the first echo number NE1 is 1 and the second echo number NE2 is 1, the first pedestrian determination unit 23 determines that the object O is a stationary object.

Alternatively, the first pedestrian discrimination unit 23 calculates the first echo number NE1 and the second echo number NE2. The first pedestrian discrimination unit 23 determines that the object O is a pedestrian when the total number of the first echo number NE1 and the second echo number NE2 is 3 or more. On the other hand, when the total number of the first echo number NE1 and the second echo number NE2 is 2, the first pedestrian determination unit 23 determines that the object O is a stationary object.

In other words, the first pedestrian discrimination unit 23 determines that the object O is a pedestrian when at least one of the first echo group EG1 and the second echo group EG2 includes a plurality of echoes E. .. On the other hand, when the first echo group EG1 contains only one echo E and the second echo group EG2 contains only one echo E, the first pedestrian discrimination unit 23 is the object O. Is determined to be a stationary object.

For example, in the example shown in FIG. 3, the first echo number NE1 is 1 and the second echo number NE2 is 1. Therefore, the first pedestrian discrimination unit 23 determines that the object O is a stationary object. Further, in the example shown in FIG. 4, the first echo number NE1 is 1 and the second echo number NE2 is 1. Therefore, the first pedestrian discrimination unit 23 determines that the object O is a stationary object. Further, in the example shown in FIG. 6, the first echo number NE1 is 2 and the second echo number NE2 is 3. Therefore, the first pedestrian discrimination unit 23 determines that the object O is a pedestrian. Further, in the example shown in FIG. 7, the first echo number NE1 is 2 and the second echo number NE2 is 1. Therefore, the first pedestrian discrimination unit 23 determines that the object O is a pedestrian.

Suppose that it is determined whether the object O is a pedestrian or a stationary object based only on the echo group EG corresponding to the reflected wave RW in one direction by the object O. In this case, for example, in the example shown in FIG. 7, the object O is stationary even though the object O is a pedestrian, based on the plate-shaped echo included in the second echo group EG2 corresponding to the second reflected wave RW2. It may be misidentified as a thing. On the other hand, the first pedestrian discrimination unit 23 determines whether the object O is a pedestrian or a stationary object based on the echo groups EG1 and EG2 corresponding to the reflected waves RW1 and RW2 in a plurality of directions by the object O. Determine. Thereby, for example, in the example shown in FIG. 7, it is possible to accurately determine that the object O is a pedestrian.

In this way, by using the reflected waves RW1 and RW2 in a plurality of directions, it is possible to improve the accuracy of determining whether or not the object O is a pedestrian, as compared with the case where only the reflected waves RW in one direction are used. it can.

Hereinafter, the processes executed by the first pedestrian discrimination unit 23 are collectively referred to as "pedestrian discrimination processing".

Next, the operation of the body discriminating unit 24 will be described with reference to FIG.

When the object O is determined to be a pedestrian by the first pedestrian discrimination unit 23, each of the first echo group EG1 and the second echo group EG2 contains one or more echoes E. At this time, the body discrimination unit 24 determines which of the one or more echoes E echoes corresponds to the body. More specifically, the body discriminating unit 24 discriminates the echo E corresponding to the body by the following first discriminating method, second discriminating method, third discriminating method or fourth discriminating method.

<First discrimination method (see FIG. 8A)>
The body discrimination unit 24 calculates the number of echoes NE in each echo group EG. In addition, the body discrimination unit 24 calculates the width (hereinafter referred to as "echo width") EW of the portion exceeding the threshold Th1 in each echo E. When the number of echoes NE is 1, and the echo width EW of the one echo E is equal to or larger than a predetermined width, the body discriminating unit 24 determines that the one echo E corresponds to the body. To do.

Normally, when the area of the portion that reflects the exploration wave TW (hereinafter referred to as "reflection area") is large, the echo width EW of the corresponding echo E becomes larger than when the reflection area is small. In other words, when the reflection area is small, the echo width EW of the corresponding echo E is smaller than when the reflection area is large. Here, when the exploration wave TW is reflected by the body, the reflection area tends to be larger than when the exploration wave TW is reflected by the left arm or the right arm. On the other hand, when the exploration wave TW is reflected by the left arm or the right arm, the reflection area tends to be smaller than when the exploration wave TW is reflected by the body. Therefore, the body discriminating unit 24 discriminates the echo E corresponding to the body based on the magnitude of the echo width EW.

In the example shown in FIG. 8A, one echo E_1 is detected. The fuselage discrimination unit 24 calculates that the number of echoes NE is 1, and also calculates one echo width EW_1 corresponding to the one echo E_1. Since the one echo width EW_1 is equal to or larger than the predetermined width, the body discrimination unit 24 determines that the one echo E_1 corresponds to the body.

<Second discrimination method (see FIG. 8B)>
The body discrimination unit 24 calculates the number of echoes NE in each echo group EG. Further, the body discriminating unit 24 calculates the echo width EW of each echo E. When the number of echoes NE is 2 or more, the body discrimination unit 24 determines that the echo E having the maximum echo width EW among the two or more echoes E corresponds to the body.

That is, as described above, when the exploration wave TW is reflected by the body, the reflection area tends to be larger than when the exploration wave TW is reflected by the left arm or the right arm. On the other hand, when the exploration wave TW is reflected by the left arm or the right arm, the reflection area tends to be smaller than when the exploration wave TW is reflected by the body. Therefore, the body discriminating unit 24 discriminates the echo E corresponding to the body based on the magnitude of the echo width EW.

In the example shown in FIG. 8B, two echoes E_1 and E_2 are detected. The fuselage discriminating unit 24 calculates that the number of echoes NE is 2, and also calculates two echo widths EW_1 and EW_2 corresponding to the two echoes E_1 and E_2. Since the echo width EW_1 is larger than the echo width EW_2, the body discrimination unit 24 determines that the echo E_1 corresponds to the body.

<Third discrimination method (see FIG. 8C)>
The body discrimination unit 24 calculates the number of echoes NE in each echo group EG. When the number of echoes NE is 3 or more, the body discriminating unit 24 has the remaining echoes E excluding the echoes E arranged at both ends in the window W among the three or more echoes E corresponding to the body. It is determined that. In other words, the body discriminating unit 24 determines that the echo E arranged in the central portion in the window W of the three or more echoes E corresponds to the body.

For example, when the exploration wave TW is reflected by the left arm, the torso and the right arm, usually, the exploration wave TW is first reflected by either the left arm or the right arm, and then the exploration wave TW is reflected by the fuselage. Then, it is highly probable that the exploration wave TW is reflected by either the left arm or the right arm. Therefore, the body discriminating unit 24 discriminates the echo E corresponding to the body based on the arrangement position in the window W.

In the example shown in FIG. 8C, three echoes E_1, E_2, and E_3 are detected. The fuselage discrimination unit 24 calculates that the echo number NE is 3. The body discriminating unit 24 determines that the remaining echoes E_2 excluding the echoes E_1 and E_3 arranged at both ends in the window W of the three echoes E_1, E_2, and E_3 correspond to the fuselage. .. That is, the body discriminating unit 24 determines that the echo E_2 arranged in the central portion in the window W of the three echoes E_1, E_2, and E_3 corresponds to the fuselage.

<Fourth discrimination method (see FIG. 8D)>
The body discriminating unit 24 calculates the number of echoes NE in each echo group EG. Further, the body discriminating unit 24 calculates the peak value (hereinafter referred to as “actual peak value”) P of each echo E. Further, the body discriminating unit 24 calculates the echo width EW of each echo E, and calculates the peak value (hereinafter referred to as “estimated peak value”) P'based on the calculated echo width EW. Specifically, for example, the body discriminating unit 24 calculates the estimated peak value P'by multiplying the calculated echo width EW by a predetermined coefficient α. The fuselage discrimination unit 24 calculates the difference value ΔP between the actual peak value P and the estimated peak value P'for each echo E. When the number of echoes NE is 2 or more, the body discrimination unit 24 determines that the echo E having the maximum difference value ΔP among the two or more echoes E corresponds to the body. As a specific example of the predetermined coefficient α, a coefficient that is similar to the transmission signal is selected.

That is, when the difference value ΔP is large, the corresponding echo E waveform is a waveform in which the echo width EW is larger than the actual peak value P. This indicates that the reflection area is large (see the description of the first determination method). When the exploration wave enters an object with a large reflection area, the number of propagation paths reflected by the object and received again increases, and the propagation path lengths differ slightly. Therefore, each reflected wave that has propagated through these plurality of propagation paths and returned is received with a slight delay, and thus becomes a composite wave of these reflected waves. The echo width of the composite wave becomes large, but the peak itself does not become large because it does not have a similar waveform to the exploration wave. On the other hand, when the difference value ΔP is small, the corresponding echo E waveform is a waveform in which the echo width EW is smaller than the actual peak value P. This indicates that the reflection area is small (see the description of the first determination method). When an exploration wave is incident on an object with a small reflection area, the number of propagation paths reflected by the object and received again is smaller than that of an object with a large reflection area. Therefore, the number of reflected waves to be combined is also reduced, so that the synthesized wave has a waveform close to the similar waveform of the exploration wave. The echo width of the composite wave is smaller than that of an object with a large reflection area. Therefore, the body discriminating unit 24 discriminates the echo E corresponding to the body based on the magnitude of the difference value ΔP.

In the example shown in FIG. 8D, two echoes E_1 and E_2 are detected. The fuselage discrimination unit 24 calculates that the echo number NE is 2. The fuselage discrimination unit 24 calculates the actual peak value P_1 for the echo E_1, calculates the echo width EW_1, calculates the estimated peak value P'_1, and calculates the difference value ΔP_1. The fuselage discrimination unit 24 calculates the actual peak value P_2 for the echo E_2, calculates the echo width EW_2, calculates the estimated peak value P'_2, and calculates the difference value ΔP_2. Since the difference value ΔP_2 is larger than the difference value ΔP_1, the body discriminating unit 24 determines that the echo E_2 corresponds to the body.

Hereinafter, the processes executed by the body discrimination unit 24 are collectively referred to as "body discrimination process".

Next, the operation of the position calculation unit 13 will be described. At the same time, the operation of the vehicle information acquisition unit 12 will be described.

The vehicle information acquisition unit 12 uses the sensors 5 to acquire information indicating the position coordinates of the vehicle 1 when the exploration wave TW is transmitted by each sonar 2. Further, the position calculation unit 13 acquires information indicating the distance D calculated by the reception control unit 21. The position calculation unit 13 calculates the position of the object O by using this information. More specifically, the position calculation unit 13 has a position coordinate PC of the object O in the coordinate system CS1 having an X axis corresponding to the left-right direction of the vehicle 1 and a Y axis corresponding to the front-rear direction of the vehicle 1. Is calculated. Various known calculation methods can be used for the calculation of the position coordinate PC. The description of these calculation methods will be omitted.

Here, when the discrimination result by the first pedestrian discrimination unit 23 indicates a pedestrian, the position calculation unit 13 acquires the discrimination result by the body discrimination unit 24. The position calculation unit 13 calculates the position coordinate PC of the body based on the determination result by the body determination unit 24. That is, in this case, the reception control unit 21 calculates, for example, the distance D corresponding to the left arm, the distance D corresponding to the torso, and the distance D corresponding to the right arm. The position calculation unit 13 calculates the position coordinate PC based on the distance D corresponding to the body of the calculated distance D.

Hereinafter, the processes executed by the position calculation unit 13 are collectively referred to as "position calculation process".

Next, the operations of the warning necessity determination unit 14 and the warning signal output unit 15 will be described with reference to FIGS. 9 to 11. At the same time, the operations of the vehicle information acquisition unit 12 and the output device 6 will be described.

The vehicle information acquisition unit 12 uses the sensors 5 to acquire information indicating the position coordinates of the vehicle 1 and information indicating the traveling direction of the vehicle 1. The warning necessity determination unit 14 calculates the predicted course PP of the vehicle 1 by using this information. The warning necessity determination unit 14 sets a range (hereinafter referred to as “predicted course range”) A3 corresponding to the calculated predicted course PP. The predicted course range A3 is, for example, a range in the coordinate system CS1. The warning necessity determination unit 14 determines whether the object O is located within the predicted course range A3 or outside the predicted course range A3 based on the position coordinate PC calculated by the position calculation unit 13. judge.

The warning necessity determination unit 14 acquires the determination result by the first pedestrian determination unit 23. When the warning necessity determination unit 14 determines that the object O is located within the predicted course range A3 (see FIG. 9), the warning necessity determination unit 14 of the vehicle 1 regardless of the determination result by the first pedestrian determination unit 23. It is determined that a warning to passengers (hereinafter simply referred to as "warning") is necessary.

Further, when the warning necessity determination unit 14 determines that the object O is located outside the predicted course range A3 (see FIG. 10), the determination result by the first pedestrian determination unit 23 determines the pedestrian. When indicated, determine that a warning is required. Further, in this case, the warning necessity determination unit 14 determines that the warning is unnecessary when the determination result by the first pedestrian determination unit 23 indicates a stationary object. FIG. 11 shows a table T used for these determination processes.

When the warning signal output unit 15 determines that a warning is required by the warning necessity determination unit 14, the warning signal output unit 15 outputs a warning signal (hereinafter referred to as “warning signal”) to the output device 6 and the vehicle control device (not shown). Or output to at least one of the wireless communication devices (not shown). The vehicle control device is composed of, for example, an ECU. The wireless communication device is composed of, for example, a transmitter and a receiver for wireless communication.

The display in the output device 6 displays a warning image when the warning signal is output by the warning signal output unit 15. The speaker in the output device 6 outputs a warning voice when the warning signal is output by the warning signal output unit 15. As a result, it is possible to notify the passenger of the vehicle 1 that the vehicle 1 may collide with the object O.

When the warning signal is output by the warning signal output unit 15, the vehicle control device executes control for collision damage mitigation by controlling the brake and engine torque of the vehicle 1. As a result, it is possible to reduce the damage when the vehicle 1 collides with the object O. Alternatively, when the warning signal is output by the warning signal output unit 15, the vehicle control device executes collision avoidance control by controlling the brake, engine torque, steering, and the like of the vehicle 1. As a result, it is possible to avoid a collision between the vehicle 1 and the object O.

When the warning signal is output by the warning signal output unit 15, the wireless communication device notifies the mobile information terminal (not shown) or the server device (not shown) to that effect. As a result, it is possible to notify a person different from the passenger of the vehicle 1 that the vehicle 1 may collide with the object O.

Next, the hardware configuration of the main part of the control device 4 will be described with reference to FIG.

As shown in FIG. 12A, the control device 4 has a processor 31 and a memory 32. The memory 32 includes a transmission control unit 11, a vehicle information acquisition unit 12, a position calculation unit 13, a warning necessity determination unit 14, a warning signal output unit 15, a reception control unit 21, an echo detection unit 22, and a first pedestrian determination unit. A program for realizing the functions of the 23 and the body discriminating unit 24 is stored. When the processor 31 reads and executes such a program, the transmission control unit 11, the vehicle information acquisition unit 12, the position calculation unit 13, the warning necessity determination unit 14, the warning signal output unit 15, the reception control unit 21, and the echo detection unit 22, the functions of the first pedestrian discrimination unit 23 and the body discrimination unit 24 are realized.

Alternatively, as shown in FIG. 12B, the control device 4 has a processing circuit 33. In this case, the transmission control unit 11, the vehicle information acquisition unit 12, the position calculation unit 13, the warning necessity determination unit 14, the warning signal output unit 15, the reception control unit 21, the echo detection unit 22, the first pedestrian determination unit 23, and the like. The function of the body discriminating unit 24 is realized by a dedicated processing circuit 33.

Alternatively, the control device 4 has a processor 31, a memory 32, and a processing circuit 33 (not shown). In this case, the transmission control unit 11, the vehicle information acquisition unit 12, the position calculation unit 13, the warning necessity determination unit 14, the warning signal output unit 15, the reception control unit 21, the echo detection unit 22, the first pedestrian determination unit 23, and the like. Some of the functions of the body discriminating unit 24 are realized by the processor 31 and the memory 32, and the remaining functions are realized by the dedicated processing circuit 33.

The processor 31 is composed of one or a plurality of processors. As the individual processor, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a microprocessor, a microcontroller, or a DSP (Digital Signal Processor) is used.

The memory 32 is composed of one or a plurality of non-volatile memories. Alternatively, the memory 32 is composed of one or more non-volatile memories and one or more volatile memories. Each volatile memory uses, for example, a RAM (Random Access Memory). The individual non-volatile memories include, for example, a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Advanced Storage), a Small DriveSlide (Erasable Memory), and an EEPROM. Drive) is used.

The processing circuit 33 is composed of one or a plurality of digital circuits. Alternatively, the processing circuit 33 is composed of one or more digital circuits and one or more analog circuits. That is, the processing circuit 33 is composed of one or a plurality of processing circuits. The individual processing circuits include, for example, an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), an FPGA (Field-Programmable Gate Array), an FPGA (Field-Programmable Gate Array), and a System-System (System) System. ) Is used.

Next, with reference to the flowchart of FIG. 13, regarding the operation of the control device 4, the transmission control unit 11, the reception control unit 21, the echo detection unit 22, the first pedestrian discrimination unit 23, the body discrimination unit 24, and the position calculation unit The operation of 13 will be mainly described.

First, the transmission control unit 11 executes the exploration wave transmission control (step ST1). Next, the reception control unit 21 acquires the reception signal RS (step ST2). Next, the reception control unit 21 executes the object detection process and the distance measurement process (step ST3). Since the details of the exploration wave transmission control, the object detection process, and the distance measurement process have already been described with reference to FIG. 2, the description thereof will be omitted again.

If the object O is not detected by the object detection process (step ST4 “NO”), the process of the control device 4 proceeds to step ST1. On the other hand, when the object O is detected by the object detection process (step ST4 “YES”), the obstacle detection device 100 then detects the object O and the second received signal RS2 using the first received signal RS1. It is determined whether or not the object O detected by the use is the same object as each other (step ST5).

Specifically, for example, the obstacle detection device 100 determines whether or not these objects O are the same objects based on the distance D calculated by the distance measuring process. That is, the obstacle detection device 100 is the difference between the distance D corresponding to the object O detected by using the first received signal RS1 and the distance D corresponding to the object O detected by using the second received signal RS2. Calculate the value. When the calculated difference value is less than a predetermined value, the obstacle detection device 100 determines that these objects O are the same objects. On the other hand, when the calculated difference value is equal to or greater than a predetermined value, the obstacle detection device 100 determines that these objects O are different objects from each other.

When it is determined that these objects O are the same objects (step ST5 “YES”), the process of the control device 4 proceeds to step ST6. On the other hand, when it is determined that these objects O are different objects from each other (step ST5 “NO”), the process of the control device 4 proceeds to step ST1.

Next, the echo detection unit 22 executes the echo detection process (step ST6). Since the details of the echo detection process have already been described with reference to FIG. 2, the description thereof will be omitted again.

Next, the first pedestrian discrimination unit 23 executes the pedestrian discrimination process (step ST7). Since the details of the pedestrian discrimination process have already been described with reference to FIGS. 3 to 7, the description thereof will be omitted again.

When the discrimination result by the first pedestrian discrimination unit 23 indicates a pedestrian (step ST8 “YES”), then the body discrimination unit 24 executes the body discrimination process (step ST9). Since the details of the body discrimination process have already been described with reference to FIG. 8, the description will be omitted again. If the discrimination result by the first pedestrian discrimination unit 23 indicates a stationary object (step ST8 “NO”), the process of step ST9 is skipped.

Next, the position calculation unit 13 executes the position calculation process (step ST10). Since the details of the position calculation process have already been described, the description thereof will be omitted again.

Next, with reference to FIG. 14, the operation of the control device 4 will be described focusing on the operations of the warning necessity determination unit 14 and the warning signal output unit 15. The process of step ST11 shown in FIG. 14 is executed, for example, after the process of step ST10 shown in FIG.

First, the warning necessity determination unit 14 determines the necessity of warning (step ST11). Since the details of the determination method by the warning necessity determination unit 14 have already been described with reference to FIGS. 9 to 11, the description will be omitted again.

When the warning necessity determination unit 14 determines that a warning is required (step ST12 “YES”), then the warning signal output unit 15 outputs a warning signal (step ST13). Since the details of the output destination of the warning signal have already been persuaded, the explanation will be omitted again. If the warning necessity determination unit 14 determines that the warning is unnecessary (step ST12 “NO”), the process of step ST13 is skipped.

The irradiation range A1 and the reflection range A2 when the object O is a pedestrian are not limited to the specific examples shown in FIG. For example, as shown in FIG. 15, the irradiation range A1 may include the road surface R.

As shown in FIG. 15, a pedestrian is referred to as a state in which both feet are in contact with the road surface R (hereinafter referred to as "fourth state") and a state in which only one foot is in contact with the road surface R (hereinafter referred to as "fifth state"). ) And repeat. When the exploration wave TW is irradiated in the fourth state, so-called "regression reflection" occurs in each of the left foot and the right foot. Therefore, the reflected wave RW by two parts (A2_1 and A2_2 in the figure) including the left foot and the right foot is received. On the other hand, when the exploration wave TW is irradiated in the fifth state, regression reflection occurs in either the left foot or the right foot. Therefore, the reflected wave RW by one part (A2_1 in the figure) including the left foot or the right foot is received.

Here, the regression reflection means that the exploration wave TW is first reflected by the road surface R and then reflected by the shoes of a pedestrian. Alternatively, the regression reflection means that the exploration wave TW is first reflected by the pedestrian's shoes and then by the road surface R.

In this way, the number of parts that mainly reflect the exploration wave TW in the pedestrian varies depending on the irradiation timing of the exploration wave TW on the pedestrian. Therefore, it is possible to determine whether or not the object O is a pedestrian by the pedestrian discrimination process in the first pedestrian discrimination unit 23.

In particular, depending on the material of the clothes worn by pedestrians, the reflectance of the exploration wave TW by the body may be low. In contrast, such materials are rarely used in shoes. When the road surface R is included in the irradiation range A1, the pedestrian can be reliably detected based on the reflected wave RW due to the retroreflective even when the pedestrian is wearing clothes having low reflectance. it can.

Next, a modified example of the obstacle detection system 200 will be described.

The control device 4 may repeatedly execute the process shown in FIG. 13 when the vehicle 1 is moving backward. As a result, the control device 4 may execute a so-called "tracking" process for each object O. The control device 4 may calculate the TTC (Time To Collision) related to each object O based on the tracking result. For example, the mode or content of the warning output by the output device 6 may change according to the calculated TTC, or the output timing of the warning by the output device 6 may change. good.

Further, as described above, the first reflected wave RW1 may be a direct wave and the second reflected wave RW2 may be a direct wave (see FIG. 3 or FIG. 6). Further, the first reflected wave RW1 may be a direct wave and the second reflected wave RW2 may be an indirect wave (see FIG. 4 or 7). On the other hand, the first reflected wave RW1 may be an indirect wave and the second reflected wave RW2 may be a direct wave (not shown). Further, the first reflected wave RW1 may be an indirect wave and the second reflected wave RW2 may be an indirect wave (not shown).

However, when only the direct wave is used, it is required to transmit the exploration wave TW at least twice before the pedestrian discrimination process is executed. On the other hand, when the indirect wave is used, it is required to transmit the exploration wave TW at least once before the pedestrian discrimination process is executed. That is, by using the indirect wave, the pedestrian discrimination process can be executed earlier than in the case of using only the direct wave. Therefore, it is more preferable to use an indirect wave.

Further, one sonar 2 may be provided at the rear end of the vehicle 1 instead of the N sonars 2. That is, the rear sonar 3 may be configured by the one sonar 2. In this case, the first reflected wave RW1 and the second reflected wave RW2 may be received by the one sonar 2 transmitting the exploration wave TW a plurality of times while the vehicle 1 is reversing.

Further, N sonars 2 may be provided at the front end of the vehicle 1. That is, the front sonar may be composed of the N sonars 2. In this case, the process shown in FIG. 13 may be executed when the vehicle 1 is moving forward. The object detection process in this case detects the object O existing in front of the vehicle 1.

Further, one sonar 2 may be provided at the front end of the vehicle 1. That is, the front sonar may be provided by the one sonar 2. In this case, even if the first reflected wave RW1 and the second reflected wave RW2 are received by the one sonar 2 transmitting the exploration wave TW a plurality of times when the vehicle 1 is moving forward. good.

Further, instead of N sonars 2, one or more riders or one or more radars may be provided. That is, the exploration wave TW is not limited to ultrasonic waves, but may be radio waves or light. However, it is more preferable to use ultrasonic waves from the viewpoint of suppressing the occurrence of interference of the exploration wave TW between the vehicle 1 and the vehicle in front or the vehicle behind the vehicle 1.

As described above, the obstacle detection device 100 differs from the first received signal RS1 corresponding to the first reflected wave RW1 reflected by the object O existing around the vehicle 1 and the first reflected wave RW1 depending on the object O. The reception control unit 21 that acquires the received signal RS including the second received signal RS2 corresponding to the second reflected wave RW2 reflected in the direction, the first echo group EG1 in the first received signal RS1, and the second reception. A plurality of echoes in a window W having a width corresponding to a pedestrian based on the detection results of the echo detection unit 22 for detecting the second echo group EG2 including the second echo group EG2 in the signal RS2 and the echo detection unit 22. A first pedestrian discrimination unit 23 that determines that the object O is a pedestrian and outputs the result of the determination when E is present is provided. Thereby, it is possible to determine whether or not the object O is a pedestrian. In particular, by using the reflected waves RW1 and RW2 in a plurality of directions, it is possible to improve the accuracy of determining whether or not the object O is a pedestrian, as compared with the case where only the reflected waves RW in one direction are used.

Further, the obstacle detection device 100 is a body discrimination unit that discriminates the echo E corresponding to the pedestrian's body among the plurality of echoes E based on the number of echoes NE in the echo group EG or the echo width EW in the echo group EG. 24 is provided. Thereby, when the object O is a pedestrian, the echo E corresponding to the torso can be discriminated. As a result, for example, when the object O is a pedestrian, the position coordinate PC of the object O can be accurately calculated.

Further, in the body discriminating unit 24, when the number of echoes NE is 3 or more, the echo E arranged in the central portion excluding the echo E arranged at both ends in the window W among the plurality of echoes E is the fuselage. It is determined that the echo E corresponds to. In this way, the echo E corresponding to the body can be discriminated by the third discriminating method (see FIG. 8C).

Further, the body discrimination unit 24 determines that the echo E having the maximum echo width EW among the plurality of echoes E is the echo E corresponding to the body. In this way, the echo E corresponding to the body can be discriminated by the second discriminating method (see FIG. 8B).

Further, the body discriminating unit 24 calculates a difference value ΔP between the actual peak value P and the estimated peak value P'based on the echo width EW for each of the plurality of echoes E, and among the plurality of echoes E. It is determined that the echo E having the maximum difference value ΔP is the echo E corresponding to the fuselage. In this way, the echo E corresponding to the body can be discriminated by the fourth discriminating method (see FIG. 8D).

Further, the reflected wave RW including the first reflected wave RW1 and the second reflected wave RW2 is received by a plurality of sonars 2 provided at different positions in the vehicle 1. For example, the first reflected wave RW1 is received by the sonar 2_OR, and the second reflected wave RW2 is received by another sonar 2_OL (see FIGS. 3, 4, 6 and 7). ). By using a plurality of sonars 2, it is possible to receive reflected waves RW1 and RW2 having different reflection directions by the object O.

In addition, the rear sonar 3 is composed of a plurality of sonars 2. By using the rear sonar 3, it is possible to detect the object O existing behind the vehicle 1.

Further, the road surface R is included in the irradiation range A1 of the exploration wave TW by the plurality of sonars 2. As a result, when the object O is a pedestrian, the pedestrian can be reliably detected regardless of the material of the clothes worn by the pedestrian (see FIG. 15).

Embodiment 2.
FIG. 16 is a block diagram showing a main part of an obstacle detection system including the obstacle detection device according to the second embodiment. An obstacle detection system including the obstacle detection device according to the second embodiment will be described with reference to FIG. In FIG. 16, the same blocks as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 16, the control device 4a has a second pedestrian discrimination unit 25. In the second pedestrian discrimination unit 25, when the first echo group EG1 and the second echo group EG2 are detected by the echo detection unit 22, the object O is subjected to a discrimination method different from the discrimination method by the first pedestrian discrimination unit 23. Determine if you are a pedestrian. More specifically, the second pedestrian discrimination unit 25 discriminates whether the object O is a pedestrian or a stationary object as follows.

That is, the second pedestrian discrimination unit 25 calculates the similarity DS between the first echo group EG1 and the second echo group EG2. The second pedestrian discrimination unit 25 determines that the object O is a stationary object when the calculated similarity DS is equal to or higher than a predetermined value. On the other hand, when the calculated similarity DS is less than a predetermined value, the second pedestrian determination unit 25 determines that the object O is a pedestrian.

As described in the first embodiment, when the object O is a stationary object (for example, one pole), the first echo number NE1 becomes equal to the second echo number NE2. Further, in this case, it is highly probable that the shape of the portion related to the reflection of the first reflected wave RW1 in the object O is the same as the shape of the portion related to the reflection of the second reflected wave RW2. Further, in this case, it is highly probable that the material of the portion related to the reflection of the first reflected wave RW1 is the same as the material of the portion related to the reflection of the second reflected wave RW2.

On the other hand, when the object O is a pedestrian, the first echo number NE1 may be different from the second echo number NE2 as described in the first embodiment. Further, in this case, the shape of the portion related to the reflection of the first reflected wave RW1 (for example, one portion including the left arm) is changed to the portion related to the reflection of the second reflected wave RW2 (for example, the left arm, depending on the posture of the pedestrian). There is a high probability that it will be different from the shape of the body) and the right arm). Further, in this case, the material of the part related to the reflection of the first reflected wave RW1 (for example, cloth) is the material of the part related to the reflection of the second reflected wave RW2 (for example, cloth and skin) according to the clothes of the pedestrian. Can be different.

Therefore, when the object O is a stationary object, the similarity DS tends to be higher than when the object O is a pedestrian. On the other hand, when the object O is a pedestrian, the similarity DS tends to be lower than when the object O is a stationary object. Therefore, the second pedestrian discrimination unit 25 determines whether the object O is a pedestrian or a stationary object based on the level of the similarity DS. Hereinafter, a specific example of the calculation method of the similarity DS will be described.

<First specific example of the calculation method of similarity DS>
The second pedestrian discrimination unit 25 calculates the correlation function between the first echo group EG1 and the second echo group EG2. The second pedestrian discrimination unit 25 calculates the similarity DS based on the calculated correlation function.

<Second specific example of the calculation method of similarity DS>
The second pedestrian discrimination unit 25 detects the waveform area (hereinafter referred to as “first area”) S1 in the first echo group EG1. The first area S1 is, for example, the total value of the areas of the portions where the intensity in the first echo group EG1 exceeds the threshold Th1. Further, the second pedestrian discrimination unit 25 calculates the waveform area (hereinafter referred to as “second area”) S2 in the second echo group EG2. The second area S2 is, for example, the total value of the areas of the portions where the intensity in the second echo group EG2 exceeds the threshold Th1.

The second pedestrian discrimination unit 25 calculates the difference value between the first area S1 and the second area S2. The second pedestrian discrimination unit 25 calculates the similarity DS based on the calculated difference value.

<Third specific example of the calculation method of similarity DS>
The second pedestrian discrimination unit 25 calculates the peak value (hereinafter referred to as “first peak value”) in the first echo group EG1. The first peak value is, for example, the actual peak value P of the one echo E when the first echo group EG1 includes one echo E. Or, for example, when the first echo group EG1 includes two or more echoes E, the first peak value is the maximum value, the minimum value, the average value, or the center of the actual peak value P of the two or more echoes E. The value.

Further, the second pedestrian discrimination unit 25 calculates the peak value (hereinafter referred to as "second peak value") in the second echo group EG2. The second peak value is, for example, the actual peak value P of the one echo E when the second echo group EG2 includes one echo E. Or, for example, when the second echo group EG2 includes two or more echoes E, the second peak value is the maximum value, the minimum value, the average value, or the median of the actual peak value P of the two or more echoes E. The value.

The second pedestrian discrimination unit 25 calculates the difference value between the first peak value and the second peak value. The second pedestrian discrimination unit 25 calculates the similarity DS based on the calculated difference value.

<Fourth specific example of the calculation method of similarity DS>
The second pedestrian discrimination unit 25 calculates the similarity DS by using the determination result signal RS'corresponding to each of the first reception signal RS1 and the first reception signal RS1.

Specifically, for example, the second pedestrian discrimination unit 25 has a portion in the window W of the determination result signal RS'corresponding to the first reception signal RS1 and a determination result signal corresponding to the second reception signal RS2. The correlation function with the part in the window W of RS'is calculated. The second pedestrian discrimination unit 25 calculates the similarity DS based on the calculated correlation function by the same calculation method as in the first specific example.

Alternatively, for example, the second pedestrian discrimination unit 25 indicates a portion (“High” in the figure) indicating that the object O in the determination result signal RS ′ corresponding to the first reception signal RS1 is detected. The waveform area in the object detection unit of the determination result signal RS'corresponding to the second reception signal RS2 is calculated. The second pedestrian discrimination unit 25 calculates the similarity DS based on these waveform areas by the same calculation method as in the second specific example.

Transmission control unit 11, vehicle information acquisition unit 12, position calculation unit 13, warning necessity determination unit 14, warning signal output unit 15, reception control unit 21, echo detection unit 22, first pedestrian discrimination unit 23, fuselage discrimination unit The main part of the control device 4a is composed of the 24 and the second pedestrian discrimination unit 25. Further, the reception control unit 21, the echo detection unit 22, the first pedestrian discrimination unit 23, the body discrimination unit 24, and the second pedestrian discrimination unit 25 constitute a main part of the obstacle detection device 100a.

In this way, the main part of the obstacle detection system 200a is configured.

Since the hardware configuration of the main part of the control device 4a is the same as that described with reference to FIG. 12 in the first embodiment, the illustration and description will be omitted. That is, the transmission control unit 11, the vehicle information acquisition unit 12, the position calculation unit 13, the warning necessity determination unit 14, the warning signal output unit 15, the reception control unit 21, the echo detection unit 22, the first pedestrian determination unit 23, and the fuselage. The functions of the discriminating unit 24 and the second pedestrian discriminating unit 25 may be realized by, for example, the processor 31 and the memory 32, or may be realized by the dedicated processing circuit 33.

In the obstacle detection system 200a, the discrimination result by the second pedestrian discrimination unit 25 is used with priority over the discrimination result by the first pedestrian discrimination unit 23. For example, when the discrimination result by the first pedestrian discrimination unit 23 indicates a pedestrian and the discrimination result by the second pedestrian discrimination unit 25 indicates a stationary object, the body discrimination unit 24 and the position calculation unit 13 In the warning necessity determination unit 14 and the like, the object O is regarded as a stationary object. Alternatively, for example, when the discrimination result by the first pedestrian discrimination unit 23 indicates a stationary object and the discrimination result by the second pedestrian discrimination unit 25 indicates a pedestrian, the body discrimination unit 24, the position calculation In the unit 13 and the warning necessity determination unit 14, the object O is regarded as a pedestrian.

That is, it can be said that the second pedestrian discrimination unit 25 confirms the discrimination result by the first pedestrian discrimination unit 23. Hereinafter, in the second embodiment, the processes executed by the second pedestrian discrimination unit 25 are collectively referred to as "discrimination result confirmation process".

Next, with reference to the flowchart of FIG. 17, regarding the operation of the control device 4a, the transmission control unit 11, the reception control unit 21, the echo detection unit 22, the first pedestrian discrimination unit 23, the second pedestrian discrimination unit 25, The operations of the body determination unit 24 and the position calculation unit 13 will be mainly described. In FIG. 17, the same reference numerals are given to the same steps as those shown in FIG. 13, and the description thereof will be omitted.

First, the processes of steps ST1 to ST7 are executed. Since the processing contents of steps ST1 to ST7 are the same as those described with reference to the flowchart of FIG. 13 in the first embodiment, the description thereof will be omitted again.

Next, the second pedestrian discrimination unit 25 executes the discrimination result confirmation process (step ST21). Since the details of the determination result confirmation process have already been described, the description thereof will be omitted again.

Next, the processes of steps ST8 to ST10 are executed. Since the processing contents of steps ST8 to ST10 are the same as those described with reference to the flowchart of FIG. 13 in the first embodiment, the description thereof will be omitted again.

However, when the discrimination result by the first pedestrian discrimination unit 23 indicates a pedestrian and the discrimination result by the second pedestrian discrimination unit 25 indicates a stationary object, step ST8 “NO” is set. On the other hand, in this case, when the discrimination result by the second pedestrian discrimination unit 25 indicates a pedestrian, step ST8 “YES” is set.

Further, when the discrimination result by the first pedestrian discrimination unit 23 indicates a stationary object and the discrimination result by the second pedestrian discrimination unit 25 indicates a pedestrian, step ST8 “YES” is set. On the other hand, in this case, when the discrimination result by the second pedestrian discrimination unit 25 indicates a stationary object, step ST8 “NO” is set.

Next, a modified example of the obstacle detection system 200a will be described.

The control device 4a may repeatedly execute the process shown in FIG. 17 when the vehicle 1 is moving backward. In this case, the similarity DS is calculated a plurality of times by executing the process shown in FIG. 17 a plurality of times (step ST21). The second pedestrian discrimination unit 25 may use these similarity DSs to calculate the fluctuation amount ΔDS of the similarity DS with respect to time. The second pedestrian discrimination unit 25 may discriminate whether the object O is a pedestrian or a stationary object based on the calculated fluctuation amount ΔDS.

That is, when the object O is a stationary object, the fluctuation amount ΔDS tends to be smaller than when the object O is a pedestrian. This is because the shape and material of the portion that mainly reflects the exploration wave TW do not change with time. On the other hand, when the object O is a pedestrian, the fluctuation amount ΔDS tends to be larger than when the object O is a stationary object. This is because the shape and material of the portion that mainly reflects the exploration wave TW can fluctuate with time.

Therefore, the second pedestrian discrimination unit 25 determines that the object O is a pedestrian when the fluctuation amount ΔDS is equal to or greater than a predetermined threshold value Th2. On the other hand, when the fluctuation amount ΔDS is less than the threshold value Th2, the second pedestrian discrimination unit 25 determines that the object O is a stationary object. The threshold Th2 may be set by using a so-called "machine learning" technique.

Further, the use of the discrimination result by the second pedestrian discrimination unit 25 is not limited to the confirmation of the discrimination result by the first pedestrian discrimination unit 23. For example, in the obstacle detection device 100a, when at least one of the discrimination result by the first pedestrian discrimination unit 23 and the discrimination result by the second pedestrian discrimination unit 25 indicates a pedestrian, the object O is a pedestrian. It may be determined to be present. Further, in the obstacle detection device 100a, when the discrimination result by the first pedestrian discrimination unit 23 indicates a stationary object and the discrimination result by the second pedestrian discrimination unit 25 indicates a stationary object, the object O May be determined to be a stationary object.

Further, the obstacle detection device 100a may not have the first pedestrian determination unit 23. In this case, the discrimination result by the second pedestrian discrimination unit 25 may be used instead of the discrimination result by the first pedestrian discrimination unit 23.

In addition, the obstacle detection system 200a can employ various modifications similar to those described in the first embodiment.

As described above, the obstacle detection device 100a determines whether or not the object O is a pedestrian based on the similarity DS between the first echo group EG1 and the second echo group EG2, and the result of the determination is A second pedestrian discriminating unit 25 for outputting Thereby, for example, the discrimination result by the first pedestrian discrimination unit 23 can be confirmed. As a result, the accuracy of determining whether or not the object O is a pedestrian can be further improved.

Embodiment 3.
FIG. 18 is a block diagram showing a main part of an obstacle detection system including the obstacle detection device according to the third embodiment. An obstacle detection system including the obstacle detection device according to the third embodiment will be described with reference to FIG. In FIG. 18, the same blocks as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 18, the control device 4b has a third pedestrian discrimination unit 26. In the third pedestrian discrimination unit 26, the exploration wave TW is transmitted M times or more (M is an integer of 2 or more), and the received signal RS is acquired M times, so that M first received signals RS1 And when M second received signals RS2 are acquired and M echo group EGs are detected M times, and M first echo group EG1 and M second echo group EG2 are detected, the first Whether or not the object O is a pedestrian is determined by a discrimination method different from the discrimination method by the pedestrian discrimination unit 23. More specifically, the third pedestrian discrimination unit 26 discriminates whether the object O is a pedestrian or a stationary object as follows.

That is, first, the third pedestrian discrimination unit 26 calculates the first echo number NE1 in each of the M first echo group EG1, and the second echo number NE2 in each of the M second echo group EG2. Is calculated. The third pedestrian discrimination unit 26 calculates the feature amount (hereinafter referred to as “first feature amount”) FV1 based on the number of echoes NE.

Specifically, for example, the third pedestrian discrimination unit 26 calculates the average value of these echo numbers NE. The third pedestrian discrimination unit 26 uses the calculated average value for the first feature amount FV1.

Further, the third pedestrian discrimination unit 26 calculates the echo width EW of each of the one or more echoes E in each of the M first echo group EG1, and also in each of the M second echo group EG2. The echo width EW of each of one or more echoes E is calculated. The third pedestrian discrimination unit 26 calculates the feature amount (hereinafter referred to as “second feature amount”) FV2 based on these echo widths EW. Further, the third pedestrian discrimination unit 26 calculates a value indicating the fluctuation amount ΔFV2 of the second feature amount FV2 with respect to time by executing the statistical processing for the calculated second feature amount FV2.

Specifically, for example, the third pedestrian discrimination unit 26 calculates the total value or the average value of the echo width EW in each echo group EG. The third pedestrian discrimination unit 26 calculates the dispersion value of these total values or the dispersion value of these average values. In this case, the calculated total value or average value is the second feature amount FV2. Further, the calculated variance value is a value indicating the fluctuation amount ΔFV2.

Next, the third pedestrian discrimination unit 26 compares the calculated value of the first feature amount FV1 with the threshold value Th3 corresponding to the value of the calculated fluctuation amount ΔFV2. The third pedestrian discrimination unit 26 determines that the object O is a pedestrian when the calculated value of the first feature amount FV1 is the threshold value Th3 or more. On the other hand, when the calculated value of the first feature amount FV1 is less than the threshold value Th3, the third pedestrian discrimination unit 26 determines that the object O is a stationary object.

Here, a specific example of the setting method of the threshold value Th3 will be described. By the time the vehicle 1 is shipped at the latest, the threshold Th3 is set as follows.

For example, first, when the object O is one pole, the measured value of the first feature amount FV1 and the measured value of the fluctuation amount ΔFV2 are collected. Further, when the object O is two poles, the measured value of the first feature amount FV1 and the measured value of the fluctuation amount ΔFV2 are collected. Further, when the object O is a pedestrian, the measured value of the first feature amount FV1 and the measured value of the fluctuation amount ΔFV2 are collected.

These values are plotted in the coordinate system CS2 having the first axis corresponding to the first feature amount FV1 and having the second axis corresponding to the fluctuation amount ΔFV2. By clustering the plotted point cloud, the area A4_1 corresponding to one pole, the area A4_2 corresponding to two poles, and the area A4_3 corresponding to a pedestrian are set (see FIG. 19).

Next, a curve corresponding to the threshold value Th3 (hereinafter referred to as "discrimination curve") is set based on the regions A4_1 and A4_2 corresponding to the stationary object and the region A4_3 corresponding to the pedestrian (see FIG. 19). A machine learning technique may be used for setting the regions A4_1, A4_2, and A4_3, and setting the discrimination curve corresponding to the threshold value Th3.

As a result, the threshold value Th3 is set by the time the vehicle 1 is shipped at the latest. In the state where the threshold value Th3 is set, the third pedestrian discrimination unit 26 determines whether the object O is a pedestrian or a stationary object by using the set threshold value Th3 as described above.

Transmission control unit 11, vehicle information acquisition unit 12, position calculation unit 13, warning necessity determination unit 14, warning signal output unit 15, reception control unit 21, echo detection unit 22, first pedestrian discrimination unit 23, fuselage discrimination unit The main part of the control device 4b is composed of the 24 and the third pedestrian discrimination unit 26. Further, the reception control unit 21, the echo detection unit 22, the first pedestrian discrimination unit 23, the body discrimination unit 24, and the third pedestrian discrimination unit 26 constitute the main part of the obstacle detection device 100b.

In this way, the main part of the obstacle detection system 200b is configured.

Since the hardware configuration of the main part of the control device 4b is the same as that described with reference to FIG. 12 in the first embodiment, the illustration and description will be omitted. That is, the transmission control unit 11, the vehicle information acquisition unit 12, the position calculation unit 13, the warning necessity determination unit 14, the warning signal output unit 15, the reception control unit 21, the echo detection unit 22, the first pedestrian determination unit 23, and the fuselage. The functions of the discriminating unit 24 and the third pedestrian discriminating unit 26 may be realized by, for example, the processor 31 and the memory 32, or may be realized by the dedicated processing circuit 33.

In the obstacle detection system 200b, the discrimination result by the third pedestrian discrimination unit 26 is used with priority over the discrimination result by the first pedestrian discrimination unit 23. For example, when the discrimination result by the first pedestrian discrimination unit 23 indicates a pedestrian and the discrimination result by the third pedestrian discrimination unit 26 indicates a stationary object, the body discrimination unit 24 and the position calculation unit 13 In the warning necessity determination unit 14 and the like, the object O is regarded as a stationary object. Alternatively, for example, when the discrimination result by the first pedestrian discrimination unit 23 indicates a stationary object and the discrimination result by the third pedestrian discrimination unit 26 indicates a pedestrian, the body discrimination unit 24, the position calculation In the unit 13 and the warning necessity determination unit 14, the object O is regarded as a pedestrian.

That is, it can be said that the third pedestrian discrimination unit 26 confirms the discrimination result by the first pedestrian discrimination unit 23. Hereinafter, in the third embodiment, the processes executed by the third pedestrian discrimination unit 26 are collectively referred to as "discrimination result confirmation process".

Next, with reference to the flowchart of FIG. 20, regarding the operation of the control device 4b, the transmission control unit 11, the reception control unit 21, the echo detection unit 22, the first pedestrian discrimination unit 23, the third pedestrian discrimination unit 26, The operations of the body determination unit 24 and the position calculation unit 13 will be mainly described. In FIG. 20, the same steps as those shown in FIG. 13 are designated by the same reference numerals, and the description thereof will be omitted. The control device 4b repeatedly executes the process shown in FIG. 20 when the vehicle 1 is moving backward.

First, the processes of steps ST1 to ST7 are executed. Since the processing contents of steps ST1 to ST7 are the same as those described with reference to the flowchart of FIG. 13 in the first embodiment, the description thereof will be omitted again.

Following step ST7, the third pedestrian discrimination unit 26 determines whether or not the execution condition of the discrimination result confirmation process is satisfied (step ST31).

That is, the third pedestrian discrimination unit 26 has the number of detected first echo group EG1 (that is, the number of detections) and the detected second echo group EG2 for the object O detected by the object detection process this time. Calculate the number (ie, the number of detections). When the number of detected echo group EGs is equal to or greater than a predetermined number (for example, M), the third pedestrian discrimination unit 26 determines that the execution condition of the discrimination result confirmation process is satisfied (step ST31 “YES”). .. On the other hand, when the number of detected echo group EGs is less than a predetermined number (for example, M), the third pedestrian discrimination unit 26 determines that the execution condition of the discrimination result confirmation process is not satisfied (step ST31 "NO". ").

When it is determined that the execution condition of the discrimination result confirmation process is satisfied (step ST31 “YES”), the third pedestrian discrimination unit 26 then executes the discrimination result confirmation process (step ST32). Since the details of the determination result confirmation process have already been described with reference to FIG. 19, the description will be omitted again.

Next, the processes of steps ST8 to ST10 are executed. Since the processing contents of steps ST8 to ST10 are the same as those described with reference to the flowchart of FIG. 13 in the first embodiment, the description thereof will be omitted again.

However, when the discrimination result by the first pedestrian discrimination unit 23 indicates a pedestrian and the discrimination result by the third pedestrian discrimination unit 26 indicates a stationary object, step ST8 “NO” is set. On the other hand, in this case, when the discrimination result by the third pedestrian discrimination unit 26 indicates a pedestrian, step ST8 “YES” is set.

Further, when the discrimination result by the first pedestrian discrimination unit 23 indicates a stationary object and the discrimination result by the third pedestrian discrimination unit 26 indicates a pedestrian, step ST8 “YES” is set. On the other hand, in this case, when the discrimination result by the third pedestrian discrimination unit 26 indicates a stationary object, step ST8 “NO” is set.

Next, a modified example of the obstacle detection system 200b will be described.

The first feature amount FV1 is not limited to the above specific example. The third pedestrian discrimination unit 26 may calculate the first feature amount FV1 as follows. Further, the second feature amount FV2 is not limited to the above specific example. The third pedestrian discrimination unit 26 may calculate the fluctuation amount ΔFV2 as follows.

<First modification of the first feature amount FV1 or the second feature amount FV2>
The third pedestrian discrimination unit 26 calculates the total value of the first echo number NE1 in each of the M first echo group EG1 and the second echo number NE2 in the corresponding second echo group EG2. The third pedestrian discrimination unit 26 uses the average value of the calculated total values for the first feature amount FV1. Alternatively, the third pedestrian discrimination unit 26 uses the calculated total value for the second feature amount FV2 to calculate the fluctuation amount ΔFV2.

<Second modification of the first feature amount FV1 or the second feature amount FV2>
The third pedestrian discrimination unit 26 calculates the total value of the total value of the echo width EW in each of the M first echo group EG1 and the total value of the echo width EW in the corresponding second echo group EG2. The third pedestrian discrimination unit 26 uses the average value of the calculated total values for the first feature amount FV1. Alternatively, the third pedestrian discrimination unit 26 uses the calculated total value for the second feature amount FV2 to calculate the fluctuation amount ΔFV2.

<Third modification example of the first feature amount FV1 or the second feature amount FV2>
The third pedestrian discrimination unit 26 calculates the total value of the first area S1 in each of the M first echo group EG1 and the second area S2 in the corresponding second echo group EG2. The third pedestrian discrimination unit 26 uses the average value of the calculated total values for the first feature amount FV1. Alternatively, the third pedestrian discrimination unit 26 uses the calculated total value for the second feature amount FV2 to calculate the fluctuation amount ΔFV2.

<Fourth modification of the first feature amount FV1 or the second feature amount FV2>
The third pedestrian discrimination unit 26 uses M determination result signals RS'corresponding to M first received signals RS1 and M determination result signals RS' corresponding to M second received signals RS2. Then, the first feature amount FV1 or the fluctuation amount ΔFV2 is calculated.

Specifically, for example, the third pedestrian discrimination unit 26 relates to the number of object detection units in the determination result signal RS'corresponding to each of the M first reception signals RS1 and the corresponding second reception signal RS2. The total value with the number of object detection units in the determination result signal RS'is calculated. The third pedestrian discrimination unit 26 uses the average value of the calculated total values for the first feature amount FV1. Alternatively, the third pedestrian discrimination unit 26 uses the calculated total value for the second feature amount FV2 to calculate the fluctuation amount ΔFV2.

Alternatively, for example, the third pedestrian discrimination unit 26 has the total value of the waveform widths in the judgment result signals RS'corresponding to each of the M first reception signals RS1 and the judgment result signal related to the corresponding second reception signal RS2. Calculate the total value with the total value of the waveform width in RS'. The third pedestrian discrimination unit 26 uses the average value of the calculated total values for the first feature amount FV1. Alternatively, the third pedestrian discrimination unit 26 uses the calculated total value for the second feature amount FV2 to calculate the fluctuation amount ΔFV2.

Alternatively, for example, the third pedestrian discrimination unit 26 has the total value of the waveform areas in the judgment result signals RS'corresponding to each of the M first reception signals RS1 and the judgment result signal related to the corresponding second reception signal RS2. Calculate the total value with the total value of the waveform area in RS'. The third pedestrian discrimination unit 26 uses the average value of the calculated total values for the first feature amount FV1. Alternatively, the third pedestrian discrimination unit 26 uses the calculated total value for the second feature amount FV2 to calculate the fluctuation amount ΔFV2.

Further, the obstacle detection device 100b may not have the first pedestrian determination unit 23. In this case, the discrimination result by the third pedestrian discrimination unit 26 may be used instead of the discrimination result by the first pedestrian discrimination unit 23. However, from the viewpoint of early determination of whether the object O is a pedestrian or a stationary object, it is more preferable that the first pedestrian determination unit 23 is provided.

In addition, the obstacle detection system 200b can employ various modifications similar to those described in the first embodiment.

As described above, the obstacle detection device 100b uses the first feature amount FV1 based on the number of echoes NE in the echo group EG and the fluctuation amount ΔFV2 of the second feature amount FV2 based on the echo width EW in the echo group EG. A third pedestrian discrimination unit 26 is provided which determines whether or not the object O is a pedestrian and outputs the result of the determination. Thereby, for example, the discrimination result by the first pedestrian discrimination unit 23 can be confirmed. As a result, the accuracy of determining whether or not the object O is a pedestrian can be further improved.

In the present invention, within the scope of the invention, it is possible to freely combine each embodiment, modify any component of each embodiment, or omit any component in each embodiment. ..

The obstacle detection device of the present invention can be used for, for example, AEB (Autonomous Emergency Braking).

1 vehicle, 2 sonar, 3 rear sonar, 4, 4a, 4b control device, 5 sensors, 6 output device, 11 transmission control unit, 12 vehicle information acquisition unit, 13 position calculation unit, 14 warning necessity judgment unit, 15 warning Signal output unit, 21 reception control unit, 22 echo detection unit, 23 first pedestrian discrimination unit, 24 body discrimination unit, 25 second pedestrian discrimination unit, 26 third pedestrian discrimination unit, 31 processor, 32 memory, 33 Processing circuit, 100, 100a, 100b obstacle detection device, 200, 200a, 200b obstacle detection system.

Claims (10)

1. The first received signal corresponding to the first reflected wave reflected by an object existing around the vehicle and the second received signal corresponding to the second reflected wave reflected by the object in a direction different from the first reflected wave. A reception control unit that acquires a reception signal including
   An echo detection unit that detects an echo group including a first echo group in the first received signal and a second echo group in the second received signal.
   Based on the detection result by the echo detection unit, when a plurality of echoes exist in a window having a width corresponding to a pedestrian, the object is determined to be the pedestrian and the result of the determination is output. The first pedestrian discrimination unit and
   Obstacle detection device equipped with.
2. The first aspect of claim 1, wherein the body discriminating unit for discriminating the echo corresponding to the pedestrian's body among the plurality of echoes based on the number of echoes in the echo group or the echo width in the echo group is provided. Obstacle detection device.
3. When the number of echoes is 3 or more, the body discriminating unit corresponds to the body in the echoes arranged in the central portion excluding the echoes arranged at both ends in the window among the plurality of echoes. The obstacle detection device according to claim 2, wherein it is determined to be an echo.
4. The obstacle detecting device according to claim 2, wherein the body discriminating unit determines that the echo having the maximum echo width among the plurality of echoes is the echo corresponding to the body.
5. The body discriminating unit is
   For each of the plurality of echoes, the difference value between the actual peak value and the estimated peak value based on the echo width is calculated.
   The obstacle detection device according to claim 2, wherein the echo having the maximum difference value among the plurality of echoes is determined to be the echo corresponding to the body.
6. The obstacle according to claim 1, wherein the first reflected wave and the reflected wave including the second reflected wave are received by a plurality of sonars provided at different positions in the vehicle. Detection device.
7. The obstacle detection device according to claim 6, wherein the rear sonar is composed of the plurality of sonars.
8. A second pedestrian discriminating unit that determines whether or not the object is a pedestrian based on the degree of similarity between the first echo group and the second echo group and outputs the result of the determination is provided. The obstacle detection device according to claim 1, wherein the obstacle detection device is characterized.
9. Using the first feature amount based on the number of echoes in the echo group and the variation amount of the second feature amount based on the echo width in the echo group, it is determined whether or not the object is the pedestrian. The obstacle detection device according to claim 1, further comprising a third pedestrian discrimination unit that outputs the result of the discrimination.
10. The obstacle detection device according to claim 1, wherein the road surface is included in the irradiation range of the exploration wave by the plurality of sonars.

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