WO2025163959A1 - Object detection device - Google Patents

Abstract

This object detection device is provided with: a transmitting and receiving unit for transmitting transmission waves and for receiving reflected waves produced by reflection of the transmission waves at an object; a coordinate computation unit for calculating coordinates indicating the location of an object present in the periphery of a mobile object on the basis of echo information indicating time-series changes in the intensity of the reflected waves; and a determination unit for determining that a low-detection target, which is an object that is subject to detection and has a height lower than a threshold value, is present if the coordinates of an object present in a region in a direction of advance of the mobile object are within a predetermined region that is established in advance as a region in which horizontal attenuation of the transmission waves is sufficiently little, the same object has been detected continuously for a predetermined length of time, and the intensity of the reflected waves has been attenuating along with movement of the mobile object in the direction of advance.

Description

Object detection device

An embodiment of the present invention relates to an object detection device.

Object detection devices are used to detect objects around a vehicle based on information acquired by transmitting and receiving waves such as ultrasound. A technology has been disclosed for such object detection devices that determines whether a detected object is a low object, such as a curb, that will not collide with the vehicle, based on the difference between theoretical reflection intensity and actual reflection intensity (Patent Document 1).

JP 2016-80639 A

However, in configurations that use theoretical reflection intensity, such as in conventional technology, the theoretical reflection intensity varies depending on the object being detected, making it difficult to detect low-reflection objects with high accuracy.

One of the problems that embodiments of the present invention aim to solve is to provide an object detection device that can detect low objects with high accuracy.

An object detection device according to one embodiment of the present invention is an object detection device that detects objects present in the vicinity of a moving body, and includes: a transmitter/receiver unit that transmits transmitted waves and receives reflected waves generated when the transmitted waves are reflected by objects; a coordinate calculation unit that calculates coordinates indicating the position of objects present in the vicinity of the moving body based on echo information that indicates time-series changes in the intensity of the reflected waves; and a determination unit that determines that a low-detection target, which is an object that is the target of detection and whose height is lower than a threshold, is present if the coordinates of an object present in an area in the direction of travel of the moving body are within a predetermined area that is determined as an area where the horizontal attenuation of the transmitted waves is sufficiently small, the same object has been detected continuously for a predetermined period of time, and the intensity of the reflected waves is attenuating as the moving body moves in the direction of travel.

With the above configuration, if the coordinates of an object present in the area in the direction of travel of the moving body are within a predetermined area where the horizontal attenuation of the transmitted wave is sufficiently small, and the same object has been detected continuously for a predetermined period of time, and the strength of the reflected wave is attenuating as the moving body moves, it is determined that a low-detection object that is the target of detection and whose height is lower than the threshold value is present. This makes it possible to detect low-detection objects such as curbs that have weak reflected wave strength with high accuracy.

Furthermore, in the above configuration, the determination unit may determine whether the same object has been detected based on the difference between multiple coordinates calculated at predetermined time intervals.

The above configuration makes it possible to determine with high accuracy whether the same object is being detected.

Another embodiment of the present invention is an object detection device that detects objects present in the vicinity of a moving body, and includes a transceiver unit that transmits transmission waves and receives reflected waves generated when the transmission waves are reflected by the object; a coordinate calculation unit that calculates coordinates indicating the position of an object present in the vicinity of the moving body based on echo information that indicates time-series changes in the intensity of the reflected waves; a distance calculation unit that calculates the distance from the moving body to the object based on the echo information; a height calculation unit that calculates the height of the object based on multiple distances calculated by the distance calculation unit; and a determination unit that determines that a low-detection target object, which is an object to be detected and whose height is lower than the threshold, is present if the coordinates of the object present in the area in the direction of travel of the moving body are within a predetermined area that is a region where the horizontal attenuation of the transmission waves is sufficiently small, the same object has been detected continuously for a predetermined time, the intensity of the reflected waves is attenuating as the moving body moves in the direction of travel, and the amount of change in height calculated by the height calculation unit remains smaller than the threshold for a predetermined time.

With the above configuration, if the coordinates of an object present in the area in the direction of travel of the moving body are within a predetermined area where the horizontal attenuation of the transmitted wave is sufficiently small, and the same object has been detected continuously for a predetermined period of time, and the strength of the reflected wave is attenuating as the moving body moves, and the amount of change in the object's height remains smaller than the threshold for a predetermined period of time, it is determined that a low-detection object that is the target of detection and whose height is lower than the threshold is present. This makes it possible to more accurately detect low-detection objects such as curbs that have weak reflected wave strength.

Furthermore, in the above configuration, the determination unit may determine that the low detection object is present when the intensity of the reflected wave attenuates by a predetermined amount or more as the moving object moves.

The above configuration makes it possible to detect low-profile objects with higher accuracy.

FIG. 1 is a diagram showing an example of the configuration of a vehicle according to the first embodiment. FIG. 2 is a diagram illustrating an example of the configuration of the vehicle control system according to the first embodiment. FIG. 3 is a diagram showing an example of a distance calculation method using the TOF method according to the first embodiment. FIG. 4 is a diagram illustrating an example of the functional configuration of the object detection device according to the first embodiment. FIG. 5 is a diagram illustrating an example of the relationship between a change in the position of a low detection object and a change in the intensity of a reflected wave according to the first embodiment. FIG. 6 is a flowchart showing an example of processing in the object detection device according to the first embodiment. FIG. 7 is a diagram illustrating an example of the functional configuration of the object detection device according to the second embodiment. FIG. 8 is a flowchart showing an example of processing in the object detection device according to the second embodiment.

Embodiments of the present disclosure will be described below with reference to the drawings. The configurations of the embodiments described below and the actions and effects achieved by such configurations are merely examples, and the present invention is not limited to the contents of the following description.

(First embodiment)
1 is a diagram showing an example of the configuration of a vehicle 1 according to the first embodiment. The vehicle 1 is an example of a moving body on which an object detection device according to the present embodiment is mounted. The object detection device according to the present embodiment is a device that detects objects present around the vehicle 1 based on information such as time of flight (TOF) and Doppler shift acquired by transmitting and receiving ultrasonic waves.

The object detection device according to this embodiment includes multiple transceivers 21A-21L. Hereinafter, when there is no need to distinguish between the multiple transceivers 21A-21L, they may be referred to as transceiver 21. Each transceiver 21 is installed on the vehicle body 2, which serves as the exterior of the vehicle 1, and transmits ultrasonic waves toward the outside of the vehicle body 2, receiving ultrasonic waves generated when the ultrasonic waves are reflected by an object outside the vehicle body 2. Hereinafter, ultrasonic waves transmitted from the transceiver 21 may be referred to as transmitted waves, and ultrasonic waves generated when the transmitted waves are reflected by an object may be referred to as reflected waves.

In the example shown in Figure 1, four transceivers 21A-21D are located at the front end of the vehicle body 2, four transceivers 21E-21H are located at the rear end, two transceivers 21I and 21J are located on the right side, and two transceivers 21K and 21L are located on the left side. Note that the number and installation locations of the transceivers 21 are not limited to this example.

FIG. 2 is a diagram showing an example of the configuration of a vehicle control system 10 according to the first embodiment. The vehicle control system 10 performs processing to control the vehicle 1 based on information output from an object detection device 11. The vehicle control system 10 according to this embodiment includes an object detection device 11 and an ECU 12.

The object detection device 11 includes multiple transmitter/receivers 21 and a control unit 22. Each transmitter/receiver 21 includes a vibrator 31 constructed using a piezoelectric element or the like, an amplifier, etc., and transmits and receives ultrasonic waves through the vibration of the vibrator 31. Specifically, each transmitter/receiver 21 transmits ultrasonic waves generated in response to the vibration of the vibrator 31 as a transmission wave, and detects the vibration of the vibrator 31 caused by the reflected wave when the transmission wave is reflected by an object such as the detection target O or the road surface G. The vibration of the vibrator 31 is converted into an electrical signal, and based on this electrical signal, it is possible to obtain the TOF corresponding to the distance from the transmitter/receiver 21 to the detection target O, the Doppler shift corresponding to the relative speed between the vehicle 1 and the detection target O, etc.

Detection targets O are objects that exist around the vehicle 1 and should be subject to detection. Detection targets O include high detection targets, which are objects with a height equal to or greater than a threshold, and low detection targets, which are objects with a height lower than the threshold. The threshold may be, for example, the height from the road surface G to the bottom of the vehicle body 2 (such as the bottom end of the bumper). High detection targets may be, for example, other vehicles, road accessories, walls, people, etc. Low detection targets may be, for example, curbs, bollards, small steps, etc.

In the example shown in Figure 2, a configuration is illustrated in which both the transmission of the transmitted wave and the reception of the reflected wave are performed using a single oscillator 31, but the configuration of the transmitter/receiver unit 21 is not limited to this. For example, the transmitting side and receiving side may be separated, such as a configuration in which an oscillator for transmitting the transmitted wave and an oscillator for receiving the reflected wave are separately provided.

The control unit 22 includes an input/output device 41, a storage device 42, and a processor 43. The input/output device 41 is an interface device that enables the transmission and reception of information between the control unit 22 and external devices (such as the transceiver unit 21 and ECU 12). The storage device 42 includes main storage devices such as ROM (Read Only Memory) and RAM (Random Access Memory), and auxiliary storage devices such as HDDs (Hard Disk Drives) and SSDs (Solid State Drives). The processor 43 is an integrated circuit that performs various processes to realize the functions of the control unit 22, and may be configured using, for example, a CPU (Central Processing Unit), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), etc. that operate according to a program. The processor 43 performs various arithmetic and control processes by reading and executing programs stored in the storage device 42.

The ECU 12 is a unit that executes various processes for controlling the vehicle 1 based on information obtained from the object detection device 11 and the like. The ECU 12 has an input/output device 51, a storage device 52, and a processor 53. The input/output device 51 is an interface device that enables the transmission and reception of information between the ECU 12 and external mechanisms (such as the object detection device 11, drive mechanism, braking mechanism, steering mechanism, transmission mechanism, in-vehicle display, speakers, and various sensors). The storage device 52 includes main storage devices such as ROM and RAM, and auxiliary storage devices such as HDD and SSD. The processor 53 is an integrated circuit that executes various processes for realizing the functions of the ECU 12, and may be configured using, for example, a CPU, ASIC, FPGA, etc. The processor 53 reads programs stored in the storage device 52 and executes various arithmetic and control processes.

FIG. 3 is a diagram showing an example of a method for calculating distance using the TOF method according to the first embodiment. FIG. 3 illustrates an envelope L11 (an example of echo information) that indicates the change over time in the intensity (signal level) of the ultrasound transmitted and received by the transmitter/receiver 21. In the graph shown in FIG. 3, the horizontal axis corresponds to time (TOF), and the vertical axis corresponds to the intensity of the ultrasound transmitted and received by the transmitter/receiver 21 (the magnitude of vibration of the transducer 31).

Envelope L11 shows the change over time in intensity, which indicates the magnitude of vibration of vibrator 31. From envelope L11 shown in Figure 3, it can be seen that vibrator 31 is driven to vibrate for time Ta from time t0, completing the transmission of the transmission wave at time t1, and then for time Tb until time t2, the vibration of vibrator 31 due to inertia continues, attenuating. Therefore, in the graph shown in Figure 3, time Tb corresponds to the so-called reverberation time.

Envelope L11 reaches a peak at time t4, a time Tp after time t0 when transmission of the transmission wave begins, where the magnitude of the vibration of vibrator 31 exceeds detection threshold Ith. This detection threshold Ith is a value set to distinguish whether the vibration of vibrator 31 is caused by receiving a reflected wave from the detection object O, or by receiving a reflected wave from an object other than the detection object O (such as the road surface G). Note that while detection threshold Ith is shown here as a constant value, detection threshold Ith may also be a variable value that changes depending on the situation. Vibrations with a peak equal to or greater than detection threshold Ith can be considered to be caused by receiving a reflected wave from the detection object O.

In this example, envelope L11 shows that the vibration of vibrator 31 attenuates after timing t4. Therefore, timing t4 corresponds to the timing when reception of the reflected wave from the detection object O is completed; in other words, the timing when the last transmitted wave transmitted at timing t1 returns as a reflected wave.

Furthermore, in envelope L11, timing t3, which is the start point of the peak at timing t4, corresponds to the timing when reception of the reflected wave from the detection object O begins; in other words, the timing when the transmitted wave first transmitted at timing t0 returns as a reflected wave. Therefore, the time ΔT between timing t3 and timing t4 is equal to the time Ta, which is the transmission time of the transmitted wave.

From the above, in order to use TOF to find the distance from the transmitter/receiver unit 21, which is the source of the ultrasonic waves, to the detection target O, it is necessary to find the time Tf between the time t0 when the transmitted wave begins to be transmitted and the time t3 when the reflected wave begins to be received. This time Tf can be found by subtracting the time ΔT, which is equal to the time Ta, which is the transmission time of the transmitted wave, from the time Tp, which is the difference between the time t0 and the time t4 when the intensity of the reflected wave exceeds the detection threshold Ith and reaches its peak.

The time t0 when the transmission wave begins to be transmitted can be easily identified as the time when the object detection device 200 begins operating, and the time Ta as the transmission time of the transmission wave is predetermined by settings, etc. Therefore, by identifying the time t4 when the intensity of the reflected wave reaches a peak above the detection threshold Ith, the distance from the vehicle 1 (the transmitter/receiver unit 21, which is the source of the ultrasonic waves) to the detection object O can be calculated. Note that the above calculation method is an example, and the distance from the vehicle 1 to the detection object O can be calculated using any known or new method as appropriate.

Here, the strength of the reflected waves from low-detection objects such as curbs tends to be weak due to factors such as the directivity of the transmitted waves. Therefore, it may be difficult to detect low-detection objects with high accuracy using only the method described above. Therefore, the object detection device 11 according to this embodiment is equipped with a function that enables high-accuracy detection of low-detection objects.

FIG. 4 is a diagram showing an example of the functional configuration of the object detection device 11 according to the first embodiment. The control unit 22 of the object detection device 11 according to this embodiment includes an echo information generation unit 101, a coordinate calculation unit 102, a determination unit 103, and an output unit 104. These functional units can be realized, for example, by cooperation between the hardware and software (programs, etc.) of the object detection device 11 as shown in FIG. 2. Furthermore, at least some of these functional units may be realized by dedicated hardware (circuits).

The echo information generation unit 101 generates echo information that indicates the time-series changes in the intensity of the reflected wave based on the information (signal) acquired from the transmission/reception unit 21.

The coordinate calculation unit 102 calculates coordinates indicating the position of an object present in the vicinity of the vehicle 1 based on the echo information generated by the echo information generation unit 101. These coordinates are information that can identify the relative positional relationship between the transmitter/receiver unit 21 and the object, and can be, for example, information indicating a position on a plane coordinate system in which the width direction of the vehicle 1 is the X axis and the longitudinal direction of the vehicle 1 is the Y axis.

The determination unit 103 determines whether an object present in the vicinity of the vehicle 1 is a low-detection object based on information such as coordinates calculated by the coordinate calculation unit 102. Specifically, if the coordinates of an object present in the area in the direction of travel of the vehicle 1 are within a predetermined area where the horizontal attenuation of the transmitted wave is sufficiently small, if the same object has been detected continuously for a predetermined period of time, and if the intensity of the reflected wave is attenuating as the moving object moves in the direction of travel, the determination unit 103 determines that a low-detection object, which is an object that is subject to detection and whose height is lower than a threshold, is present in the area in the direction of travel of the moving object.

The output unit 104 outputs the determination result by the determination unit 103, i.e., the object detection result including information indicating whether or not there is a low-detection object in the vicinity of the vehicle 1 (such as the area in the direction of travel), to a predetermined mechanism (such as the ECU 12).

5 is a diagram showing an example of the relationship between the change in position of the low detection object O _low and the change in intensity of the reflected wave according to the first embodiment. The upper part of FIG. 5 shows a top view illustrating the relative positional relationship between the vehicle 1 (transmitter/receiver 21) and the low detection object O _low . Here, the low detection object O _low is not moving, and the vehicle 1 is moving in the direction of the arrow, i.e., in the direction approaching the low detection object O _low .

Position P0 is the position of the low detection object O _low detected at time t0. Position P1 is the position of the low detection object O _low detected at time t1, a predetermined time after time t0. Position P2 is the position of the low detection object O _low detected at time t2, a predetermined time after time t1. Position P3 is the position of the low detection object O _low detected at time t4, a predetermined time after time t2. The predetermined time here may be, for example, the time equivalent to one detection cycle. One detection cycle is, for example, the time from when a transmission wave is transmitted once to when waiting for reception of a reflected wave is completed.

The moving distance Δd1 is the distance from position P0 to position P1, the moving distance Δd2 is the distance from position P1 to position P2, and the moving distance Δd3 is the distance from position P2 to position P3. Based on these moving distances Δd1 to Δd3, it can be determined whether the same object (low detection target O _low ) is continuously detected. That is, based on the difference between multiple coordinates calculated at predetermined time intervals, it can be determined whether the same object is continuously detected. For example, if the same object is continuously detected, the moving distances Δd1 to Δd3 calculated during that time will be relatively small values. However, if another object is detected along the way, it is likely that the moving distances Δd1 to Δd3 will suddenly increase. Therefore, it can be determined that the same object is continuously detected as long as the moving distances Δd1 to Δd3 remain smaller than the threshold value.

5 illustrates a predetermined area A as an area where horizontal attenuation of the transmission wave transmitted from the transmitter/receiver 21 is sufficiently small. Area A can be determined based on the results of a verification experiment, simulation, or the like conducted in advance. Here, an example is shown in which the coordinates of each position P0 to P3 of the low detection object O _low are located within area A.

The lower part of Figure 5 illustrates the intensities I0 to I3 of the reflected waves corresponding to the positions P0 to P3 of the low detection object O _low . As shown in the figure, the intensity of the reflected waves from the low detection object O _low decreases as the vehicle 1 moves closer to the low detection object O _low , i.e., as the distance between the transmitter/receiver 21 and the low detection object O _low decreases. This is due to the directivity of the transmission waves sent from the transmitter/receiver 21, etc. Therefore, when such a change in the intensity of the reflected waves is detected, it can be inferred that there is a high possibility that the low detection object O _low is present in the area in the direction of travel of the vehicle 1.

FIG. 6 is a flowchart showing an example of processing in the object detection device 11 according to the first embodiment. When the transmitter/receiver 21 starts transmitting and receiving ultrasonic waves (S101), the echo information generator 101 generates echo information indicating time-series changes in the reflected waves based on information acquired from the transmitter/receiver 21 (S102). The coordinate calculation unit 102 determines whether an object is present around the vehicle 1 based on the echo information (S103). If no object is present (S103: No), the routine ends, and if an object is present (S103: Yes), the coordinates of the object are calculated (S104).

Then, the determination unit 103 determines whether the calculated coordinates of the object are within a predetermined area (area A) (S105), and if the coordinates are not within the predetermined area (S105: No), ends this routine. If the coordinates are within the predetermined area (S105: Yes), the determination unit 103 determines whether the same object has been detected continuously for a predetermined time (S106). Whether the same object has been detected continuously can be determined based on, for example, the difference between the coordinates of multiple objects calculated every predetermined time, as described above.

If the same object has not been detected for a predetermined period of time (S106: No), the routine is terminated. If the same object has been detected for a predetermined period of time (S106: Yes), the determination unit 103 determines whether the intensity of the reflected wave has attenuated by a predetermined amount or more as the vehicle 1 moves (S107). If the intensity of the reflected wave has not attenuated (S107: No), the routine is terminated. If the intensity of the reflected wave has attenuated (S107: Yes), the determination unit 103 determines that a low detection object O _low is present in the area in the traveling direction of the vehicle 1 (S108).

As described above, according to this embodiment, it is determined that there is a low detection object O low that is the target of detection and whose height is lower than the threshold value if the coordinates of an object present in the area in the traveling direction of the vehicle 1 are within the predetermined area A, which is an area where the horizontal attenuation of the transmitted wave is sufficiently small, the same object is continuously detected for a predetermined time, and the intensity of the reflected wave is attenuating as the vehicle ₁ moves. This makes it possible to detect low detection objects O _low , such as curbs, that have weak reflected wave intensity, with high accuracy.

Other embodiments will be described below with reference to the drawings. Components that are the same as or similar to those in the first embodiment will be given the same reference numerals, and their description will be omitted where appropriate.

Second Embodiment
The object detection device 11 according to the second embodiment differs from the first embodiment in that the condition for determining whether or not a low detection object O _low is present includes whether or not a state in which the fluctuation in the height of an object present around the vehicle 1 is small continues for a predetermined time (predetermined section).

FIG. 7 is a diagram showing an example of the functional configuration of an object detection device 11 according to the second embodiment. The control unit 22 of the object detection device 11 of this embodiment includes an echo information generation unit 101, a coordinate calculation unit 102, a determination unit 103, an output unit 104, a distance calculation unit 111, and a height calculation unit 112.

The distance calculation unit 111 calculates the distance between the vehicle 1 (transmitter/receiver 21) and an object present in the vicinity of the vehicle 1 based on the echo information generated by the echo information generation unit 101 and the coordinates of the object calculated by the coordinate calculation unit 102. The distance may be calculated using any known or new method as appropriate, and may be calculated based on information such as TOF, for example.

The height calculation unit 112 calculates the height of objects present in the vicinity of the vehicle 1 based on the distance calculated by the distance calculation unit 111. The height may be calculated using any known or new method as appropriate, but may be calculated, for example, based on the difference between two distances calculated for objects present at the same or approximately the same coordinates.

The determination unit 103 according to this embodiment determines that a low detection object O low is present in the area in the direction of travel of the moving body when the coordinates of an object present in the area in the direction of travel of the vehicle 1 are within a predetermined area (area A) that has been determined in advance as an area in which the horizontal attenuation of the transmitted wave is sufficiently small, the same object has been detected continuously for a predetermined period of time, the intensity of the reflected wave is _attenuating as the vehicle 1 moves in the direction of travel, and the amount of change in height calculated by the height calculation unit 112 is smaller than a threshold value for a predetermined period of time.

FIG. 8 is a flowchart showing an example of processing in the object detection device 11 according to the second embodiment. When the transmitter/receiver 21 starts transmitting and receiving ultrasonic waves (S201), the echo information generator 101 generates echo information indicating time-series changes in the reflected waves based on information acquired from the transmitter/receiver 21 (S202). The coordinate calculation unit 102 determines whether an object is present around the vehicle 1 based on the echo information (S203). If no object is present (S203: No), the routine ends; if an object is present (S203: Yes), the coordinates of the object are calculated (S204).

Then, the distance calculation unit 111 calculates the distance from the vehicle 1 (transmitter/receiver 21) to the object based on the object's coordinates and echo information calculated as described above, and the height calculation unit 112 calculates the height of the object based on the distance to the object (S205). At this time, the distance calculation unit 111 calculates two distances for objects that exist on the same or approximately the same coordinates, and the height calculation unit 112 calculates the height of the object based on the two distances.

Then, the determination unit 103 determines whether the calculated coordinates of the object are within a predetermined area (area A) (S206), and if the coordinates are not within the predetermined area (S206: No), ends this routine. If the coordinates are within the predetermined area (S206: Yes), the determination unit 103 determines whether the same object has been detected for a predetermined period of time (S207).

If the same object has not been detected for a predetermined period of time (S207: No), this routine is terminated. If the same object has been detected for a predetermined period of time (S207: Yes), the determination unit 103 determines whether the intensity of the reflected wave has attenuated by a predetermined amount or more as the vehicle 1 moves (S208). If the intensity of the reflected wave has not attenuated (S208: No), this routine is terminated. If the intensity of the reflected wave has attenuated (S208: Yes), the determination unit 103 determines whether the amount of change in the object's height is less than the threshold value for a predetermined period of time (S209).

If the state in which the amount of change in the object height is smaller than the threshold value has not continued for a predetermined time (S209: No), this routine is terminated, and if the state in which the amount of change in the object height is smaller than the threshold value has continued for a predetermined time (S209: Yes), the determination unit 103 determines that a low detection object O _low is present in the area in the direction of travel of the vehicle 1 (S210).

As described above, according to this embodiment, if the coordinates of an object present in the area in the traveling direction of the vehicle 1 are within the predetermined area A where the horizontal attenuation of the transmitted wave is sufficiently small, the same object has been detected continuously for a predetermined time, the intensity of the reflected wave has been attenuated as the vehicle 1 moves, and the amount of change in the height of the object has remained smaller than the threshold value for a predetermined time, it is determined that a low detection object O _low that is the target of detection and whose height is lower than the threshold value is present. In this way, by making a determination taking into account the change in the height of the object, it is possible to detect the low detection object O _low with higher accuracy.

The program that causes a computer (such as the processor 43) to execute the processing required to realize the functions of the object detection device 11 can be provided by recording it in an installable or executable file format on a computer-readable recording medium such as a CD (Compact Disc)-ROM, a flexible disk (FD), a CD-R (Recordable), or a DVD (Digital Versatile Disk). The program may also be provided or distributed via a network such as the Internet.

In the above embodiment, a configuration was described in which ultrasonic waves were used as waves to detect objects, but the configuration of the object detection device is not limited to this. For example, a configuration using millimeter-wave radar, LiDAR, etc. may also be used.

The above describes embodiments of the present invention, but the above-described embodiments and their variations are merely examples and are not intended to limit the scope of the invention. The novel embodiments and variations described above can be implemented in various forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. The above-described embodiments and variations are included within the scope and spirit of the invention, as well as the invention and its equivalents as set forth in the claims.

[Summary of this embodiment]
This embodiment has at least the following configuration.

The object detection device 11 detects objects present in the vicinity of a moving body and includes a transmitter/receiver unit 21 that transmits transmitted waves and receives reflected waves generated when the transmitted waves are reflected by objects; a coordinate calculation unit 102 that calculates coordinates indicating the position of objects present in the vicinity of the moving body based on echo information that indicates time-series changes in the intensity of the reflected waves; and a determination unit 103 that determines that a low-detection object, which is an object that is the target of detection and whose height is lower than a threshold, is present if the coordinates of an object present in an area in the direction of travel of the moving body are within a predetermined area that is determined as an area where the horizontal attenuation of the transmitted waves is sufficiently small, the same object has been detected continuously for a predetermined period of time, and the intensity of the reflected waves is attenuating as the moving body moves in the direction of travel.

With this configuration, if the coordinates of an object present in the area in the direction of travel of the moving body are within a predetermined area where the horizontal attenuation of the transmitted wave is sufficiently small, and the same object has been detected continuously for a predetermined period of time, and the strength of the reflected wave is attenuating as the moving body moves, it is determined that a low-detection object that is the target of detection and whose height is lower than the threshold value is present. This makes it possible to detect low-detection objects such as curbs that have weak reflected wave strength with high accuracy.

Furthermore, the determination unit 103 may determine whether the same object has been detected based on the difference between multiple coordinates calculated at predetermined intervals.

This configuration makes it possible to determine with high accuracy whether the same object is being detected.

The object detection device 11 detects objects present in the vicinity of a moving body and includes a transmitter/receiver unit 21 that transmits transmitted waves and receives reflected waves generated when the transmitted waves are reflected by the object; a coordinate calculation unit 102 that calculates coordinates indicating the position of an object present in the vicinity of the moving body based on echo information that indicates time-series changes in the intensity of the reflected waves; a distance calculation unit 111 that calculates the distance from the moving body to the object based on the echo information; a height calculation unit 112 that calculates the height of the object based on multiple distances calculated by the distance calculation unit; and a determination unit 103 that determines that a low-detection object, which is an object to be detected and whose height is lower than the threshold, is present if the coordinates of the object present in the area in the direction of travel of the moving body are within a predetermined area that is a region where the horizontal attenuation of the transmitted waves is sufficiently small, the same object has been detected continuously for a predetermined time, the intensity of the reflected waves is attenuating as the moving body moves in the direction of travel, and the amount of change in height calculated by the height calculation unit is smaller than the threshold value for a predetermined time.

With this configuration, if the coordinates of an object present in the area in the direction of travel of the moving body are within a predetermined area where the horizontal attenuation of the transmitted wave is sufficiently small, and the same object has been detected continuously for a predetermined period of time, and the strength of the reflected wave is attenuating as the moving body moves, and the amount of change in the object's height remains smaller than the threshold for a predetermined period of time, it is determined that a low-detection object that is the target of detection and whose height is lower than the threshold is present. This makes it possible to more accurately detect low-detection objects such as curbs that have weak reflected wave strength.

Furthermore, in the above configuration, the determination unit may determine that the low detection object is present when the intensity of the reflected wave attenuates by a predetermined amount or more as the moving object moves.

This configuration makes it possible to detect low-profile objects with greater accuracy.

In addition, the effects of the dependent claims and embodiments of the claims are additional effects separate from the effects of the independent claims.

1...vehicle, 2...vehicle body, 10...vehicle control system, 11...object detection device, 12...ECU, 21, 21A to 21L...transmitter/receiver unit, 22...control unit, 31...vibrator, 41...input/output device, 42...storage device, 43...processor, 101...echo information generation unit, 102...coordinate calculation unit, 103...determination unit, 104...output unit, 111...distance calculation unit, 112...height calculation unit, A...area (predetermined area), G...road surface, O...detection object, O _low ...low detection object

Claims (4)

An object detection device that detects objects present around a moving body,
a transceiver that transmits a transmission wave and receives a reflected wave generated when the transmission wave is reflected by an object;
a coordinate calculation unit that calculates coordinates indicating the position of an object present around the moving object based on echo information indicating a time-series change in the intensity of the reflected wave;
a determination unit that determines that a low detection target object, which is an object to be detected and has a height lower than a threshold value, is present when the coordinates of an object present in an area in the traveling direction of the moving body are within a predetermined area that is determined in advance as an area in which horizontal attenuation of the transmitted wave is sufficiently small, the same object has been detected continuously for a predetermined time, and the intensity of the reflected wave is attenuated as the moving body moves in the traveling direction;
An object detection device comprising: the determination unit determines whether or not the same object is detected based on differences between the plurality of coordinates calculated at predetermined time intervals.
The object detection device according to claim 1 . An object detection device that detects objects present around a moving body,
a transceiver that transmits a transmission wave and receives a reflected wave generated when the transmission wave is reflected by an object;
a coordinate calculation unit that calculates coordinates indicating the position of an object present around the moving object based on echo information indicating a time-series change in the intensity of the reflected wave;
a distance calculation unit that calculates a distance from the moving body to an object based on the echo information;
a height calculation unit that calculates a height of an object based on the plurality of distances calculated by the distance calculation unit;
a determination unit that determines that a low detection target object, which is an object to be detected and whose height is lower than a threshold value, is present when the coordinates of an object present in an area in the traveling direction of the moving body are within a predetermined area that is determined in advance as an area where horizontal attenuation of the transmitted wave is sufficiently small, the same object has been detected continuously for a predetermined time, the intensity of the reflected wave has been attenuated as the moving body moves in the traveling direction, and a state in which the amount of change in height calculated by the height calculation unit is smaller than a threshold value has continued for a predetermined time;
An object detection device comprising: The determination unit determines that the low detection object is present when the intensity of the reflected wave is attenuated by a predetermined amount or more as the moving object moves.
The object detection device according to any one of claims 1 to 3.