JP2019095302A - Object detector - Google Patents

Abstract

To provide an object detector with which it is possible to utilize a received indirect wave in determining the presence of an object, when a transmission/reception unit is able to receive only an indirect wave.SOLUTION: The object detector comprises: a survey wave determination unit for determining whether or not a first transmission/reception unit and a second transmission/reception unit have received a direct wave or an indirect wave on the basis of transmission/reception information relating to the transmission/reception of the survey wave acquired from the first transmission/reception unit and second transmission/reception unit that transmit/receive the survey wave to and from the surroundings in order to detect an object, and outputting a determination result; and an object determination unit for calculating, on the basis of the determination result, a sum total for determination that is the sum of first reliability when it is determined that a trigonometrical survey holds good and second reliability when both of the first transmission/reception unit and a second transmission/reception unit have received the indirect wave, and determining the presence of an object on the basis of the sum total for determination.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an object detection apparatus.

  An object detection apparatus is known which is provided in a vehicle or the like and detects an object such as an obstacle around the vehicle. For example, the object detection apparatus detects an object by transmitting a search wave such as an ultrasonic wave and receiving the search wave reflected by the object. Such an object detection apparatus has a plurality of transmission and reception units that transmit and receive a search wave. The object detection apparatus triangulates the direct wave received by the same transmission / reception unit and the indirect wave received by the other transmission / reception unit by the same transmission / reception unit and the direct wave received by the same transmission / reception unit. The position etc. is detected.

JP, 2016-80641, A

  However, the above-described object detection device has a problem that when the transmitting and receiving unit can receive only the indirect wave, the received indirect wave can not be used to detect an object.

  The present invention has been made in view of the above, and it is an object of the present invention to provide an object detection apparatus that can use received indirect waves to determine the presence of an object even when the transmitting and receiving unit can receive only indirect waves. I assume.

  In order to solve the problems described above and to achieve the object, an object detection apparatus according to the present invention is a search wave obtained from a first transmission / reception unit and a second transmission / reception unit that transmits and receives a search wave around to detect an object. A search wave determination unit that determines whether the first transmission / reception unit and the second transmission / reception unit have received a direct wave or an indirect wave based on transmission / reception information related to transmission / reception of Based on the sum of the first reliability when it is determined that triangulation is established, and the second reliability when both the first transmission / reception unit and the second transmission / reception unit receive the indirect wave. And an object determination unit that calculates the total for determination and determines the presence of an object based on the total for determination.

  As described above, in the object detection device according to the present invention, the object determination unit receives the indirect wave as well as the case where the direct wave is received and triangulation is possible, and the first transmission / reception unit and the second transmission / reception unit receive the indirect wave. Even in the case, the total for judgment is increased by the second reliability. Thus, the object detection apparatus can determine the presence of an object by using an indirect wave when only an indirect wave can be received.

  In the object detection device according to the present invention described above, the object determination unit indicates that the determination result indicates that both the first transmission / reception unit and the second transmission / reception unit have received the indirect wave, and based on the determination result If it is determined that the triangulation is not established, the second reliability may be added to the judgment sum.

  As described above, in the object detection device of the present invention, when the object determination unit determines that triangulation is established, the first reliability is added to the total for determination, and when it is determined that triangulation is not established, the second reliability is determined. Add the degree to the judgment sum. As a result, the object detection apparatus can suppress the addition of the first reliability and the second reliability to the total for determination at one time, and can improve the determination accuracy of the presence of the object.

  In the object detection device of the present invention described above, the object determination unit may determine the presence of the object based on the total for determination when it is determined that the triangulation is established.

  As described above, in the object detection device of the present invention, the object determination unit determines the presence of an object when triangulation where a direct wave can be received is established, so that the object detection device detects an object with higher accuracy. Presence determination can be performed. Further, in the object detection device, even when the object determination unit determines that triangulation is not established, the second reliability is added to the sum for determination, so that when triangulation is established, the second reliability is already added. The presence of an object can be determined in a short time based on the total for determination.

  In the object detection device of the present invention described above, in the object determination unit, the determination result is that both the first transmission / reception unit and the second transmission / reception unit receive the indirect wave and receive the direct wave. If not, the second reliability may be added to the judgment sum.

  As described above, in the object detection device according to the present invention, when the object determination unit determines that triangulation is established, the first reliability is added to the determination sum, and both the first transmission / reception unit and the second transmission / reception unit are indirect. If a wave is received and a direct wave is not received, the second reliability is added to the judgment sum. As a result, the object detection apparatus can suppress the addition of the first reliability and the second reliability to the total for determination at one time, and can improve the determination accuracy of the presence of the object. Further, in the object detection apparatus, when both of the first transmission / reception unit and the second transmission / reception unit do not receive the direct wave, the position of the object is not on the transmission direction of the exploration wave of the first transmission / reception unit and the second transmission / reception unit. That is, it can be determined between the first transmission / reception unit and the second transmission / reception unit. Therefore, when the object detection device determines the presence of the object by adding the second reliability to the total for determination, the object detection device can determine that the position of the object is between the first transmission / reception unit and the second transmission / reception unit.

  In the object detection device of the present invention described above, the object determination unit may calculate the total for determination based on the first reliability and the second reliability that is less than or equal to the first reliability.

  Thus, the object detection device of the present invention can determine the presence of an object by emphasizing the first reliability when triangulation is established.

  In the object detection device of the present invention described above, the search wave determination unit is disposed on both sides outside the first transmission / reception unit and the second transmission / reception unit, and the third transmission / reception unit and the fourth transmission / reception unit transmit / receive the search wave. And determining whether the third transmission / reception unit and the fourth transmission / reception unit have received the indirect wave, based on transmission / reception information on the search wave acquired from the unit, and the object determination unit determines whether the determination result is It indicates that both the first transmission / reception unit and the second transmission / reception unit have received the indirect wave, and that both the third transmission / reception unit and the fourth transmission / reception unit have not received the indirect wave When it shows, you may add the said 2nd reliability to the said sum for judgment.

  As described above, in the object detection device of the present invention, the object determination unit adds the second reliability to the total for determination when the outer third transmission / reception unit and the fourth transmission / reception unit do not receive the indirect wave. Thus, in the object detection apparatus, an object is present between the first transmission / reception unit and the second transmission / reception unit in which the third transmission / reception unit and the fourth transmission / reception unit do not easily receive indirect waves even when triangulation is not established. It can be determined.

FIG. 1 is a plan view of a vehicle equipped with a plurality of transmitting and receiving units of the object detection system according to the first embodiment. FIG. 2 is a block diagram showing the configuration of an object detection system. FIG. 3 is a functional block diagram for explaining the function of the object detection apparatus. FIG. 4 is a plan view of the rear side of the vehicle for explaining detection / non-detection of a distant object by a search wave. FIG. 5 is a graph illustrating a survey wave reflected and received by a distant object. FIG. 6 is a plan view on the rear side of the vehicle for explaining detection / non-detection of an object in the vicinity by a search wave. FIG. 7 is a graph illustrating a search wave reflected and received by an object in the vicinity. FIG. 8 is a graph showing the relationship between threshold wave height and transmission / reception time. FIG. 9 is a flowchart of an object detection process of the first embodiment performed by the processing unit. FIG. 10 is a flowchart of an object detection process of the second embodiment performed by the processing unit. FIG. 11 is a flowchart of an object detection process of the third embodiment performed by the processing unit.

  The same components as those in the following exemplary embodiments and the like will be denoted by the same reference numerals, and overlapping descriptions will be appropriately omitted.

First Embodiment
FIG. 1 is a plan view of a vehicle 10 on which a plurality of transmission / reception units 14Fa, 14Fb,... Of the object detection system according to the first embodiment are mounted. The direction indicated by the arrow in FIG. 1 is taken as the front-rear and left-right direction of the vehicle 10.

  As shown in FIG. 1, a plurality of transmission / reception units 14Ra, 14Rb, 14Rc, 14Rd, 14Fa, 14Fb, 14Fc, 14Fd are provided on the outer peripheral portion of the vehicle 10. When it is not necessary to distinguish the transmitting and receiving unit 14, the transmitting and receiving units 14R, 14F, 14 and the like are described. The transmission / reception unit 14 transmits / receives a survey wave to the periphery to detect an object around the vehicle 10, and outputs transmission / reception information regarding transmission / reception of the survey wave.

  For example, four transmitting and receiving units 14Ra, 14Rb, 14Rc, and 14Rd are provided at the rear end of the vehicle body 12 at regular intervals in the left-right direction. Specifically, the transmission / reception units 14Rb and 14Rc are disposed at the center in the left-right direction, and the transmission / reception units 14Ra and 14Rd are disposed on both sides outside the transmission / reception units 14Rb and 14Rc. The transmission / reception units 14Rb and 14Rc are examples of the first transmission / reception unit and the second transmission / reception unit. Four other transmission / reception units 14Fa, 14Fb, 14Fc, 14Fd are provided at the front end of the vehicle body 12 of the vehicle 10 at regular intervals along the left-right direction. Specifically, the transmitting and receiving units 14Fb and 14Fc are disposed at the center in the horizontal direction, and the transmitting and receiving units 14Fa and 14Fd are disposed on both sides outside the transmitting and receiving units 14Fb and 14Fc.

  The transmission and reception unit 14 is, for example, a sensor or a sonar that transmits a search wave such as an ultrasonic wave. For example, the transmission and reception unit 14R transmits the search wave to the rear. The transmission and reception unit 14F transmits the search wave forward. Each transmitting / receiving unit 14 may transmit the search wave in a direction inclined in the left-right direction (for example, the outer side) of the rear or the front. Each transmission / reception unit 14 transmits the survey wave while shifting time. For example, the transmission / reception units 14Ra and 14Rd transmit the search wave first, and then the transmission / reception unit 14Rb transmits the search wave with a predetermined time (hereinafter referred to as transmission interval), and the transmission / reception unit 14Rc further transmits the transmission interval. Sends a survey wave. The transmission interval may be appropriately set as long as it is longer than the minimum transmission / reception time of the search wave required to detect an object within the detection range. The transmitting and receiving unit 14 receives a survey wave reflected by an object. Here, the transmission / reception unit 14 transmits a search wave (hereinafter, referred to as a direct wave) transmitted by itself and a search wave transmitted by another transmission / reception unit 14 and reflected by an object (hereinafter referred to as an indirect wave). To receive). The transmission / reception unit 14 outputs transmission / reception information including information on the transmission time transmitted by itself, the reception time at which the survey wave was received, and the height of the received survey wave.

  FIG. 2 is a block diagram showing the configuration of the object detection system 16. The object detection system 16 detects an object such as an obstacle around the vehicle 10, and outputs information of the detected object to a braking system 90 including a braking unit 92 such as a brake, thereby allowing the vehicle 10 to communicate with the object. Avoid collisions. As shown in FIG. 2, the object detection system 16 includes a plurality of transmission / reception units 14, an object detection device 20, and an in-vehicle network 22.

  The plurality of transmitting and receiving units 14 are connected to the in-vehicle network 22. The plurality of transmission / reception units 14 transmit transmission / reception information to the object detection apparatus 20 via the in-vehicle network 22.

  The object detection apparatus 20 determines the presence of an object and the position of the object based on the transmission time, the reception time, and the wave height indicated by transmission / reception information acquired from each of the plurality of transmission / reception units 14. The object detection device 20 outputs information on the detected object to the braking unit control unit 94 or the like to suppress the collision of the vehicle 10.

  The object detection device 20 is a computer including a microcomputer such as an ECU (Electronic Control Unit). The object detection device 20 includes a central processing unit (CPU) 20a, a read only memory (ROM) 20b, a random access memory (RAM) 20c, and a solid state drive (SSD) 20f. The CPU 20a, the ROM 20b and the RAM 20c may be integrated in the same package.

  The CPU 20a is an example of a hardware processor, reads a program stored in a non-volatile storage device such as the ROM 20b, and executes various arithmetic processing and control according to the program.

  The ROM 20 b stores each program and parameters necessary for the execution of the program. The RAM 20 c temporarily stores various data used in the calculation by the CPU 20 a. The SSD 20 f is a rewritable non-volatile storage device, and maintains data even when the object detection device 20 is powered off.

  The in-vehicle network 22 is, for example, a CAN (Controller Area Network). The in-vehicle network 22 electrically connects the plurality of transmission / reception units 14, the object detection device 20, and the braking unit control unit 94 to each other so as to transmit and receive signals and information.

  The braking system 90 includes a braking unit 92 and a braking unit control unit 94.

  The braking unit control unit 94 is a computer such as an ECU. The braking unit control unit 94 is connected to the in-vehicle network 22. The braking unit control unit 94 is connected to a braking unit 92 such as a brake so as to be able to transmit information. The braking unit control unit 94 acquires object information regarding the position or presence of an object around the vehicle 10 detected by the object detection device 20 via the in-vehicle network 22. The braking unit control unit 94 transmits a control signal to the braking unit 92 to control based on the acquired object information.

  FIG. 3 is a functional block diagram for explaining the function of the object detection device 20. As shown in FIG. As shown in FIG. 3, the object detection device 20 includes a processing unit 24 and a storage unit 26.

  The processing unit 24 is realized, for example, as a function of the CPU 20a. The processing unit 24 includes a search wave determination unit 30 and an object determination unit 32. The processing unit 24 may function as the search wave determination unit 30 and the object determination unit 32 by, for example, reading the object detection program 34 stored in the storage unit 26. Part or all of the search wave determination unit 30 and the object determination unit 32 may be configured by hardware such as a circuit including an application specific integrated circuit (ASIC) or a field-programmable gate array (FPGA).

  The search wave determination unit 30 determines whether the search wave received by each of the transmission / reception units 14 is a direct wave or an indirect wave based on the transmission / reception information acquired from the transmission / reception unit 14. Specifically, the search wave determination unit 30 transmits and receives transmission time of the search wave transmitted by itself, the reception time when the search wave is received, and transmission / reception information indicating the wave height which is the strength of the received search wave. Get from If the reception time of any of the transmission / reception units 14 is within a predetermined determination time (for example, transmission interval) from the transmission time of one of the transmission / reception units 14, the search wave determination unit 30 directly transmits the search waves received by the transmission / reception unit 14 It may be determined as a wave, and the survey wave received by the other transmission / reception units 14 may be determined as an indirect wave. The determination time is longer than the transmission interval between one transmission / reception unit 14 and another transmission / reception unit 14. In other words, the other transmission / reception unit 14 does not transmit the search wave during the time from the transmission time when one of the transmission / reception units 14 transmits the search wave to the determination time. The search wave determination unit 30 may control the transmission interval by outputting an instruction signal for transmitting the search wave to each of the transmission / reception units 14. When the search wave determination unit 30 acquires the transmission and reception information from all the transmission and reception units 14, the transmission and reception information is sent to the object determination unit 32 together with the determination result of determining whether the search wave received by each transmission and reception unit 14 is a direct wave or an indirect wave. Output.

  The object determination unit 32 determines the presence of an object in the vicinity of the vehicle 10 based on the determination result and the transmission / reception information acquired from the search wave determination unit 30. Specifically, the object determining unit 32 determines, based on the determination result, the first reliability when it is determined that triangulation is established, and the second reliability when both of the transmitting and receiving units 14Rb and 14Rc receive an indirect wave. The total for determination, which is the sum of degrees, is calculated, and the presence of an object is determined based on the total for determination. For example, when the determination result indicates that one transmitting / receiving unit 14R of the pair of adjacent transmitting / receiving units 14Rb and 14Rc receives a direct wave and the other transmitting / receiving unit 14R receives an indirect wave, an object The determination unit 32 determines that triangulation is established based on the determination result, and adds the first reliability to the determination sum. The object determination unit 32 may add the first reliability to the determination sum, in addition to the above conditions, when the wave heights of the direct wave and the indirect wave are equal to or more than the threshold wave height. On the other hand, when the determination result indicates that both of the pair of transmitting and receiving units 14Rb and 14Rc do not receive the direct wave and that the indirect wave is received, the object determining unit 32 determines that triangulation is not established. The determination is made and the second reliability is added to the determination sum. In addition to the above conditions, the object determining unit 32 performs the second reliability when the wave height of the indirect wave is equal to or higher than the threshold wave height and both of the adjacent transmitting and receiving units 14Rb and 14Rc do not receive the direct wave. The degree may be added to the judgment sum. The first reliability and the second reliability may be predetermined numerical values, and may be stored in the storage unit 26 as part of the numerical data 36. The second reliability is, for example, less than or equal to the first reliability. For example, when the first reliability is "3", the second reliability may be a numerical value of 3 or less and 1 or more.

  The object determining unit 32 determines that an object is present when the determination sum is equal to or higher than the threshold reliability. The threshold reliability may be a predetermined numerical value, and may be stored in the storage unit 26 as a part of the numerical data 36. The threshold reliability may be, for example, a numerical value of 10 or more and 15 or less. When the object determination unit 32 determines that an object is present, the object determination unit 32 outputs a determination result to the effect that the object is present to the braking unit control unit 94 via the in-vehicle network 22.

  The storage unit 26 stores a program executed by the processing unit 24 and data necessary for executing the program. For example, the storage unit 26 stores an object detection program 34 that the processing unit 24 executes. The storage unit 26 stores numerical data 36 including the reliability, the threshold, the determination time, and the like necessary for the execution of the object detection program 34.

  When the braking unit control unit 94 acquires from the object determining unit 32 the determination result that the object is determined from the object determining unit 32, the braking unit control unit 94 controls the braking unit 92 to stop the vehicle 10.

  FIG. 4 is a plan view of the rear side of the vehicle 10 for explaining detection / non-detection of a distant object OJ by a search wave. FIG. 5 is a graph for explaining a survey wave received by being reflected by a distant object OJ. FIG.4 and FIG.5 is a figure in case the distance of the vehicle 10 and the object OJ is long. The object OJ is disposed at a position 2 m from the rear end of the vehicle body 12.

  In FIG. 4, a two-dot chain line indicates the path of the search wave. An alternate long and short dash line indicates the center CE of the vehicle body 12 in the left-right direction. The vehicle width which is the width | variety of the left-right direction of the vehicle 10 is Wacm (for example, 73 cm). The transmitting and receiving units 14Rb and 14Rc are disposed at a position Pacm (for example, 23 cm) from the center CE of the vehicle body 12. The transmitting and receiving units 14Ra and 14Rd are disposed at a position Pbcm (for example, 62 cm) from the center CE of the vehicle body 12. The center CE of the vehicle body 12 is at the same position as the center of the object OJ in the left-right direction. The width in the left-right direction of the object OJ is a wall of Wbcm (for example, 40 cm). Here, 2 × Wa <Wb. Accordingly, the object OJ is disposed between the transmitting and receiving units 14Rb and 14Rc in the left-right direction.

  The vertical axis in FIG. 5 indicates the strength of the received survey wave. The left figure of FIG. 5 shows the intensity of the reception of the direct wave, and the right figure shows the intensity of the reception of the indirect wave.

Each symbol of the horizontal axis in the left diagram of FIG. 5 is as follows.
W1a: A direct wave received by the transmission / reception unit 14Ra.
W1b: A direct wave received by the transmission / reception unit 14Rb.
W1c: A direct wave received by the transmission / reception unit 14Rc.
W1d: A direct wave received by the transmission / reception unit 14Rd.

Each symbol of the horizontal axis of the right figure of FIG. 5 is as follows.
W2a: An indirect wave transmitted by the transmission / reception unit 14Ra and received by the transmission / reception unit 14Rb.
W2b: An indirect wave transmitted by the transmission / reception unit 14Rb and received by the transmission / reception unit 14Ra.
W2c: An indirect wave transmitted by the transmission / reception unit 14Rb and received by the transmission / reception unit 14Rc.
W2d: An indirect wave transmitted by the transmission / reception unit 14Rc and received by the transmission / reception unit 14Rb.
W2e: An indirect wave transmitted by the transmission / reception unit 14Rc and received by the transmission / reception unit 14Rd.
W2f: An indirect wave transmitted by the transmission / reception unit 14Rd and received by the transmission / reception unit 14Rc.

  As shown in FIGS. 4 and 5, when the distance between the vehicle body 12 and the object OJ is 2 m, the transmission / reception unit 14Rb receives an indirect wave which is a survey wave transmitted by the transmission / reception unit 14Rc. The transmission / reception unit 14Rc receives an indirect wave which is a survey wave transmitted by the transmission / reception unit 14Rb. The transmitting and receiving units 14Rb and 14Rc do not receive the direct wave which is the search wave transmitted by itself. The transmitting / receiving units 14Ra and 14Rd provided at the corners of the vehicle body 12 receive direct waves, but the transmitting / receiving units 14Rb and 14Rc do not receive the search waves transmitted by the transmitting / receiving units 14Ra and 14Rd as indirect waves. The direct waves received by the transmitting and receiving units 14Ra and 14Rd are highly likely to be survey waves reflected by the road surface. Therefore, detection of the object OJ by the direct wave is unreliable. Moreover, although transmission / reception part 14Ra is receiving an indirect wave, it is considered to be an indirect wave reflected by the road surface etc., and detection of the object OJ by the said indirect wave has low reliability. Therefore, the object determination unit 32 excludes the direct wave and the indirect wave according to the threshold wave height, so that even if the search wave is received, the reliability is not added to the determination sum.

  In the present embodiment, as shown in FIG. 4 and FIG. 5, when the transmitting / receiving units 14Rb and 14Rc receive the indirect wave and do not receive the direct wave, the object determining unit 32 determines the second reliability as a total for determining Add to

  FIG. 6 is a plan view on the rear side of the vehicle 10 for explaining detection / non-detection of an object OJ in the vicinity by a search wave. FIG. 7 is a graph for explaining a survey wave received by being reflected by a nearby object OJ. 6 and 7 are diagrams when the distance between the vehicle 10 and the object OJ is short. The object OJ is disposed 1 m from the rear end of the vehicle body 12. The situations of FIGS. 6 and 7 other than the distance between the object OJ and the vehicle body 12 are the same as those of FIGS. 4 and 5.

  As shown in FIGS. 6 and 7, when the distance between the vehicle body 12 and the object OJ is 1 m, the transmitting and receiving unit 14Rb receives the direct wave which is the exploration wave transmitted by itself and the transmitting and receiving unit 14Rc transmits Receive an indirect wave, which is a survey wave. The transmitting and receiving unit 14Rc receives a direct wave that is a probe wave transmitted by itself and also receives an indirect wave that is a probe wave transmitted by the transmitting and receiving unit 14Rb. In this case, the object determination unit 32 determines that triangulation is established.

  The transmitting / receiving units 14Ra and 14Rd provided at the corners of the vehicle body 12 receive direct waves, but the transmitting / receiving units 14Rb and 14Rc do not receive the search waves transmitted by the transmitting / receiving units 14Ra and 14Rd as indirect waves. The direct wave is likely to be a survey wave reflected by the road surface. Therefore, detection of the object OJ by the direct wave is unreliable. Moreover, although transmission / reception part 14Ra is receiving an indirect wave, it is considered to be an indirect wave reflected by the road surface etc., and detection of the object OJ by the said indirect wave has low reliability. Therefore, the object determination unit 32 eliminates these direct waves and indirect waves by the threshold wave height, and does not add reliability to the determination sum even if these exploration waves are received.

  In this embodiment, as shown in FIGS. 6 and 7, when one of the transmission / reception units 14Rb and 14Rc receives a direct wave and the other of the transmission / reception units 14Rb and 14Rc receives an indirect wave, an object is obtained. The determination unit 32 determines that triangulation is established, and adds the first reliability to the total for determination.

  FIG. 8 is a graph showing the relationship between threshold wave height and transmission / reception time. The vertical axis | shaft of FIG. 8 shows the threshold-value wave height which determines the intensity | strength of the survey wave which the transmission / reception part 14 received. The threshold wave height shown in FIG. 8 is a threshold wave height of an indirect wave. The horizontal axis indicates the transmission / reception time of the survey wave transmitted / received by the transmission / reception unit 14. The transmission / reception time is associated with the distance to the object OJ. The threshold wave height shown in FIG. 8 may be a value set in advance by measuring the reception condition of the search wave by the object OJ shown in FIG. 4 and the like.

  As shown in FIG. 8, the threshold wave height changes with the transmission and reception time. Specifically, the threshold wave height has two peaks Pk1 and Pk2. The first peak Pk1 has a maximum value at a transmission / reception time of approximately "0". Thereby, the object determination unit 32 discards the received survey wave based on the first peak Pk1 after being reflected by the road surface almost directly below the transmission / reception unit 14 that has transmitted the survey wave. The second peak Pk2 has a maximum value in transmission and reception time corresponding to a distance of several tens cm. Thus, the object determination unit 32 determines the received survey wave based on the second peak Pk2 after being reflected by the speed breaker, the speed bump, the wheel stopper, etc. existing on the road surface several tens cm away from the vehicle 10 Discard. The threshold wave height has a constant value at a distance greater than or equal to the transmission / reception time T. Thereby, the object determination unit 32 excludes a wave from a distance that is considered to be noise. The threshold wave height of the direct wave may have the same shape as that of the threshold wave height shown in FIG. 8 and different in scale.

  FIG. 9 is a flowchart of the object detection process of the first embodiment performed by the processing unit 24. The processing unit 24 executes an object detection process by reading the object detection program 34 stored in the storage unit 26. In addition, although the object detection process in case the transmission / reception part 14R transmits a survey wave is demonstrated, the process in the case where the transmission / reception part 14F transmits a survey wave is also the same.

  As shown in FIG. 9, in the object detection process, the search wave determination unit 30 acquires transmission / reception information including information on the transmission time, reception time, and wave height of the search wave from each transmission / reception unit 14R (S102). The transmission / reception information acquired here is information on all the survey waves received after all the transceivers 14Ra, 14Rb, 14Rc, and 14Rd transmit the survey waves in order.

  The search wave determination unit 30 determines whether the search wave received by each of the transmission / reception units 14R is a direct wave or an indirect wave based on the transmission / reception information (S104). For example, if the transmission / reception time from the transmission time when one of the transmission / reception units 14R transmits the investigation wave to the reception time is within the judgment time, the investigation wave judgment unit 30 receives the transmission / reception unit 14R which transmitted the investigation wave. It may be determined that the detected survey wave is a direct wave, and the other survey waves received by the other transmission / reception unit 14R may be determined as an indirect wave. The search wave determination unit 30 outputs the determination result as to whether the search wave is a direct wave or an indirect wave to the object determination unit 32 together with transmission / reception information.

  The object determination unit 32 determines whether triangulation is established based on the determination result acquired from the exploration wave determination unit 30 (S106). The object determination unit 32 determines that triangulation is established, for example, when the transmission / reception unit 14Rb receives a direct wave and the transmission / reception unit 14Rc adjacent to the transmission / reception unit 14Rb receives a direct wave or an indirect wave. Otherwise, it is determined that triangulation is not established.

  When the object determination unit 32 determines that triangulation is established (S106: Yes), the object determination unit 32 determines whether the wave height of the direct wave and the indirect wave used for triangulation is equal to or more than the threshold wave height (S108). If the object determination unit 32 determines that the wave heights of both the direct wave and the indirect wave used for triangulation are equal to or higher than the threshold wave height (S108: Yes), the first reliability is added to the judgment sum (S110), and step S120 is performed. Run. If the object determination unit 32 determines that any of the wave heights of the direct wave and the indirect wave used for triangulation is not the threshold wave height or more (S108: No), the process proceeds to step S120 without adding the first reliability to the judgment sum. Run.

  On the other hand, when the object determining unit 32 determines that triangulation is not established (S106: No), both of the pair of transmitting and receiving units 14R (for example, transmitting and receiving units 14Rb and 14Rc) are indirect waves based on the transmission and reception information. It is determined whether it has been received (S111). When the object determination unit 32 determines that at least one of the transmission / reception units 14Rb and 14Rc does not receive an indirect wave (S111: No), it executes step S120.

  If the object determination unit 32 determines that both of the transmitting and receiving units 14Rb and 14Rc have received the indirect wave (S111: Yes), whether the wave heights of both of the indirect waves received by the transmitting and receiving units 14Rb and 14Rc are equal to or more than the threshold wave height. It determines (S112). When it is determined that the wave height of any of the indirect waves is not the threshold wave height or more (S112: No), the object determination unit 32 executes step S120.

  If the object determination unit 32 determines that both wave heights of the indirect wave are equal to or greater than the threshold wave height (S112: Yes), the object determination unit 32 determines whether any one of the transmission / reception units 14Rb and 14Rc receives the direct wave (S114). ). When it is determined that one of the transmission / reception units 14Rb and 14Rc receives the direct wave (S114: Yes), the object determination unit 32 executes step S120. If the object determination unit 32 determines that both of the transmission / reception units 14Rb and 14Rc do not receive the direct wave (S114: No), the second reliability is added to the determination sum (S116), and step S120 is executed. .

  The object determination unit 32 determines whether the total for determination is equal to or higher than the threshold reliability (S120). When the object determination unit 32 determines that the total for determination is not the threshold reliability or more (S120: No), it determines that the presence of the object OJ is unconfirmed (S122), and the processing unit 24 performs step S102 and subsequent steps. repeat.

  When the object determination unit 32 determines that the total for determination is equal to or higher than the threshold reliability (S120: Yes), the total for determination is reset, and the presence of the object OJ is determined (S124). Certain object information is output to the braking unit control unit 94 and the like (S126). Here, when triangulation is established, the object determination unit 32 executes triangulation to specify the position of the object OJ, and controls the braking unit using the position of the object OJ as object information, together with the effect that the object OJ exists. You may output to part 94 grade | etc.,. Further, when triangulation is not established, the object determination unit 32 does not receive the direct wave by both of the transmitting and receiving units 14Rb and 14Rc, so the position of the object OJ is not on the transmission direction of the search wave of the transmitting and receiving units 14Rb and 14Rc. That is, it can be determined that it is between the transmission / reception units 14Rb and 14Rc. In this case, the object determination unit 32 may output that the position of the object OJ is between the transmission / reception units 14Rb and 14Rc as object information to the braking unit control unit 94 or the like, together with the fact that the object OJ is present. When acquiring the object information, the braking unit control unit 94 controls the braking unit 92 according to the position or the like of the object OJ to decelerate and stop the vehicle 10. Thereafter, the processing unit 24 repeats step S102 and subsequent steps.

  As described above, in the object detection apparatus 20 according to the first embodiment, the object determination is performed not only when the direct wave is received and triangulation is established, but also when both of the transmitting and receiving units 14Ra and 14Rb receive the indirect wave. The part 32 increases the total for judgment by the second reliability. As a result, the object detection apparatus 20 uses indirect waves even when it can not receive direct waves and can only receive indirect waves because the width of the object OJ is narrower than the distance between the transmitting and receiving units 14 like a pole or a pole. Thus, the presence of the object OJ can be determined. As a result, the object determination unit 32 can detect an object OJ whose width is narrower than that between adjacent transmission / reception units 14 even from a distance.

  In the object detection device 20, when the object determination unit 32 determines that triangulation is established, the first reliability is added to the total for determination, and it is determined that triangulation is not established, and adjacent transmission / reception units 14Rb and 14Rc If both of them receive the indirect wave, the second reliability is added to the judgment sum. Thereby, the object detection apparatus 20 can improve the determination accuracy of the presence of the object OJ by suppressing the addition of the first reliability and the second reliability to the total for determination at one time.

  In the object detection device 20, when the object determination unit 32 determines that triangulation is established, the first reliability is added to the total for determination, and both of the adjacent transmission / reception units 14Rb and 14Rc do not receive the direct wave. , The second reliability is added to the sum for judgment. Thereby, the object detection apparatus 20 can improve the determination accuracy of the presence of the object OJ by suppressing the addition of the first reliability and the second reliability to the total for determination at one time. Further, the object detection apparatus 20 can determine that the object OJ is present between the transmission and reception units 14Rb and 14Rc because both of the adjacent transmission and reception units 14Rb and 14Rc do not receive the direct wave.

  In the object detection device 20, the object determination unit 32 calculates the total for determination based on the first reliability and the second reliability not higher than the first reliability. Thereby, the object detection apparatus 20 can determine the presence of the object OJ by placing importance on the reliability when triangulation is established.

Second Embodiment
An object detection apparatus 20 according to a second embodiment in which a part of the above-described first embodiment is modified will be described.

  The object determination unit 32 according to the second embodiment determines the presence of the object OJ based on the total for determination when it is determined that triangulation is established. On the other hand, the object determination unit 32 adds the second reliability to the determination sum if it is determined that both the transmitting and receiving units 14Rb and 14Rc have received an indirect wave, but if it is determined that triangulation is not established, the presence of the object OJ Do not judge Therefore, the object determination unit 32 does not determine the presence of the object OJ when it is determined that triangulation is not established even if the total for determination is equal to or higher than the threshold reliability.

  FIG. 10 is a flowchart of an object detection process of the second embodiment that the processing unit 24 executes. Among the steps of the object detection process of the second embodiment, the description of the same steps as the object detection process of the first embodiment will be omitted or simplified.

  As shown in FIG. 10, in the object detection process of the second embodiment, when the object determination unit 32 determines that triangulation is not established (S106: No), the pair of transmitting / receiving units 14R adjacent to each other based on transmission / reception information It is determined whether (for example, both of the transmission / reception units 14Rb and 14Rc) have received an indirect wave (S211). If the object determination unit 32 determines that at least one of the transmission / reception units 14Rb and 14Rc does not receive an indirect wave (S211: No), it returns to step S102 and executes it.

  If the object determination unit 32 determines that both of the transmitting and receiving units 14Rb and 14Rc receive the indirect wave (S211: Yes), whether the wave heights of both of the indirect waves received by the transmitting and receiving units 14Rb and 14Rc are equal to or more than the threshold wave height It determines (S212). If the object determination unit 32 determines that any wave height of the indirect wave is not the threshold wave height or more (S212: No), the process returns to step S102 and is executed.

  If the object determination unit 32 determines that the wave height of the indirect wave is equal to or greater than the threshold wave height (S212: Yes), the object determination unit 32 determines whether any one of the transmission / reception units 14Rb and 14Rc receives the direct wave (S214). When the object determination unit 32 determines that one of the transmission / reception units 14Rb and 14Rc receives the direct wave (S214: Yes), the object determination unit 32 returns to Step S102 and executes. If the object determination unit 32 determines that both of the transmission / reception units 14Rb and 14Rc do not receive the direct wave (S214: No), the second reliability is added to the determination sum (S216), and the process returns to step S102. Run.

  On the other hand, when the object determination unit 32 determines that triangulation is established (S106: Yes), it determines whether the total for determination, which is the sum of the first reliability and the second reliability, is equal to or higher than the threshold reliability. After (S120), steps S122 and S124 and subsequent steps are executed.

  As described above, in the object detection device 20 according to the second embodiment, when the object determination unit 32 determines that triangulation is not established, the triangulation does not determine whether the total for determination is equal to or higher than the threshold reliability. Only when it is determined that the condition is satisfied, it is determined whether the determination sum is greater than or equal to the threshold reliability. That is, since the object determination unit 32 determines that the object OJ is present only when the triangulation that can receive the direct wave is established, the object detection device 20 according to the second embodiment has the object OJ with higher accuracy. A decision can be made. As a result, the braking unit control unit 94 can more appropriately control the braking unit 92 to stop the vehicle 10.

  In addition, even when the object determination unit 32 determines that triangulation is not established, the second reliability is added to the determination sum, so that when triangulation is established, the determination total to which the second reliability is already added The presence of the object OJ can be determined in a short time based on

Third Embodiment
An object detection apparatus 20 according to a third embodiment in which a part of the first embodiment described above is modified will be described.

  In the object determination unit 32 of the third embodiment, the determination result of the search wave determination unit 30 indicates that both of the transmission and reception units 14Rb and 14Rc do not receive the direct wave, and both of the transmission and reception units 14Ra and 14Rd are If it indicates that the indirect wave is not received, the second reliability is added to the judgment sum. The transmitting and receiving units 14Ra and 14Rd are examples of the third transmitting and receiving unit and the fourth transmitting and receiving unit.

  FIG. 11 is a flowchart of an object detection process of the third embodiment that the processing unit 24 executes. Descriptions of steps of the object detection process of the third embodiment that are similar to the steps of the object detection process of the first embodiment will be omitted or simplified.

  As shown in FIG. 11, in the object detection process of the third embodiment, when the object determination unit 32 determines that triangulation is not established (S106: No), a pair of adjacent transmission / reception units 14R is based on transmission / reception information. It is determined whether (for example, both of the transmission / reception units 14Rb and 14Rc) have received an indirect wave (S111). When the object determination unit 32 determines that at least one of the transmission / reception units 14Rb and 14Rc does not receive an indirect wave (S111: No), it executes step S120.

  If the object determination unit 32 determines that both of the transmitting and receiving units 14Rb and 14Rc have received the indirect wave (S111: Yes), whether the wave heights of both of the indirect waves received by the transmitting and receiving units 14Rb and 14Rc are equal to or more than the threshold wave height. It determines (S112). When it is determined that the wave height of any of the indirect waves is not the threshold wave height or more (S112: No), the object determination unit 32 executes step S120.

  If the object determination unit 32 determines that the wave height of the indirect wave is equal to or more than the threshold wave height (S112: Yes), it determines whether or not any of the adjacent pair of transmission / reception units 14Rb and 14Rc receives the direct wave. (S114). When the object determination unit 32 determines that both of the transmission / reception units 14Rb and 14Rc do not receive the direct wave (S114: No), one of the transmission / reception units 14Ra and 14Rd receives the indirect wave based on the transmission / reception information. It is determined whether or not there is (S315).

  When the object determination unit 32 determines that any of the transmission / reception units 14Ra and 14Rd receives an indirect wave (S315: Yes), the object determination unit 32 executes Step S120 without adding the second reliability to the determination sum. If the object determination unit 32 determines that both of the transmission / reception units 14Ra and 14Rd do not receive the indirect wave (S315: No), the second reliability is added to the determination sum (S116), and step S120 is executed. .

  Thereafter, the object determining unit 32 determines whether the total amount for determination is equal to or higher than the threshold reliability (S120), and then executes steps S122 and S124 and the subsequent steps.

  As described above, in the object detection device 20 of the third embodiment, the object determination unit 32 adds the second reliability to the total for determination when the transmission / reception units 14Ra and 14Rd do not receive the indirect wave. Thereby, even when triangulation is not established, the object determination unit 32 can determine that the object OJ is present between the transmission / reception units 14Rb and 14Rc in which the transmission / reception units 14Ra and 14Rd are difficult to receive indirect waves. .

  The functions, connection relationships, number, arrangement, and the like of the configurations of the respective embodiments described above may be appropriately changed or deleted within the scope of the invention and the scope of the invention and the equivalent scope. You may combine each embodiment suitably. The order of each step of each embodiment may be changed as appropriate.

  Although the above-mentioned embodiment gave the example which threshold wave height changes with transmitting and receiving time (or distance), threshold wave height is not limited to this. For example, the threshold wave height may be constant regardless of transmission / reception time (or distance).

  In the above-mentioned embodiment, although the object detection apparatus 20 provided in the vehicle 10 was mentioned as the example and demonstrated, the object detection apparatus 20 is not limited to this. For example, the object detection device 20 may be provided in another mobile unit having a drive source, such as an airplane, a ship, a two-wheel vehicle, etc., or may be provided in an apparatus other than the mobile unit.

  In the above-described embodiment, the object determination unit 32 determines that triangulation is established when one of the adjacent pair of transmission / reception units 14R receives the direct wave and the other receives the indirect wave. An example is given, but the situation where it is determined that triangulation is established is not limited to this. For example, the object determination unit 32 may determine that triangulation is established when both of the adjacent pair of transmission / reception units 14R (or pair of transmission / reception units 14F) receive the direct wave.

  In the above embodiment, the transmitter / receivers 14Rb and 14Rc are described as an example in which the first transmitter / receiver and the second transmitter / receiver are described, but the transmitters / receivers 14Ra and 14Rd function as the first transmitter / receiver and the second transmitter / receiver It is also good. The transceivers 14Fa, 14Fb, 14Fc, and 14Fd may function as the first transceiver and the second transceiver. The transceivers 14Fb and 14Fc may function as a first transceiver and a second transceiver, and the transceivers 14Fa and 14Fd may function as a third transceiver and a fourth transceiver.

14, 14F, 14Fa, 14Fb, 14Fc, 14Fd, 14R, 14Ra, 14Rb, 14Rc, 14Rd: transmission / reception unit, 16: object detection system, 20: object detection device, 30: exploration wave determination unit, 32: object determination unit, OJ: Object, Pk1: First peak, Pk2: Second peak.

Claims (6)

In order to detect an object, the first transmission / reception unit and the second transmission / reception unit are directly based on transmission / reception information regarding transmission / reception of the investigation wave acquired from the first transmission / reception unit and the second transmission / reception unit that transmit / receive a search wave around A search wave determination unit that determines whether a wave or an indirect wave has been received and outputs a determination result;
The first reliability when it is determined that triangulation is established based on the determination result, and the second reliability when both the first transmission / reception unit and the second transmission / reception unit receive the indirect wave An object determination unit that calculates a sum for determination that is a sum, and determines the presence of an object based on the sum for determination;
An object detection device comprising: When the object determination unit indicates that the determination result indicates that both the first transmission / reception unit and the second transmission / reception unit have received the indirect wave, and determines that the triangulation is not established based on the determination result, The object detection device according to claim 1, wherein the second reliability is added to the judgment sum. The object detection device according to claim 1, wherein the object determination unit determines the presence of the object based on the determination sum, when determining that the triangulation is established. When the object determination unit indicates that the determination result indicates that both the first transmission / reception unit and the second transmission / reception unit receive the indirect wave and the direct wave is not received, The object detection device according to any one of claims 1 to 3, wherein 2 reliability is added to the sum for determination. The said object determination part calculates the said sum total for determination based on the said 1st reliability and the said 2nd reliability below the said 1st reliability in any one of Claims 1-4. Object detection device. The search wave determination unit is disposed on both sides outside the first transmission / reception unit and the second transmission / reception unit, and transmits / receives information on the search wave acquired from a third transmission / reception unit that transmits / receives the search wave and a fourth transmission / reception unit It is determined whether the third transmission / reception unit and the fourth transmission / reception unit have received the indirect wave based on
The object determination unit indicates that the determination result indicates that both the first transmission / reception unit and the second transmission / reception unit have received the indirect wave, and both the third transmission / reception unit and the fourth transmission / reception unit The object detection apparatus according to any one of claims 1 to 5, wherein the second reliability is added to the judgment total sum when it indicates that the indirect wave is not received.

Images