Object detection apparatus

Abstract

To achieve detection in an optimum detection cycle by a transmission / reception part according to a vehicle state.SOLUTION: An object detection device includes: a first calculation unit which calculates a data acquisition request interval indicating a time interval of a data acquisition request on the basis of the number of operation transmission / reception sections which indicates the number of transmission / reception sections in operation and an upper limit number of TOFs which indicates an upper limit of the number of TOFs which can be acquired by one data acquisition request to each of a plurality of transmission / reception sections; and a second calculation unit which calculates a request timing which is a timing of the data acquisition request to each of the plurality of transmission / reception sections and a request number which is the number of times of issuing the data acquisition request to each of the plurality of transmission / reception sections so that a final data acquisition request can be issued just before the end of the minimum operation time of the transmission / reception sections based on a maximum distance to be detected on the basis of the data acquisition request interval.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an object detection device. [Background technology]

[0002] In an object detection device that uses ultrasound or the like to detect obstacles present around a vehicle, a technology is used in which multiple transmitter / receivers, such as sensors that transmit and receive ultrasound, are installed on the vehicle body, and the distance from the vehicle to an object such as an obstacle is calculated based on the timing of transmission and reception of ultrasound or the like at each transmitter / receiver.

[0003] For example, Patent Document 1 discloses a technology in which, in a system consisting of a master and multiple sensors as slaves controlled by the master, which are connected to the same bus line, the central unit (controller) acting as the master transmits a synchronization signal to the sensors, and each sensor transmits acquired data to the master at a predetermined transmission time in response to the synchronization signal. To achieve communication between the master control unit and the slave sensors, it is necessary to control the synchronization signal based on the timing and number of data acquisition requests from the master. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2020-532184 Summary of the Invention [Problem to be solved by the invention]

[0005] In vehicle sensors, the detection distance may be switched depending on the relative positions of the vehicle and obstacles, which affects the minimum operating time of the sensor. Furthermore, in vehicle sensors, the upper limit of the number of distance information received may change depending on the distance and characteristics of the object being detected, and the number of sensors operating may change depending on the shift position of the shift lever and the surrounding conditions of the vehicle. In such cases, the response time of the sensor may be affected.

[0006] In order to respond to all operating conditions of such vehicles and sensors, it is necessary to communicate with the sensors at a sensor operating time that is appropriate for the maximum detection distance, the maximum number of sensors, and the timing and number of data acquisition requests that correspond to the maximum number of distance information.

[0007] However, when the detection target distance is short, the time spent receiving unnecessary data increases, resulting in inefficient operation. Also, the detection period becomes long, making it difficult to obtain the detection performance required for vehicle control. As described above, with the conventional technology, it is difficult to operate the transmitter / receiver unit efficiently in accordance with various vehicle conditions, and as a result, it is difficult for the transmitter / receiver unit to perform detection at an optimal detection period.

[0008] The present invention has been made in view of the above, and has as its object to provide an object detection device that can realize detection at an optimum detection period by a transmitter / receiver depending on the vehicle situation. [Means for solving the problem]

[0009] The object detection device of the present invention is an object detection device mounted on a moving body and detects objects present in the vicinity of the moving body, and comprises a plurality of transceivers, each of which transmits a transmission wave and receives a reflected wave generated when the transmission wave is reflected by an object, and a control unit for controlling the plurality of transceivers, wherein the control unit comprises: a first calculation unit that calculates a data acquisition request interval, which indicates the time interval between the data acquisition requests, based on a number of operating transceivers, which indicates the number of operating transceivers, and an upper limit TOF number, which indicates the upper limit of the number of TOFs (Time of Flight) that can be acquired in one data acquisition request requesting acquisition of TOF from each of the plurality of transceivers; a second calculation unit that calculates, based on the data acquisition request interval, a request timing, which is the timing of the data acquisition request, and a request count, which is the number of times the data acquisition request is issued to each of the plurality of transceivers, so that the final data acquisition request can be issued just before the end of the minimum operating time of the transceiver based on the maximum distance to be detected; and an issuing unit that issues the data acquisition request to each of the plurality of transceivers, based on the request timing and the request count. [Effects of the Invention]

[0010] According to the object detection device of the present invention, it is possible to realize detection at an optimum detection period by the transmitting and receiving unit depending on the vehicle situation. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a vehicle according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of the configuration of a vehicle control system according to the embodiment. [Figure 3] FIG. 3 is a diagram showing an example of a method for calculating distance using the TOF method. [Figure 4] FIG. 4 is a diagram illustrating an example of a functional configuration of the object detection device according to the embodiment. [Figure 5]FIG. 5 is a diagram illustrating an example of calculation of the request timing of a data acquisition request and the number of requests in the embodiment. [Figure 6] FIG. 6 is a flowchart illustrating an example of a procedure for a data acquisition request control process according to the embodiment. [Figure 7] FIG. 7 is a schematic diagram showing an example in which the timing of a data acquisition request according to the embodiment is compared with the timing of a data acquisition request according to the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The configurations of the embodiments described below and the actions and effects brought about by the configurations are merely examples, and the present invention is not limited to the following description.

[0013] (Embodiment) (Vehicle 1 configuration) 1 is a diagram showing an example of the configuration of a vehicle 1 according to an embodiment. The vehicle 1 is an example of a moving body on which an object detection device according to the embodiment is mounted. The object detection device according to the embodiment is a device that detects obstacles present around the vehicle 1 based on information such as TOF (Time Of Flight) and Doppler shift acquired by transmitting and receiving ultrasonic waves.

[0014] The object detection device according to this embodiment includes a plurality of transceivers 21A to 21L. Hereinafter, when there is no need to distinguish between the plurality of transceivers 21A to 21L, they may be referred to as transceivers 21. Each transceiver 21 is installed on the vehicle body 2, which is the exterior of the vehicle 1, transmits ultrasonic waves toward the outside of the vehicle body 2, and receives ultrasonic waves generated when the ultrasonic waves are reflected by an object present 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.

[0015] 1, four transceivers 21A to 21D are arranged at the front end of the vehicle body 2, four transceivers 21E to 21H are arranged at the rear end, two transceivers 21I and 21J are arranged on the right side, and two transceivers 21K and 21L are arranged on the left side. Note that the number and installation positions of the transceivers 21 are not limited to this example.

[0016] (Configuration of vehicle control system 50) 2 is a diagram showing an example of the configuration of a vehicle control system 50 according to an embodiment. The vehicle control system 50 performs processing for controlling the vehicle 1 based on information output from the object detection device 200. The vehicle control system 50 according to this embodiment includes an ECU 100 and the object detection device 200.

[0017] The object detection device 200 includes a plurality of transmitter / receivers 21 and a control unit 220. Each transmitter / receiver 21 includes a vibrator 211 configured using a piezoelectric element or the like, an amplifier, etc., and realizes transmission and reception of ultrasonic waves by the vibration of the vibrator 211. Specifically, each transmitter / receiver 21 transmits ultrasonic waves generated in response to the vibration of the vibrator 211 as a transmission wave, and detects the vibration of the vibrator 211 caused by a wave reflected from the transmission wave by an object such as an obstacle O or the road surface. The vibration of the vibrator 211 is converted into an electrical signal, and based on the electrical signal, it is possible to obtain, for example, a time of flight (TOF) corresponding to the distance from the transmitter / receiver 21 to the obstacle O and Doppler shift information corresponding to the relative speed between the vehicle 1 and the obstacle O. Here, the control unit 220 acts as a master, while each of the transmitting and receiving units 21 acts as a slave.

[0018] 2 illustrates a configuration in which both transmission of the transmission wave and reception of the reflected wave are performed using a single oscillator 211, but the configuration of the transmitter / receiver 21 is not limited to this. For example, the transmitter and receiver may be separated, such as a configuration in which an oscillator for transmitting the transmission wave and an oscillator for receiving the reflected wave are separately provided.

[0019] The control unit 220 includes an input / output device 221, a storage device 222, and a processor 223. The input / output device 221 is an interface device that enables transmission and reception of information between the control unit 220 and external devices (such as the transceiver unit 21 and the ECU 100). The storage device 222 includes a main storage device such as a read-only memory (ROM) or a random access memory (RAM), and an auxiliary storage device such as a hard disk drive (HDD) or a solid state drive (SSD). The processor 223 is an integrated circuit that executes various processes to realize the functions of the control unit 220, and may be configured using, for example, a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or the like that operates according to a program. The processor 223 executes various arithmetic and control processes by reading and executing programs stored in the storage device 222.

[0020] The ECU 100 is a unit that executes various processes for controlling the vehicle 1 based on information acquired from the object detection device 200 and the like. The ECU 100 includes an input / output device 110, a storage device 120, and a processor 130. The input / output device 110 is an interface device that enables transmission and reception of information between the ECU 100 and external mechanisms (such as the object detection device 200, drive mechanism, braking mechanism, steering mechanism, transmission mechanism, in-vehicle display, speakers, and various sensors). The storage device 120 includes a main storage device such as a ROM or RAM, and an auxiliary storage device such as an HDD or SSD. The processor 130 is an integrated circuit that executes various processes for realizing the functions of the ECU 100, and may be configured using, for example, a CPU, an ASIC, an FPGA, or the like. The processor 130 reads programs stored in the storage device 120 and executes various arithmetic and control processes.

[0021] (Distance calculation method using TOF method) Fig. 3 is a diagram showing an example of a distance calculation method using the TOF method. Fig. 3 illustrates an envelope L11 (echo information) that indicates a change over time in the intensity (signal level) of the ultrasonic waves transmitted and received by the transmitting and receiving unit 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 ultrasonic waves transmitted and received by the transmitting and receiving unit 21 (the magnitude of vibration of the transducer 211).

[0022] Envelope L11 shows the change over time in intensity, which indicates the magnitude of vibration of oscillator 211. From envelope L11 shown in Fig. 3, it can be seen that oscillator 211 is driven to vibrate for time Ta from time t0, completing transmission of the transmission wave at time t1, and then the vibration of oscillator 211 due to inertia continues while attenuating for time Tb until time t2. Therefore, in the graph shown in Fig. 3, time Tb corresponds to the so-called reverberation time.

[0023] The envelope L11 reaches a peak at time t4, which is a time Tp after time t0 when the transmission of the transmission wave starts, at which time the magnitude of the vibration of the vibrator 211 reaches or exceeds the detection threshold Ith. This detection threshold Ith is a value set to distinguish whether the vibration of the vibrator 211 is caused by the reception of a reflected wave from an obstacle O (another vehicle, a structure, a pedestrian, etc.) or by the reception of a reflected wave from an object other than the obstacle O (for example, the road surface, etc.). Note that although the detection threshold Ith is shown as a constant value here, the detection threshold Ith may also be a variable value that changes depending on the situation. Vibrations having a peak equal to or greater than the detection threshold Ith can be considered to be caused by the reception of a reflected wave from the obstacle O.

[0024] The envelope L11 in this example shows that the vibration of the vibrator 211 attenuates after timing t4. Therefore, timing t4 corresponds to the timing at which reception of the reflected wave from the obstacle O is completed, in other words, the timing at which the transmission wave last transmitted at timing t1 returns as a reflected wave.

[0025] 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 obstacle 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.

[0026] 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 obstacle O, it is necessary to find the time Tf between the time t0 when the transmission of the transmitted wave begins 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 as 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.

[0027] The time t0 when the transmission wave starts to be transmitted can be easily identified as the time when the object detection device 200 starts to operate, and the time Ta as the transmission time of the transmission wave is determined in advance by settings, etc. Therefore, by identifying the time t4 when the intensity of the reflected wave reaches a peak equal to or exceeds the detection threshold Ith, the distance from the vehicle 1 (the transmitter / receiver 21, which is the source of the ultrasonic wave transmission and reception) to the obstacle O can be calculated.

[0028] The above calculation method is merely an example, and the distance from the vehicle 1 to the obstacle O may be calculated using any known or new method as appropriate.

[0029] (Functional configuration of object detection device 200) 4 is a diagram showing an example of the functional configuration of the object detection device 200 according to the embodiment. The object detection device 200 according to the present embodiment includes a request control unit 302 and a distance calculation unit 301.

[0030] The request control unit 302 controls the issuance of data acquisition requests, thereby controlling each of the transceiver units 21. A data acquisition request is a request to acquire a TOF for each of the transceiver units 21. As shown in FIG. 4, the request control unit 302 includes a first calculation unit 3021, a second calculation unit 3022, and a request issuing unit 3023. Here, the request control unit 302 and the distance calculation unit 301 are included in the control unit 220 described above.

[0031] These functional units (first calculation unit 3021, second calculation unit 3022, request issuing unit 3023, and distance calculation unit 301) can be realized, for example, by cooperation between hardware and software (programs, etc.) of object detection device 200 as shown in Fig. 2. Furthermore, at least some of these functional units may be realized by dedicated hardware (circuits).

[0032] The first calculation unit 3021 calculates the data acquisition request interval based on the number of operating transceivers and the upper limit TOF number. The number of active transceivers is the number of active transceivers. The upper limit of TOF number is the maximum number of TOFs that can be acquired in one data acquisition request, and is determined in advance.

[0033] The first calculation unit 3021 calculates the response time based on the number of active transceivers and the upper limit TOF number, and calculates the data acquisition request interval based on the calculated response time. The response time is the time it takes for the transmitter / receiver 21 to receive all reflected waves in response to one transmission of a transmitted wave.

[0034] More specifically, the first calculation unit 3021 calculates the response time using the following equation (1): Then, the first calculation unit 3021 adds a predetermined time to the response time to calculate the data acquisition request interval. Response time = Number of active transmitters and receivers x Maximum number of TOFs x (Transmission time per TOF) ···(1)

[0035] Here, the transmission time per TOF is the time required for returning information for one TOF from the transmitting / receiving unit 21 to the request control unit 302, and is expressed as the number of bits x bit rate.

[0036] Based on the data acquisition request interval calculated by the first calculation unit 3021, the second calculation unit 3022 calculates the request timing, which is the timing of the data acquisition request for each of the multiple transmission / reception units 21, and the number of requests, which is the number of times the data acquisition request is issued to each of the multiple transmission / reception units 21, so that the final data acquisition request can be issued just before the end of the minimum operating time of the transmission / reception unit 21.

[0037] The minimum operation time is the minimum necessary operation time that is predetermined based on the maximum distance that is desired to be detected by the transceiver unit 21. Specifically, the minimum operation time is the time obtained by dividing twice the maximum distance by the speed of sound. For example, if the maximum distance that is desired to be detected by the transceiver unit 21 is 6 m from the transceiver unit 21, the time obtained by dividing the round-trip distance of 12 m by the speed of sound is the minimum operation time of the transceiver unit 21.

[0038] More specifically, the second calculation unit 3022 calculates the number of requests by dividing the minimum operation time by the data acquisition request interval. The second calculation unit 3022 also calculates the request timing by counting back the data acquisition request interval by the number of requests from the time immediately before the end of the minimum operation time.

[0039] The request issuing unit issues a data acquisition request to each of the multiple transmitting / receiving units 21 at the request timing and number of requests calculated by the second calculation unit 3022.

[0040] Fig. 5 is a diagram showing an example of the timing of a data acquisition request and the calculation of the number of requests in an embodiment. The upper time chart in Fig. 5 shows the timing of issuing a data acquisition request from the control unit 220 (request control unit 302) to the transceiver unit 21. The lower time chart in Fig. 5 shows the timing of transmitting a TOF from the transceiver unit 21 to the control unit 220 (distance calculation unit 301).

[0041] In the example of FIG. 5, the first calculation unit 3021 adds a predetermined margin (short time) to the response time shown in the lower time chart to calculate the data acquisition request interval shown in the upper time chart.

[0042] 5, the second calculation unit 3022 divides the minimum operation time of the transmitter / receiver 21 by the data acquisition request interval to obtain 8, and sets this 8 as the number of requests. Also, in the example of Fig. 5, the second calculation unit 3022 determines that the request timing for the data acquisition request is the point in time that goes back eight data acquisition request intervals from just before the end of the minimum operation time of the transmitter / receiver 21. The second calculation unit 3022 then determines that the request timing for the first data acquisition request is the point in time that goes back eight data acquisition request intervals from just before the end of the minimum operation time of the transmitter / receiver 21.

[0043] Returning to FIG. 4, the distance calculation unit 301 calculates the obstacle distance, which is the distance from the vehicle 1 to the obstacle O, based on the timing of transmission and reception of ultrasonic waves by each transmission and reception unit 21.

[0044] The reflected waves received by each transceiver 21 according to this embodiment include direct waves and indirect waves. A direct wave is a reflected wave corresponding to a transmission wave transmitted from a certain transceiver 21 (e.g., transceiver 21A), and is received by the same transceiver 21 (e.g., transceiver 21A) as the transceiver 21 that transmitted the transmission wave. An indirect wave is a reflected wave corresponding to a transmission wave transmitted from a certain transceiver 21 (e.g., transceiver 21A), and is received by a transceiver 21 (e.g., transceiver 21B) different from the transceiver 21 that transmitted the transmission wave.

[0045] The distance calculation unit 301 of this embodiment calculates the obstacle distance using the well-known trilateration (also called triangulation) method, utilizing the reception timing of the direct wave, the reception timing of the indirect wave, or the reception timing of both the direct wave and the indirect wave.

[0046] (Data acquisition request control process) Next, a control process for a data acquisition request performed by the object detection device 200 of this embodiment configured as described above will be described. FIG. 6 is a flowchart illustrating an example of a procedure for a data acquisition request control process according to the embodiment.

[0047] First, the first calculation unit 3021 calculates the response time from the number of operating transceivers 21, that is, the number of operating transceivers, and the upper limit TOF number, using the above-mentioned formula (1) (S101). Next, the first calculation unit 3021 adds a predetermined time (margin) to the response time calculated in S101 to calculate the data acquisition request interval (S102).

[0048] Next, the second calculation unit 3022 calculates the request timing and the number of requests for the data acquisition request, which allows the final data acquisition request to be issued just before the end of the minimum operation time of the transmission / reception unit 21, based on the minimum operation time of the transmission / reception unit 21 and the data acquisition request interval (S103).

[0049] Next, the request issuing unit 2023 reflects the request timing and the number of requests calculated in S103 in the communication of each transmitting / receiving unit 21 (S104). That is, the request issuing unit 2023 issues a data acquisition request to each transmitting / receiving unit 21 at the request timing and the number of requests calculated in S103.

[0050] (Overview) Usually, there are multiple timings for issuing data acquisition requests during one minimum operation time of the transmitter / receiver 22.

[0051] 7A and 7B are schematic diagrams illustrating an example of a comparison between the timing of a data acquisition request according to the embodiment and the timing of a data acquisition request according to the prior art, where Fig. 7A illustrates an example of the timing of a data acquisition request according to the prior art, and Fig. 7B illustrates an example of the timing of a data acquisition request according to the present embodiment.

[0052] In the prior art, as shown in FIG. 7(a), depending on the vehicle conditions, if the final data acquisition request is set after the minimum operation time has elapsed, a waiting time occurs, which may make it difficult to operate the transmitter / receiver unit 21 efficiently.

[0053] Therefore, the object detection device 200 of this embodiment comprises a plurality of transceiver units 21, each of which transmits a transmission wave and receives a reflected wave generated when the transmission wave is reflected by an object, and a request control unit 302 that controls the plurality of transceiver units 21. The request control unit 302 comprises a first calculation unit 3021 that calculates a data acquisition request interval, which indicates the time interval between data acquisition requests, based on the number of operating transceivers, which indicates the number of operating transceivers 21, and an upper limit TOF number, which indicates the upper limit of the number of TOFs that can be acquired in one data acquisition request that requests each of the plurality of transceivers 21 to acquire a TOF; a second calculation unit 3022 that calculates, based on the data acquisition request interval, a request timing, which is the timing of the data acquisition request, and a request count, which is the number of times a data acquisition request is issued to each of the plurality of transceivers 21, so that the final data acquisition request can be issued just before the end of the minimum operating time of the transceiver unit 21 based on the maximum distance to be detected; and a request issuance unit 3023 that issues a data acquisition request to each of the plurality of transceivers 21 based on the request timing and the request count.

[0054] 7(b), the request timing and the number of requests for the data acquisition request are calculated so that the final data acquisition request can be issued just before the end of the minimum operation time of the transceiver unit 21. Then, in the present embodiment, a data acquisition request is issued to the transceiver unit 21 at the calculated data acquisition request timing and number of requests, dynamically switching the operation of the transceiver unit 21. Therefore, according to the present embodiment, it is possible to realize efficient operation by the transceiver unit 21 according to the vehicle situation, and thereby to realize detection by the transceiver unit at an optimal detection cycle according to the vehicle situation.

[0055] Furthermore, in the object detection device 200 according to this embodiment, the first calculation unit 3021 calculates a response time, which is the time it takes to receive all reflected waves from a single transmission of a transmitted wave by the transceiver unit 21, based on the number of operating transceivers and the upper limit TOF number, and calculates a data acquisition request interval based on the calculated response time.

[0056] Therefore, according to this embodiment, the response time is calculated first, and then the data acquisition request interval is calculated, so that the data acquisition request interval can be determined more accurately. Therefore, according to this embodiment, detection can be performed by the transmitting and receiving unit at a more optimal detection period depending on the vehicle situation.

[0057] Furthermore, in the object detection device 200 according to this embodiment, the first calculation unit 3021 calculates the response time using the formula: response time = number of operating transceivers x maximum number of TOFs x (transmission time per TOF), and calculates the data acquisition request interval by adding a predetermined time to the response time.

[0058] Therefore, according to this embodiment, the response time is calculated using the number of operating transceivers, the upper limit number of TOFs, and the transmission time per TOF, and a predetermined time margin is added to this response time to calculate the data acquisition request interval. Therefore, according to this embodiment, the response time and the data acquisition request interval can be determined more accurately, and detection can be achieved by the transceivers at a more optimal detection cycle depending on the vehicle situation.

[0059] Furthermore, in the object detection device 200 according to this embodiment, the second calculation unit 3022 calculates the number of requests by dividing the minimum operation time by the data acquisition request interval, and calculates the request timing by counting back the data acquisition request interval by the number of requests from the time immediately before the end of the minimum operation time.

[0060] Therefore, according to this embodiment, the timing and number of requests for data acquisition can be determined more accurately, thereby enabling the transmitter / receiver unit to perform detection at a more optimal detection period depending on the vehicle conditions.

[0061] A program that causes a computer (e.g., processor 223, etc.) to execute processing for realizing the functions of object detection device 200 can be provided by being recorded 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 by being pre-installed in a ROM or the like. Furthermore, the program may be provided or distributed via a network such as the Internet.

[0062] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0063] 1...vehicle, 2...vehicle body, 21, 21A to 21L...transmitter / receiver unit, 50...vehicle control system, 100...ECU, 200...object detection device, 211...vibrator, 220...control unit, 221...input / output device, 222...storage device, 223...processor, 301...distance calculation unit, 302...request control unit, 3021...first calculation unit, 3022...second calculation unit, 3023...request issuing unit, O...obstacle (object).

Claims

1. An object detection device mounted on a moving body and detecting an object present around the moving body, a plurality of transceivers, each of which transmits a transmission wave and receives a reflected wave generated when the transmission wave is reflected by an object; a control unit that controls the plurality of transmission / reception units, The control unit a first calculation unit that calculates a data acquisition request interval that indicates a time interval between the data acquisition requests based on an operating transceiver count that indicates the number of operating transceivers and an upper limit TOF number that indicates an upper limit of the number of TOFs (Time of Flight) that can be acquired in one data acquisition request that requests acquisition of TOFs from each of the plurality of transceivers; a second calculation unit that calculates a request timing, which is the timing of the data acquisition request, for each of the plurality of transceivers, and a request count, which is the number of times the data acquisition request is issued to each of the plurality of transceivers, based on the data acquisition request interval, so that the final data acquisition request can be issued just before the end of a minimum operation time of the transceivers based on a maximum distance to be detected; an issuing unit that issues the data acquisition request to each of the plurality of transmitting / receiving units based on the request timing and the number of requests; An object detection device comprising:

2. the first calculation unit calculates a response time, which is a time required for receiving all of the reflected waves in response to one transmission of the transmission waves by the transceiver unit, based on the number of operating transceivers and the upper limit TOF number, and calculates the data acquisition request interval based on the calculated response time. The object detection device according to claim 1 .

3. The first calculation unit calculates the response time by the following formula: The response time = the number of operating transceivers × the upper limit number of TOFs × (transmission time per TOF) adding a predetermined time to the response time to calculate the data acquisition request interval; The object detection device according to claim 2 .

4. the second calculation unit calculates the number of requests by dividing the minimum operation time by the data acquisition request interval, and calculates the request timing by counting back the data acquisition request interval by the number of requests from the time immediately before the end of the minimum operation time. The object detection device according to claim 1 .

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