Object detection device

Abstract

An object detection device is provided. This object detection device is provided with: a control unit that controls a transmission / reception unit so that the transmission / reception unit transmits a transmission wave at a predetermined transmission time point; a distance calculation unit that calculates the distance between the vehicle and the object on the basis of the transmitted wave and the received wave; and a determination unit that determines a random time on the basis of a normal state in which the distance between the vehicle and the object is greater than a first distance or no object is detected, a first proximity state in which the distance between the vehicle and the object is equal to or less than the first distance, and a second proximity state in which the distance between the vehicle and the object is equal to or less than a second distance smaller than the first distance. The control unit controls the transmission / reception unit so as to transmit the transmission wave at a new transmission time point obtained by delaying the transmission time point by the determined random time.

Description

Technical Field

[0001] Embodiments of the present invention relate to an object detection device. Background Art

[0002] In a vehicle control system or the like, an object detection device is used. The object detection device transmits a transmission wave such as ultrasound from a vehicle and receives a reception wave (reflected wave) generated by the transmission wave being reflected by an object, thereby detecting an object existing around the vehicle.

[0003] In such an object detection device, when the time point of transmitting ultrasonic waves is constant between the own vehicle and other vehicles, interference may occur, such as mistaking the ultrasonic waves transmitted by other vehicles for those transmitted by the own vehicle. In the prior art, such interference is avoided by changing the time point of transmitting ultrasonic waves by the own vehicle.

[0004] Patent Document 1: Japanese Patent No. 6413620

[0005] Patent Document 2: Japanese Patent Application Publication No. 2018-59826

[0006] However, when the vehicle is interfered with, the other vehicles are also interfered with by the ultrasonic wave from the vehicle. Therefore, in such prior art, when the vehicle and other vehicles are equipped with the same object detection device with the same interference avoidance method, when both the vehicle and other vehicles take actions to avoid interference, as a result, the timing of sending ultrasonic waves may be aligned, and interference cannot be avoided. Summary of the invention

[0007] The object detection device of the embodiment is an object detection device that is mounted on a vehicle and detects an object existing around the above-mentioned vehicle, and includes: a control unit, which controls the transceiver unit that transmits a transmission wave and receives a reception wave generated by the reflection of the above-mentioned transmission wave by the above-mentioned object to make the transceiver unit send the above-mentioned transmission wave at a predetermined transmission time point; a distance calculation unit, which calculates the distance between the above-mentioned vehicle and the above-mentioned object based on the above-mentioned transmission wave and the reception wave; and a determination unit, which determines the waiting time, that is, the random time, for staggering the above-mentioned transmission time point according to a normal state in which the distance between the above-mentioned vehicle and the above-mentioned object is greater than a first distance or the above-mentioned object is not detected, a first proximity state in which the distance between the above-mentioned vehicle and the above-mentioned object is less than the first distance, and a second proximity state in which the distance between the above-mentioned vehicle and the above-mentioned object is less than a second distance smaller than the above-mentioned first distance, respectively, and the above-mentioned control unit controls the above-mentioned transceiver unit to send the above-mentioned transmission wave at a new transmission time point obtained by delaying the above-mentioned transmission time point by the determined above-mentioned random time.

[0008] According to the embodiment of the present invention, as an example, even when another vehicle is equipped with the same type of object detection device as that of the own vehicle, interference by ultrasonic waves can be reliably avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a plan view showing an example of the structure of the vehicle according to the embodiment.

[0010] Figure 2 This is a block diagram showing an example of the hardware configuration of the vehicle control system according to the embodiment.

[0011] Figure 3 This is a block diagram showing an example of the functional configuration of the object detection device according to the present embodiment.

[0012] Figure 4 This is a diagram showing an example of the transition of the vehicle state according to the present embodiment.

[0013] Figure 5A This is a diagram showing an example of a random table when the vehicle state is a normal state in the present embodiment.

[0014] Figure 5B 1 is a diagram showing an example of a random table when the vehicle state is the first approaching state in the present embodiment.

[0015] Figure 5C 2 is a diagram showing an example of a random table when the vehicle state is the second approach state in the present embodiment.

[0016] Figure 6 This is a flowchart showing an example of a procedure of ultrasonic transmission processing according to the present embodiment.

[0017] Figure 7 This is a diagram showing an example of the timing of transmitting ultrasonic waves at random times in a conventional object detection device.

[0018] Figure 8 This is a diagram showing an example of the timing of transmitting ultrasonic waves at random times in a conventional object detection device. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The structures of the embodiments described below and the operations and effects brought about by the structures are merely examples, and the present invention is not limited to the following descriptions.

[0020] Figure 11 is a top view showing an example of the structure of a vehicle 1 according to the embodiment. The vehicle 1 is an example of a mobile body equipped with the object detection device according to the embodiment. The object detection device according to the embodiment is a device that detects objects existing around the vehicle 1 based on information such as TOF (Time Of Flight) and Doppler shift obtained by transmitting a transmission wave from the vehicle 1 and receiving a reception wave (reflected wave) generated by the transmission wave being reflected by the object.

[0021] The object detection device according to the present embodiment is connected to a plurality of transceivers 21A to 21L. Here, when it is not necessary to distinguish between the plurality of transceivers 21A to 21L, they are hereinafter referred to as the transceiver 21 .

[0022] Each transceiver 21 is provided on the vehicle body 2 as the exterior of the vehicle 1, transmits ultrasonic waves (an example of transmission waves) toward the outside of the vehicle body 2, and receives reflected waves from objects existing outside the vehicle body 2 as reception waves. Figure 1 In the example shown, 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 at the right side surface, and two transceivers 21K and 21L are arranged at the left side surface. The number and installation positions of the transceivers 21 are not limited to this example.

[0023] Figure 2 1 is a block diagram showing an example of a hardware structure 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 transceiver 21. The vehicle control system 50 according to this embodiment mainly includes an ECU (Electronic Control Unit) 100, a plurality of transceivers 21, a brake system 221, a buzzer 222, and an engine 223.

[0024] The ECU 100 and each transceiver 21 are connected via a LIN (Local Interconnect Network) 240 as an in-vehicle network. In addition, the ECU 100 and the brake system 221, buzzer 222, engine 223, and shift sensor 224 are connected via a CAN (Controller Area Network) 230 as an in-vehicle network.

[0025] Each transceiver 21 includes a vibrator 211 formed by a piezoelectric element, an amplifier, etc., and realizes the transmission and reception of ultrasonic waves through the vibration of the vibrator 211. Specifically, each transceiver 21 transmits the ultrasonic wave generated by the vibration of the vibrator 211 as a transmission wave, and detects the vibration of the vibrator 211 formed by the reflected wave (received wave) obtained by the reflection of the transmission wave by objects such as obstacles O and road surface RS. The vibration of the vibrator 211 is converted into an electrical signal, and based on the electrical signal, the TOF corresponding to the distance from the transceiver 21 to the obstacle O, the Doppler shift information corresponding to the relative speed of the obstacle O, etc. can be obtained.

[0026] In addition, Figure 2 In the example shown, a configuration is shown in which both transmission of the transmission wave and reception of the reception wave are performed using a single transducer 211, but the configuration of the transceiver 21 is not limited thereto. For example, a configuration in which the transmission side and the reception side are separated may be used, such as a configuration in which a transducer for transmitting the transmission wave and a transducer for receiving the reception wave are separately provided.

[0027] ECU 100 is a unit that executes various processes for controlling vehicle 1 based on various information. ECU 100 can control brake system 221, engine 223, etc. or output sound to buzzer 222 by sending control signals via CAN 230. ECU 100 can also receive detection results from various sensors (not shown) via CAN 230.

[0028] like Figure 2 As shown, ECU 100 includes CPU (Central Processing Unit) 130, SSD 121 (Solid State Drive), ROM (Read Only Memory) 122, and RAM (Random Access Memory) 123. ECU 100 is an example of an object detection device. ECU 100 is sometimes referred to as object detection device 100.

[0029] In addition to being able to perform output processing such as outputting an alarm to the buzzer 222, detecting an object, and determining whether there is interference with an object, the CPU 130 can also perform various calculation processing and control. The ROM 122 is a non-volatile storage device. The ROM 122 stores a program in advance. The CPU 130 can read the program stored in the ROM 122 and perform calculation processing according to the program.

[0030] RAM123 temporarily stores various data used in the calculation of CPU130. In addition, SSD121 is a rewritable non-volatile storage unit that can store data even when the power of ECU100 is disconnected. In addition, CPU130, ROM122, RAM123, etc. can be integrated in the same package. In addition, ECU100 can also be a structure that uses other logic operation processors such as DSP (Digital Signal Processor), logic circuits, etc. instead of CPU130. In addition, HDD (Hard Disk Drive) can be set instead of SSD121, and SSD121 and HDD can also be set separately from ECU100.

[0031] The brake system 221 is, for example, an ABS (Anti-lock Brake System) that suppresses brake locking, an anti-skid device (ESC: Electronic Stability Control) that suppresses the vehicle 1 from skidding when turning, an electric brake system that increases the braking force (performs brake assist), BBW (Brake By Wire), etc.

[0032] The engine 223 is a prime mover for driving the vehicle 1 .

[0033] The buzzer 222 is provided inside the vehicle 1 and outputs an alarm.

[0034] Next, the functional structure of the object detection device (ECU) 100 will be described.

[0035] Figure 3 1 is a block diagram showing an example of the functional structure of the object detection device 100 according to the present embodiment. Figure 3 As shown, the object detection device 100 according to the present embodiment mainly includes a sound wave control unit 150 , a vehicle state estimation unit 160 , a notification control unit 162 , a vehicle information management unit 163 , and a brake control unit 164 .

[0036] The vehicle state estimation unit 160 estimates various states of the vehicle 1. In the present embodiment, the state of the vehicle 1 is estimated as any one of a normal state, a first approach state, and a second approach state based on the distance between the vehicle 1 and the object calculated by the detection distance calculation unit 1521 described below. Here, the details of the normal state, the first approach state, and the second approach state will be described below.

[0037] When the vehicle 1 approaches an object, that is, when the abnormality detection unit 1522 described below determines that the distance between the vehicle 1 and the object calculated by the detection distance calculation unit 1521 described below based on the ultrasonic waves transmitted and received by the transceiver 21 is less than a predetermined distance, the notification control unit 162 reports by outputting an alarm from the buzzer 222. The vehicle information management unit 163 manages various information of the vehicle 1. The brake control unit 164 controls the brakes made by the brake system 221.

[0038] The sound wave control unit 150 controls the transmission of ultrasonic waves by the transceiver unit 21, or manages information obtained based on the reflected waves received by the transceiver unit 21. Figure 3 As shown, the sound wave control unit 150 includes a transmission and reception control unit 1510 and a transmission and reception information management unit 1520 .

[0039] The transceiver control unit 1510 controls the transceiver unit 21 to transmit and receive ultrasonic waves. Figure 3 As shown, the transmission and reception control unit 1510 includes a transmission control unit 1511 , a random time determination unit 1512 , and a random table 1513 .

[0040] The wave transmission control unit 1511 controls the transceiver unit to transmit the ultrasonic wave at a predetermined transmission time point. More specifically, the wave transmission control unit 1511 controls the transceiver unit 21 to transmit the ultrasonic wave at a new transmission time point obtained by delaying the transmission time point by a random time determined by a random time determination unit 1512 described below. Here, the random time is a waiting time for staggering the transmission time point of the ultrasonic wave. The wave transmission control unit 1511 is an example of a control unit.

[0041] The random time determination unit 1512 determines the random time according to the normal state, the first approach state, and the second approach state, which are states of the vehicle 1. The random time determination unit 1512 is an example of a determination unit.

[0042] In addition, the normal state is a state in which the distance between the vehicle and the object is greater than the first distance or the object is not detected. The first approach state is a state in which the distance between the vehicle and the object is less than the first distance. The second approach state is a state in which the distance between the vehicle and the object is less than the second distance smaller than the first distance. In the present embodiment, based on the distance between the vehicle and the object calculated by the detection distance calculation unit 1521, the vehicle state is classified into three states, and the vehicle state transitions between the three states. In the present embodiment, the first distance is set to 3m and the second distance is set to 1m, but it is not limited thereto.

[0043] Figure 4 This is a transition diagram of the vehicle state in this embodiment.

[0044] When the vehicle state is in a normal state, the vehicle state changes to the first proximity state when the detected distance between the vehicle and the object is the first distance, i.e., less than 3m, and is continuously the same distance (within 15cm after the corrected moving distance), and the two closest times did not change to the first proximity state.

[0045] When the vehicle state is in the normal state, if the detected distance between the vehicle and the object is less than 1 m which is the second distance, the vehicle state transitions to the second approaching state when the distance becomes less than 1 m for the first time.

[0046] In cases other than these, the vehicle state does not change from the normal state.

[0047] Furthermore, after the vehicle state changes to the first approach state, it does not change to the second approach state but changes to the normal state. After the vehicle state changes to the second approach state, it does not change to the first approach state but changes to the normal state.

[0048] That is, the random time determination unit 1512 determines the random time in the first proximity state or the random time in the second proximity state, and after the transmission control unit 1511 transmits the transmission wave at the new transmission time point, determines the random time in the normal state.

[0049] Specifically, the random time determination unit 1512 refers to the random table 1513 and determines the random time of the ultrasonic wave emitted as the transmission wave from the transceiver units 21A~21D arranged at the front of the vehicle 1 and the random time of the ultrasonic wave emitted from the transceiver units 21E~21H arranged at the rear of the vehicle 1 to different times according to the state of the vehicle 1.

[0050] The random table 1513 is stored in a storage medium such as SSD 121. The random table 1513 determines the random time (an example of the first random time) of the transmission wave emitted from the transceiver 21A to 21D disposed at the front of the vehicle 1 and the random time (an example of the second random time) of the transmission wave emitted from the transceiver 21E to 21H disposed at the rear of the vehicle 1 according to each vehicle state, that is, according to the normal state, the first approach state, and the second approach state.

[0051] Figure 5A to Figure 5C This is a diagram showing an example of a random table according to the present embodiment. Figure 5A This is a diagram showing an example of a random table in a normal state. Figure 5B : is a diagram showing an example of a random table in the case of the first approach state. Figure 5C : is a diagram showing an example of a random table in the case of the second approach state.

[0052] exist Figure 5A to Figure 5CIn the random time of Fr (front), the random time (first random time) of the transmission wave (that is, ultrasonic wave) emitted from the transceiver 21A to 21D provided at the front of the vehicle 1, and the random time of Rr (rear) is the random time (second random time) of the transmission wave (that is, ultrasonic wave) emitted from the transceiver 21E to 21H provided at the rear of the vehicle 1. In addition, three random times are set for the random time of Fr (front) and the random time of Rr (rear), respectively, but an arbitrary random time is determined from them.

[0053] Here, the first distance is smaller than the distance obtained based on the difference between the random time corresponding to the first approach state and the random time corresponding to the normal state. In addition, the second distance is smaller than the distance obtained based on the difference between the random time corresponding to the second approach state and the random time corresponding to the normal state.

[0054] That is, if the sound wave transmission time point is offset by 1 ms, the estimated error of the distance becomes about 175 mm. In addition, the estimated error varies with temperature. When the vehicle state changes from the normal state to the first approach state or the second approach state and the random table 1513 is changed, the random time determination unit 1512 selects the minimum value of the random table in such a way that the random time and the detection distances that become the transition conditions, i.e., the first distance and the second distance, satisfy the conditions of the following formulas (1) and (2).

[0055] When changing from the normal state to the first approach state

[0056] 175×(minimum value of random time in the first approach state - maximum value of random time in the normal state) > first distance...(1)

[0057] When changing from the normal state to the second approach state

[0058] 175×(minimum value of random time in the second approach state - maximum value of random time in the normal state)>second distance...(2)

[0059] That is, in this embodiment, the first distance is 3m, so Figure 5A , Figure 5B In the random table 1513 of the formula, the random time is set to satisfy the above formula (1). In addition, in this embodiment, the second distance is 3m, so Figure 5A , Figure 5C In the random table 1513 of the formula, the random time is set to satisfy the above formula (2).

[0060] Moreover, as described above, after the vehicle state is changed to the first approach state, it is not changed to the second approach state, but is changed to the normal state. After the vehicle state is changed to the second approach state, it is not changed to the first approach state, but is changed to the normal state. That is, the random time determination unit 1512 determines the random time according to the random table of the normal state. Therefore, if the normal state is changed after the vehicle state is changed to the first approach state, the distance obtained by multiplying the difference between the random time of the first approach state and the random time of the normal state by 175m is greater than the first distance, and no ultrasonic wave is sent corresponding to the distance, so that interference between the ultrasonic waves of the vehicle and other vehicles can be avoided.

[0061] Similarly, if the vehicle changes to the normal state after changing to the second proximity state, the distance obtained by multiplying the difference between the random time of the second proximity state and the random time of the normal state by 175m is greater than the second distance, and no ultrasonic wave is sent corresponding to this distance. Therefore, interference between the ultrasonic waves of this vehicle and other vehicles can be avoided.

[0062] The transmission and reception information management unit 1520 manages information based on the reflected waves received by the transmission and reception unit 21. Figure 3 As shown, the transmission and reception information management unit 1520 includes a detection distance calculation unit 1521 and an abnormality detection unit 1522 .

[0063] The detection distance calculation unit 1521 calculates the distance from the vehicle to the object based on the transmission wave sent by the transceiver unit 21 and the received reflected wave. Specifically, the detection distance calculation unit 1521 detects the object based on information such as TOF and Doppler shift obtained by receiving the received wave (reflected wave) generated by the reflection of the transmission wave by the object, and calculates the distance between the vehicle and the object. Here, the distance calculation method uses a well-known method.

[0064] The abnormality detection unit 1522 detects abnormalities of the vehicle 1, etc. In the present embodiment, when the distance calculated by the detection distance calculation unit 1521 is less than a predetermined distance, the abnormality detection unit 1522 determines that an object is approaching. In addition, the abnormality detection unit 1522 detects whether the ultrasonic wave has caused interference based on the distance calculated by the detection distance calculation unit 1521. For example, when the abnormality detection unit 1522 detects that the distance calculated by the detection distance calculation unit 1521 is less than a predetermined threshold value three times in a row, it determines that the ultrasonic wave has caused interference. In addition, the detection method of ultrasonic interference is not limited to this.

[0065] Next, the ultrasonic wave transmission process performed by the object detection device 100 according to the present embodiment having the above configuration will be described.

[0066] Figure 61 is a flowchart showing an example of a procedure of ultrasonic wave transmission processing according to the present embodiment. This transmission processing is performed when the vehicle 1 starts traveling.

[0067] First, the random time determination unit 1512 obtains the distance between the vehicle and the object calculated by the detection distance calculation unit 1521 (S11). Then, the random time determination unit 1512 determines whether the obtained current distance is less than the second distance (S12). Here, the number of times the distance is less than the second distance is set to 1. Then, when the distance is less than the second distance (S12: Yes), the vehicle state changes to the second approach state, and the random time determination unit 1512 changes from Figure 5C A random time is selected from the random table 1513 of the second approach state shown (S13).

[0068] In S12, if the distance is greater than the second distance (S12: No), the random time determination unit 1512 determines whether the current distance is less than the first distance and is the same distance twice in a row (S14). If the current distance is less than the first distance and is the same distance twice in a row (S14: Yes), the vehicle state changes to the first approach state, and the random time determination unit 1512 changes from Figure 5B A random time is selected from the random table 1513 of the first approach state shown (S15).

[0069] Then, the wave transmission control unit 1511 controls the transceiver 21 to transmit ultrasonic waves at a time point shifted from the random time determined in S13 and S15. As a result, the transceiver 21 transmits ultrasonic waves at a time point shifted from the random time (S17).

[0070] Next, the vehicle state changes to the normal state, and the random time determination unit 1512 changes from Figure 5A A random time is selected from the random table 1513 in the normal state shown (S18).

[0071] Then, the wave transmission control unit 1511 controls the transceiver 21 to transmit ultrasonic waves at a time point shifted from the random time determined in S18, whereby the transceiver 21 transmits ultrasonic waves at a time point shifted from the random time (S19).

[0072] Returning to S14, if the current distance is greater than the first distance or the current distance is less than the first distance but is not the same distance twice in a row (S14: No), the random time determination unit 1512 changes from Figure 5A A random time is selected from the random table in the normal state shown (S16).

[0073] Then, the wave transmission control unit 1511 controls the transceiver 21 to transmit ultrasonic waves at a time point shifted from the random time determined in S16, whereby the transceiver 21 transmits ultrasonic waves at a time point shifted from the random time (S19).

[0074] In the past, ultrasonic waves were sent from a vehicle to detect an object, and when the distance between the vehicle and the object was close to a predetermined distance, an alarm was output from a buzzer. Here, when the time point of sending ultrasonic waves is constant between the vehicle and the other vehicle, when the vehicle receives ultrasonic waves sent by other vehicles, the ultrasonic waves are sometimes mistakenly recognized as reflected waves of the ultrasonic waves sent by the vehicle, so-called interference. For example, if ultrasonic waves are sent simultaneously between the vehicle and the other vehicle, the ultrasonic waves returned from the vehicle at half the distance are mistakenly recognized as reflected waves. Therefore, if the object is at a close distance and is mistakenly recognized as within the range of the buzzer output, the buzzer is mistakenly output.

[0075] Therefore, as a method for avoiding erroneous recognition caused by such interference, there is a method as follows: in an existing object detection device, when the same distance is continuously detected at a predetermined threshold or above, it is determined that interference has occurred. For example, the object detection device determines that interference has occurred when the distance is 30 cm detected three times in a row. When it is determined that interference has occurred, the object detection device can avoid continuous detection of the same distance by staggering the transmission time of the ultrasonic wave.

[0076] Figure 7 , Figure 8 FIG. 1 is a diagram showing an example of the timing of transmitting ultrasonic waves at random intervals in a conventional object detection device. Figure 7 As shown, for example, ultrasonic waves are transmitted at intervals of 168 ms, but when it is determined that interference occurs, the object detection device transmits ultrasonic waves every 172 ms with a random time difference of 4 ms, thereby avoiding interference.

[0077] However, when the vehicle receives ultrasonic waves from other vehicles, other vehicles may also receive ultrasonic waves from the vehicle. In this case, it is possible to consider the case where vehicles are equipped with object detection devices that use the same method as the existing interference avoidance processing. In this case, the object detection device detects that it is interfered with, and even if the transmission time of the ultrasonic wave of the vehicle is shifted, if other vehicles also use the same method to shift the transmission time, such as Figure 8 As shown, this will again cause the transmission time points to coincide, which may cause interference.

[0078] In contrast, in the present embodiment, the random time determination unit 1512 determines the waiting time, i.e., the random time, for shifting the transmission time point according to the normal state in which the distance between the vehicle and the object is greater than the first distance or the object is not detected, the first approach state in which the distance between the vehicle and the object is less than the first distance, and the second approach state in which the distance between the vehicle and the object is less than the second distance less than the first distance, respectively, and the wave transmission control unit 1511 controls the transceiver unit 21 to transmit the transmission wave at a new transmission time point obtained by delaying the transmission time point by the determined random time. Therefore, according to the present embodiment, even if other vehicles are equipped with the same type of object detection device as the vehicle itself, the random time is delayed according to the state of the vehicle 1, so that the interference of ultrasonic waves can be effectively avoided.

[0079] In addition, in the present embodiment, the first distance is smaller than the distance calculated based on the difference between the random time corresponding to the first approach state and the random time corresponding to the normal state, and the second distance is smaller than the distance calculated based on the time difference between the random time corresponding to the second approach state and the above random time corresponding to the above normal state. The random time determination unit 1512 determines the random time corresponding to the normal state after the transmission wave is transmitted at a new transmission time point in the first approach state or the second approach state by the wave transmission control unit 1511. Therefore, by changing from the first approach state or the second approach state to the normal state, the distance corresponding to the difference in random time becomes larger than the first distance as the transition condition for changing from the normal state to the first approach state and the second distance as the transition condition for changing from the normal state to the second approach state. Therefore, according to the present embodiment, even if the other vehicle is equipped with the same type of object detection device as the vehicle, the possibility of interference between the vehicle and the other vehicle can be reduced according to the distance of the difference, and the interference can be avoided more reliably.

[0080] Furthermore, in the present embodiment, the random time determination unit 1512 determines the random time of the transmission waves emitted from the transceiver units 21A to 21D disposed at the front of the vehicle 1 to be different from the random time of the transmission waves emitted from the transceiver units 21E to 21H disposed at the rear of the vehicle 1. Therefore, according to the present embodiment, even if another vehicle is equipped with the same type of object detection device as the vehicle itself, interference by ultrasonic waves can be further reliably avoided according to the traveling direction of the vehicle 1.

[0081] In addition, in the present embodiment, the SSD 121 storing the random table 1513 is further provided, and the random table 1513 determines the random time corresponding to the normal state, the first approach state, and the second approach state, respectively, and the random time determination unit 1512 determines the random time based on the three states of the normal state, the first approach state, and the second approach state and the random table 1513. Therefore, according to the present embodiment, the random time can be determined by switching the random table, so that even if other vehicles are equipped with the same type of object detection device as the vehicle, the interference of ultrasonic waves can be easily and more reliably avoided.

[0082] In the above-mentioned embodiment, the CPU 130 reads and executes the program stored in the storage device such as the ROM 122 and the SSD 121, thereby realizing various functional modules such as the wave control unit 1511, the random time determination unit 1512, the detection distance calculation unit 1521, the abnormality detection unit 1522, the vehicle state estimation unit 160, the report control unit 162, the vehicle information management unit 163, and the brake control unit 164. However, it is not limited to this. For example, the various functional modules such as the wave control unit 1511, the random time determination unit 1512, the detection distance calculation unit 1521, the abnormality detection unit 1522, the vehicle state estimation unit 160, the report control unit 162, the vehicle information management unit 163, and the brake control unit 164 can also be realized by independent hardware.

[0083] In addition, the object detection program executed by object detection device 100 according to the above-described embodiment is provided by being installed in advance in a ROM or the like.

[0084] The object detection program executed in the object detection device 100 of the above-mentioned embodiment can also be configured as a file in an installable or executable form recorded on a recording medium that can be read by a computer, such as a CD-ROM, floppy disk (FD), CD-R, DVD (Digital Versatile Disk), etc.

[0085] Furthermore, the object detection program executed by the object detection device 100 of the above embodiment may be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. Furthermore, the object detection program executed by the object detection device 100 of the above embodiment may be provided or distributed via a network such as the Internet.

[0086] The object detection program executed by the object detection device 100 of the above-mentioned embodiment becomes a module structure including the above-mentioned parts (wave control unit 1511, random time determination unit 1512, detection distance calculation unit 1521, abnormality detection unit 1522, vehicle state estimation unit 160, report control unit 162, vehicle information management unit 163, brake control unit 164, etc.), and as actual hardware, the CPU reads out and executes the object detection program from the above-mentioned ROM, thereby, the above-mentioned parts are loaded on the main storage device, and the wave control unit 1511, random time determination unit 1512, detection distance calculation unit 1521, abnormality detection unit 1522, vehicle state estimation unit 160, report control unit 162, vehicle information management unit 163, brake control unit 164, etc. are generated on the main storage device.

[0087] Several embodiments of the present invention have been described, but these embodiments are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. These embodiments and their variations are included in the scope and purpose of the invention, and are included in the invention described in the claims and their equivalents.

[0088] [Summary of this embodiment]

[0089] The object detection device (100) of this embodiment has at least the following structure.

[0090] That is, the object detection device (100) is an object detection device (100) mounted on a vehicle (1) and detecting an object existing around the vehicle (1), and comprises: a control unit (1511) for controlling a transceiver (21) for transmitting a transmission wave and receiving a reception wave generated by the reflection of the transmission wave by the object to transmit the transmission wave at a predetermined transmission time point; a distance calculation unit (1521) for calculating the distance between the vehicle and the object based on the transmission wave and the reception wave; and a determination unit (1512) for determining the distance between the vehicle and the object according to the transmission wave and the reception wave. In a normal state in which the distance between the vehicle and the object is greater than the first distance or the object is not detected, in a first proximity state in which the distance between the vehicle and the object is less than the first distance, or in a second proximity state in which the distance between the vehicle and the object is less than a second distance smaller than the first distance, the control unit (1511) controls the transceiver unit (21) to send the transmission wave at a new sending time point obtained by delaying the sending time point by the determined random time.

[0091] According to this structure, as an example, even when another vehicle is equipped with the same type of object detection device (100) as the own vehicle, interference of ultrasonic waves can be reliably avoided.

[0092] In addition, in the object detection device (100) of the embodiment, the above-mentioned first distance is smaller than the distance calculated based on the difference between the above-mentioned random time corresponding to the above-mentioned first proximity state and the above-mentioned random time corresponding to the above-mentioned normal state, and the above-mentioned second distance is smaller than the distance calculated based on the time difference between the above-mentioned random time corresponding to the above-mentioned second proximity state and the above-mentioned random time corresponding to the above-mentioned normal state. After the above-mentioned determination unit (1512) sends a transmission wave at the above-mentioned new sending time point in the above-mentioned first proximity state or the above-mentioned second proximity state through the above-mentioned control unit (1511), the above-mentioned random time corresponding to the above-mentioned normal state is determined.

[0093] According to this configuration, as an example, even when another vehicle is equipped with the same type of object detection device (100) as the own vehicle, interference can be avoided more reliably.

[0094] In addition, in the object detection device (100) of the embodiment, the above-mentioned determination unit (1512) determines the random time of the above-mentioned transmission wave emitted from the above-mentioned transceiver unit (21) arranged at the front of the above-mentioned vehicle (1) and the random time of the above-mentioned transmission wave emitted from the above-mentioned transceiver unit (21) arranged at the rear of the above-mentioned vehicle (1) to be different times.

[0095] According to this structure, as an example, even when another vehicle is equipped with the same type of object detection device (100) as the own vehicle, interference of ultrasonic waves can be reliably avoided according to the traveling direction of the vehicle.

[0096] In addition, in the object detection device (100) of the embodiment, there is also a storage unit (121) for storing random information (1513), and the random information determines the random time corresponding to the normal state, the first proximity state and the second proximity state, respectively, and the determination unit (1512) determines the random time based on the three states of the normal state, the first proximity state and the second proximity state and the random information (1513).

[0097] According to this structure, as an example, even when another vehicle is equipped with the same type of object detection device (100) as the own vehicle, interference of ultrasonic waves can be easily and more reliably avoided.

[0098] Description of Reference Numerals

[0099] 1...Vehicle; 21...Transceiver; 50...Vehicle control system; 100...Object detection device (ECU); 121...SSD; 211...Vibrator; 150...Sound wave control unit; 1510...Transceiver control unit; 1511...Wave control unit; 1512...Random time determination unit; 1513...Random table; 1520...Transceiver information management unit; 1521...Detection distance calculation unit; 1522...Abnormality detection unit; 160...Vehicle state estimation unit; 162...Report control unit; 163...Vehicle information management unit; 164...Braking control unit.

Claims

1. An object detection device is mounted on a vehicle and detects an object existing around the vehicle, characterized in that: have: a control unit for controlling a transceiver unit that transmits a transmission wave and receives a reception wave generated by reflection of the transmission wave by the object, so that the transceiver unit transmits the transmission wave at a predetermined transmission time point; a distance calculation unit that calculates the distance between the vehicle and the object based on the transmitted wave and the received wave; as well as a decision unit for determining a waiting time, i.e., a random time, for shifting the transmission time point according to a normal state in which the distance between the vehicle and the object is greater than a first distance or the object is not detected, a first proximity state in which the distance between the vehicle and the object is less than the first distance, and a second proximity state in which the distance between the vehicle and the object is less than a second distance smaller than the first distance, respectively; The control unit controls the transceiver unit to transmit the transmission wave at a new transmission time point obtained by delaying the transmission time point by the determined random time.

2. The object detection device according to claim 1, characterized in that: The first distance is smaller than a distance calculated based on a difference between the random time corresponding to the first approach state and the random time corresponding to the normal state, and the second distance is smaller than a distance calculated based on a difference between the random time corresponding to the second approach state and the random time corresponding to the normal state. The determination unit determines the random time corresponding to the normal state after the control unit transmits the transmission wave at the new transmission time point in the first proximity state or the second proximity state.

3. The object detection device according to claim 2, characterized in that: The determination unit determines the random timing of the transmission wave emitted from the transmission and reception unit provided at the front of the vehicle and the random timing of the transmission wave emitted from the transmission and reception unit provided at the rear of the vehicle to be different times.

4. The object detection device according to claim 1, characterized in that: further comprising a storage unit for storing random information, wherein the random information determines random times corresponding to the normal state, the first approach state, and the second approach state, respectively; The determination unit determines the random time based on three states, namely, the normal state, the first proximity state, and the second proximity state, and the random information.

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