Object detection system, object detection method, and object detection device

Abstract

This invention discloses an object detection system, an object detection method, and an object detection apparatus. The object detection system includes multiple ranging sensors, a wave transmission control unit, and a determination unit. The multiple ranging sensors have a wave transmitting unit that transmits ultrasonic waves and a wave receiving unit that receives reflected waves of ultrasonic waves reflected by an object. The ranging sensors detect objects based on the reflected waves. The multiple ranging sensors are positioned at different locations within the vehicle. The wave transmission control unit sets the ranging sensors whose detection range includes the area of ​​an object previously detected when power supply to the vehicle begins, as the beginning of the wave transmission sequence, and repeatedly performs periodic wave transmission control, sequentially transmitting ultrasonic waves from each of the multiple ranging sensors according to this wave transmission sequence. The determination unit determines an object as a detected object when any of the multiple ranging sensors detects an object a predetermined number of times.

Description

Technical Field

[0001] This disclosure relates to an object detection system, an object detection method, and an object detection device. Background Technology

[0002] Previously, systems for detecting objects around a vehicle using sensors mounted on the vehicle were known. For example, a known device uses a radar device to scan the detection range at predetermined control cycles to suppress false detections, and identifies objects detected more than a predetermined number of times as objects to be contacted. Furthermore, techniques have been disclosed for reducing the number of detections when objects are detected using images from an infrared camera, thereby shortening the object detection time.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2012-247829 Summary of the Invention

[0006] However, in existing technologies, there are situations where high-precision object detection is difficult to achieve due to variations in the number of judgments. For example, in existing technologies, it is difficult to achieve both reduced detection time and high-precision object detection.

[0007] The non-limiting embodiments of this disclosure help to provide object detection systems, object detection methods, and object detection apparatuses that can achieve reduced detection time and high-precision object detection.

[0008] The object detection system disclosed herein includes multiple ranging sensors, a wave transmission control unit, and a determination unit. The multiple ranging sensors have a wave transmitting unit that transmits ultrasonic waves and a wave receiving unit that receives reflected waves of ultrasonic waves reflected by an object. The ranging sensors detect objects based on the reflected waves. The multiple ranging sensors are positioned at different locations within the vehicle. The wave transmission control unit sets the ranging sensor whose detection range includes an area containing an object previously detected when power supply to the vehicle begins as the beginning of the wave transmission sequence, and repeatedly performs periodic wave transmission control, sequentially transmitting ultrasonic waves from each of the multiple ranging sensors according to the wave transmission sequence. The determination unit determines an object as a detected object when any of the multiple ranging sensors detects an object a predetermined number of times.

[0009] Invention Effects

[0010] According to the object detection system, object detection method and object detection device disclosed herein, it is possible to achieve shortened detection time and high-precision object detection. Attached Figure Description

[0011] Figure 1 This is a schematic diagram illustrating an example of an object detection system according to an embodiment.

[0012] Figure 2 This is a schematic diagram illustrating an example of the structure of a ranging sensor according to an embodiment.

[0013] Figure 3 This is a block diagram illustrating an example of the functional structure of an object detection system according to an embodiment.

[0014] Figure 4 This is a hardware structure diagram illustrating an example of an object detection device according to an embodiment.

[0015] Figure 5A This is an explanatory diagram showing an example of conventional wave transmission control.

[0016] Figure 5B This is an explanatory diagram showing an example of conventional wave transmission control.

[0017] Figure 6A This is an explanatory diagram illustrating an example of wave transmission control in an embodiment.

[0018] Figure 6B This is an explanatory diagram illustrating an example of wave transmission control in an embodiment.

[0019] Figure 7 This is an explanatory diagram illustrating an example of wave transmission control in an embodiment.

[0020] Figure 8 This is an explanatory diagram illustrating an example of wave transmission control in an embodiment.

[0021] Figure 9 This is an explanatory diagram illustrating an example of wave transmission control in an embodiment.

[0022] Figure 10 This is an explanatory diagram illustrating an example of the transmission control in an implementation method.

[0023] Figure 11 This is an explanatory diagram illustrating an example of wave transmission control in an embodiment.

[0024] Figure 12 This is an explanatory diagram showing an example of multiple vehicles equipped with the object detection device of the embodiment.

[0025] Figure 13 This is a flowchart illustrating an example of the information processing flow of an implementation method. Detailed Implementation

[0026] The implementation of the object detection system and object detection method involved in this disclosure will be described below with reference to the accompanying drawings.

[0027] Figure 1 This is a schematic diagram illustrating an example of the object detection system 100 of this embodiment.

[0028] The object detection system 100 includes an object detection device 10 and multiple ranging sensors 20. The object detection device 10 is a device for detecting objects around the vehicle 1. In this embodiment, the object detection device 10 will be described as being mounted on the vehicle 1 as an example.

[0029] Multiple ranging sensors 20 are installed in vehicle 1.

[0030] The ranging sensor 20 is a sensor that detects objects around the vehicle 1. In this embodiment, the ranging sensor 20 has a detection distance of, for example, several centimeters to several meters, and detects whether there are objects at a relatively close distance and the distance to the objects. In this embodiment, the ranging sensor 20 is described as an ultrasonic sensor as an example. The ultrasonic sensor has a wave transmitting function, transmitting ultrasonic waves of 20kHz to 100kHz as transmitted waves; and a wave receiving function, receiving ultrasonic waves reflected by objects as reflected waves.

[0031] In this embodiment, the vehicle 1 includes distance sensors 20FL, 20FLC, 20FRC, 20FR, 20RL, 20RLC, 20RRC, and 20RR as distance sensors 20. These multiple distance sensors 20 are disposed at different locations on the vehicle 1. Furthermore, the detection range 30 of each of these multiple distance sensors 20 is adjusted so that at least a portion of it does not overlap.

[0032] Distance sensors 20FL, 20FLC, 20FRC, and 20FR are disposed on the front portion of vehicle 1. Distance sensors 20FL and 20FR are disposed at the corners of the front portion of vehicle 1. Distance sensor 20FL is disposed at the left corner of the front portion of vehicle 1. Distance sensor 20FR is disposed at the right corner of the front portion of vehicle 1. Distance sensor 20FLC is disposed on the left side of the center of the front portion of vehicle 1. Distance sensor 20FRC is disposed on the right side of the center of the front portion of vehicle 1.

[0033] The detection ranges 30FL, 30FLC, 30FRC, and 30FR of the range sensor 20FL, range sensor 20FLC, range sensor 20FRC, and range sensor 20FR are configured such that at least a portion of them are non-overlapping. Alternatively, the detection ranges 30 of each of these plurality of range sensors 20 may also be configured to partially overlap.

[0034] Distance sensors 20RL, 20RLC, 20RRC, and 20RR are located at the rear of vehicle 1. Distance sensors 20RL and 20RR are located at the corners of the rear of vehicle 1. Distance sensor 20RL is located at the left corner of the rear of vehicle 1. Distance sensor 20RR is located at the right corner of the rear of vehicle 1. Distance sensor 20RLC is located on the left side of the center of the rear of vehicle 1. Distance sensor 20RRC is located on the right side of the center of the rear of vehicle 1.

[0035] The detection ranges 30RL, 30RLC, 30RRC, and 30RR of the range sensor 20RL are configured such that at least a portion of them are non-overlapping. Alternatively, the detection ranges 30 of each of these plurality of range sensors 20 may also be configured to partially overlap.

[0036] Furthermore, the number and configuration of the ranging sensors 20 installed in the vehicle 1 are not limited to the above-described manner. For example, it is also possible to install one to three or four or more ranging sensors 20 in the front part of the vehicle 1, one to three or four or more ranging sensors 20 in the rear part of the vehicle 1, or one or more ranging sensors 20 in the side part of the vehicle 1.

[0037] The aforementioned multiple ranging sensors 20 detect objects within their respective detection ranges 30 and output the detection results to the object detection device 10.

[0038] An object is defined as an object that can be detected by the ranging sensor 20. For example, in this embodiment, an object is defined as an object that generates a reflected wave from an ultrasonic wave emitted from the ranging sensor 20.

[0039] Figure 2 This is a schematic diagram illustrating an example of the structure of the ranging sensor 20. The ranging sensor 20 includes a wave transmitter 22, a wave receiver 24, and a controller 26. The wave transmitter 22 and the wave receiver 24 are communicatively connected to the controller 26. The controller 26 is communicatively connected to the object detection device 10.

[0040] Wave transmitting unit 22 transmits ultrasonic waves. Wave receiving unit 24 receives ultrasonic waves reflected from objects. Wave transmitting unit 22 and wave receiving unit 24 transmit ultrasonic waves and receive reflected waves, for example, via piezoelectric elements. Controller 26 controls the wave transmission timing, wave transmission period, and frequency of the ultrasonic waves transmitted from wave transmitting unit 22. Furthermore, controller 26 measures the distance to the object by measuring the time from when the ultrasonic waves are transmitted by wave transmitting unit 22 to when the reflected waves are received by wave receiving unit 24. When an object is detected, controller 26 outputs detection result information to object detection device 10, including object detection information indicating object detection and distance information indicating the distance to the object.

[0041] return Figure 1 Continuing with the explanation, a camera device 40 and a radar 42 may also be installed in vehicle 1.

[0042] The camera device 40 captures images of the area surrounding the vehicle 1, obtaining photographic image data. Hereinafter, the photographic image data will be referred to simply as photographic images. The camera device 40 outputs the acquired photographic images to the object detection device 10.

[0043] In this embodiment, in vehicle 1, camera devices 40F and 40R are provided as camera devices 40. Camera device 40F is provided at the front of vehicle 1 and obtains photographic images of the front portion of the vehicle 1's perimeter. Camera device 40R is provided at the rear of vehicle 1 and obtains photographic images of the rear portion of the vehicle 1's perimeter. Furthermore, the number and arrangement of camera devices 40 provided in vehicle 1 are not limited to the above-described manner.

[0044] Radar 42 detects objects around vehicle 1 and measures the distance between the objects and vehicle 1. Radar 42 detects objects around vehicle 1 by scanning millimeter waves, which are electromagnetic waves. In this embodiment, radar 42F and radar 42R are provided in vehicle 1 as radar 42.

[0045] Radar 42F is installed at the front of vehicle 1, and detects objects in the front of vehicle 1 by scanning the area around the front of vehicle 1. Radar 42R is installed at the rear of vehicle 1, and detects objects in the rear of vehicle 1 by scanning the area around the rear of vehicle 1. Furthermore, the number and configuration of radars 42 installed on vehicle 1 are not limited to the above-described manner.

[0046] Next, the functional structure of the object detection system 100 will be described in detail.

[0047] Figure 3 This is a block diagram of an example of the functional structure of an object detection system 100.

[0048] Vehicle 1 is equipped with a distance measuring sensor 20, a camera device 40, a radar 42, a G sensor 44, a steering angle sensor 46, a driving control unit 48, an operation unit 50, an instrument computer 52, a storage unit 54, and an object detection device 10.

[0049] The ranging sensor 20, the camera device 40, the radar 42, the G-sensor 44, the rudder angle sensor 46, the driving control unit 48, the instrument computer 52, the storage unit 54, and the object detection device 10 are communicatively connected via a bus 56. For example, a local area network such as CAN (Controller Area Network) can be used in the bus 56.

[0050] The G-sensor 44 measures the acceleration of the vehicle 1 and outputs the measurement results to the object detection device 10. In this embodiment, the method of outputting the measurement results including the vehicle speed and acceleration of the vehicle 1 to the object detection device 10 will be described as an example of the G-sensor 44.

[0051] The steering angle sensor 46 detects the steering angle of the steering wheel installed on the vehicle 1 and outputs it as steering angle information to the object detection device 10.

[0052] The driving control unit 48 is an ECU (Engine Control Unit) that controls the driving of the vehicle 1. The driving control unit 48 is communicatively connected to the operation unit 50. Based on the operation information received from the operation unit 50 by the user, the driving control unit 48 controls the drive devices of the vehicle 1, such as the engine and motor, as well as the transmission system devices of the vehicle 1, such as the transmission.

[0053] The control unit 50 is operated by the driver, who is the user. The control unit 50 includes, for example, an ignition switch 50A, a gear shift lever 50B, an accelerator pedal 50C, and a brake pedal 50D. However, the control unit 50 mounted on the vehicle 1 is not limited to these.

[0054] The driving control unit 48 controls the drive unit and transmission system of the vehicle 1 based on the operation information of the ignition switch 50A, the shift position information of the gear shift lever 50B, the accelerator pedal operation information of the accelerator pedal 50C, and the brake pedal information of the brake pedal 50D. Furthermore, in this embodiment, the driving control unit 48 outputs the operation information of the ignition switch 50A and the shift position information of the gear shift lever 50B to the object detection device 10.

[0055] The operation information of the ignition switch 50A includes, for example, instructions on power supply to various parts of the vehicle 1's electrical system and instructions on starting the vehicle 1's engine. Upon receiving instructions on power supply to various parts of the vehicle 1's electrical system, the driving control unit 48 begins supplying power to the electronic devices mounted on the vehicle 1. Furthermore, upon receiving instructions on starting the vehicle 1's engine, the driving control unit 48 starts the engine of the vehicle 1.

[0056] The shift position information for shift lever 50B indicates the position of shift lever 50B. This shift position information may include, for example, parking, reverse, neutral, or drive.

[0057] The instrument computer 52 has an information reporting function for users such as drivers. The information reporting function includes displaying information and outputting audio messages to indicate information. Regarding the display function, for example, it could be a combination instrument unit that provides display-based reports to the driver. Regarding the audio output function, for example, it could be a report tone generating device that provides audio-based reports using a buzzer.

[0058] Storage unit 54 stores various types of data. Storage unit 54 may be, for example, a semiconductor memory element such as RAM (Random Access Memory), flash memory, a hard disk, or an optical disk. Storage unit 54 may also contain one or more storage media.

[0059] Next, the object detection device 10 will be described in detail.

[0060] Figure 4 This is a hardware structure diagram of an example of an object detection device 10.

[0061] In the object detection device 10, the CPU (Central Processing Unit) 11A, ROM (Read Only Memory) 11B, RAM 11C, and I / F 11D are interconnected via bus 11E, and the object detection device 10 utilizes the hardware structure of a typical computer.

[0062] CPU 11A is a computing device that controls the object detection device 10 of this embodiment. ROM 11B stores programs that implement various processes performed by CPU 11A. RAM 11C stores data required for various processes performed by CPU 11A. I / F 11D is an interface for sending and receiving data.

[0063] The program for performing the information processing executed in the object detection device 10 of this embodiment is pre-loaded into the ROM 11B or the like. Alternatively, the program executed in the object detection device 10 of this embodiment may also be configured to be a file that can be installed or executed in the object detection device 10, and recorded on a recording medium that can be read by a computer, such as a CD-ROM, floppy disk (FD), CD-R, or DVD (Digital Versatile Disk).

[0064] return Figure 3 Let's continue with the explanation.

[0065] The object detection device 10 controls the transmission of ultrasonic waves by each of the multiple ranging sensors 20.

[0066] Figure 5A as well as Figure 5B This is an illustrative diagram illustrating an example of conventional wave transmission control. In Figure 5A as well as Figure 5B The image shows an example of conventional wave transmission control for multiple ranging sensors 20 located at the rear of vehicle 1.

[0067] If ultrasonic waves are simultaneously emitted from multiple range sensors 20, it becomes impossible to distinguish which range sensor 20 the reflected ultrasonic wave originated from, leading to a decrease in distance measurement accuracy to object B. Therefore, ultrasonic waves are emitted sequentially from multiple range sensors 20 to detect object B.

[0068] For example, such as Figure 5A As shown, ultrasonic waves are transmitted sequentially in the order of ranging sensor 20RLC, ranging sensor 20RRC, ranging sensor 20RL, and ranging sensor 20RR. Ranging sensors 20RL and 20RR are respectively located at the two ends (corners) of vehicle 1 in the width direction, and are less affected by interference; therefore, ultrasonic waves are transmitted simultaneously.

[0069] In addition, to prevent false detections due to noise and improve reliability, when the same object B is detected more than a specified number of times, a process is performed to identify object B as the detected object.

[0070] For example, such as Figure 5A As shown, imagine a scenario where object B exists within the detection range 30RL of the range sensor 20RL. Furthermore, imagine a scenario where object B is detected more than three times by the same range sensor 20, and that object B is then identified as a detected object.

[0071] In this case, such as Figure 5BAs shown, the object B is detected three times by the ranging sensor 20RL based on the ultrasonic wave transmission timing of the last wave transmission of the first cycle C1, the second cycle C2, and the third cycle C3. For example, by the last ultrasonic wave transmission based on the ranging sensor 20RL and the ranging sensor 20RR in the third cycle C3, the object B located within the detection range 30RL of the ranging sensor 20RL is identified as the detected object. Therefore, in the prior art, the two wave transmissions from each of the ranging sensors 20RLLC and 20RRC in the initial first cycle C1 become useless wave transmissions X.

[0072] Therefore, in existing technologies, there is a time requirement before the object is determined to be a detected object. For example, in existing technologies, it is difficult to shorten the detection time for object B.

[0073] return Figure 3 The description continues. The object detection device 10 of this embodiment is a device that achieves reduced detection time and high-precision object detection for object B.

[0074] In detail, the object detection device 10 includes a processing unit 12. The processing unit 12 performs various information processing tasks. For example, the CPU 11A reads a program from the ROM 11B into the RAM 11C for execution, thereby implementing the various functional units of the processing unit 12, which will be described later, on a computer.

[0075] The processing unit 12 includes a vehicle status acquisition unit 12A, a wave transmission control unit 12B, a detection result acquisition unit 12C, an object detection unit 12D, a determination unit 12E, and a drive control unit 12F. Some or all of the vehicle status acquisition unit 12A, wave transmission control unit 12B, detection result acquisition unit 12C, object detection unit 12D, determination unit 12E, and drive control unit 12F can be implemented, for example, by executing a program using a processing device such as a CPU 11A, or by hardware such as an IC (Integrated Circuit), or by a combination of software and hardware. Alternatively, at least one of the vehicle status acquisition unit 12A, wave transmission control unit 12B, detection result acquisition unit 12C, object detection unit 12D, determination unit 12E, and drive control unit 12F can be mounted on an external information processing device communicatively connected to the object detection device 10 via a network or the like.

[0076] The vehicle status acquisition unit 12A acquires information indicating the vehicle status of vehicle 1.

[0077] The information indicating vehicle status refers to information indicating the state of vehicle 1. This information includes, for example, vehicle 1's speed, acceleration, steering angle, ignition switch 50A operation information, and gear shift position information. Furthermore, the information indicating vehicle status only needs to include at least the ignition switch 50A operation information and gear shift position information.

[0078] In this embodiment, the vehicle status acquisition unit 12A acquires the measurement results of the vehicle speed and acceleration of the vehicle 1 from the G sensor 44. Furthermore, the vehicle status acquisition unit 12A acquires steering angle information from the steering angle sensor 46. Additionally, the vehicle status acquisition unit 12A acquires the operation information of the ignition switch 50A and the shift position information of the gear shift lever 50B from the driving control unit 48.

[0079] The vehicle status acquisition unit 12A acquires vehicle speed, acceleration, steering angle information, ignition switch 50A operation information, and gear shift position information as information indicating the vehicle status.

[0080] The wave transmission control unit 12B sets the range sensor 20, which includes the area of ​​the object B detected in advance when the power supply to the vehicle 1 is started, as the detection range 30, as the beginning of the wave transmission sequence, and repeatedly performs periodic wave transmission control to send ultrasonic waves sequentially from each of the multiple range sensors 20 in accordance with the wave transmission sequence.

[0081] The term "pre-detection" refers to detecting the state of object B before performing periodic wave transmission control. Details of periodic wave transmission control will be described later.

[0082] The wave transmission control unit 12B performs a prior detection at least when power supply to the vehicle 1 begins. In this embodiment, the wave transmission control unit 12B performs the prior detection when power supply to the vehicle 1 begins and when the vehicle 1's vehicle status indicates a predetermined state, i.e., when the execution conditions are met.

[0083] The so-called execution conditions refer to the execution conditions detected in advance. The wave transmission control unit 12B uses the information indicating the vehicle status obtained by the vehicle status acquisition unit 12A to determine whether the execution conditions are met.

[0084] Specifically, the wave transmission control unit 12B determines whether the ignition switch 50A operation information included in the vehicle status information acquired by the vehicle status acquisition unit 12A is information indicating a power supply instruction to various parts of the vehicle 1's electrical system. If the information indicating a power supply instruction is included, the wave transmission control unit 12B determines that the execution condition is met. For example, when power supply to the vehicle 1 begins, the wave transmission control unit 12B determines that the execution condition is met.

[0085] Furthermore, the wave transmission control unit 12B can also determine whether the ignition switch 50A operation information included in the vehicle status information acquired by the vehicle status acquisition unit 12A contains information indicating an engine start instruction for vehicle 1. If the vehicle status information contains information indicating an engine start instruction for vehicle 1, the wave transmission control unit 12B can also determine that the execution condition is met.

[0086] Furthermore, if the shift position information of the shift lever 50B included in the vehicle status information acquired by the vehicle status acquisition unit 12A differs from the previously acquired shift position information, the wave transmission control unit 12B determines that the execution condition has been met. For example, when the shift lever 50B is operated according to an operation instruction given by the user, and the shift position is changed, the wave transmission control unit 12B determines that the execution condition has been met.

[0087] Furthermore, if at least one of the predetermined conditions of vehicle speed, vehicle acceleration, and rudder angle information of vehicle 1 is met, the wave transmission control unit 12B can also determine that the execution conditions are met.

[0088] When the wave transmission control unit 12B determines that the vehicle state of vehicle 1 meets the execution conditions, it performs a prior detection of object B.

[0089] In this embodiment, the wave transmission control unit 12B performs full-wave transmission control of the transmitted ultrasonic waves from multiple ranging sensors 20, thereby detecting the object B in advance.

[0090] Full-wave transmission control refers to the control of transmitting ultrasonic waves from multiple ranging sensors 20 mounted on vehicle 1. The ranging sensors 20 that are the object of full-wave transmission control can be all ranging sensors 20 mounted on vehicle 1, or multiple ranging sensors 20 belonging to a predetermined group.

[0091] For example, in the object detection device 10, ranging sensors 20 belonging to the group corresponding to the execution conditions are preset. Then, when the wave transmission control unit 12B determines that the execution conditions are met, it performs full-wave transmission control of all ranging sensors 20 belonging to the group corresponding to the determined execution conditions, thereby detecting the object B in advance.

[0092] For example, the object detection device 10 associates the execution conditions with the identification information of the ranging sensor 20 belonging to the group corresponding to the execution conditions and stores it in the storage unit 54.

[0093] Specifically, for example, the storage unit 54 pre-stores the execution condition "start power supply to vehicle 1" and associates it with the identification information of each of the distance sensors 20FL, 20FLC, 20FRC, and 20FR located at the front of vehicle 1. Furthermore, the storage unit 54 pre-stores the execution condition "shift position information 'reverse (backward)'" and associates it with the identification information of each of the distance sensors 20RL, 20RLC, 20RRC, and 20RR located at the rear of vehicle 1. Additionally, the storage unit 54 pre-stores the execution condition "shift position information 'forward driving (drive)'" and associates it with the identification information of each of the distance sensors 20FL, 20FLC, 20FRC, and 20FR located at the front of vehicle 1.

[0094] The wave transmission control unit 12B reads the identification information of the ranging sensor 20 corresponding to the determined execution condition from the storage unit 54, thereby determining multiple ranging sensors 20 belonging to the group corresponding to the determined execution condition. Then, the wave transmission control unit 12B performs full-wave transmission control to transmit ultrasonic waves from the determined multiple ranging sensors 20.

[0095] Furthermore, the ranging sensor 20 belonging to the group corresponding to the execution conditions is not limited to the above-described manner. In this embodiment, the following manner will be described as an example, wherein the identification information of the ranging sensor 20 belonging to the group corresponding to the execution conditions is associated with the above-described identification information and stored in the storage unit 54.

[0096] Ultrasonic waves are transmitted from multiple ranging sensors 20 via full-wave transmission control, thereby allowing object B to be detected in advance.

[0097] In detail, the detection result acquisition unit 12C acquires detection result information from each of the plurality of ranging sensors 20. As described above, the detection result information includes object detection information indicating that an object has been detected and distance information indicating the distance to the object. Furthermore, if no object is detected, the ranging sensor 20 only needs to output detection result information containing information indicating that no object has been detected to the object detection device 10.

[0098] The object detection unit 12D calculates the position of object B using the detection result information obtained from each of the multiple ranging sensors 20. The object detection unit 12D outputs the detection result information obtained from the detection result acquisition unit 12C, information indicating the position of object B, and identification information of the ranging sensor 20 that is the source of the detection result information to the wave transmission control unit 12B and the determination unit 12E.

[0099] The wave transmission control unit 12B determines the ranging sensor 20, which is identified by the identification information of the ranging sensor 20 of the transmission source containing the detection result information representing the object detection, as a ranging sensor 20 with a detection range 30 including the area containing the previously detected object B.

[0100] The wave transmission control unit 12B repeatedly performs periodic wave transmission control, with the ranging sensor 20, which includes the area containing the previously detected object B as the detection range 30, as the beginning of the wave transmission sequence.

[0101] The so-called repeated periodic wave transmission control refers to the periodic and repeated execution of a series of wave transmission controls that cause each of the multiple ranging sensors 20 to transmit ultrasonic waves in a predetermined wave transmission order.

[0102] The wave transmission control unit 12B sets the ranging sensor 20, which has previously detected object B, as the ranging sensor 20 that transmits ultrasonic waves at the beginning of each cycle of the wave transmission sequence in the periodic wave transmission control. Then, the wave transmission control unit 12B repeatedly performs periodic wave transmission control C, which sets the ranging sensor 20 as the beginning of the wave transmission sequence.

[0103] When any of the multiple range sensors 20 detects an object B a predetermined number of times, the determination unit 12E determines that the object B is a detected object. Determining it as a detected object means identifying the object B detected by the range sensor 20 as a detected object B to be used in post-processing in the drive control unit 12F, etc.

[0104] The predetermined number of times that object B is identified as a detection object can be determined in advance. In this embodiment, the case where the predetermined number is three times will be described as an example. In addition, the predetermined number is not limited to three times, as long as it is multiple times. Furthermore, in this embodiment, "predetermined number of times" will be defined as the number of times that object B is identified as a detection object.

[0105] Figure 6A as well as Figure 6B This is an explanatory diagram illustrating an example of wave transmission control in this embodiment. In Figure 6A as well as Figure 6B In the diagrams illustrating wave transmission control described later, unless otherwise specified, a scenario where the shift position information of shift lever 50B indicates "reverse (backward)" will be shown as an example. Furthermore, in Figure 6A as well as Figure 6BIn the explanatory diagram of wave transmission control described later, the following method is shown as an example: wave transmission control is performed on the range sensors 20RL, 20RLC, 20RRC, and 20RR located at the rear of the vehicle 1, which belong to the group corresponding to the execution condition indicating "reverse (backward)". Furthermore, in Figure 6A as well as Figure 6B The example shown is a scenario where object B exists within the detection range 30RL of the ranging sensor 20RL. Figure 6B In the diagram, the horizontal axis represents time t.

[0106] For example, when the shift position information of the shift lever 50B indicates "reverse (backward)" and the execution condition is met, the wave transmission control unit 12B performs full-wave transmission control F on these multiple ranging sensors 20, so that ultrasonic waves are transmitted from each of the ranging sensors 20RL, 20RLC, 20RRC, and 20RR. Figure 6A Step S10).

[0107] Ultrasonic waves are transmitted from each of the ranging sensors 20RL, 20RLC, 20RRC, and 20RR using the full-wave transmission control F based on the wave transmission control unit 12B. For example, as Figure 6B As shown, in the full-wave transmission control F, ultrasonic waves are simultaneously transmitted from each of the ranging sensors 20RL, 20RLC, 20RRC, and 20RR during the same timing and the same wave transmission period.

[0108] exist Figure 6A as well as Figure 6B In the example shown, the ranging sensor 20RL detects object B through prior detection based on the full-wave transmission control F. Therefore, the wave transmission control unit 12B sets the ranging sensor 20RL, which has detected object B through prior detection, as the ranging sensor 20 that transmits ultrasonic waves at the beginning of the wave transmission sequence of each cycle in the periodic wave transmission control C.

[0109] Then, the wave transmission control unit 12B takes the distance sensor 20RL, which has detected the object B in advance, as the starting point, and repeatedly performs periodic wave transmission control C on each of the distance sensors 20RL, 20RLC, 20RRC, and 20RR, which belong to the group corresponding to the shift position information "backward (reverse)" of the shift lever 50B, so that the ultrasonic waves are transmitted sequentially in a predetermined wave transmission order.

[0110] For example, consider a scenario where the wave transmission sequence is predetermined as follows: ranging sensor 20RLC, ranging sensor 20RRC, ranging sensor 20RL, and ranging sensor 20RR. In this case, the wave transmission control unit 12B starts with the ranging sensor 20RL, which has detected object B through prior detection, and repeatedly performs periodic wave transmission control C, sequentially transmitting ultrasonic waves in the order of ranging sensor 20RL, ranging sensor 20RR, ranging sensor 20RLC, and ranging sensor 20RRC. Figure 6A Steps S11 to S13).

[0111] By repeatedly transmitting periodic waves to control C, thus... Figure 6B As shown, at the beginning of each wave transmission control C in the first cycle C1, the second cycle C2, and the third cycle C3, the ranging sensor 20RL and the ranging sensor 20RR transmit ultrasonic waves. As described above, in this embodiment, the case of three predetermined transmissions will be explained as an example. Therefore, when the determination unit 12E transmits ultrasonic waves from the ranging sensor 20RL and the ranging sensor 20RR at the initial wave transmission timing of the third cycle C3, it determines the object B located within the detection range 30RL detected by the wave transmission as the detected object.

[0112] Therefore, the object detection device 10 of this embodiment does not require the following: Figure 5A as well as Figure 5B The useless wave transmission X from each of the range sensors, such as the range sensor 20RLC and range sensor 20RRC, in the initial first cycle C1, as described in the prior art, can identify an object B that has been detected a predetermined number of times by the range sensor 20RL as a detected object. For example, the object detection device 10 of this embodiment does not require operation and use. Figure 5A as well as Figure 5B The prior art, which describes the useless wave transmission X corresponding to two wave transmissions, can identify an object B located within the detection range 30RL of the ranging sensor 20RL as a detected object. Furthermore, when the duration of the full-wave transmission control F is equivalent to the wave transmission time of an ultrasonic wave corresponding to one transmission, the object detection device 10 of this embodiment can shorten the time corresponding to one wave transmission.

[0113] For example, in the periodic wave transmission control C, the object detection apparatus 10 of this embodiment prioritizes the detection range 30 that detects object B through prior detection based on the full-wave transmission control F. Therefore, the object detection apparatus 10 of this embodiment can shorten the time required to determine object B as a detection object. Furthermore, since the object detection apparatus 10 of this embodiment determines object B as a detection object after detecting it a predetermined number of times, it can suppress false determinations and determine object B as a detection object with high accuracy.

[0114] return Figure 3 The explanation continues. The drive control unit 12F performs drive control on the vehicle 1 based on the determination result of the determination unit 12E.

[0115] For example, the drive control unit 12F controls the driving control unit 48 to avoid contact with object B, which is determined by the determination unit 12E to be a detection object. For example, the drive control unit 12F controls the driving control unit 48 to drive while avoiding contact with object B, which is determined to be a detection object. In this case, the driving control unit 48 controls the vehicle 1 to drive while avoiding contact with object B, which is determined to be a detection object. Furthermore, the drive control unit 12F controls the driving control unit 48 to stop to avoid contact with object B, which is determined to be a detection object. In this case, the driving control unit 48 controls the vehicle 1 to stop driving while avoiding contact with object B, which is determined to be a detection object.

[0116] Furthermore, the drive control unit 12F can also output information related to the object B that the determination unit 12E has determined to be a detected object to the instrument computer 52. For example, the drive control unit 12F can also display or output sound information indicating that the determined object B is located within the detection range 30 to the instrument computer 52.

[0117] In addition, there may be cases where multiple objects B are detected in advance. In this case, the wave transmission control unit 12B only needs to repeatedly perform periodic wave transmission control C, which starts the wave transmission sequence with the ranging sensor 20, whose detection range 30 includes the area of ​​the object B located at the closest distance to the vehicle 1.

[0118] Figure 7 This is an illustrative diagram illustrating an example of wave transmission control in a scenario where multiple objects B are detected beforehand. Figure 7 In the example shown, an object B (object B1 to object B4) is present in each of the detection ranges 30RL, 30RLC, 30RRC, and 30RR of the range sensor 20RL and the range sensor 20RR, respectively.

[0119] For example, the wave transmission control unit 12B performs full-wave transmission control F on these multiple ranging sensors 20 to transmit ultrasonic waves from each of the ranging sensors 20RL, 20RLC, 20RRC, and 20RR (step S14).

[0120] Through the full-wave transmission control F in step S14, each of the ranging sensors 20RL, 20RLC, 20RRC, and 20RR detects object B. Thus, there is a possibility that object B may be detected in advance by multiple ranging sensors 20.

[0121] In this case, the wave transmission control unit 12B determines the object B among the multiple objects B detected beforehand that is closest to the vehicle 1. For example, the wave transmission control unit 12B determines the object B closest in distance, as indicated by the distance information contained in the detection result information received from the object detection unit 12D. Figure 7 In the example shown, the wave transmission control unit 12B determines the object B2 closest to the vehicle 1. Then, the wave transmission control unit 12B sets the ranging sensor 20RLC that detected the object B2 to transmit ultrasonic waves at the beginning of each cycle of the wave transmission sequence in the periodic wave transmission control C. For example, the wave transmission control unit 12B sets the ranging sensor 20RLC that detected the object B2, which is located closest to the vehicle 1, through prior detection, to transmit ultrasonic waves at the beginning of each cycle of the periodic wave transmission control C.

[0122] Then, the wave transmission control unit 12B takes the ranging sensor 20RLC as the beginning of the wave transmission sequence and repeatedly performs periodic wave transmission control C (steps S15 to S17) to send ultrasonic waves sequentially from each ranging sensor 20RL, ranging sensor 20RLC, ranging sensor 20RRC and ranging sensor 20RR according to a predetermined wave transmission sequence.

[0123] Thus, when an object B is detected in advance by multiple ranging sensors 20, the wave transmission control unit 12B repeatedly performs periodic wave transmission control C, starting with the ranging sensors 20 whose detection range 30 includes the area containing the object B located closest to the vehicle 1. Therefore, in this case, the object detection device 10 can preferentially identify the object B located closest to the vehicle 1 as the detection object.

[0124] Furthermore, the wave transmission control unit 12B can also repeatedly perform periodic wave transmission control C after controlling the ranging sensor 20, which has a detection range 30 including the area of ​​the object B detected in advance by the full-wave transmission control F, to perform a predetermined number of wave transmissions. For example, the wave transmission control unit 12B can also repeatedly perform periodic wave transmission control C after controlling the ranging sensor 20, which has detected the object B in advance, to perform the same number of wave transmissions as the predetermined number used when determining the object B as a detected object.

[0125] Figure 8 This is an illustrative diagram illustrating an example of wave transmission control. In Figure 8 The image shows the detection of object B by the ranging sensor 20RL through prior detection based on full-wave transmission control F. Furthermore, in... Figure 8 The diagram illustrates the wave transmission control process where, after controlling the ranging sensor 20RL to transmit waves a predetermined number of times, the periodic wave transmission control C is repeatedly performed. Figure 8 In the diagram, the horizontal axis represents time t.

[0126] Ultrasonic waves are transmitted from ranging sensors 20RLC, 20RRC, 20RL, and 20RR via full-wave transmission control F based on the wave transmission control unit 12B. Then, consider a scenario where object B is detected by ranging sensor 20RL through prior detection based on the full-wave transmission control F. In this case, the wave transmission control unit 12B uses the ranging sensor 20RL, which detected object B through prior detection, as the beginning of the wave transmission sequence, and continuously transmits ultrasonic waves from ranging sensors 20RL and 20RR a predetermined number of times (e.g., three times). Then, the wave transmission control unit 12B repeatedly performs periodic wave transmission control C, using the ranging sensor 20RL, which detected object B through prior detection, as the beginning of the wave transmission sequence.

[0127] In this way, the wave transmission control unit 12B can also repeatedly perform the periodic wave transmission control C, which uses the ranging sensor 20RL as the beginning of the wave transmission sequence, after continuously transmitting ultrasonic waves a predetermined number of times from the ranging sensor 20RL that has detected the object B through prior detection, at the beginning of the first periodic wave transmission control C of the first period C1. In this case, the object detection device 10 can further shorten the time required to determine the object B as the detected object.

[0128] Furthermore, when any one of the multiple ranging sensors 20 in the periodic wave transmission control C detects object B a predetermined number of times, the determination unit 12E determines that object B is a detected object. For example, the determination unit 12E determines the ranging sensor 20 that has detected object B a predetermined number of times through the repeated execution of the periodic wave transmission control C as the ranging sensor 20 that has detected the detected object. Then, the determination unit 12E determines the object B detected by that ranging sensor 20 as the detected object.

[0129] Here, when only one ranging sensor 20 detects object B via the full-wave transmission control F based on the wave transmission control unit 12B, it is considered that even if ultrasonic waves are simultaneously transmitted from multiple ranging sensors 20 in the full-wave transmission control F, no interference from reflected waves will occur. Therefore, when object B is detected by only one ranging sensor 20 via the full-wave transmission control F, the determination unit 12E can also count the number of times object B is detected in the full-wave transmission control F as once within a predetermined number. For example, the determination unit 12E can also determine object B as a detected object when any of the multiple ranging sensors 20 in the full-wave transmission control F and the periodic wave transmission control C detects object B a predetermined number of times.

[0130] Figure 9 This is an explanatory diagram of an example of wave transmission control where the number of times object B is detected based on full-wave transmission control F is also counted as a predetermined number. Figure 9 In the diagram, the horizontal axis represents time t.

[0131] Ultrasonic waves are transmitted from ranging sensors 20RLC, 20RRC, 20RL, and 20RR via full-wave transmission control F based on the wave transmission control unit 12B. Then, consider a scenario where, through prior detection based on the full-wave transmission control F, ranging sensor 20RL detects object B. In this case, the wave transmission control unit 12B repeatedly performs periodic wave transmission control C, starting with the ranging sensor 20RL that detected object B through prior detection as the beginning of the wave transmission sequence.

[0132] Then, when the total number of times that the ranging sensor 20RL detects object B through the full-wave transmission control F and the number of times that the ranging sensor 20RL detects object B through the periodic wave transmission control C reaches a predetermined number, the determination unit 12E determines object B as a detected object.

[0133] In this way, the determination unit 12E can also determine that object B is a detected object when any of the ranging sensors 20 in the full-wave transmission control F and the periodic-wave transmission control C detects object B a predetermined number of times. By including the number of times object B is detected in the full-wave transmission control F in the counting, the object detection device 10 can further shorten the time required to determine object B as a detected object.

[0134] Alternatively, the wave transmission control unit 12B can also detect the object B in advance using an object detection sensor other than the ranging sensor 20. The object detection sensor other than the ranging sensor 20 is, for example, at least one of the camera device 40 and the radar 42. In this case, the wave transmission control unit 12B can detect the object B in advance simply by detecting the object B contained in the photographic image captured by the camera device 40 and the object B detected by at least one of the radars 42, for example, when the execution conditions are met, such as when power supply to the vehicle 1 begins.

[0135] Then, the wave transmission control unit 12B repeatedly performs the periodic wave transmission control C, which uses the ranging sensor 20, which detects the object B through prior detection, as the beginning of the wave transmission sequence.

[0136] Figure 10 This is an illustrative diagram illustrating an example of transmission control based on the prior detection of object B by an object detection sensor. Figure 10 In the diagram, the horizontal axis represents time t.

[0137] Imagine a scenario where object B is detected within the detection range 30RL of the range sensor 20RL through prior detection by an object detection sensor such as the camera device 40. In this case, the wave transmission control unit 12B only needs to repeatedly perform periodic wave transmission control C, starting with the range sensor 20RL, whose detection range 30RL includes the area containing the previously detected object B, as the beginning of the wave transmission sequence.

[0138] Even when prior detection is performed using a sensor other than the ranging sensor 20, the periodic wave transmission control C, which starts with the ranging sensor 20RL (which includes the area 30RL of the previously detected object B) as the beginning of the wave transmission sequence, is repeatedly performed. This shortens the time required to determine that object B is a detected object.

[0139] Additionally, if using the above Figure 6B , Figure 8 as well as Figure 9As will be explained later, the wave transmission control unit 12B can also control the simultaneous transmission of ultrasonic waves from multiple ranging sensors 20 in the full-wave transmission control F. Furthermore, the wave transmission control unit 12B can also sequentially transmit ultrasonic waves from multiple ranging sensors 20 at at least a portion of non-overlapping timings in the full-wave transmission control F.

[0140] Figure 11 This is an explanatory diagram illustrating an example of the wave transmission control flow based on the wave transmission control unit 12B. In Figure 11 In the diagram, the horizontal axis represents time t.

[0141] The wave transmission control unit 12B, for example, transmits ultrasonic waves from the range sensor 20RLC, range sensor 20RRC, range sensor 20RL, and range sensor 20RR via the full-wave transmission control F.

[0142] The wave transmission control unit 12B can also, within the full-wave transmission control F, sequentially transmit ultrasonic waves from multiple ranging sensors 20 at at least a portion of non-overlapping timings. In this case, the wave transmission control unit 12B preferably performs full-wave transmission control F, transmitting ultrasonic waves from each of the multiple ranging sensors 20 at a wave transmission time Tb less than the wave transmission time Ta from each ranging sensor 20 in the periodic wave transmission control C, and in a manner where at least a portion of their respective wave transmission periods overlap.

[0143] Furthermore, the total wave transmission period Tc of the ultrasonic waves from the multiple ranging sensors 20 in the full-wave transmission control F is preferably less than twice the wave transmission time Ta of each wave from the ranging sensor 20 in the periodic wave transmission control C.

[0144] By making the wave transmission time Tb of the ultrasonic waves transmitted from each of the multiple ranging sensors 20 in the full-wave transmission control F shorter than the wave transmission time Ta of each ranging sensor 20 in the periodic wave transmission control C, the time of the full-wave transmission control F can be shortened. Therefore, in this case, the object detection device 10 can shorten the time required to determine that object B is a detected object.

[0145] In addition, the wave transmission control unit 12B can also control the transmission of ultrasonic waves of different frequencies to each of the multiple ranging sensors 20 installed on the vehicle 1 that are divided into multiple predetermined groups.

[0146] The groups with different frequencies can be the same as or different from the groups corresponding to the execution conditions described above. In this embodiment, we will describe an example where the groups with different frequencies are the same as the groups corresponding to the execution conditions described above.

[0147] In the wave transmission control unit 12B, each ranging sensor 20 belonging to a group is preset with a frequency that is different from that of the group.

[0148] For example, the wave transmission control unit 12B pre-classifies the multiple ranging sensors 20 installed on the vehicle 1 into groups based on ranging sensors 20FL, 20FLC, 20FRC, and 20FR installed on the front part of the vehicle 1, and groups based on ranging sensors 20RL, 20RLC, 20RRC, and 20RR installed on the rear part of the vehicle 1. Then, the wave transmission control unit 12B pre-sets each ranging sensor 20 belonging to these multiple groups to use ultrasonic waves at frequencies different from those in the groups.

[0149] Then, the wave transmission control unit 12B performs control so that when the full-wave transmission control F and the periodic wave transmission control C are controlled respectively, ultrasonic waves of different frequencies are transmitted in each group.

[0150] Figure 12 This is an explanatory diagram of an example of multiple vehicles 1 equipped with the object detection device 10 of this embodiment. Figure 12 In the illustration, vehicles 1A and 1B, which are traveling in the direction of travel (arrow Z), are shown as examples. Vehicles 1A and 1B are examples of vehicle 1.

[0151] For example, imagine a scenario where vehicles 1A and 1B are traveling in the direction of arrow Z, and ultrasonic waves are transmitted from each of the multiple ranging sensors 20 installed on vehicle 1. Even in such a case, the wave transmission control unit 12B controls the transmission to transmit ultrasonic waves of different frequencies to each group of the multiple ranging sensors 20, thereby suppressing interference from ultrasonic waves transmitted from other vehicles 1.

[0152] Specifically, for example, consider a scenario where the ultrasonic waves emitted from each of the multiple ranging sensors 20 installed in vehicle 1 all have the same frequency. In this case, the ultrasonic waves emitted from the ranging sensors 20 (ranging sensors 20RL, 20RLC, 20RRC, and 20RR) installed in the rear part of vehicle 1A have the same frequency as the ultrasonic waves emitted from the ranging sensors 20 (ranging sensors 20FL, 20FLC, 20FRC, and 20FR) installed in the front part of vehicle 1B, thus causing interference.

[0153] On the other hand, in this embodiment, the wave transmission control unit 12B controls the transmission of ultrasonic waves of different frequencies from the ranging sensors 20 (ranging sensors 20RL, 20RLC, 20RRC, and 20RR) located at the rear of vehicle 1 and the ranging sensors 20 (ranging sensors 20FL, 20FLC, 20FRC, and 20FR) located at the front of vehicle 1. This control ensures that the ultrasonic waves transmitted from the ranging sensors 20 (ranging sensors 20RL, 20RLC, 20RRC, and 20RR) located at the rear of vehicle 1A are at different frequencies from the ultrasonic waves transmitted from the ranging sensors 20 (ranging sensors 20FL, 20FLC, 20FRC, and 20FR) located at the front of vehicle 1B, thus suppressing interference.

[0154] Therefore, according to this embodiment, the wave transmission control unit 12B can suppress interference from ultrasonic waves transmitted between different vehicles 1 even when performing full-wave transmission control F and periodic wave transmission control C from all the ranging sensors 20 mounted on the vehicle 1, regardless of the shift position information of the vehicle 1. Thus, in the object detection system 100, ultrasonic waves can be transmitted from all the ranging sensors 20 mounted on the vehicle 1 at all times, thereby improving responsiveness.

[0155] Next, an example of the information processing flow performed in the object detection device 10 of this embodiment will be described.

[0156] Figure 13 This is a flowchart illustrating an example of the information processing flow performed in the object detection device 10. Additionally, Figure 13 The information processing flow executed when the ignition switch 50A of vehicle 1 is operated by the user to start the power supply to vehicle 1 will be described as an example.

[0157] If power supply to vehicle 1 is initiated, the wave transmission control unit 12B determines the group of ranging sensors 20 corresponding to the execution condition "start power supply to vehicle 1" (step S100). For example, the wave transmission control unit 12B determines the ranging sensors 20FL, 20FLC, 20FRC, and 20FR installed on the front part of vehicle 1 as the ranging sensors 20 corresponding to the execution condition "start power supply to vehicle 1".

[0158] Next, the wave transmission control unit 12B performs full-wave transmission control F for all of the multiple ranging sensors 20 belonging to the determined group to transmit ultrasonic waves, thereby detecting the object B in advance (step S102).

[0159] The wave transmission control unit 12B determines whether object B has been detected by a ranging sensor 20 through the full-wave transmission control F in step S102 (step S104). If object B has been detected by a ranging sensor 20 (step S104: yes), the process proceeds to step S106.

[0160] In step S106, the wave transmission control unit 12B sets the ranging sensor 20, which detects the object B through the prior detection based on the full-wave transmission control F in step S102, to transmit ultrasonic waves at the beginning of the wave transmission sequence of each cycle in the periodic wave transmission control C (step S106). Then, it proceeds to step S110.

[0161] On the other hand, if object B is detected by the multiple ranging sensors 20 through the full-wave transmission control F in step S102 (step S104: No), proceed to step S108. In step S108, the wave transmission control unit 12B sets the ranging sensor 20 that detected the object B closest to vehicle 1 among the multiple ranging sensors 20 to be the ranging sensor 20 that transmits ultrasonic waves at the beginning of the wave transmission sequence of each cycle in the periodic wave transmission control C (step S108). Then, proceed to step S110.

[0162] In step S110, the wave transmission control unit 12B sets the ranging sensor 20, which was set as the start in step S106 or step S108, as the start of the wave transmission sequence, and begins to perform periodic wave transmission control C (step S110) in which multiple ranging sensors 20 belonging to the group corresponding to the execution conditions transmit ultrasonic waves in sequence.

[0163] Next, the wave transmission control unit 12B determines whether the execution conditions are met (step S112). In step S112, the wave transmission control unit 12B determines whether the vehicle state obtained by the vehicle state acquisition unit 12A meets the execution conditions that are different from the execution conditions used in the full-wave transmission control F in step S102.

[0164] If a negative judgment is made in step S112 (step S112: no), then proceed to step S114.

[0165] In step S114, the determination unit 12E determines whether object B has been detected a predetermined number of times by any of the multiple ranging sensors 20 (step S114). If a negative determination is made in step S114 (step S114: No), the process returns to step S112 above and continues with the periodic wave transmission control C. If a positive determination is made in step S114 (step S114: Yes), the process proceeds to step S116.

[0166] In step S116, the object B located within the detection range 30 of the ranging sensor 20, which has detected the object B a specified number of times in step S114, is determined to be the detected object (step S116).

[0167] Based on the determination result of step S116, the drive control unit 12F performs drive control on the vehicle 1 (step S118).

[0168] Next, the processing unit 12 determines whether to terminate the wave transmission control processing of the ranging sensor 20 (step S120). For example, the processing unit 12 determines whether a signal indicating the termination of power supply to the vehicle 1 has been input through operation of the ignition switch 50A by the user, and thus executes the determination in step S120. If a negative determination is made in step S120 (step S120: No), the process returns to step S112. If a positive determination is made in step S120 (step S120: Yes), the process proceeds to step S122.

[0169] In step S122, the wave transmission control unit 12B ends the periodic wave transmission control C (step S122), thus ending this routine.

[0170] On the other hand, if a positive judgment is made in step S112 (step S112: Yes), then the process proceeds to step S124. In step S124, the wave transmission control unit 12B ends the periodic wave transmission control C (step S124). Then, the wave transmission control unit 12B determines the group of ranging sensors 20 corresponding to the execution conditions determined in step S112 (step S126) and proceeds to the aforementioned step S102.

[0171] As explained above, the object detection system 100 of this embodiment includes a plurality of ranging sensors 20, a wave transmission control unit 12B, and a determination unit 12E. The plurality of ranging sensors 20 each has a wave transmission unit 22 that transmits ultrasonic waves and a wave receiving unit 24 that receives reflected waves of ultrasonic waves reflected by an object B, and detects the object B based on the reflected waves. The plurality of ranging sensors 20 are arranged at different locations on the vehicle 1. The wave transmission control unit 12B sets the ranging sensor 20 among the plurality of ranging sensors 20 whose detection range 30 includes the area of ​​the object B previously detected when power supply to the vehicle 1 begins, as the beginning of the wave transmission sequence, and repeatedly performs periodic wave transmission control C, which causes each ranging sensor of the plurality of ranging sensors 20 to sequentially transmit ultrasonic waves according to this wave transmission sequence. The determination unit 12E determines the object B as a detected object when any of the plurality of ranging sensors 20 detects the object B a predetermined number of times.

[0172] In the prior art, periodic wave transmission control is repeatedly performed, sequentially transmitting ultrasonic waves from multiple range sensors 20 in a wave transmission order that always starts with the same range sensor 20. Then, if object B is detected by the same range sensor 20 more than a predetermined number of times, object B is identified as a detected object. Therefore, in the prior art, when the range sensor 20, which transmits ultrasonic waves at intervals other than the beginning of each cycle of periodic wave transmission control, detects object B, useless wave transmission X is generated, and the time required to identify object B as a detected object becomes longer. Furthermore, as a prior art, a technique is disclosed to shorten the object detection time by reducing the number of determinations when an object is detected by an image from an infrared camera. However, in such a prior art, since the number of determinations is varied, false determinations may occur, making it difficult to identify object B as a detected object with high accuracy.

[0173] On the other hand, in the object detection system 100 of this embodiment, after the wave transmission control unit 12B sets the range sensor 20, whose detection range 30 includes the area of ​​the object B detected in advance when the power supply to the vehicle 1 begins, as the beginning of the wave transmission sequence, it repeatedly performs periodic wave transmission control C, in which each of the plurality of range sensors 20 sequentially transmits ultrasonic waves according to the wave transmission sequence. Then, the determination unit 12E determines the object B as a detected object when any of the plurality of range sensors 20 detects the object B a predetermined number of times.

[0174] For example, in the object detection system 100 of this embodiment, the detection range 30 of object B, which is detected in advance, takes priority over the detection range 30 of other ranging sensors 20 in the periodic wave transmission control C. Therefore, the object detection device 10 of this embodiment can shorten the time required to determine object B as a detection object. Furthermore, since the object detection device 10 of this embodiment determines object B as a detection object after detecting it a predetermined number of times, it can suppress false determinations and determine object B as a detection object with high accuracy.

[0175] Therefore, the object detection system 100 of this embodiment can achieve shortened detection time and high-precision object detection.

[0176] Furthermore, the object detection system 100 of this embodiment detects the object B in advance by controlling the full-wave transmission F of the transmitted ultrasonic waves from multiple ranging sensors 20. Therefore, the object detection system 100 of this embodiment can achieve both advance detection and periodic wave transmission control C through the control of the ranging sensors 20. Thus, in this embodiment, compared to the case where multiple sensors are used for advance detection and periodic wave transmission control C, a versatile object detection system 100 capable of handling adjustments to sensor mounting positions, specification changes, etc., can be provided. Furthermore, the object detection system 100 of this embodiment achieves cost reduction.

[0177] In this embodiment, the object detection device 10 is described as being mounted on the vehicle 1 as an example. However, the object detection device 10 can also be an external structure mounted on the vehicle 1. The object detection device 10 only needs to be communicatively connected to various electronic devices installed on the vehicle 1, such as the ranging sensor 20, camera device 40, radar 42, G-sensor 44, steering angle sensor 46, driving control unit 48, instrument computer 52, and storage unit 54. Therefore, the object detection device 10 can also be an external information processing device mounted on the vehicle 1. In this case, it is sufficient to configure the information processing device equipped with the object detection device 10 and the aforementioned electronic devices to communicate via a network or the like.

[0178] Furthermore, while embodiments have been described above, they are merely examples and not intended to limit the scope of the invention. The new embodiments described above can be implemented in a wide variety of other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. The above embodiments are included within the scope or spirit of the invention, and are also included within the scope of the invention and its equivalents as described in the protection scope of this invention.

Claims

1. An object detection system comprising: a plurality of distance measuring sensors disposed at mutually different positions of a vehicle, the distance measuring sensor having a wave transmitting section that transmits an ultrasonic wave and a wave receiving section that receives a reflected wave of the ultrasonic wave reflected by an object, and detecting the object based on the reflected wave; a wave transmission control section that, when power supply to the vehicle is started and when a vehicle state of the vehicle indicates a predetermined state, that is, when an execution condition is satisfied, performs full wave transmission control of transmitting the ultrasonic wave from a plurality of the distance measuring sensors belonging to a predetermined group, sets a distance measuring sensor having a detection range including an object detected in advance as a start of a wave transmission order, and repeatedly performs periodic wave transmission control of sequentially transmitting the ultrasonic wave in the order from each of the plurality of the distance measuring sensors; and a determination section that, when an object is detected a predetermined number of times by any of the plurality of the distance measuring sensors, determines the object as a detection object.

2. The object detection system according to claim 1, wherein the wave transmission control section performs: the full wave transmission control of transmitting the ultrasonic wave from a plurality of the distance measuring sensors belonging to the group corresponding to the execution condition when the execution condition is satisfied, and the periodic wave transmission control of sequentially transmitting the ultrasonic wave in the order from each of the plurality of the distance measuring sensors belonging to the group corresponding to the execution condition after the distance measuring sensor having the detection range including the object detected in advance by the full wave transmission control is set as the start of the wave transmission order.

3. The object detection system according to claim 2, wherein the wave transmission control section, when the execution condition is satisfied, performs the full wave transmission control of transmitting the ultrasonic wave from each of the plurality of the distance measuring sensors belonging to the group in a wave transmission time shorter than each wave transmission time in the periodic wave transmission control and in a manner in which at least a part of wave transmission periods overlap.

4. The object detection system according to claim 3, wherein a total wave transmission period of the ultrasonic wave from the plurality of the distance measuring sensors in the full wave transmission control is shorter than twice each wave transmission time of the distance measuring sensor in the periodic wave transmission control.

5. The object detection system according to claim 1 or 2, wherein the wave transmission control section, after performing control to cause the wave transmission from the distance measuring sensor having the detection range including the object detected in advance by the full wave transmission control a predetermined number of times, repeatedly performs the periodic wave transmission control.

6. The object detection system according to claim 1 or 2, wherein the wave transmission control section, when a plurality of objects are detected in advance, after setting the distance measuring sensor having a detection range including an object located closest to the vehicle among the plurality of objects as the start of the wave transmission order, repeatedly performs the periodic wave transmission control. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 7. The object detection system according to claim 1 or 2, wherein the determination section determines the object as the detected object when any one of the plurality of distance sensors detects the object the prescribed number of times in the periodic wave transmission control.

8. The object detection system according to claim 1 or 2, wherein the determination section determines the object as the detected object when any one of the plurality of distance sensors detects the object the prescribed number of times in the prior detection and the periodic wave transmission control.

9. The object detection system according to claim 1, wherein the wave transmission control section, when the execution condition is satisfied at the start of the electric power supply to the vehicle and when the vehicle state of the vehicle indicates the prescribed state, repeatedly performs the periodic wave transmission control after setting the distance sensor that takes a region including the object detected by the object detection sensor as a detection range at the beginning of the wave transmission order.

10. The object detection system according to claim 1 or 2, wherein the wave transmission control section controls so that each of groups obtained by classifying the plurality of distance sensors provided to the vehicle into a predetermined number of groups transmits ultrasonic waves of mutually different frequencies.

11. An object detection method, performing, in a plurality of distance sensors provided to a vehicle at mutually different positions, full wave transmission control of transmitting ultrasonic waves from a plurality of distance sensors belonging to a predetermined group when an execution condition is satisfied at the start of electric power supply to the vehicle and when a vehicle state of the vehicle indicates a prescribed state, by the full wave transmission control, setting a distance sensor that takes a region including an object detected in advance as a detection range at the beginning of a wave transmission order; repeating, in each of the plurality of distance sensors, periodic wave transmission control of sequentially transmitting ultrasonic waves in accordance with the wave transmission order; and determining, when any one of the plurality of distance sensors detects an object the prescribed number of times, the object as a detected object.

12. An object detection device, comprising: a wave transmission control section that, when an execution condition is satisfied at the start of electric power supply to a vehicle and when a vehicle state of the vehicle indicates a prescribed state, performs full wave transmission control of transmitting ultrasonic waves from a plurality of distance sensors belonging to a predetermined group, by the full wave transmission control, sets a distance sensor that takes a region including an object detected in advance as a detection range at the beginning of a wave transmission order, and repeatedly performs periodic wave transmission control of sequentially transmitting ultrasonic waves in accordance with the wave transmission order from each of the plurality of distance sensors; and a determination section that determines, when any one of the plurality of distance sensors detects an object the prescribed number of times, the object as a detected object, the plurality of distance sensors are provided to the vehicle at mutually different positions, the distance sensor has a transmission section that transmits ultrasonic waves and a wave reception section that receives a reflected wave of the ultrasonic waves reflected by an object.

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