Correction system

Abstract

This correction system includes a first imaging device, a second imaging device, and a server. The first imaging device comprises: a first imaging unit that images, by each of a pair of imaging elements, an object image of the same object for which an image was formed by each of a pair of imaging optical systems; and a first calculation device that acquires, from the imaging result from the first imaging unit, first information including the size of the object, the position thereof, the time at which the object was imaged, and the position of the first imaging unit when the object was imaged, and transmits the first information to the server. The second imaging device comprises: a second imaging unit that images, by each of a pair of imaging elements, a subject image of the same subject for which an image was formed by each of the pair of imaging optical systems; and a second computation device that acquires second information from the imaging result from the second imaging unit, receives the first information stored in a storage unit from the server, compares the first information with the second information, and performs optical axis correction control of the second imaging unit on the basis of the comparison results.

Description

Technical Field

[0001] The present invention relates to a correction system.

Background Art

[0002] A stereo camera that measures the distance to a subject using two cameras is known. For the ranging accuracy by the stereo camera, it is important that the positions of the optical axes of the two cameras have a known relationship. Patent Document 1 describes a calibration device for an in-vehicle camera that calculates camera parameters indicating the positional relationship of the optical axes of two cameras from feature amounts of road markings formed by white lines or the like, and performs optical axis correction control of the two cameras.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In an environment where it is difficult to generate a parallax peak or a situation where there is no white line, there is a problem that sufficient optical axis correction control cannot be performed by the technique described in Patent Document 1.

[0005] An object of the present invention is to perform appropriate optical axis correction control even in an environment where it is difficult to generate a parallax peak or a situation where there is no white line.

Means for Solving the Problems

[0006] A correction system according to one aspect of the present invention is a correction system having a first imaging device, a second imaging device, and a server, wherein the first imaging device includes a first imaging unit that images an object image of the same object formed by a pair of imaging optical systems using a pair of image sensors, and a first computing unit that acquires first information from the imaging result of the first imaging unit, including the size of the object, the position of the object, the time the object was imaged, and the position of the first imaging unit when the object was imaged, and transmits the first information to the server, the server includes a storage unit that stores the first information transmitted by the first computing unit, and the second imaging device includes a second imaging unit that images an object image of the same subject formed by a pair of imaging optical systems using a pair of image sensors, and a second computing unit that acquires second information from the imaging result of the second imaging unit, receives the first information stored in the storage unit from the server, compares the first information and the second information, and performs optical axis correction control of the second imaging unit based on the comparison result. [Effects of the Invention]

[0007] According to the present invention, appropriate optical axis correction control can be performed even in environments where parallax peaks are unlikely to occur or in situations where there are no white lines. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing the overall configuration of the correction system according to the first embodiment. [Figure 2] Figure 2 is a schematic diagram showing the hardware configuration of the master camera. [Figure 3] Figure 3 is a schematic diagram showing the server's hardware configuration. [Figure 4] Figure 4 is a schematic diagram showing the camera's hardware configuration. [Figure 5] Figure 5 is a schematic diagram showing the functional configuration of the correction system according to the first embodiment. [Figure 6] Figure 6 is a flowchart showing an example of the optical axis correction process performed by the correction system according to the first embodiment. [Figure 7] Figure 7 is a flowchart showing an example of the optical axis correction process performed by the correction system according to the second embodiment. [Modes for carrying out the invention]

[0009] <First Embodiment> A correction system according to an embodiment of the present invention will be described with reference to Figures 1 to 6.

[0010] Figure 1 is a schematic diagram showing the overall configuration of the correction system according to the first embodiment. The correction system 1 of this embodiment includes a server 2, a master vehicle 3, and subordinate vehicles 4. Although only one subordinate vehicle 4 is shown in Figure 1, the correction system 1 may actually include multiple subordinate vehicles 4. Similarly, the correction system 1 may include multiple master vehicles 3.

[0011] The master vehicle 3 is equipped with a master camera 6, a communication device 7, and a position detection device 10. The subordinate vehicle 4 is equipped with a camera 8, a communication device 9, and a position detection device 11. The server 2, master camera 6, and camera 8 are configured to enable data communication via a wireless communication network 5. The wireless communication network 5 is a network such as a mobile phone network.

[0012] Figure 2 is a schematic diagram showing the hardware configuration of the master camera 6. The master camera 6 is a so-called stereo camera. The master camera 6 consists of an imaging unit 25, a computing unit 21, a non-volatile memory 22, a volatile memory 23, an input / output interface 24, and a computer equipped with other peripheral circuits. These hardware components work together to operate the software and realize multiple functions. The master camera 6 may be composed of one computer or multiple computers.

[0013] The imaging unit 25 has a pair of imaging optical systems 26 and a pair of image sensors 27. One image sensor 27 captures the image of a subject formed on the imaging surface by the other imaging optical system 26 and outputs an imaging signal. Similarly, the other image sensor 27 captures the image of a subject formed on the imaging surface by the other imaging optical system 26 and outputs an imaging signal. The pair of imaging optical systems 26 are aligned during the manufacture of the master camera 6, when mounted on the master vehicle 3, and when the master vehicle 3 starts running, etc., so that their optical axis positions are exactly the same in the vertical direction and separated by a certain distance in the horizontal direction. Generally, this distance of the optical axis positions in the horizontal direction is called the baseline length.

[0014] The arithmetic unit 21 is, for example, a CPU (Central Processing Unit), an MPU (Micro Processing Unit), or a DSP (Digital Signal Processor). Alternatively, an ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array) can also be used as the arithmetic unit 21. The non-volatile memory 22 is a storage device such as ROM (Read Only Memory), flash memory, or a hard disk drive. The volatile memory 23 is a storage device known as RAM (Random Access Memory).

[0015] The non-volatile memory 22 stores a program capable of performing various calculations. In other words, the non-volatile memory 22 is a storage medium (memory device) from which the program realizing the functions of this embodiment can be read. The non-volatile memory 22 also stores the camera parameters of the imaging unit 25. The camera parameters include, for example, numerical values ​​representing the positional relationship of the optical axes of the pair of imaging optical systems 26. The volatile memory 23 is a storage medium (memory device) that temporarily stores the calculation results from the arithmetic unit 21 and signals input from the input / output interface 24. The arithmetic unit 21 is a device that expands the program stored in the non-volatile memory 22 into the volatile memory 23 and performs calculations, and performs predetermined calculation processing on data taken from the input / output interface 24, the non-volatile memory 22 and the volatile memory 23 according to the program.

[0016] The master camera 6 is connected to the communication device 7 and the position detection device 10. The input section of the input / output interface 24 converts signals input from various devices (communication device 7, position detection device 10, etc.) into data that can be processed by the arithmetic unit 21. The output section of the input / output interface 24 generates an output signal according to the calculation result of the arithmetic unit 21 and outputs that signal to the various devices (communication device 7, etc.). The communication device 7 performs wireless communication using an antenna (not shown) and communicates data with other devices connected to the wireless communication network 5. The position detection device 10 detects the current position of the master camera 6 using a so-called GNSS (Global Navigation Satellite System). For example, the position detection device 10 receives positioning signals transmitted from multiple artificial satellites and calculates absolute coordinates (hereinafter simply referred to as coordinates) in a specific geodetic system.

[0017] FIG. 3 is a schematic diagram showing the hardware configuration of server 2. Server 2 is composed of a computer including an arithmetic unit 31, a non-volatile memory 32, a volatile memory 33, an input / output interface 34, a master database 35, a communication device 36, and other peripheral circuits. These hardware components cooperate to operate software and realize a plurality of functions. Server 2 may be composed of one computer or a plurality of computers. Regarding each of the arithmetic unit 31, the non-volatile memory 32, the volatile memory 33, and the communication device 36, the description is omitted because it is the same as the content described in the description of the master camera 6.

[0018] The master database 35 is a storage device such as a flash memory or a hard disk drive. A large number of object information (described later) transmitted from the master camera 6 are stored in the master database 35.

[0019] FIG. 4 is a schematic diagram showing the hardware configuration of camera 8. Camera 8 is a so-called stereo camera. Camera 8 is composed of a computer including an imaging unit 45, an arithmetic unit 41, a non-volatile memory 42, a volatile memory 43, an input / output interface 44, and other peripheral circuits. These hardware components cooperate to operate software and realize a plurality of functions. Camera 8 may be composed of one computer or a plurality of computers. Camera 8 is connected to a communication device 9 and a position detection device 11. Regarding each of the arithmetic unit 41, the non-volatile memory 42, the volatile memory 43, the communication device 9, and the position detection device 11, the description is omitted because it is the same as the content described in the description of the master camera 6.

[0020] The imaging unit 45 includes a pair of imaging optical systems 46 and a pair of imaging elements 47. One of the imaging elements 47 captures the subject image formed on the imaging surface by one of the imaging optical systems 46 and outputs an imaging signal. Similarly, the other imaging element 47 captures the subject image formed on the imaging surface by the other imaging optical system 46 and outputs an imaging signal. The pair of imaging optical systems 46 are aligned during the manufacture of the camera 8, when mounted on the vehicle 4, etc., so that their optical axis positions are the same in the vertical direction and are separated by a specific distance in the horizontal direction. The camera parameters of the imaging unit 45 are also stored in the non-volatile memory 42 of the camera 8, similar to the non-volatile memory 22 of the master camera 6. The camera parameters include, for example, numerical values representing the positional relationship of the optical axes of the pair of imaging optical systems 46. The camera parameters stored in the non-volatile memory 42 of the camera 8 are updated by the optical axis correction control described later.

[0021] FIG. 5 is a schematic diagram showing the functional configuration of the correction system according to the first embodiment. The master camera 6 includes an information acquisition unit 51 and a transmission unit 52. The information acquisition unit 51 acquires object information regarding a specific object included in the imaging result from the imaging result by the imaging unit 25. The transmission unit 52 transmits the object information acquired by the information acquisition unit 51 to the server 2. <000,0100><000,0101><000,0102>The server 2 includes a reception unit 53 and a transmission unit 54. The reception unit 53 receives the object information transmitted by the transmission unit 52 of the master camera 6 and stores it in the master database 35. The reception unit 53 also receives the subject information transmitted from the camera 8 and searches the master database 35 for object information regarding the same object as the subject corresponding to the subject information. The transmission unit 54 transmits the search result from the master database 35 to the camera 8. For example, it transmits the object information found in the master database 35 to the camera 8. Or it transmits information indicating that no object information was found in the master database 35 to the camera 8. <000,0103><000,0104><000,0105>Camera 8 comprises an information acquisition unit 55, a transmission unit 56, a reception unit 57, a comparison unit 58, and a correction unit 59. The information acquisition unit 55 acquires subject information relating to a specific subject included in the imaging results from the imaging unit 45. The transmission unit 56 transmits the subject information acquired by the information acquisition unit 55 to the server 2. The reception unit 57 receives the information transmitted from the transmission unit 54 of the server 2. As described above, when the camera 8's transmission unit 56 transmits subject information to the server 2, the server 2's transmission unit 54 sends back to the camera 8 either object information corresponding to the subject information or information indicating that no object information was found. The camera 8's reception unit 57 receives this information returned from the server 2. The comparison unit 58 compares the subject information acquired by the information acquisition unit 55 with the subject information returned from the server 2. The correction unit 59 performs optical axis correction control of the imaging unit 45 based on the comparison result from the comparison unit 58. In this embodiment, the optical axis correction control of the imaging unit 45 refers to a control that suppresses distance measurement errors caused by misalignment of the optical axis of the imaging unit 45 by updating camera parameters stored in the non-volatile memory 42.

[0024] This section explains information gathering by Master Vehicle 3. Master Vehicle 3 is operated by the company or other entity that operates Correction System 1. The operator of Correction System 1 uses Master Vehicle 3 to travel around various locations. During these travels, Master Camera 6 periodically photographs the area around Master Vehicle 3. As a result, objects visible from the Master Vehicle 3's route are photographed by Master Camera 6 as needed. For example, road or road surface installations such as traffic lights, road signs, and road markings are photographed. Similarly, buildings, houses, transmission towers, and other structures (so-called landmarks) are also photographed.

[0025] The information acquisition unit 51 of the master camera 6 measures distance using the imaging results from the imaging unit 25 and measures the distance from the imaging unit 25 to each subject included in the imaging results. The distance to each subject can be represented, for example, by a so-called depth map, which arranges the distance from the imaging unit 25 for each pixel of the image.

[0026] The information acquisition unit 51 of the master camera 6 detects objects from the imaging results of the imaging unit 25 using well-known techniques. For example, techniques such as template matching or object recognition using machine learning can be used. The information acquisition unit 51 acquires object information about the object from the imaging results. The object information includes, for example, a partial image containing the object extracted from the captured image, the size of the object, the position (coordinates) of the object, the date and time the object was photographed, and the position (coordinates) of the imaging unit 25 when the object was photographed. The size of the object can be calculated from the camera parameters of the imaging unit 25 and the distance measurement results. The position of the object can be calculated from the position of the master vehicle 3 detected by the position detection device 10, the installation position of the imaging unit 25 on the master vehicle 3, the orientation (azimuth) of the imaging unit 25 detected by a sensor (not shown), and the distance measurement results.

[0027] The transmitter 52 of the master camera 6 transmits object information acquired by the information acquisition unit 51 to the server 2. When the receiver 53 of the server 2 receives the object information transmitted by the transmitter 52 of the master vehicle 3, it stores it in the master database 35.

[0028] As described above, through the patrol runs of the master vehicle 3, object information corresponding to objects in various locations is accumulated in the master database 35 of the server 2.

[0029] The information acquisition unit 55 of camera 8 detects an object as a subject, similar to the information acquisition unit 51 of master camera 6, from the imaging results of the imaging unit 45 using well-known techniques. The information acquisition unit 55 acquires subject information about that subject from the imaging results. Subject information includes, for example, a partial image containing the subject extracted from the captured image, the size of the subject, the position (coordinates) of the subject, and the position (coordinates) of the imaging unit 45 when the subject was photographed.

[0030] The master camera 6 mounted on the master vehicle 3 is configured to have higher performance and more accurate distance measurement than the camera 8 mounted on the subordinate vehicle 4. For example, the baseline length of the pair of imaging optical systems 26 of the master camera 6 is set to be longer than the baseline length of the pair of imaging optical systems 46 of the camera 8. Generally, increasing the baseline length makes the device larger, but improves distance measurement accuracy. In addition, the imaging unit 25 of the master camera 6 is made of a material with a smaller coefficient of linear expansion than the imaging unit 45 of the camera 8. For example, the housing of the imaging unit 25 of the master camera 6 is made of a material with a smaller coefficient of linear expansion than the housing of the imaging unit 45 of the camera 8. Materials with a smaller coefficient of linear expansion have relatively smaller dimensional changes due to temperature changes, so the influence of temperature changes on the optical axis position can be reduced, improving distance measurement accuracy. However, the selection of materials that make up the imaging unit 25 is limited. In addition, the image sensor 27 of the master camera 6 has a higher number of pixels than the image sensor 47 of the camera 8. A higher pixel count allows for more precise (i.e., higher resolution) distance measurement, but it also increases the size, price, and power consumption of the image sensor.

[0031] Furthermore, the master camera 6 mounted on the master vehicle 3 has its optical axis alignment more precisely than the camera 8 mounted on the subordinate vehicle 4. To enable more accurate distance measurement, the optical axis alignment may be performed after each run, or the optical axis position calibration and camera parameter updates may be performed after each run. In this way, the misalignment of the optical axis in the master camera 6 can be eliminated (or made negligibly small).

[0032] As described above, the distance measurement accuracy of the master camera 6 is extremely high, so the object information acquired by the information acquisition unit 51 of the master camera 6 is extremely accurate. In other words, the object information stored in the master database 35 of the server 2 is extremely accurate.

[0033] Figure 6 is a flowchart showing an example of the optical axis correction process performed by the correction system according to the first embodiment. The optical axis correction process is repeatedly performed by the camera 8's arithmetic unit 41 when the camera 8 is powered on. In step S100, the arithmetic unit 41 causes the position detection device 11 to detect the position (coordinates) of the camera 8. In step S110, the arithmetic unit 41 determines whether the position of the camera 8 detected in step S110 is within a predetermined facility under the management of the operator of the correction system 1, such as a factory or car dealership, and whether the subordinate vehicle 4 is parked. If the camera 8 is within a predetermined facility and the subordinate vehicle 4 is parked, the process proceeds to step S120. On the other hand, if the camera 8 is not within a predetermined facility, or if the subordinate vehicle 4 is not parked, the process proceeds to step S150.

[0034] In step S120, the computing unit 41 instructs the imaging unit 45 to capture an image of a subject. The imaging in step S130 assumes that the subject is, for example, a calibration chart. In step S130, the computing unit 41 obtains subject information from the imaging result in step S120 and receives object information corresponding to that subject information from the server 2. The master database 35 of the server 2 stores object information obtained in advance from imaging calibration charts, etc., within a predetermined facility. In step S140, the computing unit 41 performs optical axis correction control using the subject information obtained in step S130 and the received object information. Specifically, it compares the image of the object included in the object information with the image of the object included in the subject information and calculates the size difference of the image of the object in each image. Then, based on that size difference, it updates the camera parameters stored in the non-volatile memory 42.

[0035] In step S150, the computing unit 41 determines whether the location of the camera 8 detected in step S110 is within a facility of a type predetermined by the operator of the correction system 1, such as a gas station or a multi-story parking garage, and whether the subordinate vehicle 4 is parked. If the camera 8 is located within such a facility and the subordinate vehicle 4 is parked, the process proceeds to step S160. On the other hand, if the camera 8 is not located within such a facility, or if the subordinate vehicle 4 is not parked, the process proceeds to step S200.

[0036] In step S160, the arithmetic unit 41 instructs the imaging unit 45 to capture an image of the subject. In step S170, the arithmetic unit 41 obtains subject information from the imaging result in step S160 and receives object information corresponding to that subject information from the server 2. Note that if the master database 35 of the server 2 does not contain object information corresponding to that subject information, that is, if there is no object information for the same object as the subject that is the subject of the subject information, the arithmetic unit 41 cannot receive object information from the server 2 in step S170 (reception fails). In step S180, the arithmetic unit 41 determines whether or not it was able to receive object information from the server 2 in step S170. If object information was received, that is, if there was object information corresponding to the subject information, the process proceeds to step S190. On the other hand, if object information was not received, that is, if there was no object information corresponding to the subject information, the process proceeds to step S200.

[0037] In step S190, the arithmetic unit 41 performs optical axis correction control using the subject information acquired in step S170 and the received object information. Specifically, it compares the image of the object included in the object information with the image of the object included in the subject information and calculates the size difference of the image of the object in each image. Then, based on that size difference, it updates the camera parameters stored in the non-volatile memory 42.

[0038] In step S200, the computing unit 41 instructs the imaging unit 45 to capture an image of the subject. In step S210, the computing unit 41 obtains subject information from the imaging result in step S200 and receives object information corresponding to that subject information from the server 2. Note that if the master database 35 of the server 2 does not contain object information corresponding to that subject information, that is, if there is no object information for the same object as the subject that is the subject of the subject information, the computing unit 41 cannot receive object information from the server 2 in step S210 (reception fails). In step S220, the computing unit 41 determines whether or not it was able to receive object information from the server 2 in step S210. If object information was received, that is, if there was object information corresponding to the subject information, the process proceeds to step S230. On the other hand, if object information was not received, that is, if there was no object information corresponding to the subject information, the process shown in Figure 6 ends.

[0039] In step S230, the arithmetic unit 41 performs optical axis correction control using the subject information acquired in step S210 and the received object information. Specifically, it calculates the distance to the object using the position of the object included in the object information and the position of the camera 8 detected by the position detection device 11. Then, it compares the calculated distance with the distance to the subject included in the subject information. If there is no misalignment in the optical axis position, these distances should match very well. Conversely, if there is a misalignment in the optical axis position, the discrepancy between these distances will increase due to the misalignment. Based on the difference in these distances, the arithmetic unit 41 updates the camera parameters stored in the non-volatile memory 42 and terminates the process shown in Figure 6.

[0040] According to the first embodiment described above, the following effects are achieved.

[0041] (1) The imaging unit 25 (first imaging unit) of the master camera 6 (first imaging device) captures an image of the same object, which has been imaged by a pair of imaging optical systems 26, using a pair of image sensors 27. The computing unit 21 (first computing unit) of the master camera 6 (first imaging device) acquires object information (first information) from the imaging results of the imaging unit 25 (first imaging unit), including the size of the object, the position of the object, the time the object was imaged, and the position of the imaging unit 25 (first imaging unit) when the object was imaged, and transmits the object information (first information) to the server 2. The server 2 is equipped with a master database 35 (storage unit) that stores the object information (first information) transmitted by the master camera 6 (first imaging device). The imaging unit 45 (second imaging unit) of the camera 8 (second imaging device) captures an image of the same subject, which has been imaged by a pair of imaging optical systems 46, using a pair of image sensors 47. The arithmetic unit 41 (second arithmetic unit) of camera 8 (second imaging device) acquires subject information (second information) from the imaging results of the imaging unit 45 (second imaging unit), receives object information (first information) stored in the master database 35 (storage unit) from server 2, compares the object information (first information) with the subject information (second information), and performs optical axis correction control of the imaging unit 45 (second imaging unit) based on the comparison result. In this way, appropriate optical axis correction control can be performed even in environments where it is difficult to recognize white lines due to the effects of weather, situations where it is difficult to recognize white lines because they are faded or thin, or situations where there are no white lines. Furthermore, by performing optical axis correction appropriately, the distance measurement accuracy is improved, so that devices that use the distance measurement results, such as collision avoidance brakes, can be operated appropriately.

[0042] (2) The baseline length of the imaging unit 25 (first imaging unit) is longer than that of the imaging unit 45 (second imaging unit), the material constituting the housing of the imaging unit 25 (first imaging unit) has a smaller coefficient of thermal expansion than the material constituting the housing of the imaging unit 45 (second imaging unit), and the number of pixels of the pair of image sensors 27 used by the imaging unit 25 (first imaging unit) is greater than the number of pixels of the pair of image sensors 47 used by the imaging unit 45 (second imaging unit). In this way, the object information output by the master camera 6 is based on accurate distance measurement results, enabling highly accurate optical axis correction control.

[0043] (3) Subject information (second information) includes the size of the subject, the position of the subject, and the position of the imaging unit 45 (second imaging unit) when the subject was imaged. By using this method with objects that frequently appear on the driving route, such as traffic lights, road signs, and road markings, it becomes possible to correct the optical axis while driving.

[0044] (4) When the position of the imaging unit 45 (second imaging unit) when capturing an image of a subject is a predetermined position, the arithmetic unit 41 (second arithmetic unit) receives object information (first information) from the server that includes the predetermined position as the position of the imaging unit 25 (first imaging unit), compares the image of the object included in the object information (first information) with the image of the subject included in the subject information (second information), calculates the size difference of the object image in each image, and performs optical axis correction control of the imaging unit 45 (second imaging unit) based on the size difference. By performing optical axis correction control at a predetermined point in this way, it is possible to ensure that object information corresponding to subject information is reliably included in the master database 35, and to perform optical axis correction control with high accuracy.

[0045] (5) Subject information (second information) includes the distance from the imaging unit 45 (second imaging unit) to the subject. Camera 8 (second imaging device) is equipped with a position detection device 11 (positioning device) that measures the position of camera 8 (second imaging device). If the subject imaged by the imaging unit 45 (second imaging unit) is the same as the object imaged by the imaging unit 25 (first imaging unit), the computing unit 41 (second computing unit) calculates the distance to the subject using the position of the object included in the object information (first information) and the measured position, and performs optical axis correction control of the imaging unit 45 (second imaging unit) based on the calculated distance and the distance included in the subject information (second information). In this way, appropriate optical axis correction control can be performed.

[0046] <Second Embodiment> Referring to Figure 7, a correction system according to the second embodiment of the present invention will be described. Note that the same or equivalent components as those described in the first embodiment will be denoted by the same reference numerals, and the differences will be primarily explained.

[0047] Figure 7 is similar to Figure 6 and is a flowchart showing an example of the optical axis correction process performed by the correction system according to the second embodiment. In the flowchart of Figure 7, the process in step S330 is performed instead of the process in step S230 of the flowchart of Figure 6.

[0048] In step S330, the arithmetic unit 41 performs coordinate correction control using the subject information acquired in step S210 and the received object information. Coordinate correction control is a control that corrects the position (coordinates) of the camera 8 detected by the position detection device 11. Specifically, the current position of the camera 8 (position at the time of imaging) is calculated using the position of the object included in the object information and the distance from the camera 8 to the object included in the subject information. Then, the position of the camera 8 detected by the position detection device 11 is corrected using the calculated position. In other words, here, assuming that there is no positional shift in the optical axis position, the positional shift detected by the position detection device 11 is corrected.

[0049] According to the second embodiment described above, the following effects are achieved.

[0050] (1) Subject information (second information) includes the distance from the imaging unit 45 (second imaging unit) to the subject. Camera 8 (second imaging device) is equipped with a position detection device 11 (positioning device) that measures the position of camera 8 (second imaging device). If the subject imaged by the imaging unit 45 (second imaging unit) is the same as the object imaged by the imaging unit 25 (first imaging unit), the calculation unit 41 (second calculation unit) calculates the position of camera 8 (second imaging device) using the position of the object included in the object information (first information) and the distance to the subject included in the subject information (second information), and corrects the measured position using the calculated position. In this way, not only optical axis correction but also positioning position correction can be performed simultaneously.

[0051] The following modifications are also within the scope of the present invention, and it is possible to combine the configurations shown in the modifications with the configurations described in the embodiments described above, or to combine the configurations described in the different embodiments described above, or to combine the configurations described in the following different modifications.

[0052] <Example 1> The camera 8 or a device mounted on the subordinate vehicle 4 may be pre-stored with high-precision map information. In this case, the location of an object retrieved from the high-precision map information can be used instead of the location of the object included in the object information.

[0053] <Modification 2> During operation, the series of processes for correcting the coordinates described in the second embodiment (steps S200 to S330 in Figure 7) and the series of processes for correcting the optical axis described in the first embodiment (steps S200 to S230 in Figure 6) may be repeatedly and alternately executed. This allows for proper maintenance of the accuracy of the optical axis.

[0054] Although embodiments of the present invention have been described above, these embodiments only represent a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. [Explanation of symbols]

[0055] 1...Correction system, 2...Server, 3...Master vehicle, 4...Subordinate vehicles, 5...Wireless communication network, 6...Master camera (first imaging device), 7, 9, 36...Communication device, 8...Camera (second imaging device), 10, 11...Position detection device (positioning device), 21, 31, 41...Computation unit (first computing unit, second computing unit), 22, 32, 42...Non-volatile memory, 23, 33, 43...Volatile memory, 24, 34, 44...Input / output interface, 25, 45...Imaging unit (first imaging unit, second imaging unit), 26, 46...Imaging optical system, 27, 47...Image sensor, 35...Master database (storage unit), 51, 55...Information acquisition unit, 52, 54, 56...Transmission unit, 53, 57...Receiving unit, 58...Comparison unit, 59...Correction unit

Claims

1. A correction system comprising a first imaging device, a second imaging device, and a server, The first imaging device is A first imaging unit captures object images of the same object, each image formed by a pair of imaging optical systems, using a pair of image sensors. The system includes a first computing device that acquires first information from the imaging results of the first imaging unit, including the size of the object, the position of the object, the time the object was imaged, and the position of the first imaging unit when the object was imaged, and transmits the first information to the server. The aforementioned server, The system includes a storage unit that stores the first information transmitted by the first computing unit, The second imaging device described above is A second imaging unit captures subject images of the same subject, each image formed by a pair of imaging optical systems, using a pair of image sensors. The system includes a second computing device that acquires second information from the imaging results of the second imaging unit, receives the first information stored in the storage unit from the server, compares the first information with the second information, and performs optical axis correction control of the second imaging unit based on the comparison result. Correction system.

2. In the correction system described in claim 1, The baseline length of the first imaging unit is longer than the baseline length of the second imaging unit. The material constituting the housing of the first imaging unit has a smaller coefficient of thermal expansion than the material constituting the housing of the second imaging unit. A correction system in which the number of pixels of the pair of image sensors used by the first imaging unit is greater than the number of pixels of the pair of image sensors used by the second imaging unit.

3. In the correction system described in claim 1, The correction system includes, as the second information, the size of the subject, the position of the subject, and the position of the second imaging unit when the subject is imaged.

4. In the correction system described in claim 1, The second computing unit, when the position of the second imaging unit when the subject image is captured is a predetermined position, receives first information from the server which includes the predetermined position as the position of the first imaging unit, compares the image of the object included in the first information with the image of the subject included in the second information to calculate the size difference of the image of the object in each image, and performs optical axis correction control of the second imaging unit based on the size difference, thereby providing a correction system.

5. In the correction system described in claim 1, The second information includes the distance from the second imaging unit to the subject, The second imaging device further comprises a positioning device for determining the position of the second imaging device, The second computing device, when the subject is an object, calculates the position of the second imaging device using the position of the object included in the first information and the distance to the subject included in the second information, and corrects the positioned position using the calculated position, is a correction system.

6. In the correction system described in claim 1, The second information includes the distance from the second imaging unit to the subject, The second imaging device further comprises a positioning device for determining the position of the second imaging device, The second computing unit, when the subject is an object, calculates the distance to the subject using the position of the object included in the first information and the measured position, and performs optical axis correction control of the second imaging unit based on the calculated distance and the distance included in the second information, as a correction system.

Images