Monitor system and monitor method

Abstract

To provide information to a user at desired timing, while improving detection accuracy.SOLUTION: A monitor system 1 includes a detection device 8 for detecting an object existing in a monitor region Rd. The detection device 8 includes: a wireless input part 80 for acquiring partial information Dp1 via wireless communication; an acquisition part 81 for acquiring partial information Dp2 via cable communication; and a detection processing part 86 for generating the detection result Dd regarding the object existing in the monitor region Rd, on the basis of the partial information Dp1 and the partial information Dp2. The detection processing part 86 starts generating the detection result Dd based on the partial information Dp1 and the partial information Dp2, at earlier one of the timing when the detection device 8 acquires the partial information Dp1 for one frame via the wireless communication and the timing when certain time has elapsed from reference time.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a monitoring system and a monitoring method. [Background technology]

[0002] In order to support vehicle driving and pedestrian safety, traffic information monitoring systems have been developed that collect information on vehicles, pedestrians, etc. in monitored areas such as intersections and provide the information to users. For example, Patent Document 1 discloses a laser radar that scans an intersection with a laser beam to obtain information on a plurality of measurement points and detects vehicles present in the intersection based on the information on the plurality of measurement points. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-197341 A Summary of the Invention [Problem to be solved by the invention]

[0004] Laser radars cannot irradiate laser light into areas (blind spots) that are shaded by obstructing objects, and so there is a risk that they will be unable to detect objects in such areas. For example, when a large truck or the like crosses an intersection, it may not be possible to detect bikes and pedestrians that are in the shadow of the truck. This phenomenon is called occlusion. To address this problem and improve detection accuracy, multiple laser radars may be installed. In this case, measurement point information acquired by each laser radar is transmitted to a detection device that is communicatively connected to each laser radar, and object detection is performed by the detection device based on each measurement point information.

[0005] However, depending on the communication conditions of each radar laser, a delay may occur in communication between any of the laser radars and the detection device. In such a case, the generation of the detection result by the detection device may be delayed according to the communication delay, and the provision of the detection result to the user may also be delayed. Therefore, in such a monitoring system, it may be difficult to provide information at the timing desired by the user.

[0006] The present disclosure describes a monitoring system and a monitoring method that can provide information to a user at a desired timing while improving detection accuracy. [Means for solving the problem]

[0007] A monitoring system according to one aspect of the present disclosure monitors a monitoring area using a first laser sensor and a second laser sensor, each of which is installed on the ground and which irradiates laser light toward an irradiable area including at least a portion of the monitoring area and generates measurement point information including position coordinates of each measurement point within the irradiable area by receiving reflected light of the laser light, and is equipped with a detection device that detects objects present in the monitoring area, and the detection device includes a wireless input unit that acquires first point cloud information including a plurality of measurement point information generated by the first laser sensor via wireless communication, a wired input unit that acquires second point cloud information including a plurality of measurement point information generated by the second laser sensor via wired communication, and a detection processing unit that generates detection results regarding objects present in the monitoring area based on the first point cloud information and the second point cloud information, and the detection processing unit starts generating detection results based on the first point cloud information and the second point cloud information at the earlier of the timing when the detection device acquires one frame's worth of first point cloud information via wireless communication and the timing when a certain amount of time has elapsed from a reference time.

[0008] In the above monitoring system, the monitoring area is monitored using a first laser sensor and a second laser sensor installed on the ground. This reduces blind spots in the monitoring area, thereby improving detection accuracy. Furthermore, in the above monitoring system, a detection device that detects an object present in the monitoring area acquires first point cloud information via wireless communication, while acquiring second point cloud information via wired communication. In this case, the timing at which the detection device acquires the first point cloud information via wireless communication tends to be delayed with respect to the timing at which the detection device acquires the second point cloud information via wired communication. In this case, from the viewpoint of improving detection accuracy, if the detection device starts generating a detection result at the timing at which both one frame of first point cloud information and one frame of second point cloud information are available, it is assumed that the generation of the detection result will also be delayed according to the delay in the timing at which the detection device acquires one frame of first point cloud information. In contrast, in the above monitoring system, the generation of the detection result based on the first point cloud information and the second point cloud information is started at the earlier of the timing at which the detection device acquires one frame of first point cloud information via wireless communication and the timing at which a certain time has elapsed from the reference time. In this case, even if there is a delay in the timing at which the detection device acquires one frame of the first point cloud information, the detection result can be generated at a timing when a certain time has elapsed from the reference time. As a result, it is possible to provide the detection result to the user at any timing desired by the user, without waiting for the timing at which the detection device acquires one frame of the first point cloud information. Therefore, according to the above monitoring system, it is possible to provide information to the user at a desired timing while improving the detection accuracy.

[0009] In some embodiments, the detection processing unit may repeatedly generate the detection result each time the earlier timing occurs, and the reference time may be the time when the previous earlier timing occurs. In this case, it is easy to adjust the timing for starting generation of the detection result, and it is therefore easy to provide the detection result to the user at a desired timing.

[0010] In some embodiments, the detection processing unit may stop the process of generating the detection result when an event occurs M times (M: an integer equal to or greater than 1) in which the timing when a certain time has elapsed from the reference time arrives earlier than the timing when the detection device acquires one frame of the second point cloud information via wired communication. In this case, it is possible to prevent a detection result with low detection accuracy from being provided to a user.

[0011] In some embodiments, the monitoring system further includes a processing device that is wirelessly connected to the wireless input unit, processes the first point cloud information acquired from the first laser sensor, and transmits the processed first point cloud information to the wireless input unit, and the processing device includes a processing device that performs a first process of deleting excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the first point cloud information, and the detection processing device may generate a detection result based on the first point cloud information processed by the processing device and the second point cloud information in which the process of deleting excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the second point cloud information has not been performed. In this way, when the first process of deleting excluded measurement point information is performed on the first point cloud information acquired by the detection device via wireless communication that is prone to delays, the data amount of the first point cloud information processed by the processing device is smaller than the data amount of the first point cloud information before the process. In this case, the time required to transmit the first point cloud information from the processing device to the detection device via wireless communication can be shortened compared to the case where the first point cloud information is transmitted as is from the processing device to the detection device via wireless communication. This makes it possible to prevent a situation in which the timing at which the detection device acquires the first point cloud information via wireless communication is significantly delayed from the timing at which the detection device acquires the second point cloud information via wired communication. On the other hand, since the second point cloud information is transmitted from the processing device to the detection device via wired communication, there is little concern that a delay will occur in the timing at which the detection device acquires the second point cloud information even if the second point cloud information is transmitted directly to the detection device. Therefore, in the above configuration, the processing device for performing the above-mentioned processing on the second point cloud information is omitted, thereby simplifying the overall configuration of the monitoring system.

[0012] In some embodiments, the monitoring system further includes a processing device that is wirelessly connected to the wireless input unit, processes the first point cloud information acquired from the first laser sensor, and transmits the processed first point cloud information to the wireless input unit, the processing device includes a processing unit that performs a first process of deleting from the first point cloud information first excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range, the detection device further includes a point cloud processing unit that performs a first process of deleting from the second point cloud information second excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range, and the detection processing unit may generate a detection result based on the first point cloud information after processing by the processing unit and the second point cloud information after processing by the point cloud processing unit. In this case, the data amount of the first point cloud information after processing by the processing unit is smaller than the data amount of the first point cloud information before processing. Similarly, the data amount of the second point cloud information after processing by the point cloud processing unit is smaller than the data amount of the second point cloud information before processing. As a result, the detection processing unit can generate a detection result based on the first point cloud information and the second point cloud information with small data amounts. This reduces the processing load when the detection processing unit generates a detection result. Furthermore, in the above configuration, since the detection device includes a point cloud processing unit that processes the second point cloud information, there is no need to install a separate processing device that includes a function equivalent to the point cloud processing unit between the detection device and the second laser sensor. Therefore, in the above configuration, since the processing device can be omitted in this way, the overall configuration of the monitoring system is simplified.

[0013] In some embodiments, the point cloud processor may further perform a second process of dividing the monitoring area into a plurality of areas, and deleting target measurement point information including at least one measurement point in the area from the second point cloud information when the density of the measurement points included in the area is higher than a threshold value. In this case, the data amount of the second point cloud information after processing by the point cloud processor becomes even smaller than the data amount of the second point cloud information before processing. This can further reduce the processing load when the detection processor generates the detection result.

[0014] In some embodiments, the processing unit may further perform a second process of dividing the monitoring area into a plurality of areas, and deleting target measurement point information including at least one measurement point in the area from the first point cloud information when the density of the measurement points included in the area is higher than a threshold value. In this case, the data amount of the first point cloud information after the process is further smaller than the data amount of the first point cloud information before the process. In this case, the time required to transmit the first point cloud information from the processing device to the detection device can be further shortened. This makes it possible to more effectively suppress delays in wireless communication between the processing device and the detection device. As a result, it is possible to more effectively suppress a situation in which the timing at which the detection device acquires the first point cloud information via wireless communication is significantly delayed with respect to the timing at which the detection device acquires the second point cloud information via wired communication.

[0015] A monitoring method according to an aspect of the present disclosure is a monitoring method implemented by a monitoring system that monitors a monitoring area using a first laser sensor and a second laser sensor that are installed on the ground and generate measurement point information including position coordinates of each measurement point in the irradiable area by irradiating a laser beam toward an irradiable area including at least a part of the monitoring area and receiving a reflected light of the laser beam, the monitoring method comprising the steps of: acquiring first point cloud information including a plurality of measurement point information generated by the first laser sensor via wireless communication; acquiring second point cloud information including a plurality of measurement point information generated by the second laser sensor via wired communication; and generating a detection result regarding an object present in the monitoring area based on the first point cloud information and the second point cloud information, wherein in the step of generating the detection result, generation of the detection result based on the first point cloud information and the second point cloud information is started at the timing when the detection device acquires one frame of the first point cloud information via wireless communication, or at the timing when a certain time has elapsed from a reference time, whichever is earlier. According to this monitoring method, as described above, it is possible to provide information to a user at a desired timing while improving the detection accuracy. Effect of the Invention

[0016] According to the present disclosure, it is possible to provide information to a user at a desired timing while improving detection accuracy. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of a monitoring system according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of the arrangement of the master laser radar device and the slave laser radar device shown in FIG. [Diagram 3] FIG. 3 is a perspective view showing the arrangement example of FIG. [Figure 4] FIG. 4 is a diagram illustrating an example of point cloud information. [Diagram 5] FIG. 5 is a diagram illustrating a hardware configuration of the processing device illustrated in FIG. [Figure 6] FIG. 6 is a flowchart showing the partial information generation process performed by the slave laser radar device. [Figure 7] FIG. 7 is a flowchart showing the partial information generation process performed by the master laser radar device. [Figure 8] FIG. 8 is a flowchart showing the detection process performed by the master laser radar device. [Figure 9] FIG. 9 is a diagram illustrating a schematic configuration of a monitoring system according to the first modification. [Figure 10] FIG. 10 is a diagram illustrating a schematic configuration of a monitoring system according to the second modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated description will be omitted.

[0019] The monitoring system 1 shown in FIG. 1 monitors a monitoring area Rd using laser sensors 4 and 6 described below. The monitoring system 1 detects, for example, an object (moving body) present in the monitoring area Rd shown in FIG. 2. The monitoring area Rd is an area to be monitored by the monitoring system 1. The monitoring area Rd can be set at any location on a road. For example, an intersection, a junction, or a middle of a road is selected as a setting location for the monitoring area Rd. As shown in FIG. 2 and FIG. 3, in this embodiment, the monitoring area Rd is set at an intersection C. Examples of objects to be monitored include vehicles and pedestrians (people).

[0020] The monitoring system 1 includes, for example, a slave laser radar device 2 and a master laser radar device 3. The slave laser radar device 2 and the master laser radar device 3 are installed, for example, near the monitoring area Rd. In this embodiment, the slave laser radar device 2 and the master laser radar device 3 are installed on a diagonal line of an intersection C. The intersection C is a point where four roads Tr1 to Tr4 join together. The roads Tr1 and Tr2 extend in one direction and are connected to each other via the intersection C. The roads Tr3 and Tr4 extend in a direction intersecting the roads Tr1 and Tr2 and are connected to each other via the intersection C. The slave laser radar device 2 and the master laser radar device 3 are fixed to a support member P (see FIG. 3) installed on the ground. The support member P is, for example, a columnar structure installed on the roadside near the intersection C. The support member P may be a utility pole, a wall of a warehouse, or the like.

[0021] 1, the slave laser radar device 2 and the master laser radar device 3 are communicatively connected to each other via a communication line N. The communication line N may be a non-dedicated line such as an Internet line or a mobile communication network, or may be a dedicated line. At an intersection C or the like, the distance between the slave laser radar device 2 and the master laser radar device 3 is long, so it may be difficult to wire a dedicated line as the communication line N. For this reason, in this embodiment, a wireless communication line is used as the communication line N.

[0022] The slave laser radar device 2 includes, for example, a laser sensor 4 (first laser sensor), a processing device 5, and a wireless output unit 50. The laser sensor 4 is fixed to, for example, a support member P. In this case, the laser sensor 4 is installed on the ground. The laser sensor 4 irradiates a laser beam toward an irradiable area Ra (see FIG. 2) and receives reflected light of the irradiated laser beam to generate measurement point information of each measurement point within the irradiable area Ra. The irradiable area Ra is an area in which the laser sensor 4 can irradiate a laser beam, and is, for example, a range of about 150 m. The irradiable area Ra includes at least a part of the monitoring area Rd.

[0023] As shown in FIG. 4, the measurement point information includes time information and position information. The time information is information indicating the time when the measurement point information of the measurement point indicated by the position information was generated (when the reflected light was received). The position information is information indicating the position coordinates of the measurement point. For the position coordinates, a polar coordinate system represented by a yaw angle, a pitch angle, and a depth may be used, or a three-dimensional coordinate system represented by an x ​​coordinate, a y coordinate, and a z coordinate may be used. The coordinate system CS used in this embodiment is a three-dimensional coordinate system. The x axis of the coordinate system CS extends along the roads Tr1 and Tr2, and is set so that the direction from the road Tr1 to the road Tr2 is positive. The y coordinate of the coordinate system CS extends along the roads Tr3 and Tr4, and is set so that the direction from the road Tr3 to the road Tr4 is positive. The z axis of the coordinate system CS is set so that the ground surface is used as a reference (z=0) and the direction above the ground surface is positive. The measurement point information may further include reflection intensity information. The reflection intensity information is information that indicates the intensity of reflected light received from a measurement point indicated by the position information at a time indicated by the time information.

[0024] The laser sensor 4 scans the irradiatable area Ra in the main scanning direction and the sub-scanning direction by changing the irradiation direction of the laser light. As a result, the laser light is sequentially irradiated to a plurality of measurement points included in the irradiatable area Ra. A round of irradiation of the laser light to all measurement points included in the irradiatable area Ra may be called one frame. The irradiation of the laser light to the irradiatable area Ra is repeated at regular time intervals.

[0025] The laser sensor 4 outputs point cloud information Dm1 (first point cloud information) including information on a plurality of measurement points to the processing device 5 at a predetermined period. The laser sensor 4 outputs the point cloud information Dm1 to the processing device 5 for each of a plurality of packets included in one frame, for example. Therefore, the period in which the laser sensor 4 outputs the point cloud information Dm1 to the processing device 5 matches the period in which the laser sensor 4 acquires one packet of point cloud information Dm1. The laser sensor 4 outputs the point cloud information Dm1 to the processing device 5 in, for example, a table format shown in FIG.

[0026] The processing device 5 processes point cloud information Dm1 including information on a plurality of measurement points generated by the laser sensor 4. The processing device 5 is constituted by, for example, an information processing device such as a computer.

[0027] As shown in Fig. 5, the processing device 5 may be physically configured as a computer including hardware such as one or more processors 101, a main storage device 102 such as a RAM (Random Access Memory) and a ROM (Read Only Memory), an auxiliary storage device 103 such as a hard disk device, and a communication device 104 which is a data transmission / reception device. Each functional unit of the processing device 5 shown in Fig. 1 is realized by executing a program module for realizing each function in the computer constituting the processing device 5. A program including these program modules is provided by a computer-readable recording medium such as a ROM or a semiconductor memory. The program may also be provided as a data signal via a network.

[0028] The processing device 5 includes, as its functional components, an acquisition unit 51, a storage unit 52, and a processing unit 53, for example.

[0029] The acquisition unit 51 acquires the point cloud information Dm1 for each packet from the laser sensor 4. The acquisition unit 51 adds a timestamp indicating the time when the point cloud information Dm1 was acquired to the point cloud information Dm1. The acquisition unit 51 outputs the point cloud information Dm1 with the timestamp added to the processing unit 53.

[0030] The memory unit 52 stores various setting information. The various setting information includes exclusion information indicating a detection exclusion range. The detection exclusion range is a range that is not monitored. The detection exclusion range includes a range outside the monitoring area Rd and a range of the monitoring area Rd that does not need to be monitored. The detection exclusion range is set in advance. For example, the user sets the detection exclusion range using an input device. For example, a three-dimensional space simulating an intersection C is displayed on an output device such as a display, and the user sets the detection exclusion range using a frame or the like.

[0031] For example, the area below the ground level and the air above the road may not be monitored. Therefore, in order to exclude the area below the ground level, a range lower than a predetermined height based on the ground surface may be set as the height of the detection exclusion range. For example, a range of z<20 cm is set as the detection exclusion range. In order to exclude the air above, a range higher than a predetermined height based on the ground surface may be set as the height of the detection exclusion range. For example, a range of z>500 cm is set as the detection exclusion range. In addition, there are fixed objects (stationary objects) such as traffic lights, poles, utility poles, roadside trees, and elevated roads in and around the intersection C. Since these fixed objects do not need to be monitored, a range of fixed objects may be set as the detection exclusion range in order to exclude these fixed objects. The range of fixed objects may be set as coordinates (x, y) indicating the boundaries of the fixed objects in the xy plane.

[0032] The processing unit 53 processes the point cloud information Dm1. Specifically, when the processing unit 53 receives the point cloud information Dm1 from the acquisition unit 51, the processing unit 53 performs a first process and a second process on the point cloud information Dm1. In the first process, the processing unit 53 excludes (deletes) excluded measurement point information of measurement points included in the detection exclusion range indicated by the exclusion information read from the storage unit 52 from the point cloud information Dm1. In other words, the first process is an exclusion process that excludes unnecessary excluded measurement point information from the point cloud information Dm1. As a result, measurement points that are not monitored are excluded from the point cloud information Dm1, and abnormal measurement point information caused by noise or the like is excluded.

[0033] In the second process, the processing unit 53 divides the monitoring area Rd into a plurality of areas, and when the density of the measurement points included in the area is higher than a threshold, deletes the target measurement point information including at least one measurement point in the area from the second point cloud information. That is, the second process is a thinning process that thins out the measurement points included in an area of ​​the monitoring area Rd with a high density of measurement points. For example, when the density of the measurement points in the area is higher than a threshold, the processing unit 53 may exclude the measurement points included in the area so that the density of the measurement points is equal to or lower than the threshold. As a result, the measurement points to be thinned out are excluded from the point cloud information Dm1. That is, the measurement point information of the measurement points to be thinned out is excluded from the point cloud information Dm1.

[0034] The processing unit 53 removes unnecessary measurement point information from the point cloud information Dm1 through the first process and the second process, and generates partial information Dp1 including the remaining measurement point information. The partial information Dp1 is the point cloud information Dm1 after processing by the processing unit 53. By removing unnecessary measurement point information from the point cloud information Dm1, the data amount of the partial information Dp1 becomes smaller than the data amount of the point cloud information Dm1. The processing unit 53 outputs the generated point cloud information Dm1 to the wireless output unit 50.

[0035] The processing unit 53 may perform the first process and the second process on the point cloud information Dm1 in order, or may perform the first process and the second process on the point cloud information Dm1 simultaneously. The processing unit 53 does not necessarily have to perform both the first process and the second process on the point cloud information Dm1, and may perform only one of the first process and the second process on the point cloud information Dm1. In this embodiment, the processing by the processing unit 53 means both the first process and the second process. The processing unit 53 may perform other processes on the point cloud information Dm1 in addition to the first process and the second process, or instead of the first process and the second process.

[0036] The wireless output unit 50 outputs the partial information Dp1 for each packet to the outside of the slave laser radar device 2. Specifically, when the wireless output unit 50 receives the partial information Dp1 from the processing unit 53, it transmits the partial information Dp1 for each packet at a predetermined period to the master laser radar device 3 via the communication line N (wireless communication).

[0037] The master laser radar device 3 includes, for example, a laser sensor 6, a processing device 7, a detection device 8, and a wireless input unit 80. The laser sensor 6 is fixed to a support member P. That is, the laser sensor 6 is installed on the ground. Like the laser sensor 4, the laser sensor 6 irradiates a laser beam toward the irradiable area Rb and receives reflected light of the irradiated laser beam to generate measurement point information of each measurement point within the irradiable area Rb. The irradiable area Rb is an area where the laser sensor 6 can irradiate a laser beam, and is, for example, a range of about 150 m. The irradiable area Rb includes at least a part of the monitoring area Rd. The same coordinate system CS as that of the laser sensor 4 is used in the laser sensor 6.

[0038] The laser sensor 6 outputs point cloud information Dm2 (second point cloud information) including information on multiple measurement points to the processing device 7 at a predetermined period. The laser sensor 6 outputs the point cloud information Dm2 to the processing device 7 for each of multiple packets included in one frame. Therefore, the period in which the laser sensor 6 outputs the point cloud information Dm2 to the processing device 7 matches the period in which the laser sensor 6 acquires one packet of point cloud information Dm2. The period in which the laser sensor 6 outputs the point cloud information Dm2 to the processing device 7 matches the period in which the laser sensor 4 outputs the point cloud information Dm1 to the processing device 5.

[0039] The time of the laser sensor 6 is synchronized with the time of the laser sensor 4. The time of the laser sensor 4 and the time of the laser sensor 6 are synchronized, for example, by using NTP (Network Time Protocol). For example, when the laser sensor 6 acquires one frame of point cloud information Dm2, it outputs a one-frame completion flag indicating that acquisition of one frame of point cloud information Dm2 has been completed to the processing device 7.

[0040] The processing device 7 is a device that generates partial information Dp2 by processing point cloud information Dm2 including a plurality of measurement point information generated by the laser sensor 6. The processing device 7 is configured by, for example, an information processing device such as a computer. The physical configuration of the processing device 7 is similar to the physical configuration of the processing device 5. Each functional unit of the processing device 7 shown in FIG. 1 is realized by executing a program module for realizing each function in the computer constituting the processing device 7. A program including these program modules is provided by, for example, a computer-readable recording medium such as a ROM or a semiconductor memory. The program may also be provided as a data signal via a network. The processing device 7 includes, for example, an acquisition unit 71, a storage unit 72, a processing unit 73, and a wired output unit 74 as functional configurations.

[0041] The acquisition unit 71 acquires the point cloud information Dm2 from the laser sensor 6 for each packet. The acquisition unit 71 adds a timestamp indicating the time when the point cloud information Dm2 is acquired to the point cloud information Dm2. The acquisition unit 71 outputs the point cloud information Dm2 with the timestamp added to the processing unit 73 for each packet. When the laser sensor 6 acquires one frame of point cloud information Dm2, the acquisition unit 71 acquires a one-frame completion flag from the laser sensor 6. In this case, the acquisition unit 71 adds a one-frame completion flag to the point cloud information Dm2 in addition to the above-mentioned timestamp. Therefore, when one frame of point cloud information Dm2 is acquired, both the above-mentioned timestamp and the one-frame completion flag are added to the point cloud information Dm2.

[0042] The storage unit 72 stores various setting information. The various setting information includes exclusion information indicating a detection exclusion range. The detection exclusion range is set in advance. For example, similar to the slave laser radar device 2, the user sets the detection exclusion range using an input device. The detection exclusion range set in the processing device 7 may be the same as the detection exclusion range set in the processing device 5, or may be different. When the same detection exclusion range is set in the processing device 5 and the processing device 7, the processing device 7 may transmit exclusion information indicating the detection exclusion range set in the processing device 7 to the processing device 5.

[0043] The processing unit 73 processes the point cloud information Dm2. Specifically, when the processing unit 73 receives the point cloud information Dm2 from the acquisition unit 51, the processing unit 73 performs a first process and a second process on the point cloud information Dm2. In the first process, the processing unit 73 excludes (deletes) excluded measurement point information of measurement points included in the detection exclusion range indicated by the exclusion information read from the storage unit 72 from the point cloud information Dm2. In other words, the first process is an exclusion process that excludes unnecessary excluded measurement point information from the point cloud information Dm2. As a result, measurement points that are not monitored are excluded from the point cloud information Dm2, and abnormal measurement point information caused by noise or the like is excluded.

[0044] In the second process, the processing unit 73 divides the monitoring area Rd into a plurality of areas, and when the density of the measurement points included in the area is higher than a threshold, deletes the target measurement point information including at least one measurement point in the area from the second point cloud information. That is, the second process is a thinning process that thins out the measurement points included in an area of ​​the monitoring area Rd with a high density of measurement points. For example, when the density of the measurement points in the area is higher than a threshold, the processing unit 73 may exclude the measurement points included in the area so that the density of the measurement points is equal to or lower than the threshold. As a result, the measurement points to be thinned out are excluded from the point cloud information Dm2. That is, the measurement point information of the measurement points to be thinned out is excluded from the point cloud information Dm2.

[0045] The processing unit 73 removes unnecessary measurement point information from the point cloud information Dm2 through the first process and the second process, and generates partial information Dp2 including the remaining measurement point information. The partial information Dp2 is the point cloud information Dm2 after processing by the processing unit 73. By removing unnecessary measurement point information from the point cloud information Dm2, the data amount of the partial information Dp2 becomes smaller than the data amount of the point cloud information Dm2. The processing unit 73 outputs the generated point cloud information Dm2 to the wireless output unit 50.

[0046] The processing unit 73 may perform the first process and the second process on the point cloud information Dm2 in order, or may perform the first process and the second process on the point cloud information Dm2 simultaneously. The processing unit 73 does not necessarily have to perform both the first process and the second process on the point cloud information Dm2, and may perform only one of the first process and the second process on the point cloud information Dm2. In this embodiment, the processing by the processing unit 73 means both the first process and the second process. The processing unit 73 may perform other processes on the point cloud information Dm2 in addition to the first process and the second process, or instead of the first process and the second process.

[0047] The wired output unit 74 outputs the partial information Dp2 for each packet to the outside of the processing device 7. Specifically, when the wired output unit 74 receives the partial information Dp2 from the processing unit 73, it transmits the partial information Dp2 for each packet to the detection device 8 via wired communication at a predetermined period.

[0048] The detection device 8 is a device that generates a detection result Dd regarding an object present in the monitoring area Rd based on the partial information Dp1 and the partial information Dp2. The detection device 8 is configured by, for example, an information processing device such as a computer. The physical configuration of the detection device 8 is similar to the physical configuration of the processing device 5. Each functional unit of the detection device 8 shown in FIG. 1 is realized by executing a program module for realizing each function in a computer constituting the detection device 8. A program including these program modules is provided by, for example, a computer-readable recording medium such as a ROM or a semiconductor memory. The program may also be provided as a data signal via a network. Note that the processing device 7 and the detection device 8 may be configured by one information processing device. In this case, a program including a program module for realizing the function of each functional unit of the processing device 7 and the detection device 8 may be provided.

[0049] The detection device 8 includes, as functional components, for example, an acquisition unit 81 (wired input unit), a storage unit 82, a synthesis unit 83, a detection unit 84, and an output unit 85. The synthesis unit 83 and the detection unit 84 configure a detection processing unit 86 that performs detection processing to generate a detection result Dd.

[0050] The acquisition unit 81 is connected by wire to the wired output unit 74 of the processing device 5, and acquires the partial information Dp1 from the wired output unit 74 for each packet. Furthermore, the acquisition unit 81 acquires the partial information Dp2 from the wireless input unit 80 for each packet. The wireless input unit 80 is wirelessly connected to the wireless output unit 50 via a communication line N (wireless communication), and acquires the partial information Dp1 from the wireless output unit 50 for each packet via wireless communication. Note that the acquisition unit 81 may also have the function of the wireless input unit 80. In this case, the wireless input unit 80 may be omitted.

[0051] Due to a transmission delay or the like, the timing at which the acquisition unit 81 receives the partial information Dp1 may differ from the timing at which the acquisition unit 81 receives the partial information Dp2, even for the same frame. In this embodiment, the partial information Dp1 is transmitted via wireless communication, whereas the partial information Dp2 is transmitted via wired communication. Therefore, the acquisition unit 81 receives the partial information Dp1 after receiving the partial information Dp2. The acquisition unit 81 outputs the acquired partial information Dp1 and partial information Dp2 to the storage unit 82.

[0052] The storage unit 82 stores the partial information Dp1 and the partial information Dp2. The storage unit 82 sorts the partial information Dp1 received from the processing device 5 by the time indicated by the time stamp, and stores the partial information Dp1. Similarly, the storage unit 82 sorts the partial information Dp2 received from the processing device 7 by the time indicated by the time stamp, and stores the partial information Dp2. If a one-frame completion flag is added to the partial information Dp2, the storage unit 82 stores the one-frame completion flag in association with the partial information Dp2.

[0053] The detection processing unit 86 performs a process of generating a detection result Dd based on the partial information Dp1 and the partial information Dp2. In this embodiment, the detection processing unit 86 starts generating a detection result Dd based on the partial information Dp1 and the partial information Dp2 at the earlier of the timing when the detection device 8 acquires the partial information Dp1 for one frame via wireless communication and the timing when a certain time has elapsed from the reference time. As described above, since the detection device 8 acquires the partial information Dp2 via wired communication, it is not expected that a significant delay will occur in the timing when the detection device 8 acquires the partial information Dp2. Therefore, the following description will be given on the assumption that the detection device 8 has already acquired the partial information Dp2 for one frame before the generation of the detection result Dd is started.

[0054] The timing at which the detection device 8 acquires one frame of partial information Dp1 via wireless communication is the timing at which the frame period elapses, assuming that the period during which the detection device 8 acquires one frame of partial information Dp1 is a frame period. Therefore, the timing at which the detection device 8 acquires one frame of partial information Dp1 via wireless communication repeatedly arrives at the timing at which the frame period elapses.

[0055] When the detection device 8 acquires partial information Dp2 with a one-frame completion flag added thereto after acquiring partial information Dp2 with a previous one-frame completion flag added thereto, the detection device 8 determines that it has acquired one frame's worth of partial information Dp2. When the detection device 8 acquires partial information Dp1 with a timestamp added thereto of the same time (or a time close to) as the partial information Dp2 with the one-frame completion flag added thereto, the detection device 8 can determine that it has acquired one frame's worth of partial information Dp1. Therefore, the timing at which the detection device 8 acquires one frame's worth of partial information Dp1 corresponds to the timing at which it acquires partial information Dp1 with a timestamp added thereto of the same time as the partial information Dp2 with the one-frame completion flag added thereto.

[0056] The timing when a certain time has passed since the reference time is the timing when a predetermined period based on the reference time has passed. Therefore, the timing when a certain time has passed since the reference time repeatedly arrives at the timing when the predetermined period has passed. If the timing when a certain time has passed since the reference time is later than the timing when the partial information Dp1 for one frame is acquired via wireless communication, the "reference time" may be, for example, the time when the detection device 8 acquires the partial information Dp1 for one frame last time. On the other hand, if the timing when a certain time has passed since the reference time is earlier than the timing when the partial information Dp1 for one frame is acquired via wireless communication, the time when a certain time has passed since the previous reference time may be the time when the detection processing unit 86 starts generating the detection result Dd when the timing when a certain time has passed since the reference time or the timing when the partial information Dp1 for one frame is acquired via wireless communication, whichever is earlier, arrives. Therefore, the "reference time" may be taken as the time when the generation of the previous detection result Dd starts.

[0057] The above-mentioned "certain time" may be, for example, a time desired by a user of the monitoring system 1. The "certain time" is set in response to a request from the user and may be changed according to the request from the user. The "certain time" is set so that the timing at which the certain time has passed from the reference time is at least later than the timing at which the detection device 8 acquires one frame of partial information Dp2 via wired communication. The timing at which the certain time has passed from the reference time may be earlier than the timing at which the detection device 8 acquires one frame of partial information Dp1 via wireless communication, or it may be later than that timing. The detection processing unit 86 determines whether the certain time has passed from the reference time by, for example, measuring the time from the reference time using a timer.

[0058] If the timing at which the detection device 8 acquires the partial information Dp1 for one frame via wireless communication is earlier than the timing at which a certain time has elapsed from the reference time, the detection processing unit 86 starts generating the detection result Dd based on the partial information Dp1 for one frame and the partial information Dp2 for one frame at the timing at which the detection device 8 acquires the partial information Dp1 for one frame. In this case, the detection processing unit 86 extracts the partial information Dp1 for one frame and the partial information Dp2 for one frame from the storage unit 82.

[0059] Specifically, the detection processing unit 86 extracts one frame's worth of partial information Dp2 based on the one frame completion flag. The time indicated by the timestamp of the partial information Dp2 to which the one frame completion flag has been added indicates the end time of the current one frame. The time following the time indicated by the timestamp of the partial information Dp2 to which the previous one frame completion flag has been added indicates the start time of the current frame. Therefore, the detection processing unit 86 extracts the sum of the partial information Dp2 acquired from the start time to the end time of one frame from the storage unit 82 as the partial information Dp2 for one frame.

[0060] The partial information Dp1 to which a time stamp indicating the same time (or close to) the end time of one frame is added is acquired at the end time of the current one frame. The partial information Dp1 to which a time stamp indicating the time next to the time indicated by the time stamp of the partial information Dp2 to which the previous one frame completion flag is added is acquired at the start time of the current one frame. The detection processing unit 86 extracts the total of the partial information Dp1 acquired from the start time to the end time of one frame from the storage unit 82 as the partial information Dp1 for one frame. That is, the detection processing unit 86 extracts the partial information Dp2 to which a time stamp indicating the same time as the extracted partial information Dp1 for one frame is added from the storage unit 82 as the partial information Dp2 for one frame. Then, the detection processing unit 86 starts generating the detection result Dd based on the extracted partial information Dp1 for one frame and the partial information Dp2 for one frame.

[0061] On the other hand, if the timing at which the detection device 8 acquires the partial information Dp1 for one frame via wireless communication is later than the timing at which a certain time has elapsed from the reference time, the detection processing unit 86 starts generating the detection result Dd based on the partial information Dp1 for less than one frame and the partial information Dp2 for one frame at the timing at which the certain time has elapsed from the reference time. In this case, the detection processing unit 86 extracts the partial information Dp1 for less than one frame and the partial information Dp2 for one frame from the storage unit 82. The partial information Dp1 for less than one frame is, for example, the total partial information Dp1 acquired from the start time of one frame to the time at which a certain time has elapsed from the reference time (i.e., the time before the end time of one frame). The detection processing unit 86 starts generating the detection result Dd based on the extracted partial information Dp1 for less than one frame and the partial information Dp2 for one frame.

[0062] If an event occurs M (M is an integer greater than or equal to 1) times in which the timing at which a certain amount of time has elapsed from the reference time arrives earlier than the timing at which the detection device 8 acquires one frame of partial information Dp2 via wired communication, the detection processing unit 86 stops generating the detection result Dd as an abnormality process.

[0063] Specifically, the detection result Dd based on the partial information Dp1 and the partial information Dp2 is generated as follows. First, the synthesis unit 83 of the detection processing unit 86 generates synthesis information Ds by synthesizing (merging) the partial information Dp2 with the partial information Dp1 of the same time (or a close time) as the partial information Dp2. Specifically, the synthesis unit 83 extracts the partial information Dp1 and the partial information Dp2 of the same time by referring to the timestamps added to the partial information Dp1 and the partial information Dp2, respectively. Then, the synthesis unit 83 synthesizes the extracted partial information Dp1 and the partial information Dp2.

[0064] More specifically, the synthesis unit 83 generates synthesis information Ds including a plurality of pieces of measurement point information included in the partial information Dp1 and a plurality of pieces of measurement point information included in the partial information Dp2. The synthesis information Ds may be expressed in the form of a table in which, for example, a plurality of pieces of measurement point information included in the partial information Dp1 and a plurality of pieces of measurement point information included in the partial information Dp2 are listed (arranged). The partial information Dp1 and the partial information Dp2 may include measurement point information of the same measurement point. Therefore, when two pieces of measurement point information are measurement point information of the same measurement point, the synthesis unit 83 may delete one of them. For example, when the distance between the position coordinates of the two pieces of measurement point information is equal to or less than a preset distance, the synthesis unit 83 may determine that these two pieces of measurement point information are measurement point information of the same measurement point. The synthesis unit 83 outputs the synthesis information Ds to the detection unit 84.

[0065] The detection unit 84 detects an object based on the synthesis information Ds. Specifically, when the detection unit 84 receives the synthesis information Ds from the synthesis unit 83, the detection unit 84 clusters a plurality of pieces of measurement point information included in the synthesis information Ds. That is, the detection unit 84 connects adjacent measurement points among a plurality of measurement points in the monitoring area Rd and divides them into clusters (lumps). The detection unit 84 detects the obtained cluster as a single detected object (such as a vehicle or a person). The detection unit 84 calculates the dimensions (width, depth, and height) and position of the detected object. The position of the detected object may be the coordinates of the four corners (front right end, front left end, rear right end, and rear left end) of the detected object, may be the average of the positions of the measurement point information included in the cluster, or may be the center of gravity position of the detected object.

[0066] The detection unit 84 outputs a detection result Dd relating to the detected object to the output unit 85. The detection result Dd includes dimensional information indicating the dimensions of the detected object, position information indicating the position of the detected object, and detection time information indicating the detection time when the detected object was detected. The detection time is, for example, the average time of the times indicated by the time information included in the measurement point information of each measurement point included in the cluster.

[0067] The detection unit 84 may track the detected object. That is, the detection unit 84 may associate an object ID with a detected object detected in a different frame (different time). The object ID is identification information that can uniquely identify a detected object. Specifically, the detection unit 84 determines whether a detected object detected in a current frame corresponds to any of the detected objects detected in a past frame based on the position and dimensions of the detected object, as well as the velocity and angular velocity estimated from past observation results.

[0068] When the detection unit 84 determines that a detected object detected in the current frame does not correspond to any of the detected objects detected in the past frames, the detection unit 84 assigns a new object ID to the detected object as a new detected object. When the detection unit 84 determines that a detected object detected in the current frame corresponds to a detected object detected in the past frame, the detection unit 84 assigns the object ID assigned to the corresponding detected object to the detected object detected in the current frame. The detection unit 84 deletes the object ID of a detected object that has not been detected for a long time among the detected objects to which an object ID has been assigned.

[0069] The problem of tracking (assigning IDs) multiple detected objects is called a multi-target tracking problem. The detection unit 84 tracks each detected object using a known algorithm. Examples of known algorithms include SNN (Suboptimal Nearest Neighbor), GNN (Global Nearest Neighbor), and JPDAF (Joint Probabilistic Data Association Filter). In this case, the detection unit 84 outputs the object ID, object position information, detection time information, and the like to the output unit 85 as the detection result Dd.

[0070] The output unit 85 outputs the detection result Dd to the outside of the detection device 8 (master laser radar device 3). The output unit 85 transmits the detection result Dd to, for example, an external device. Examples of the external device include a higher-level management system and a traffic control system. The detection result Dd may be transmitted by wireless communication or by wired communication. The output unit 85 may convert the data format of the detection result Dd into a data format that is easy for the external device to process, and transmit the converted detection result Dd to the external device.

[0071] Next, a description will be given of the processing performed by the slave laser radar device 2. Fig. 6 is a flowchart showing the partial information generation processing performed by the slave laser radar device 2. The partial information generation processing shown in Fig. 6 is started, for example, by starting up the slave laser radar device 2.

[0072] First, the laser sensor 4 synchronizes the time so that the time of the laser sensor 4 coincides with the time of the laser sensor 6 (step S11). For example, the laser sensor 4 sets the time using NTP.

[0073] After the time synchronization is performed, the laser sensor 4 sequentially irradiates the laser light to the multiple measurement points included in the irradiable area Ra, and receives the reflected light of the irradiated laser light to generate measurement point information of each measurement point in the irradiable area Ra. The laser sensor 4 starts irradiating the laser light at the same timing as the laser sensor 6 starts irradiating the laser light. Then, the laser sensor 4 outputs point cloud information Dm1 including one packet of multiple measurement point information to the processing device 5.

[0074] Next, the acquisition unit 51 acquires the point cloud information Dm1 for each packet from the laser sensor 4 (step S12). Then, the acquisition unit 51 outputs the acquired point cloud information Dm1 to the processing unit 53.

[0075] Next, the processing unit 53 reduces the data amount of the point cloud information Dm1 (step S13). Specifically, when the processing unit 53 receives the point cloud information Dm1 from the acquisition unit 51, the processing unit 53 performs a first process of excluding, from the point cloud information Dm1, excluded measurement point information of the measurement points included in the detection exclusion range indicated by the exclusion information read from the storage unit 52. Furthermore, the processing unit 53 performs a second process of dividing the monitoring area Rd into a plurality of divided areas, and deleting, from the point cloud information Dm1, target measurement point information including at least one measurement point of the divided area when the density of the measurement points included in the divided area is higher than a threshold value. Then, the processing unit 53 outputs partial information Dp1 including the remaining measurement point information to the wireless output unit 50.

[0076] Next, when the wireless output unit 50 receives the partial information Dp1 from the processing unit 53, it transmits the partial information Dp1 to the master laser radar device 3 via the communication line N (wireless communication) for each packet at a predetermined period (step S14). Then, the slave laser radar device 2 judges whether or not to end the process (step S15). If the slave laser radar device 2 judges not to end the process (step S15; NO), irradiation by the laser sensor 4 is performed again, and the processes of steps S12 to S15 are performed. On the other hand, if the slave laser radar device 2 judges to end the process (step S15; YES), the partial information generation process performed by the slave laser radar device 2 is ended. Note that the slave laser radar device 2 judges to end the process when the user performs an operation to stop monitoring, etc.

[0077] Next, a description will be given of the processing performed by the master laser radar device 3. Fig. 7 is a flowchart showing the partial information generation processing performed by the master laser radar device 3. The partial information generation processing shown in Fig. 7 is started, for example, when the master laser radar device 3 is started.

[0078] First, the laser sensor 6 synchronizes the time so that the time of the laser sensor 4 coincides with the time of the laser sensor 6 (step S31). For example, the laser sensor 6 sets the time using NTP.

[0079] After time synchronization, the laser sensor 6 sequentially irradiates a laser beam onto multiple measurement points included in the irradiable region Rb, and receives reflected light of the irradiated laser beam to generate measurement point information for each measurement point in the irradiable region Rb. Then, the laser sensor 6 outputs point cloud information Dm2 including one packet of multiple measurement point information to the processing device 7. When the laser sensor 6 acquires one frame's worth of point cloud information Dm2, it transmits a one-frame completion flag to the processing device 7.

[0080] Next, the acquisition unit 71 acquires the point cloud information Dm2 for each packet from the laser sensor 6 (step S32). Then, the acquisition unit 71 outputs the acquired point cloud information Dm2 to the processing unit 73. When a one frame completion flag is transmitted from the laser sensor 6, the acquisition unit 71 adds the one frame completion flag to the point cloud information Dm2, and outputs the point cloud information Dm2 with the one frame completion flag added to the processing unit 73.

[0081] Next, the processing unit 73 reduces the data amount of the point cloud information Dm2 (step S33). Specifically, when the processing unit 73 receives the point cloud information Dm2 from the acquisition unit 71, the processing unit 73 excludes from the point cloud information Dm2 the measurement point information of the measurement points included in the detection exclusion range indicated by the exclusion information read from the storage unit 72. Then, the processing unit 73 outputs partial information Dp2 including the remaining measurement point information to the wired output unit 74.

[0082] Next, when the wired output unit 74 receives the partial information Dp2 from the processing unit 73, it outputs the partial information Dp2 packet by packet to the detection device 8. Then, when the acquisition unit 81 of the detection device 8 receives the partial information Dp2 from the processing device 7, it outputs the partial information Dp2 to the storage unit 82 and stores it in the storage unit 82 (step S34).

[0083] Next, the master laser radar device 3 determines whether or not to end the process (step S35). If the master laser radar device 3 determines not to end the process (step S35; NO), irradiation by the laser sensor 6 is performed again, and the processes of steps S32 to S35 are performed. On the other hand, if the master laser radar device 3 determines to end the process (step S35; YES), the partial information generation process performed by the master laser radar device 3 ends. Note that the master laser radar device 3 determines to end the process when, for example, the user performs an operation to stop monitoring.

[0084] Next, the detection process performed by the master laser radar device 3 will be described. Additionally, the monitoring method of this embodiment performed by the master laser radar device 3 will be described. Fig. 8 is a flowchart showing the detection process performed by the master laser radar device. The detection process shown in Fig. 8 is started, for example, by starting up the master laser radar device 3.

[0085] First, the detection processing unit 86 uses a timer to count the time from a reference time (step S41). When step S41 is repeated, the detection processing unit 86 resets the timer and then counts the time from the reference time.

[0086] Next, the detection processing unit 86 judges whether or not the partial information Dp2 for one frame has been acquired from the processing device 7 via wired communication based on the one-frame completion flag added to the partial information Dp2 (step S42). For example, if the acquisition unit 81 has not acquired the partial information Dp2 with the one-frame completion flag added, the detection processing unit 86 judges that the partial information Dp2 for one frame has not been acquired (step S42; NO). In this case, the detection processing unit 86 judges whether or not a certain time has elapsed from the reference time (step S51).

[0087] When the detection processing unit 86 determines that the certain time has not passed since the reference time (step S51; NO), the process returns to step S42 and repeats the determination in step S42. On the other hand, when the detection processing unit 86 determines that the certain time has passed since the reference time (step S51; YES), the detection processing unit 86 determines whether or not the determination that the certain time has passed since the reference time has continued M times (step S52). Here, M is an integer equal to or greater than 1, and is appropriately set by the user, for example.

[0088] When the detection processing unit 86 determines that the determination that the certain time has passed from the reference time has not been made M times in a row (step S52; NO), the process returns to step S42 and repeats the determination in step S42. On the other hand, when the detection processing unit 86 determines that the determination that the certain time has passed from the reference time has been made M times in a row in step S51 (step S52; YES), the detection processing unit 86 determines that an abnormality has occurred and stops the subsequent processing (step S53).

[0089] When the detection processing unit 86 determines that the partial information Dp2 for one frame has been acquired (step S42; YES), it determines whether or not the partial information Dp1 for one frame has been acquired (step S43). For example, when the acquisition unit 81 acquires the partial information Dp1 at the same time (or a close time) as the partial information Dp2 to which the one-frame completion flag is added, the detection processing unit 86 determines that the partial information Dp1 for one frame has been acquired (step S43; YES). In this case, the detection processing unit 86 starts generating the detection result Dd.

[0090] On the other hand, if the acquisition unit 81 has not acquired the partial information Dp1 of the same time as the partial information Dp2 to which the one-frame completion flag has been added, the detection processing unit 86 determines that the partial information Dp1 for one frame has not been acquired (step S43; NO). In this case, the detection processing unit 86 determines whether or not a certain time has passed since the reference time (step S61). If the detection processing unit 86 determines that the certain time has not passed since the reference time (step S61; NO), the process returns to step S43 and repeats the determination of step S43. On the other hand, if the detection processing unit 86 determines that the certain time has passed since the reference time (step S61; YES), the detection processing unit 86 outputs an alarm indicating that the partial information Dp1 for one frame has not been acquired (step S62) and starts generating the detection result Dd.

[0091] Thus, in this embodiment, the detection processing unit 86 starts generating the detection result Dd at the earlier of the timing when the partial information Dp1 for one frame is acquired (step S43; YES) or the timing when a certain time has elapsed from the reference time (step S61; YES). Therefore, even if the detection processing unit 86 has not acquired the partial information Dp1 for one frame, the detection processing unit 86 starts generating the detection result Dd when a certain time has elapsed from the reference time.

[0092] When the detection processing unit 86 starts generating the detection result Dd, first, the synthesis unit 83 performs synthesis processing of the detection result Dd based on the partial information Dp1 and the partial information Dp2 (step S44). In step S46, the synthesis unit 83 synthesizes (merges) the partial information Dp2 and the partial information Dp1 having the same time as the partial information Dp2 to generate synthesis information Ds including a plurality of measurement point information included in the partial information Dp1 and a plurality of measurement point information included in the partial information Dp2. The synthesis unit 83 extracts the partial information Dp1 and the partial information Dp2 having the same time by, for example, referring to the time stamps added to the partial information Dp1 and the partial information Dp2, respectively. Then, the synthesis unit 83 synthesizes the extracted partial information Dp1 and the partial information Dp2. The synthesis unit 83 outputs the synthesis information Ds to the detection unit 84.

[0093] Next, the detection unit 84 detects an object based on the composite information Ds (step S45). Then, the detection unit 84 outputs a detection result Dd relating to the object to the output unit 85. Next, the output unit 85 transmits the detection result Dd to an external device (step S46). The output unit 85 may convert the data format of the detection result Dd into a data format that is easy for the external device to process, and transmit the converted detection result Dd to the external device. With this, the detection process of the master laser radar device 3 is completed.

[0094] The effects of the monitoring system 1 and the monitoring method according to the present embodiment described above will be described.

[0095] In this embodiment, the monitoring area Rd is monitored using the laser sensor 4 and the laser sensor 6 installed on the ground. This reduces blind spots in the monitoring area Rd, so that the detection accuracy can be improved. Furthermore, in this embodiment, the detection device 8 that detects an object present in the monitoring area Rd acquires the partial information Dp1 via wireless communication, while acquiring the partial information Dp2 via wired communication. In this case, the timing at which the detection device 8 acquires the partial information Dp1 via wireless communication tends to be delayed with respect to the timing at which the detection device 8 acquires the partial information Dp2 via wired communication. In this case, from the viewpoint of improving the detection accuracy, if the detection device 8 starts generating the detection result Dd at the timing at which both the partial information Dp1 for one frame and the partial information Dp2 for one frame are available, it is assumed that the generation of the detection result Dd by the detection device 8 will also be delayed according to the delay in the timing at which the detection device 8 acquires the partial information Dp1 for one frame. In contrast, in this embodiment, generation of the detection result Dd based on the partial information Dp1 and the partial information Dp2 is started at the earlier of the timing when the detection device 8 acquires the partial information Dp1 for one frame via wireless communication and the timing when a certain time has elapsed from the reference time. In this case, even if there is a delay in the timing when the detection device 8 acquires the partial information Dp1 for one frame via wireless communication, the detection result Dd can be generated at the timing when a certain time has elapsed from the reference time. As a result, the detection result Dd can be provided to the user at any timing desired by the user without waiting for the timing when the detection device 8 acquires the partial information Dp1 for one frame. Therefore, according to this embodiment, information can be provided to the user at a desired timing while improving the detection accuracy.

[0096] As in this embodiment, the detection processing unit 86 repeatedly generates the detection result Dd each time the earlier timing arrives, and the reference time may be the time when the earlier timing arrived the previous time. In this case, it is easy to adjust the timing to start generating the detection result Dd, so that it is possible to easily provide the detection result Dd to the user at a desired timing.

[0097] As in this embodiment, the detection processing unit 86 may stop the process of generating the detection result Dd when an event occurs M times in which the timing when a certain time has elapsed from the reference time arrives earlier than the timing when the detection device 8 acquires one frame of partial information Dp2 via wired communication. In this case, it is possible to prevent a detection result Dd with low detection accuracy from being provided to a user.

[0098] As in this embodiment, the processing unit 73 may perform a second process of dividing the monitoring area Rd into a plurality of areas, and deleting target measurement point information including at least one measurement point in the area from the point cloud information Dm1 when the density of the measurement points included in the area is higher than a threshold value. In this case, the data amount of the partial information Dp1 after the process is even smaller than the data amount of the partial information Dp1 before the process. In this case, the time required to transmit the partial information Dp1 from the processing device 7 to the detection device 8 can be further shortened. This makes it possible to more effectively suppress delays in wireless communication between the processing device 7 and the detection device 8. As a result, it is possible to more effectively suppress a situation in which the timing at which the detection device 8 acquires the partial information Dp1 via wireless communication is significantly delayed from the timing at which the detection device 8 acquires the partial information Dp2 via wired communication.

[0099] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments.

[0100] <Variation 1> 9, the monitoring system 1A may include a master laser radar device 3A that does not include the above-mentioned processing device 7. When the master laser radar device 3A does not include the above-mentioned processing device 7, the point cloud information Dm2 acquired by the laser sensor 6 is directly transmitted to an acquisition unit 81 of the detection device 8 via wired communication. In this case, the acquisition unit 81 also has a function equivalent to, for example, the acquisition unit 71 of the above-mentioned processing device 7. In the monitoring system 1A, the detection processing unit 86 generates a detection result Dd based on the partial information Dp1 that has been processed by the processing device 5 and the point cloud information Dm2 that has not been processed.

[0101] Since the point cloud information Dm2 is transmitted from the processing device 7 to the detection device 8 via wired communication, there is little concern that a delay will occur in the timing at which the detection device 8 acquires the point cloud information Dm2 even if the point cloud information Dm2 is transmitted as is to the detection device 8. Therefore, the monitoring system 1A does not include the processing device 7 for performing the above-mentioned processing on the point cloud information Dm2. This simplifies the overall configuration of the monitoring system 1A.

[0102] <Variation 2> For example, as shown in FIG. 10, the monitoring system 1B may include a master laser radar device 3B in which the processing device 7 described above is omitted. The detection device 8A of the master laser radar device 3B further includes a point cloud processing unit 87. The point cloud processing unit 87 has a function corresponding to the processing unit 73 of the processing device 7 described above. The acquisition unit 81 also has a function corresponding to, for example, the acquisition unit 71 of the processing device 7 described above. When the point cloud processing unit 87 receives the point cloud information Dm2 from the acquisition unit 81, the point cloud processing unit 87 generates partial information Dp2 by performing the first processing and the second processing described above on the point cloud information Dm2. The storage unit 82 stores the partial information Dp1 received from the acquisition unit 81 and the partial information Dp2 generated by the point cloud processing unit 87. The detection processing unit 86 generates a detection result Dd based on the partial information Dp1 processed by the processing unit 53 and the partial information Dp2 processed by the point cloud processing unit 87.

[0103] In the monitoring system 1B, as in the above-mentioned monitoring system 1A, the processing device 7 is omitted, and therefore the overall configuration of the monitoring system 1B is simplified. Furthermore, in the monitoring system 1B, the detection device 8A includes a point cloud processing unit 87, and therefore the detection processing unit 86 can generate the detection result Dd based on the point cloud information Dm1 and point cloud information Dm2, which have a small amount of data. This reduces the processing load when the detection processing unit 86 generates the detection result Dd.

[0104] <Other Modifications> For example, the intersection C may be a T-junction. The location where the monitoring area Rd is set is not limited to an intersection, but may be a junction where two or more roads join, a junction between an exit of a facility such as a building and a road, or a midway point on a road. The monitoring area Rd may be set on a general road or an expressway. The monitoring area Rd may be set at a railroad crossing, a factory, a work site, or the like.

[0105] The arrangement of the slave laser radar device 2 and the master laser radar device 3 is not limited to the arrangement shown in Figures 2 and 3. The monitoring system 1 may include two or more slave laser radar devices 2. Each slave laser radar device 2 may include a detection device 8. For example, if the master laser radar device 3 fails, the master laser radar device 3 may be stopped and any one of the slave laser radar devices 2 may operate as the master laser radar device to continue the detection process.

[0106] In the above embodiment, the slave laser radar device 2 and the master laser radar device 3 are each configured as one device, but may be configured as two or more devices. For example, the processing device 5 may be separate from the slave laser radar device 2. The processing device 7 and the detection device 8 may be separate from the master laser radar device 3.

[0107] The detection device 8 may be configured as an individual computer (information processing device) that does not have a function as a laser radar. In this case, a slave laser radar device 2 is provided in place of the master laser radar device 3.

[0108] In the above embodiment, the slave laser radar device 2 and the master laser radar device 3 are fixed to the support member P, but the processing devices 5, 7 and the detection device 8 do not have to be fixed to the support member P.

[0109] The monitoring system 1 (slave laser radar device 2) may not include a laser sensor 4. In this case, the processing device 5 acquires point cloud information Dm1 from an external laser sensor 4. Similarly, the monitoring system 1 (master laser radar device 3) may not include a laser sensor 6. In this case, the processing device 7 acquires point cloud information Dm2 from an external laser sensor 6.

[0110] The processing device 5 may include a laser sensor 4. The processing device 7 may include a laser sensor 6. As the laser sensors 4 and 6, a three-dimensional laser radar capable of emitting laser light in all directions may be used.

[0111] In the above embodiment, the laser sensor 4 outputs a plurality of pieces of measurement point information to the processing device 5 for each packet, but the plurality of pieces of measurement point information may be output to the processing device 5 in a unit other than one packet. For example, the laser sensor 4 may output the measurement point information one by one in sequence to the processing device 5. Similarly, the laser sensor 6 may output a plurality of pieces of measurement point information to the processing device 7 in a unit other than one packet. The laser sensor 6 may output the measurement point information one by one in sequence to the processing device 7.

[0112] In the above embodiment, the processing device 5 transmits the partial information Dp1 for one packet to the detection device 8, but may transmit the partial information Dp1 for two or more packets together to the detection device 8. Similarly, in the above embodiment, the processing device 7 transmits the partial information Dp2 for one packet to the detection device 8, but may transmit the partial information Dp2 for two or more packets together to the detection device 8.

[0113] The master laser radar device 3 may perform further processing using the detection result Dd. For example, the master laser radar device 3 may monitor for vehicles violating traffic laws using the detection result Dd.

[0114] For example, when the distance between two intersections is short, a master laser radar device 3 may be installed at each of the two intersections, and one slave laser radar device 2 may be installed at the midpoint of the road connecting the two intersections. In this case, one slave laser radar device 2 may belong to two monitoring systems and transmit partial information Dp1 to the master laser radar device 3 of each monitoring system. In this example, the monitoring areas Rd in the two monitoring systems are different from each other.

[0115] <Additional Notes> The present disclosure provides, [1] "a monitoring system for monitoring a monitoring area using a first laser sensor and a second laser sensor, each of which is installed on the ground and emits laser light toward an irradiatable area including at least a part of the monitoring area, and receives reflected light of the laser light to generate measurement point information including position coordinates of each measurement point within the irradiatable area, a detection device for detecting an object present in the monitoring area, The detection device includes: a wireless input unit that acquires, via wireless communication, first point cloud information including a plurality of pieces of measurement point information generated by the first laser sensor; a wired input unit that acquires second point cloud information including a plurality of pieces of measurement point information generated by the second laser sensor via wired communication; a detection processing unit that generates a detection result regarding the object present in the monitoring area based on the first point cloud information and the second point cloud information; Including, The detection processing unit is a monitoring system which starts generating the detection result based on the first point cloud information and the second point cloud information at the earlier of the timing when the detection device acquires one frame of the first point cloud information via wireless communication, and the timing when a certain amount of time has elapsed from a reference time."

[0116] The present disclosure further describes, [2] "the detection processing unit repeatedly generates the detection result each time the earlier timing arrives, The reference time is the time when the previous earlier timing occurred. The monitoring system described in [1].

[0117] The present disclosure further describes, [3] "the detection processing unit stops the process of generating the detection result when an event occurs M (M: integer equal to or greater than 1) times in which the timing at which the certain time has elapsed from the reference time arrives earlier than the timing at which the detection device acquires the second point cloud information for one frame via wired communication; The monitoring system according to [1] or [2].

[0118] The present disclosure further includes, [4] "a processing device wirelessly connected to the wireless input unit, processing the first point cloud information acquired from the first laser sensor, and transmitting the processed first point cloud information to the wireless input unit; The processing device includes: a processing unit that performs a first process of deleting excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the first point cloud information, The detection processing unit is generating the detection result based on the first point cloud information after the processing by the processing unit and the second point cloud information from which a process of deleting excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range has not been performed; The monitoring system according to any one of [1] to [3].

[0119] The present disclosure further includes, [5] "a processing device wirelessly connected to the wireless input unit, processing the first point cloud information acquired from the first laser sensor, and transmitting the processed first point cloud information to the wireless input unit; The processing device includes: a processing unit that performs a first process of deleting first excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the first point cloud information, The detection device includes: The method further includes a point cloud processing unit that performs a first process of deleting second excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the second point cloud information, The detection processing unit generates the detection result based on the first point cloud information after processing by the processing unit and the second point cloud information after processing by the point cloud processing unit. The monitoring system according to any one of [1] to [3].

[0120] The present disclosure states, [6] "The point cloud processing unit is a second process is further performed in which the monitoring area is divided into a plurality of areas, and when a density of the measurement points included in the area is higher than a threshold, target measurement point information including at least one measurement point in the area is deleted from the second point cloud information. The monitoring system described in [5].

[0121] The disclosure states, [7] "the processing unit is a second process is further performed in which the monitoring area is divided into a plurality of areas, and when a density of the measurement points included in the area is higher than a threshold, target measurement point information including at least one measurement point in the area is deleted from the first point cloud information. The monitoring system according to any one of [4] to [6].

[0122] The present disclosure provides, [8] "a monitoring method implemented by a monitoring system that monitors a monitoring area using a first laser sensor and a second laser sensor, each of which is installed on the ground and emits laser light toward an irradiatable area including at least a part of the monitoring area, and receives reflected light of the laser light to generate measurement point information including position coordinates of each measurement point within the irradiatable area, acquiring, via wireless communication, first point cloud information including a plurality of pieces of measurement point information generated by the first laser sensor; acquiring second point cloud information including a plurality of pieces of measurement point information generated by the second laser sensor via wired communication; generating a detection result regarding an object present in the monitoring area based on the first point cloud information and the second point cloud information; Equipped with In the step of generating the detection result, a monitoring method in which generation of the detection result based on the first point cloud information and the second point cloud information is started at the earlier of the timing when the detection device acquires one frame of the first point cloud information via wireless communication, and the timing when a certain amount of time has elapsed from a reference time." [Explanation of symbols]

[0123] 1,1A,1B Monitoring System 4 Laser sensor (first laser sensor) 5 Processing equipment 6 Laser sensor (second laser sensor) 7 Processing Equipment 8,8A Detector 53,73 Processing section 80 Wireless input section 81 Acquisition unit (wired input unit) 86 Detection processing section 87 Point Cloud Processing Unit Dd detection result Dm1 Point cloud information (first point cloud information) Dm2 point cloud information (second point cloud information) Dp1 partial information (1st point cloud information) Dp2 partial information (second point cloud information) Ra irradiation area Rb irradiation area Rd monitoring area

Claims

1. A monitoring system that monitors a monitoring area using a first laser sensor and a second laser sensor, each of which is installed on the ground and irradiates a laser light toward an irradiable area including at least a part of the monitoring area and receives reflected light of the laser light to generate measurement point information including position coordinates of each measurement point within the irradiable area, a detection device for detecting an object present in the monitoring area, The detection device includes: a wireless input unit that acquires, via wireless communication, first point cloud information including a plurality of pieces of measurement point information generated by the first laser sensor; a wired input unit that acquires second point cloud information including a plurality of pieces of measurement point information generated by the second laser sensor via wired communication; a detection processing unit that generates a detection result regarding the object present in the monitoring area based on the first point cloud information and the second point cloud information; Including, The detection processing unit is A monitoring system that starts generating the detection result based on the first point cloud information and the second point cloud information at the earlier of the timing when the detection device acquires one frame of the first point cloud information via wireless communication, or the timing when a certain amount of time has elapsed from a reference time.

2. the detection processing unit repeatedly generates the detection result each time the earlier timing arrives; The reference time is the time when the previous earlier timing occurred. The monitoring system of claim 1 .

3. the detection processing unit suspends the process of generating the detection result when an event occurs M times (M: an integer equal to or greater than 1) in which the timing at which the certain time has elapsed from the reference time arrives earlier than the timing at which the detection device acquires the one frame of the second point cloud information via wired communication. The monitoring system of claim 1 .

4. a processing device that is wirelessly connected to the wireless input unit, processes the first point cloud information acquired from the first laser sensor, and transmits the processed first point cloud information to the wireless input unit; The processing device includes: a processing unit that performs a first process of deleting excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the first point cloud information, The detection processing unit is generating the detection result based on the first point cloud information after the processing by the processing unit and the second point cloud information from which a process of deleting excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range has not been performed; The monitoring system of claim 1 .

5. a processing device that is wirelessly connected to the wireless input unit, processes the first point cloud information acquired from the first laser sensor, and transmits the processed first point cloud information to the wireless input unit; The processing device includes: a processing unit that performs a first process of deleting first excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the first point cloud information, The detection device includes: a point cloud processing unit that performs a first process of deleting second excluded measurement point information including position coordinates of measurement points included in a preset detection exclusion range from the second point cloud information, The detection processing unit generates the detection result based on the first point cloud information after processing by the processing unit and the second point cloud information after processing by the point cloud processing unit. The monitoring system of claim 1 .

6. The point cloud processing unit includes: a second process is further performed in which the monitoring area is divided into a plurality of areas, and when a density of the measurement points included in the area is higher than a threshold, target measurement point information including at least one measurement point in the area is deleted from the second point cloud information. The monitoring system according to claim 5.

7. The processing unit includes: a second process is further performed in which the monitoring area is divided into a plurality of areas, and when a density of the measurement points included in the area is higher than a threshold, target measurement point information including at least one measurement point in the area is deleted from the first point cloud information. A monitoring system according to any one of claims 4 to 6.

8. A monitoring method implemented by a monitoring system that monitors a monitoring area using a first laser sensor and a second laser sensor, each of which is installed on the ground and irradiates a laser light toward an irradiatable area including at least a part of the monitoring area and receives reflected light of the laser light to generate measurement point information including position coordinates of each measurement point within the irradiatable area, comprising: acquiring, via wireless communication, first point cloud information including a plurality of pieces of measurement point information generated by the first laser sensor; acquiring second point cloud information including a plurality of pieces of measurement point information generated by the second laser sensor via wired communication; generating a detection result regarding an object present in the monitoring area based on the first point cloud information and the second point cloud information; Equipped with In the step of generating the detection result, A monitoring method, which starts generating the detection result based on the first point cloud information and the second point cloud information at the earlier of the timing when one frame of the first point cloud information is acquired via wireless communication or the timing when a certain amount of time has elapsed from a reference time.

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