Security monitoring system

Abstract

To provide a safety monitoring system for monitoring whether or not a tool for falling prevention is appropriately used.SOLUTION: A safety monitoring system includes: an imaging device for imaging a work site; a tool for falling prevention to be worn by a worker of the work site; and an information processing device connected communicably to the imaging device and the tool for falling prevention. The tool for falling prevention includes: a wireless tag; and a wireless reader capable of reading the wireless tag. The information processing device includes: a person detection part for detecting a person corresponding to the worker from a photographed image; a height calculation part for calculating height of a work position of the worker on the basis of the image; and a high place work determination part for determining whether or not the height is equal to or more than a prescribed threshold. When the height is equal to or more than the prescribed threshold, the high place work determination part generates a first signal to actuate the wireless reader.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One embodiment of the present invention relates to a fall prevention device worn by a worker during high-altitude work. Another embodiment of the present invention relates to a safety monitoring system for monitoring the use of a fall prevention device for a worker.

Background Art

[0002] At a work site, various devices or facilities are used. For safe work, it is important that these devices or facilities are used correctly. For example, a worker performing high-altitude work is obliged to use a fall prevention device (also referred to as a safety belt). The fall prevention device is equipped with a hook, and by hanging the hook on a handrail or a main rope at the work site, the fall of the worker is prevented. Therefore, Patent Document 1 discloses a system for monitoring the use state of the hook of a fall prevention device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the fall prevention device disclosed in Patent Document 1 requires a pressure sensor with a predetermined structure to be attached to a predetermined position of the hook, and has a complicated configuration. Therefore, a monitoring system for a fall prevention device with higher versatility has been desired.

[0005] One embodiment of the present invention aims to provide a highly versatile fall prevention device in view of the above problems. Another embodiment of the present invention aims to provide a safety monitoring system for monitoring whether a fall prevention device is being used properly.

Means for Solving the Problems

[0006] The fall prevention device according to an embodiment of the present invention includes a belt worn by an operator, a lanyard connected to the belt and including a hook with a wireless tag attached thereto, a hook holder provided on the belt for hooking and holding the hook, and a control device provided on the belt and including a wireless reader capable of reading the wireless tag.

[0007] When the belt is worn by the operator, the control device may be positioned within 30 cm from the wireless tag when the hook is hooked on the hook holder.

[0008] The control device may further include a control unit that generates a second signal when the wireless reader acquires the identification information of the wireless tag.

[0009] The control device may further include a sound output unit that outputs a warning sound based on the second signal.

[0010] The control device may further include a communication unit, and the wireless reader may be operated by a first signal for operating the wireless reader received by the communication unit.

[0011] The safety monitoring system according to an embodiment of the present invention includes an imaging device that photographs a work site, a fall prevention device worn by an operator at the work site, and an information processing device communicably connected to the imaging device and the fall prevention device. The fall prevention device includes a wireless tag and a wireless reader capable of reading the wireless tag. The information processing device includes a person detection unit that detects a person corresponding to the operator from the photographed image, a height calculation unit that calculates the height of the work position of the operator based on the image, and an elevated work determination unit that determines whether the height is equal to or greater than a predetermined threshold. When the height is equal to or greater than the predetermined threshold, the elevated work determination unit generates a first signal for operating the wireless reader.

[0012] The fall prevention device may further include a control unit that controls the wireless reader based on the first signal, and the control unit may generate a second signal to be transmitted to the information processing device when the wireless reader acquires the identification information of the wireless tag.

[0013] The fall prevention device may further include a sound output unit that outputs a warning sound when the second signal is generated.

[0014] The information processing device may further include an unsafe behavior information generation unit that generates unsafe behavior information to be transmitted to a predetermined information terminal based on the second signal.

[0015] The person detection unit may detect a person in the image based on a marker attached to a helmet worn by the worker.

[0016] The first signal may be transmitted to the fall prevention device including a reader associated with the marker.

[0017] The height calculation unit may calculate the height based on an object detected in the image.

Advantages of the Invention

[0018] The fall prevention device according to an embodiment of the present invention has high versatility and excellent productivity. Further, the safety monitoring system according to an embodiment of the present invention can determine whether the fall prevention device is being properly used and can alert the worker in high-place work about safety. Therefore, in high-place work, disasters such as the worker falling can be prevented in advance.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0020] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. Note that the embodiments are merely examples, and those that can be easily conceived by those skilled in the art by appropriately changing while maintaining the gist of the invention are naturally included in the scope of the present invention. Also, for the sake of clearer explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the actual aspect. However, the illustrated shape is merely an example and does not limit the interpretation of the present invention.

[0021] In the present specification, for the sake of convenience of explanation, terms such as "upper", "above", or "upper part", or "lower", "below", or "lower part" are used for explanation, but it is only explaining the vertical relationship of each component. For example, when explaining the positional relationship of the components of a structure, based on the normal usage mode of the structure, the surface side where the structure is installed (for example, the floor surface side) may be regarded as "lower", "below", or "lower part".

[0022] In the present specification, the characters "first", "second", or "third" attached to each component are for convenience of distinguishing each component and have no further meaning unless otherwise specified.

[0023] In this specification and the drawings, when collectively representing a plurality of identical or similar configurations, the same reference numerals are used, and when separately representing each of these plurality of configurations, they may be represented with appended capital or small letters of the alphabet. Further, when separately representing a plurality of parts within one configuration, hyphens and natural numbers may be used.

[0024] In this specification, an RFID reader and an RFID tag are each an example of a wireless reader and a wireless tag, respectively, but for convenience, they are described as an RFID reader and an RFID tag. That is, the description of the RFID reader and the RFID tag is not limited to itself and can be paraphrased as a wireless reader and a wireless tag. Note that the wireless tag may include any one of a memory, an antenna, and a battery. Further, the wireless tag may include a contactless IC card.

[0025] With reference to FIGS. 1 to 6, the configuration of a safety monitoring system 10 according to an embodiment of the present invention and the monitoring process of a work site using the safety monitoring system 10 will be described.

[0026] [1. Configuration of Safety Monitoring System 10] FIG. 1 is a schematic diagram for explaining the outline of a safety monitoring system 10 according to an embodiment of the present invention. The safety monitoring system 10 includes a fall prevention device 100, an imaging device 200, and an information processing device 300. The fall prevention device 100 is worn by a worker 500 who performs work at height. The imaging device 200 can photograph a work site including the worker 500 who performs work at height. Since the imaging device 200 is communicably connected to the information processing device 300, the image captured by the imaging device 200 is transmitted to the information processing device 300. In the information processing device 300, it is possible to determine whether or not the worker 500 is performing work at height based on the captured image. Further, the information processing device 300 is communicably connected to the fall prevention device 100, and the information processing device 300 can determine whether or not the fall prevention device 100 is being properly used. That is, the safety monitoring system 10 is a system that identifies the worker 500 who performs work at height based on the captured image and monitors that the identified worker 500 is properly using the fall prevention device 100.

[0027] First, with reference to FIG. 2, the configuration of the fall prevention device 100 worn by the worker 500 will be described.

[0028] FIG. 2 is a schematic diagram showing the configuration of the fall prevention device 100 according to an embodiment of the present invention. The fall prevention device 100 includes a pair of shoulder belts 110, a chest belt 111, a waist belt 112, a pair of leg belts 113, a rope 120, a hook 130, a hook holder 140, an RFID tag 150, and a control device 160. Note that the pair of shoulder belts 110, the chest belt 111, the waist belt 112, and the pair of leg belts 113 may be collectively referred to as a belt. Also, the rope 120 and the hook 130 may be collectively referred to as a lanyard.

[0029] A pair of shoulder belts 110 are wound around both shoulders of the operator 500. The pair of shoulder belts 110 are connected via a chest belt 111 at the height of the operator 500's chest. A waist belt 112 is wound around the waist of the operator 500. Also, the pair of shoulder belts 110 are connected via the waist belt 112 at the height of the operator 500's waist. A pair of leg belts 113 are wound around both legs of the operator 500. In this way, the operator 500 can wear the belts of the fall arrest device 100.

[0030] One end of the rope 120 is connected to the hook 130. Although not shown, both ends of the pair of shoulder belts 110 are connected to a locking device (D-ring) on the back of the operator 500. The other end of the rope 120 is connected to a locking device. Note that the other end of the rope 120 may be connected to the locking device via a shock absorber. In this way, the lanyard is connected to the belt.

[0031] The hook 130 includes a hook-shaped portion having a hook shape and a single-opening wing that opens and closes the opening of the hook-shaped portion. When using the hook 130, the single-opening wing is operated to open the opening of the hook-shaped portion, and the hook-shaped portion can be hooked onto a structure such as a handrail or a main rope. When not using the hook 130, the hook 130 is hooked and held on a hook holder 140 provided on the shoulder belt 110. Note that the position where the hook holder 140 is provided is not limited to the shoulder belt 110. The hook holder 140 may be provided on the chest belt 111 or the waist belt 112.

[0032] As described above, the fall arrest device 100 is a so-called full harness type fall arrest device, but the fall arrest device 100 includes an RFID tag 150 and a control device 160 as described above.

[0033] The RFID tag 150 is a recording medium containing identification information. The identification information can be written to or read from the RFID tag 150 in a non-contact manner using wireless communication. The RFID tag 150 is attached to the hook 130 and contains identification information for identifying the fall arrest device 100. Although the details of the control device 160 will be described later, it includes an RFID reader capable of reading the RFID tag 150. The control device 160 is provided on the chest belt 111. Therefore, when the RFID tag 150 is within the range of communication with the RFID reader of the control device 160, the RFID reader can read the identification information of the RFID tag 150. In other words, when the hook 130 is within the range of a predetermined distance from the control device 160, the control device 160 can acquire the identification information for identifying the fall arrest device 100.

[0034] The control device 160 is provided at a position within 30 cm from the hook holder 140 when the worker 500 wears the fall arrest device 100. The communication distance between the RFID tag 150 and the RFID reader of the control device 160 is within 50 cm, preferably within 30 cm. Therefore, when the hook 130 is hooked and held by the hook holder 140, the RFID tag 150 attached to the hook 130 is within the range of communication with the RFID reader of the control device 160, and the control device 160 can acquire the identification information of the RFID tag 150. On the other hand, when the hook 130 is used and removed from the hook holder 140, the RFID tag 150 attached to the hook 130 is located outside the range of communication with the RFID reader of the control device 160, so the control device 160 cannot acquire the identification information of the RFID tag 150.

[0035] Therefore, in the fall arrest device 100, based on whether the control device 160 can acquire the identification information of the RFID 150, it is possible to determine whether the worker 500 wearing the fall arrest device 100 is using the hook 130.

[0036] Next, with reference to FIG. 3, the overall configuration of the safety monitoring system 10 will be described.

[0037] FIG. 3 is a block diagram showing the configuration of a safety monitoring system 10 according to an embodiment of the present invention. The control device 160 and the imaging device 200 are communicably connected to the information processing device 300 via the network NW. The network NW is preferably wireless, such as the Internet or the like. The control device 160 is, as described above, a part of the configuration of the fall prevention device 100, and includes a control unit 161, an RFID reader 162, a sound output unit 163, and a communication unit 164. The imaging device 200 includes an imaging unit 210 and a communication unit 220. The information processing device 300 includes a person detection unit 310, a height calculation unit 320, a high-altitude work determination unit 330, an unsafe behavior information generation unit 340, and a communication unit 350.

[0038] The imaging unit 210 can photograph the work site and generate an image. The imaging unit 210 is, for example, a camera including a solid-state imaging device such as a CCD (Charge-Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor.

[0039] The communication unit 220 is a communication interface capable of transmitting and receiving information or data, and can transmit the image photographed by the imaging unit 210 to the information processing device 300.

[0040] The imaging device 200 may be installed at a predetermined position in the work site and photograph the work site within the angle of view, or may be attached to a workbench (high-altitude workbench) or the helmet of the worker 500 and photograph the work site while moving with the worker 500. Further, the imaging device 200 may be mounted on a moving body capable of moving in the work site, such as a drone or an autonomous mobile robot.

[0041] The information processing device 300 is a so-called computer that can perform arithmetic processing using information or data. The information processing device 300 includes, for example, a central processing unit (CPU), a microprocessor (MPU), or a graphics processing unit (GPU). The information processing device 300 also includes a storage device such as a random access memory (RAM), a read-only memory (ROM), a flash memory, a hard disk drive (HDD), or a solid state drive (SSD), or a communication interface.

[0042] The person detection unit 310, the height calculation unit 320, the high-altitude work determination unit 330, and the unsafe behavior information generation unit 340 can function by a computer executing a program stored in a storage device. The communication unit 350 can receive information or data from the imaging device 200 and the control device 160, or transmit information or data to the control device 160. The communication unit 350 can also transmit information or data to the information terminal 400 of a worker or supervisor at the work site. The information terminal 400 is, for example, a notebook computer, a tablet, or a smartphone, but is not limited thereto.

[0043] The person detection unit 310 can detect a person corresponding to the worker 500 from an image. For example, the person detection unit 310 can detect a person in the image based on a marker assigned to the worker 500. The details of the person detection unit 310 will be described later.

[0044] The height calculation unit 320 can calculate the height of the working position of the worker 500 performing high-altitude work. The details of the height calculation unit 320 will be described later.

[0045] The high-altitude work determination unit 330 can determine whether the work of the worker 500 is high-altitude work based on the height calculated by the height calculation unit 320. The high-altitude work determination unit 330 can also generate a first signal for activating the RFID reader 162 when the work of the worker 500 is high-altitude work. The details of the high-altitude work determination unit 330 will be described later.

[0046] Based on the second signal described later, the unsafe action information generation unit 340 can generate unsafe action information. The generated unsafe action information may be transmitted to a predetermined information terminal such as a worker or supervisor at the work site.

[0047] The control device 160 is also a so-called computer that can perform arithmetic processing using information or data. The control unit 161 can function by executing a program stored in the storage device by the computer.

[0048] The control unit 161 can control the RFID reader 162 and the sound output unit 163. Further, the control unit 161 determines whether or not the identification information of the RFID tag 150 has been acquired, and when the identification information of the RFID tag 150 has been acquired, can generate a second signal including information regarding the unsafe action of the worker 500. The details of the control unit 161 will be described later.

[0049] The RFID reader 162 is as described above. That is, the RFID reader 162 can read the identification information of the RFID tag 150.

[0050] The sound output unit 163 includes a sound source and a speaker, is pre-produced, and can reproduce and output a warning sound recorded in the sound source. The warning sound may be a buzzer sound or may be a voice such as "Please use the hook of the fall arrest device."

[0051] The communication unit 164 is an interface capable of transmitting and receiving information or data, can receive the first signal transmitted from the information processing device 300, or transmit the second signal generated by the control unit 161 to the information processing device 300.

[0052] [2. Monitoring Process at the Work Site Using the Safety Monitoring System 10] FIG. 4 is a flowchart for explaining the monitoring process of a work site using the safety monitoring system 10 according to an embodiment of the present invention. FIGS. 5 and 6 are schematic diagrams for explaining a part of the monitoring process executed by the safety monitoring system 10 according to an embodiment of the present invention, respectively. The monitoring process of the work site using the safety monitoring system 10 is started by the imaging device 200 photographing the work site. Hereinafter, the monitoring process (steps S110 to S190) executed by the information processing device 300 and the control device 160 based on the image transmitted from the imaging device 200 will be described.

[0053] In step S110, the person detection unit 310 detects a person corresponding to the worker 500 from the image. As shown in FIG. 2, the worker 500 performing high-altitude work wears a helmet 510, and a marker 520 (for example, a helmet band, etc.) for identifying the worker 500 is attached to the helmet 510. Therefore, the person detection unit 310 can detect a person corresponding to the worker 500 from the image based on the marker 520. Further, the marker 520 assigned to the worker 500 and the fall arrest device 100 worn by the worker 500 are pre-associated and registered. Therefore, based on the marker 520, the fall arrest device 100 worn by the worker 500 can be identified.

[0054] The marker 520 is not limited to a helmet band. The marker 520 may be a shape, pattern, or color directly formed on the helmet 510, or a combination thereof.

[0055] The process of detecting a person in the image executed in step S110 is not limited to the above-described one. For example, a person in the image may be detected by extracting feature points of a face or a skeleton from the image. For example, the person detection unit 310 can detect a person in the image based on feature points of the face such as the size, direction, relative position, or relative distance of eyes, nose, or mouth, which are parts constituting the face. Also, the person detection unit 310 can detect a person in the image based on features of the skeleton such as the length, direction, relative position, or relative distance of shoulders, elbows, or knees, which are parts constituting the body. Note that the feature points of the face or the skeleton can be extracted by applying a learning model learned by, for example, machine learning or deep learning (including a convolutional neural network).

[0056] When a person corresponding to the worker 500 is detected in the image (step S110: YES), step S120 is executed. Also, when a person corresponding to the worker 500 is not detected in the image (step S110: NO), the monitoring process ends. In this case, the monitoring process is started using another image transmitted from the imaging device 200.

[0057] In step S120, the height calculation unit 320 calculates the height of the working position of the worker 500 performing the work at height. As shown in FIG. 5, the worker 500 may perform the work at height while riding in the bucket of the aerial work vehicle 600. In this case, the height calculation unit 320 detects an object corresponding to the aerial work vehicle 600 from the image, and calculates the height of the working position of the worker 500 based on the size or length of the object.

[0058] The object detected in the image is not limited to the aerial work vehicle 600. The object detected in the image may be, for example, a building or the like. Also in this case, the height calculation unit 320 can calculate the height of the working position of the worker 500 based on the size or height of the building. Note that the height calculated by the height calculation unit 320 does not necessarily have to be an exact value, and an approximate value is sufficient. Even if the height calculated by the height calculation unit 320 is an approximate value, it is possible to prompt the worker 500 performing the aerial work to pay attention to the proper use of the fall arrest device 100, and thus it is possible to prevent disasters in aerial work.

[0059] In step S130, the aerial work determination unit 330 determines whether the work of the worker 500 is aerial work based on the height calculated by the height calculation unit 320. Specifically, the aerial work determination unit 330 determines whether the calculated height is equal to or greater than a predetermined threshold value. If the calculated height is equal to or greater than the predetermined threshold value, it is determined as aerial work. The predetermined threshold value is set based on the content of the aerial work or the type of the fall arrest device 100 to be worn, and is, for example, 2 (m) or 5 (m). When the calculated height is equal to or greater than the threshold value (step S130: YES), step S140 is executed. Also, when the calculated height is less than the threshold value (step S130: NO), the monitoring process ends. In this case, the monitoring process is started using another image transmitted from the imaging device 200.

[0060] In step S140, the aerial work determination unit 330 generates a first signal for operating the RFID reader 162. The first signal is transmitted to the control device 160 of the fall arrest device 100 worn by the worker 500 via the communication unit 350.

[0061] In step S150, the control unit 161 activates the RFID reader 162 based on the first signal. As a result, the RFID reader 162 starts reading the RFID tag 150. When the RFID tag 150 is located within the range where it can communicate with the RFID reader 162, the RFID reader can obtain the identification information of the RFID tag 150.

[0062] In step S160, the control unit 161 determines whether the identification information of the RFID tag 150 has been obtained. As shown in FIG. 6(A), when the worker 500 hangs the hook 130 on a structure 610 such as a handrail or a main rope and properly uses the fall arrest device 100, the RFID tag 150 is located outside the range where it can communicate with the RFID reader 162. Therefore, the RFID reader 162 cannot obtain the identification information of the RFID tag 150. On the other hand, as shown in FIG. 6(B), when the worker 500 uses the fall arrest device 100 with the hook 130 hooked to the hook holder 140, the RFID tag 150 is located within the range where it can communicate with the RFID reader 162. Therefore, the RFID reader 162 can obtain the identification information of the RFID tag 150. Therefore, when the identification information of the RFID tag 150 is obtained (step S160: YES), step S170 is executed. Also, when the identification information of the RFID tag 150 is not obtained, that is, when the identification information of the RFID 150 is not obtained within a predetermined time from the start of the operation of the RFID reader 162 (step S160: NO), the monitoring process ends. In this case, the monitoring process is started using another image transmitted from the imaging device 200.

[0063] In step S170, the control unit 161 generates a second signal including information regarding the unsafe behavior of the worker 500. The second signal is transmitted to the information processing device 300 via the communication unit 164.

[0064] In step S180, the control unit 161 activates the sound output unit 163 based on the second signal. As a result, the sound output unit 163 can output a warning sound regarding the proper use of the fall prevention device 100, and prompt the operator 500 to pay attention to the proper use of the fall prevention device 100. Note that the warning sound can be stopped when the identification information of the RFID tag 150 cannot be acquired. Alternatively, the RFID reader 162 may be provided with a switch for stopping the warning sound.

[0065] In step S190, the unsafe behavior information generation unit 340 generates unsafe behavior information based on the second signal. The generated unsafe behavior information may be stored in the information processing device 300 or transmitted to the information terminal 400. When the unsafe behavior information is transmitted to the information terminal 400 of the supervisor at the work site, the supervisor can know that the operator 500 may not be using the fall prevention device 100 properly. Therefore, in order to obtain the detailed working state of the operator 500, the supervisor can also receive an image of the work site taken by the imaging device 200 using the information terminal 400.

[0066] When step S190 is executed, the monitoring process ends.

[0067] As described above, according to the safety monitoring system 10 according to an embodiment of the present invention, based on an image of the work site, it is determined whether the operator 500 is performing high-altitude work. When the operator 500 is performing high-altitude work, it can be determined whether the operator 500 is using the fall prevention device 100 properly. Therefore, the safety monitoring system 10 can alert the operator 500 performing high-altitude work about safety, and prevent disasters such as the operator falling during high-altitude work. Further, the fall prevention device 100 according to an embodiment of the present invention has a simple structure, so it has high versatility and excellent productivity.

[0068] As long as the embodiments described above as embodiments of the present invention do not conflict with each other, they can be implemented in appropriate combinations. In addition, based on each embodiment, those in which those skilled in the art have appropriately added, deleted, or changed the design of components, or added, omitted, or changed the conditions of processes, as long as they have the gist of the present invention, they are included in the scope of the present invention.

[0069] Even for other operational effects different from those brought about by the above-described embodiments, those that are obvious from the description of this specification or can be easily predicted by those skilled in the art are naturally understood to be brought about by the present invention.

Explanation of Reference Numerals

[0070] 10: Safety monitoring system, 100: Fall prevention device, 110: Shoulder belt, 111: Chest belt, 112: Waist belt, 113: Leg belt, 120: Rope, 130: Hook, 140: Hook holder, 150: RFID tag, 160: Control device, 161: Control unit, 162: RFID reader, 163: Sound output unit, 164: Communication unit, 200: Imaging device, 210: Imaging unit, 220: Communication unit, 300: Information processing device, 310: Person detection unit, 320: Height calculation unit, 330: High-altitude work determination unit, 340: Unsafe behavior information generation unit, 350: Communication unit, 400: Information terminal, 500: Worker, 510: Helmet, 520: Marker, 600: High-altitude work vehicle, 610: Structure

Claims

1. An imaging device for photographing a work site, A fall prevention device worn by an operator at the work site, An information processing device communicably connected to the imaging device and the fall prevention device, The fall prevention device, A wireless tag attached to a hook of a lanyard connected to a belt worn by the operator, A wireless reader included in a control device provided on the belt and capable of reading the wireless tag, The information processing device, A person detection unit that detects a person corresponding to the operator from the photographed image, A height calculation unit that calculates the height of the operator's work position based on the image, A high-place work determination unit that determines whether the height is equal to or greater than a predetermined threshold value, When the height is equal to or greater than the predetermined threshold value, the high-place work determination unit generates a first signal for operating the wireless reader. A safety monitoring system.

2. The safety monitoring system according to claim 1, wherein when the belt is worn by the operator and the hook is hooked on a hook holder provided on the belt, the wireless reader is located within 30 cm from the wireless tag.

3. The fall prevention device further includes a control unit in the control device for controlling the wireless reader based on the first signal, The control unit generates a second signal to be transmitted to the information processing device when the wireless reader acquires identification information of the wireless tag. The safety monitoring system according to claim 1.

4. The fall prevention device further includes a sound output unit that outputs a warning sound when the second signal is generated. The safety monitoring system according to claim 3.

5. The information processing apparatus further includes an unsafe behavior information generation unit that generates unsafe behavior information to be transmitted to a predetermined information terminal based on the second signal, for the safety monitoring system according to claim 3 or claim 4.

6. The person detection unit detects the person in the image based on a marker attached to a helmet worn by the worker, for the safety monitoring system according to any one of claims 1 to 5.

7. The first signal is transmitted to the fall prevention device including the wireless reader associated with the marker, for the safety monitoring system according to claim 6.

8. The height calculation unit calculates the height based on an object detected in the image, for the safety monitoring system according to any one of claims 1 to 7.

Images