Portable Work Platform and Safety Monitoring System

Abstract

To provide a portable worktable that can be recognized by an image.SOLUTION: A portable worktable includes a pair of ladder-shaped support legs, a top plate that is suspended between the pair of ladder-shaped support legs, and a lowered swing that is suspended from the center of the underside of the top plate. The swing includes a weight and a string-like member that holds the weight. The weight may include a specified marker. The weight may include a circular top surface perpendicular to the string-like member. The weight may include a side surface, and the specified marker may include a first marker on the top surface and a second marker on the side surface. The first marker may be different from the second marker.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] One embodiment of the present invention relates to a safety monitoring system that monitors the safety of a work site using a portable work platform. Another embodiment of the present invention relates to a portable work platform used in the safety monitoring system. [Background technology]

[0002] Various devices and equipment are used at work sites, and it is important that these devices and equipment are used correctly to ensure safe work. For example, portable work platforms (also called stand-up platforms) are primarily used for low-to-medium-level work, and workers often work without wearing safety harnesses (also called fall arrest devices). Therefore, if the portable work platform is not installed level, accidents such as the portable work platform tipping over or the worker falling may occur. For example, Patent Document 1 discloses a method for preventing workers from falling from a portable work platform, in which the load pattern of the worker on the top surface of the portable work platform is detected and a warning is issued to the worker. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-4513 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if a portable work platform is not being used correctly, even if workers are warned, they will still be working in a dangerous condition. Therefore, there is a need for a third party to monitor whether portable work platforms are being used correctly at the work site.

[0005] In view of the above problems, one object of one embodiment of the present invention is to provide a portable work platform that can be recognized by an image. Another object of one embodiment of the present invention is to provide a safety monitoring system that monitors whether the portable work platform is being used correctly and safely. [Means for solving the problem]

[0006] A portable workbench according to one embodiment of the present invention includes a pair of ladder-shaped support legs, a top plate suspended between the pair of ladder-shaped support legs, and a plumb bob suspended from the center of the underside of the top plate, the plumb bob including a weight and a string-like member for holding the weight.

[0007] The weight may include a predetermined marker.

[0008] The weight may include a circular upper surface that is perpendicular to the string member.

[0009] The weight includes a side surface, and the predetermined markers include a first marker attached to the top surface and a second marker attached to the side surface, and the first marker may be different from the second marker.

[0010] A safety monitoring system according to one embodiment of the present invention includes a plumb bob identification unit that identifies the plumb bob of a portable work platform in an image based on a predetermined marker included in the image; a top plate identification unit that identifies the top plate of the portable work platform in the image based on the identified plumb bob; a top plate state detection unit that generates a top plate state value that represents the horizontal state of the top plate based on the identified plumb bob and top plate; and a determination unit that determines the levelness of the portable work platform based on the top plate state value.

[0011] The tabletop state detection unit may convert the two-dimensional coordinates of the tabletop into three-dimensional coordinates, and generate the tabletop state value based on the converted three-dimensional coordinates.

[0012] The safety monitoring system further includes a stop fitting status detection unit that generates stop fitting status information that represents the status of the stop fittings of the portable work platform in the image, and the judgment unit may further judge whether the stop fittings of the portable work platform are being used correctly based on the stop fitting status information. [Effects of the Invention]

[0013] The portable work platform according to one embodiment of the present invention is easily identifiable in captured images, making it possible to check the usage status of the portable work platform using the images. Furthermore, the safety monitoring system according to one embodiment of the present invention can use the images to determine whether the portable work platform is being used correctly and safely and issue a warning to the worker. Therefore, accidents such as a worker falling from the portable work platform can be prevented during work using the portable work platform. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram showing the configuration of a safety monitoring system according to an embodiment of the present invention; [Figure 2] 1A and 1B are schematic top and side views of a portable work platform used in a safety monitoring system according to an embodiment of the present invention; [Figure 3] 1 is a schematic perspective view showing the configuration of a plumb bob of a portable work platform used in a safety monitoring system according to one embodiment of the present invention. FIG. [Figure 4] 1 is a block diagram showing the configuration of an imaging device and an information processing device of a safety monitoring system according to an embodiment of the present invention. [Figure 5] 1 is a flowchart illustrating a monitoring process of a work site using a safety monitoring system according to an embodiment of the present invention. [Figure 6] 2 is a schematic diagram illustrating a monitoring process executed by an information processing device of a safety monitoring system according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. Note that the embodiments are merely examples, and any modifications that a person skilled in the art could easily make while maintaining the gist of the invention are naturally included within the scope of the present invention. Furthermore, in order to clarify the explanation, the drawings may show the width, thickness, shape, etc. of each part more schematically than the actual embodiment. However, the shapes shown in the drawings are merely examples and do not limit the interpretation of the present invention.

[0016] In this specification, for convenience of explanation, the terms "above," "upper," or "upper portion," or "below," "below," or "lower portion" are used, but these terms merely describe the hierarchical relationship of each component. For example, when describing the positional relationship of components of a structure, the normal use state of the structure is used as the basis, and the surface side on which the structure is installed (for example, the floor side) may be referred to as "below," "below," or "lower portion."

[0017] In this specification, the letters "first," "second," or "third" attached to each component are convenient labels used to distinguish each component, and have no other meaning unless otherwise specified.

[0018] In this specification and drawings, the same reference numeral is used to collectively represent multiple identical or similar components, and uppercase or lowercase letters may be added to distinguish between the multiple components. Furthermore, a hyphen and a natural number may be used to distinguish between multiple parts of a single component.

[0019] The configuration of a safety monitoring system 10 according to one embodiment of the present invention and the monitoring process of a work site using the safety monitoring system 10 will be described with reference to FIGS. 1 to 6. FIG.

[0020] [1. Configuration of safety monitoring system 10] FIG. 1 is a schematic diagram showing the configuration of a safety monitoring system 10 according to one embodiment of the present invention. The safety monitoring system 10 includes a portable work platform 100, an imaging device 200, and an information processing device 300. The imaging device 200 can capture images of the portable work platform 100 installed at a work site. The imaging device 200 is communicably connected to the information processing device 300, and therefore, images captured by the imaging device 200 are transmitted to the information processing device 300. The information processing device 300 can determine whether the portable work platform 100 is being used correctly based on the captured images. In other words, the safety monitoring system 10 is a system that monitors the safety of a work site where the portable work platform 100 is used.

[0021] [1-1. Configuration of portable workbench 100] First, the configuration of the portable work platform 100 used in the safety monitoring system 10 will be described.

[0022] 2A and 2B are schematic top and side views of a portable work platform 100 used in a safety monitoring system 10 according to an embodiment of the present invention. Specifically, Fig. 2A is a top view of the portable work platform 100, and Figs. 2B and 2C are side views of the portable work platform 100. The portable work platform 100 includes a top plate 110, a pair of support legs 120, a stopper 130, and a plumb bob 140.

[0023] The tabletop 110 has a rectangular shape with two long sides (y direction) and two short sides (x direction). Each of the two short sides of the tabletop 110 is supported by a support leg 120, and the tabletop 110 is spanned between the pair of support legs 120.

[0024] The support leg 120 includes two posts 122 and a plurality of treads 124. The plurality of treads 124 are spanned between the two posts 122. In other words, the support leg 120 has a ladder shape. The width of the two posts 122 increases downward. Therefore, the length of the tread 124 spanned between the two posts 122 is longer on the lower level than on the upper level. The number and spacing of the treads 124 are not particularly limited. The number and spacing of the treads 124 are determined appropriately taking into consideration the stride length of the worker, etc.

[0025] The support 122 may be extendable. For example, the support 122 may include an upper support (outer tube) and a lower support (inner tube), with the lower support inserted into the upper support. In this case, the support 122 can be extended by pulling the lower support out from the upper support.

[0026] The support legs 120 can be folded toward the bottom of the top plate 110. At the work site, the folded support legs 120 are unfolded, and the positions of the top plate 110 and the support legs 120 are fixed by the opening stopper 130 so that the support legs 120 form a certain angle with respect to the top plate 110. The opening stopper 130 may be provided so as to be bendable, with one end fixed to the top plate 110 and the other end fixed to the support legs 120. In this case, when the portable work platform 100 is used, the opening stopper 130 is used so as to be linear. When the portable work platform 100 is not in use, the opening stopper 130 can be bent to fold the support legs 120 toward the bottom of the top plate 110. Alternatively, opening stopper 130 may have a linear shape, with one end rotatably fixed to one of top plate 110 and support leg 120, and the other end provided so as to be engageable with the other of top plate 110 and support leg 120. In this case, when portable workbench 100 is used, support leg 120 is opened and opening stopper 130 is engaged between top plate 110 and support leg 120. In either case, opening stopper 130 has a linear shape between top plate 110 and support leg 120 when portable workbench 100 is in use.

[0027] The plumb bob 140 includes a weight 142 and a string-like member 144. The plumb bob 140 is suspended from the tabletop 110. Specifically, one end of the string-like member 144 is connected to the top surface of the weight 142, and the other end of the string-like member 144 is connected to the bottom surface of the tabletop 110. The weight 142 is sufficiently heavier than the string-like member 144. Therefore, in the plumb bob 140, the length direction of the string-like member 144 is always vertical. The string-like member 144 is not particularly limited as long as it can hold the weight 142 when the plumb bob 140 is suspended and its length direction points vertically. For example, a thread-like member or a rod-like member can be used instead of the string-like member 144.

[0028] Here, the configuration of the plumb bob 140 will be described with reference to FIG.

[0029] FIG. 3 is a schematic perspective view showing the configuration of the plumb bob 140 of the portable work platform 100 used in the safety monitoring system 10 according to one embodiment of the present invention. The plumb bob 140 has a cylindrical shape including a circular upper surface. The plumb bob 140 may have any shape as long as it includes at least a circular upper surface. For example, the plumb bob 140 may have a conical or truncated conical shape including a circular upper surface. One end of the string-like member 144 is connected to the center of the upper surface of the weight 142, i.e., the center of the circle. However, the connection position of the one end of the string-like member 144 is not limited thereto. The one end of the string-like member 144 may be connected to the weight 142 so that the normal direction to the upper surface of the weight 142 is always parallel to the length direction of the string-like member 144 when the string-like member 144 is pointed vertically. The other end of the string-like member 144 is connected to the center of the bottom surface of the top plate 110, i.e., the intersection of the diagonals of the rectangular shape. However, the position of the other end of the string-like member 144 is not limited to this. For example, the other end of the string-like member 144 may be connected to a corner of the top plate 110 (a vertex of a quadrangle).

[0030] The weight 142 has a predetermined marker. The marker may be a shape, a pattern, a color, or a combination thereof. The marker is preferably one that distinguishes the top surface of the weight 142 from the other surfaces. For example, the marker can be formed by applying a first color to the top surface of the weight 142 and applying a second color different from the first color to the other surfaces. Alternatively, the marker can be formed by providing a first stripe pattern running along a first direction on the top surface of the weight 142 and a second stripe pattern running along a direction different from the first direction on the other surfaces.

[0031] As will be described in more detail below, the portable work platform 100 includes a plumb bob 140, which has a marker, so that the marker can be detected in an image taken of the work site, and the plumb bob and portable work platform can be easily identified in the image.

[0032] 1-2. Configuration of the imaging device 200 and the information processing device 300 Next, the configurations of the imaging device 200 and the information processing device 300 of the safety monitoring system 10 will be described.

[0033] 4 is a block diagram showing the configuration of an imaging device 200 and an information processing device of a safety monitoring system 10 according to an embodiment of the present invention. The imaging device 200 is communicably connected to an information processing device 300 via a network NW. The network NW is preferably wireless, such as the Internet. The imaging device 200 includes an imaging unit 210 and a communication unit 220. The information processing device 300 includes a plumb bob identifying unit 310, a portable workbench identifying unit 320, a top board state detecting unit 330, an opening stop metal state detecting unit 340, a determining unit 350, a communication unit 360, and a memory unit 370.

[0034] The imaging unit 210 can capture images of the work site and generate images. The imaging unit 210 is, for example, a camera including a solid-state imaging element such as a CD (Charge-Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor.

[0035] The communication unit 220 is a communication interface capable of transmitting and receiving information or data, and can transmit images captured by the imaging unit 210 to the information processing device 300.

[0036] The imaging device 200 may be installed at a predetermined position at the work site and capture images of the work site within its angle of view, or may be attached to a worker's helmet or the like and capture images of the work site while moving with the worker. Furthermore, the imaging device 200 may be mounted on a mobile object that can move around the work site, such as a drone or an autonomous robot.

[0037] 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.

[0038] The plumb bob identification unit 310, portable work platform identification unit 320, work top state detection unit 330, opening stopper state detection unit 340, and determination unit 350 can function by a computer executing a program stored in a storage device. The communication unit 360 can receive information or data from the imaging device 200. Specifically, the communication unit 360 can receive images of the work site captured by the imaging device 200. The communication unit 360 can also transmit unsafe behavior information, which will be described later, to the information terminals of workers or supervisors at the work site. The memory unit 370 can store information or data, and a portable work platform database 372 is stored in the memory unit 370. Markers and portable work platforms 100 are associated and registered in the portable work platform database 372. Therefore, the portable workbench database 372 can be used to obtain parameters of the portable workbench 100 linked to the marker (e.g., the three-dimensional coordinates of each vertex of the tabletop 110, the length of the short side and the length of the long side, and the diameter of the top surface of the plumb bob 140, etc.).

[0039] The plumb bob identification unit 310 can identify a marker in the image and identify the plumb bob based on the marker. For example, if the color painted on the top surface of the weight 142 of the plumb bob 140 is a marker, the plumb bob identification unit 310 can identify the marker, i.e., the top surface of the plumb bob, and identify the plumb bob in the image by distinguishing between the area of ​​the marker color and areas of other colors in the image. Note that, as will be described in detail later, it is preferable that the plumb bob identification unit 310 can identify the top surface of the plumb bob.

[0040] The portable work platform identification unit 320 can identify the rectangular shape located above the plumb bob in the image as the work platform. The work platform in the image is identified as a figure that is 180 degrees rotationally symmetrical around the intersection of the diagonals of the rectangular shape. This reduces the amount of calculation required to calculate the horizontal state of the work platform, which is executed by the work platform state detection unit 330.

[0041] The tabletop state detection unit 330 can detect the horizontal state of the tabletop in the image and generate a tabletop state value based on the plumb bob identified by the plumb bob identification unit 310 and the tabletop identified by the portable work platform identification unit 320. This makes it possible to grasp the level of the portable work platform 100 and determine whether the portable work platform 100 is installed and used correctly.

[0042] The stopper status detector 340 can detect the status of the stopper in the image and generate stopper status information, which allows the usage status of the stopper 130 of the portable work platform 100 to be understood and makes it possible to determine whether the stopper 130 is being used correctly.

[0043] The determination unit 350 can determine the horizontal state of the tabletop 110 of the portable work platform 100 based on the tabletop state value. The determination unit 350 can also determine the usage state of the opening stop fittings 130 of the portable work platform 100 based on the opening stop state detection unit. These can determine whether the portable work platform 100 is being used correctly and safely at the work site. The determination unit 350 can also generate unsafe behavior information if the portable work platform 100 is not being used correctly and safely. The unsafe behavior information may be transmitted to an information terminal of a worker or supervisor at the work site. In this case, the worker or supervisor can be notified of an unsafe state of the portable work platform 100 at the work site and a warning can be issued.

[0044] 2. Workplace Monitoring Process Using Safety Monitoring System 10 5 is a flowchart illustrating a monitoring process of a work site using the safety monitoring system 10 according to one embodiment of the present invention. The monitoring process of a work site using the safety monitoring system 10 starts when the work site is photographed by the imaging device 200. The flowchart shown in FIG. 5 explains the monitoring process (steps S110 to S170) executed by the information processing device 300 based on the image transmitted from the imaging device 200.

[0045] In step S110, the plumb bob identification unit 310 identifies a plumb bob in the image. In other words, the plumb bob identification unit 310 determines whether or not a plumb bob is included in the image. Specifically, the plumb bob identification unit 310 identifies a plumb bob marker in the image and identifies the plumb bob based on the marker. When a plumb bob is identified (step S110: YES), step S120 is executed. When a plumb bob is not identified (step S110: NO), step S110 is executed again.

[0046] In step S120, the portable workbench identification unit 320 identifies a portable workbench in the image. In other words, the portable workbench identification unit 320 determines whether or not a portable workbench is included in the image. Specifically, the portable workbench identification unit 320 identifies the rectangular shape located above the identified plumb line as the worktop. If the worktop is identified (step S120: YES), step S130 is executed. If the worktop is not identified (step S120: NO), step S110 is executed again.

[0047] In step S130, the tabletop state detection unit 330 detects the horizontal state of the identified tabletop. Detecting the horizontal state of the tabletop involves converting the two-dimensional coordinates of the tabletop in the image into three-dimensional coordinates, correcting the shooting angle of the image capture device 200, and generating a tabletop state value that compares the vertical direction with the horizontal direction perpendicular to the vertical direction. The following describes the process in order, with reference to FIG. 6 as needed. FIG. 6 is a schematic diagram illustrating the monitoring process executed by the information processing device 300 of the safety monitoring system according to one embodiment of the present invention.

[0048] First, we will explain how to convert the two-dimensional coordinates of the tabletop in the image into three-dimensional coordinates. As shown in Figure 6(A), the image has two-dimensional coordinates (u, v), but if we expand this to three-dimensional coordinates (u, v, w), the image plane can be expressed as three-dimensional coordinates (u, v, 0).

[0049] The tabletop state detection unit 330 acquires the two-dimensional coordinates of the tabletop in the image and expands them to three-dimensional coordinates within the image plane (hereinafter referred to as "first three-dimensional coordinates"). Next, the tabletop state detection unit 330 acquires the three-dimensional coordinates of the tabletop 110 of the portable work table 100 linked to the marker from the portable work table database 372. In reality, these are the three-dimensional coordinates of the four vertices of the tabletop 110, but for convenience, these will be described as the three-dimensional coordinates of the tabletop 110. The tabletop state detection unit 330 generates three-dimensional coordinates (hereinafter referred to as "second three-dimensional coordinates") by reducing, enlarging, or rotating the three-dimensional coordinates of the tabletop 110, and compares the three-dimensional coordinates (hereinafter referred to as "third three-dimensional coordinates") projected onto the image plane with the first three-dimensional coordinates. The tabletop state detection unit 330 repeatedly generates and compares the second three-dimensional coordinates until the third three-dimensional coordinates match the first three-dimensional coordinates (for example, the first three-dimensional coordinates and the third three-dimensional coordinates have a predetermined degree of match or higher). The tabletop state detection unit 330 acquires the second three-dimensional coordinates corresponding to the third three-dimensional coordinates that match the first three-dimensional coordinates as the three-dimensional coordinates (u, v, w) of the tabletop in the image.

[0050] The method for converting the two-dimensional coordinates of the tabletop and plumb bob on the screen into three-dimensional coordinates is not limited to the above method, as long as the plumb bob identification unit 310 and the tabletop state detection unit 330 can acquire the three-dimensional coordinates of the tabletop based on the tabletop and plumb bob identified in the image.

[0051] Next, a conversion for correcting the imaging angle of the imaging device 200 will be described.

[0052] As shown in FIG. 6B, the tabletop state detection unit 330 detects the length d of the minor axis of the top surface of the plumb bob in the image. a and the length of the major axis d b The imaging angle θ of the imaging device 200 with respect to the upper surface of the weight is expressed by equation (1).

[0053]

number

[0054] The tabletop state detection unit 330 also acquires the two-dimensional coordinates of the center of the tabletop and the center of the top surface of the plumb bob in the image. The direction of the line connecting the center of the tabletop and the center of the top surface of the bob corresponds to the vertical direction in the image. The tabletop state detection unit 330 calculates a line (hereinafter referred to as the "center line") that passes through the center of the tabletop and is perpendicular to the vertical direction in the image. The center line represents the horizontal direction in the image. The two-dimensional coordinates of the center line are expanded into three-dimensional coordinates within the image plane, and are expressed as a unit vector (n u ,n v ,0).

[0055] The above description is for the case where the other end of string-like member 144 of plumb bob 140 is connected to the center of tabletop 110. However, even if the other end of string-like member 144 of plumb bob 140 is not at the center of tabletop 110, it is possible to calculate the center line by acquiring the connection position between tabletop 110 and the other end of string-like member 144 in advance.

[0056] The horizontal direction is the direction seen from the side of the weight, and can be obtained by rotating the weight by an angle of -θ around the center line. Then, the second three-dimensional coordinate (u, v, w) is expressed by the unit vector (n u ,n v By performing a transformation that rotates the tabletop by an angle φ (=-θ) around the axis (θ, 0), the three-dimensional coordinates (u', v', w') of the tabletop as viewed from the horizontal direction are obtained. The transformation formula is expressed as formula (2).

[0057]

number

[0058] Next, the generation of the tabletop state value in comparison with the horizontal direction perpendicular to the vertical direction will be described.

[0059] The tabletop state detection unit 330 calculates the distance from the center line of the three-dimensional coordinates (u', v', w') of the tabletop projected onto the image plane, that is, the three-dimensional coordinates (u', v', 0). Because the unit vector of the center line is horizontal, a small distance from the center line indicates a small tilt of the tabletop, and a large distance from the center line indicates a large tilt of the tabletop. In other words, the calculated distance from the center line can be considered a tabletop state value that indicates the horizontal state of the tabletop.

[0060] Step S130 ends with the tabletop status value being generated.

[0061] In step S140, the stopper status detection unit 340 detects the status of the stopper of the portable workbench in the image and generates stopper status information. Specifically, the stopper status detection unit 340 identifies a shape extending from the long side of the tabletop to the support leg or from the support leg toward the long side of the tabletop in the image. The identified shape may be, for example, a straight or curved shape. When the identified shape is a straight shape, the stopper status detection unit 340 generates normal stopper status information. When the identified shape is other than a straight shape, the fixture status detection unit 340 generates abnormal stopper status information. Furthermore, when a shape extending from the long side of the tabletop to the support leg or from the support leg toward the long side of the tabletop is not identified (for example, when the end of the shape does not overlap with the tabletop or the support leg), abnormal stopper status information is generated. That is, when the opening stopper fitting 130 of the portable work platform 100 is not being used normally, opening stopper fitting status information indicating an abnormal state is generated.

[0062] In step S150, the determination unit 350 determines the horizontal state of the tabletop 110 of the portable work platform 100 based on the tabletop state value. If the tabletop state value is equal to or less than a predetermined threshold value (step S150: YES), step S160 is executed. If the tabletop state value exceeds the predetermined threshold value (step S150: NO), step S170 is executed.

[0063] In step S160, the determination unit 350 determines the usage status of the stop fittings 130 of the portable work platform 100 based on the stop fitting status information. If the stop fitting status information is normal (step S160: YES), the monitoring process ends. If the stop fitting status information is abnormal (step S160: NO), step S170 is executed.

[0064] In step S170, the determination unit 350 generates unsafe behavior information. The unsafe behavior information is information that indicates that the portable work platform 100 is not being used in a safe state. When step S170 is executed, the monitoring process ends. It is preferable that the monitoring process be performed periodically, and preferably intermittently at a fixed cycle. By performing the monitoring process periodically, safety can be ensured at work sites where the work process changes significantly (for example, construction sites, etc.).

[0065] Although detailed explanation is omitted, the generated unsafe behavior information can be sent to the information terminal of the worker or supervisor at the work site, thereby notifying the worker or supervisor of the unsafe condition of the portable workbench 100 at the work site and issuing a warning.

[0066] As described above, the safety monitoring system 10 according to one embodiment of the present invention can determine whether the portable work platform 100 is being used correctly and safely based on an image captured of a work site where the portable work platform 100 is used. Therefore, the safety monitoring system 10 can monitor the safety of a work site where the portable work platform 100 is used. Furthermore, the portable work platform 100 according to one embodiment of the present invention has a predetermined marker attached to the weight 142, so that the marker can be detected in an image, and the top plate and plumb bob can be easily identified in the image.

[0067] The above-described embodiments of the present invention may be combined as appropriate as long as they are not mutually inconsistent. Furthermore, even if a person skilled in the art appropriately adds or deletes components or modifies designs, or adds or omits processes or modifies conditions based on the embodiments, such combinations are included within the scope of the present invention as long as they include the gist of the present invention.

[0068] Even if there are other effects and advantages different from those brought about by the above-mentioned embodiments, those that are clear from the description in this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0069] 10: Safety monitoring system, 100: Portable work platform, 110: Top plate, 120: Support leg, 122: Support pole, 124: Step bar, 130: Metal fitting, 142: Weight, 144: String-like member, 200: Imaging device, 210: Imaging unit, 220: Communication unit, 300: Information processing device, 310: Identification unit, 320: Portable work platform identification unit, 330: Top plate state detection unit, 340: Metal fitting state detection unit, 350: Determination unit, 360: Communication unit, 370: Storage unit, 372: Portable work platform database

Claims

1. A pair of ladder-shaped support legs; a top plate spanning the pair of ladder-shaped support legs; a plumb bob suspended from the center of the underside of the top plate; The plumb bob is a weight including a top surface and a side surface; a string-like member for holding the weight, the upper surface has a circular shape perpendicular to the string-like member, the weight includes a predetermined marker; the predetermined markers include a first marker attached to the top surface and a second marker attached to the side surface; The portable work platform, wherein the first marker is different from the second marker.

2. a plumb bob identifier that identifies a plumb bob of a portable work platform in an image based on a predetermined marker included in the image; a top plate identifying unit that identifies the top plate of the portable work platform in the image based on the identified plumb bob; a tabletop state detection unit that generates a tabletop state value that indicates a horizontal state of the tabletop based on the identified plumb bob and the tabletop; a determination unit that determines the levelness of the portable work platform based on the tabletop status value.

3. The safety monitoring system according to claim 2 , wherein the tabletop state detection unit converts two-dimensional coordinates of the tabletop into three-dimensional coordinates, and generates the tabletop state value based on the converted three-dimensional coordinates.

4. Further, a stop fitting state detection unit is provided for generating stop fitting state information representing a state of the stop fitting of the portable work platform in the image, 4. The safety monitoring system according to claim 2, wherein the determining unit further determines whether the stop fittings of the portable work platform are being used correctly based on the stop fitting status information.

Images