Device for inspecting an underground pipe network from a manhole and associated method

Abstract

Inspection device for an underground pipe network from a manhole and associated method. The device (10) comprises a positioning system (24) and a longitudinal guide rod (26) designed to extend along the central axis of a manhole (20) for insertion into the manhole (20). The device (10) includes an inspection unit (30) designed to be engaged on the guide rod (26), the inspection unit (30) being movable relative to the positioning system (24) at least along the central axis, the inspection unit (30) comprising: at least one camera, and a projection system configured to project a specific pattern defining at least a characteristic distance onto an internal surface of the manhole, the specific pattern being designed to be positioned in an area visible to at least one camera.The device (10) includes a measuring system (28) configured to measure the height at which the inspection unit (30) is positioned along the central axis. Figure for the abbreviation: Figure 2.

Description

Title of the invention: Device for inspecting an underground pipe network from a manhole and associated method

[0001] The present invention relates to a device for inspecting a network of underground pipes, the network comprising a manhole, the manhole extending around a central axis.

[0002] Such a device is used to inspect a network of underground pipes, in particular to determine specific measurements of the network, in particular depths, inclinations, diameters, orientations of pipes accessible from the manhole and / or opening into it, or to take photos or videos inside the pipes.

[0003] The underground pipe network is, for example, a wastewater and / or stormwater drainage network.

[0004] To perform various maintenance and inspection operations, an underground pipeline network includes manholes for inspection and operation. A manhole is an opening drilled vertically between the surface and pipelines of the network, which open into the manhole. The manhole thus allows access to certain areas of the network and / or the connection of dwelling(s) to a sewer main. The inspection device mentioned above is designed to be inserted into a manhole of the network being inspected.

[0005] Determining specific measurements of an underground pipeline network makes it possible, in particular, to precisely position and map the underground pipelines and thus avoid potential damage caused, for example, during work carried out in the vicinity of said network. These measurements also improve the knowledge of the network's infrastructure.

[0006] Regulations in some countries are evolving. For example, in France, regulations will require project owners to provide network plans in class A, i.e. with an accuracy of 40 cm, in 2026 for urban areas and in 2032 for rural areas.

[0007] Typically, specific measurements are determined by measurement campaigns carried out by a surface operator who inserts a measuring system into a manhole of the inspected network. The measuring system is, for example, a tape measure that the operator unrolls from outside the manhole and on which they read a height between the manhole surface and a measurement point. From these measurements, calculations may be performed to determine the desired specific measurements.

[0008] However, such a method is not entirely satisfactory. On the one hand, the uncertainty of the measurements is high, the measurement error coming mainly from the accuracy of the measurement system used and of the determination of measurement points by the operator from the surface.

[0009] On the other hand, in order to ensure that the measuring system has actually reached the desired measuring point, the operator is often obliged to lean over the eye and therefore risks falling into the eye.

[0010] One object of the invention is to propose an inspection device that allows for the very precise determination of characteristic measurements of an underground pipe network, while maximizing ergonomics and safety for the operator.

[0011] To this end, the invention relates to a device for inspecting a network of underground pipes comprising a manhole, the manhole extending around a central axis, the device being characterized by:

[0012] - a positioning system intended to be disposed outside and above the glance ;

[0013] - a longitudinal guide rod intended to extend along the central axis, the rod being intended to be inserted into the manhole and mounted on the positioning system, and;

[0014] - an inspection unit intended to be engaged on the guide rod, the unit The inspection unit being mobile relative to the positioning system at least along the central axis, the inspection unit comprising:

[0015] - at least one camera, and;

[0016] - a projection system configured to project a specific pattern defining at least one characteristic distance on an internal surface of the gaze, the specific pattern being intended to be positioned in an area visible to at least one camera;

[0017] - a measuring system configured to measure the height at which is positioned the inspection unit along the central axis.

[0018] According to other advantageous aspects of the invention, the device comprises one or more of the following features, taken individually or in all technically possible combinations:

[0019] - the guide rod is intended to be engaged on the positioning system;

[0020] - the inspection unit is mounted to move in translation on the rod along the axis central;

[0021] - the guide rod comprises a plurality of tubes assembled end to end;

[0022] - the processing unit includes an input module configured to acquire input data entered by an operator via a human-machine interface;

[0023] - the device includes a coordinate determination system geographical features of the inspection unit, particularly by satellite;

[0024] - the device includes a battery configured to electrically power the unit inspection;

[0025] - the guide rod is mounted to rotate relative to the positioning system around the central axis, the inspection unit being movable jointly in rotation around the central axis with the guide rod, the device advantageously comprising an angular measurement system configured to determine the angle of rotation of the inspection unit with respect to the positioning system;

[0026] - the inspection unit further comprises at least one light source intended to illuminate the area visible to at least one camera;

[0027] - the projection system includes at least one laser configured to project the specific pattern defining at least one characteristic distance on an internal surface of the gaze;

[0028] - the specific motif comprises at least two parallel segments between them on the inner surface of the gaze;

[0029] - it comprises a processing unit, the processing unit comprising:

[0030] - an acquisition module configured to acquire the data recorded by the minus one camera, and

[0031] - a screen, the screen being configured to display data recorded by the minus one camera including the specific pattern;

[0032] - the processing unit includes a processing module configured to determine from the acquired data and the characteristic distance, at least one representative measurement of the sight and / or a defined region present in the sight, in particular of a pipe opening into the sight, the screen being advantageously configured to display at least one representative measurement determined by the processing module;

[0033] - the processing module is configured to determine from the data acquired and the characteristic distance, information representative of a fouling rate of a pipe opening into the inspection chamber;

[0034] - the inspection unit comprises a first camera and a second camera, the the first camera being configured to capture images in the near field and the second camera being configured to capture images in the further field inside the pipes opening into the manhole;

[0035] - the inspection unit includes a lower region equipped with a system amortization.

[0036] The invention also relates to a method for inspecting a network of underground pipes comprising a manhole, the manhole extending around a central axis, the method comprising the following steps:

[0037] - supply of an inspection device as defined above;

[0038] - installation of the positioning system;

[0039] - arrangement of the guide rod in the manhole along the central axis, and descent of the inspection unit along the central axis jointly with the guide rod or along the guide rod;

[0040] - projection by the projection system of the specific pattern onto an internal surface in the gaze,

[0041] - taking at least one image of the internal surface of the gaze on which appears the specific pattern using at least one camera.

[0042] According to other advantageous aspects of the invention, the method comprises one or more of the following features, taken individually or in all technically possible combinations:

[0043] - the gaze includes a movable buffer between a gaze closure position and an open gaze position, the step of arranging the guide rod being preceded by a step of placing the buffer in the open gaze position and the step of taking at least one image being followed by the following steps:

[0044] - removal of the guide rod from the sight glass, either jointly with or after the unit has been raised inspection along the central axis,

[0045] - passage of the buffer into the position of closing the gaze;

[0046] - it includes a preliminary step to the projection of the specific pattern, in which at least one camera is activated when the inspection unit is positioned in relation to the internal surface;

[0047] - the acquisition of at least one image is followed by a step of determining at least a representative measure of the gaze and / or a defined region present in the gaze, in particular of a conduit opening into the gaze, from the characteristic distance of the specific pattern.

[0048] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0049] [Fig-1] [Fig.1] is a schematic cross-sectional view of a manhole in which a The inspection device according to the invention is intended to be introduced,

[0050] [Fig.2] [Fig.2] is a partial perspective view of an inspection device according to the invention, positioned above the eye,

[0051] [Fig.3] [Fig.3] is a partial perspective view of the inspection unit of the device of the [Fig.2],

[0052] [Fig.4] [Fig.4] is a schematic view of a processing unit of the device the [Fig.2],

[0053] [Fig.5] [Fig.6] Figures 5 and 6 are photographs taken by a camera the inspection unit of the [Fig.3].

[0054] Figures 2 to 4 illustrate an example of an inspection device 10 according to the invention, used to inspect a network 12 of underground pipes 16, 18.

[0055] Network 12 is, for example, a wastewater network. It is advantageously a combined sewer system, that is, configured to carry both wastewater and stormwater. Alternatively, network 12 is a separate sewer system; in this case, network 12 is either a wastewater network or a stormwater network.

[0056] Preferably, the network 12 comprises a plurality of underground conduits 16, 18.

[0057] In particular, the network 12 includes at least one main conduit 16 as well called "collector" and secondary pipes 18.

[0058] The main pipe 16 discharges, for example, into a wastewater treatment plant in the case of a wastewater or mixed sewage system, or into a stormwater retention basin in the case of a stormwater system. The secondary pipes 18 allow, for example, the connection between a dwelling and the collector.

[0059] For example, the diameter of the main pipe 16 is greater than 100 mm and is generally between 200 mm and 300 mm.

[0060] The diameter of each secondary pipe 18 is smaller than that of the main pipe. It is generally between 60 mm and 200 mm.

[0061] Preferably, the network 12 is a gravity network. In other words, the driving force behind the flow of water in the pipes 16, 18 of the network 12 is gravity. The pipes 16, 18 are then slightly inclined with respect to the horizontal.

[0062] The network 12 further comprises at least one inspection and operating manhole 20 separating the main conduit 18 into a plurality of sections. The manhole 20 will now be described, with reference to [Fig. 1].

[0063] The manhole 20 is an opening cut between the outer surface 21 and the main pipe 16. It generally extends vertically around a central axis. The outer surface 21 is, for example, the roadway or the sidewalk of a street.

[0064] Advantageously, the depth of sight 20 is between 1.5 m and 5 m.

[0065] The eye 20 generally has a round or curved cross-section quadrilateral shape, especially square.

[0066] The eye 20 allows access to the network 12.

[0067] At least one pipe 16, 18 of network 12 opens into the manhole 20.

[0068] In the example of [Fig. 1], the manhole 20 extends vertically to the main pipe 16, which then passes through the manhole 20 at its bottom (also called the "base"). A secondary pipe 18 opens into the manhole 20 above the main pipe 16; the secondary pipe 18 is called the "fall pipe".

[0069] The eye 20 includes a buffer 22, movable between a closed position of the eye 20 and an open position of the eye 20.

[0070] In the closed position of the manhole 20, the plug 22 covers the orifice forming the manhole 20 and is positioned at the level of the outer surface 21. In the open position of the manhole 20, the plug 22 releases the orifice to allow intervention in at least one pipe 16, 18 in particular with the help of the inspection device 10 according to the invention.

[0071] The inspection device 10 is configured to determine the coordinates of characteristic points of the manhole 20 and / or of the pipes 16, 18 opening into the manhole 20, for example points PO, PO', PI, PI', P2, P2', P3, and P3' shown in [Fig.1].

[0072] In the example of [Fig. 1], points PO and PO' are defined to calculate the depth Z0 of the manhole 20 along the central axis. In particular, point PO corresponds to the intersection between the central axis and the outer surface 21, and point PO' corresponds to the intersection between the central axis and the bottom of the manhole 20. Points PI, PI', P2, P2', P3, and P3' characterize the pipes 16, 18 opening into the manhole 20. For example, points PI and PI' are defined to calculate the upstream diameter DI of the main pipe 16, points P2 and P2' to calculate the downstream diameter D2 of the main pipe 16, and points P3 and P3' to calculate the diameter D3 of the secondary pipe 18, at the manhole 20.

[0073] Here and thereafter, the terms "downstream" and "upstream" are understood to mean the flow of water in the main conduit 16.

[0074] The inspection device 10 is used when the plug 22 is in the open position of the manhole 20.

[0075] With reference to [Fig.2], the inspection device 10 comprises a positioning system 24, placed on the ground around the entrance of the manhole 20, a guide rod 26 inserted vertically into the manhole 20, an inspection unit 30 deployable along the guide rod 26 and a measuring system 28 configured to deploy the inspection unit 30 along the guide rod 26 and measure the height of the inspection unit 30.

[0076] The inspection device 10 further includes a battery and a surface processing unit 32.

[0077] Alternatively, the inspection device 10 also includes a system for determining the geographic coordinates of the inspection unit 30, in particular by satellite. The geographic coordinate determination system makes it possible, in particular, to locate the geographic position of the inspected eyepiece 20.

[0078] The positioning system 24 is intended to be disposed outside and above the manhole 20.

[0079] The positioning system 24 includes at least one positioning member 34 and an engagement mechanism 36 for the guide rod 26.

[0080] Following the example of [Fig. 2], the positioning system 24 comprises a tripod. The positioning elements 34 are then three legs deployable from the Engagement mechanism 36 between a folded and deployed position. In the deployed position, the legs are positioned resting on the surface near the eye 20. The legs are, for example, adjustable in length.

[0081] The positioning members 34 are configured to center the engagement mechanism 36 on the central axis of the sight 20.

[0082] Alternatively, the positioning system 24 further includes a fall arrest device. The fall arrest device is, for example, a grid or net extending between the positioning elements 34 and covering the sight 20 to limit the risk of the operator falling.

[0083] The engagement mechanism 36 includes a support 38 and a rotary guide 40 for the guide rod 26.

[0084] The rotary guide 40 is configured to be aligned with the central axis of the sight 20 or parallel to it.

[0085] The rotary guide 40 is rotatably mounted on the support 38 about the central axis. The rotary guide 40 is, for example, connected to the support 38 by a pivot joint. The pivot joint is, for example, achieved by a ball bearing.

[0086] Advantageously, the engagement mechanism 36 includes an angular measurement system configured to determine the angle of rotation of the rotary guide 40 relative to the support 38. The angle determined corresponds, for example, to the angle between an orientation of the rotary guide 40 and a reference orientation, for example, geographic or magnetic North.

[0087] The guide rod 26 is longitudinal and extends along the central axis of the manhole 20. The guide rod 26 is inserted vertically into the manhole 20.

[0088] The guide rod 26 is engaged in the rotary guide 40. Thus, the guide rod 26 is mounted to rotate relative to the positioning system 24 around the central axis by means of the rotary guide 40. The guide rod 26 is also guided in translation along a vertical axis by the rotary guide 40.

[0089] In the example shown in [Fig.2], the guide rod 26 comprises a plurality of tubes 41 assembled end to end until reaching the bottom of the manhole 20. For this purpose, each tube 41 comprises at one end, a fixing mechanism configured to receive the opposite end of the following tube 41.

[0090] The measuring system 28 is fixed at least at one point to the guide rod 26 and extends along the guide rod 26 at least between the support 40 and the inspection unit 30 engaged on the rod 26.

[0091] The measuring system 28 is configured to measure a height along the central axis. In particular, the measuring system 28 is configured to measure the height of the inspection unit 30 along the central axis.

[0092] For example, the measuring system 28 is fixed to the inspection unit 30 and takes the inspection unit 30 as its origin. The height of the inspection unit 30 then corresponds to the distance between the support 40 and the inspection unit 30 along the central axis of the manhole 20. The measuring system 28 therefore makes it possible to determine at what depth the inspection unit 30 is located in the manhole 20.

[0093] For example, the measuring system 28 is graduated and the reading of the graduation is accessible from the outer surface 21.

[0094] According to one embodiment, the measuring system 28 comprises a retractable measuring tape. For this purpose, the measuring system 28 comprises, for example, a reel 42 and a crank 44. Rotation of the crank 44 in a first direction allows the measuring tape to be unrolled along the guide rod 26 and simultaneously lowers the inspection unit 30; rotation of the crank 44 in a second direction, opposite to the first, allows the measuring tape to be wound around the reel 42 and simultaneously raises the inspection unit 30.

[0095] With reference to [Fig.3], the inspection unit 30 comprises a front half-shell 46 and a rear half-shell 48.

[0096] The front half-shell 46 and the rear half-shell 48 are slidably engaged around the guide rod 26. Thus, the inspection unit 30 is translationally mobile relative to the rod 26 along the central axis.

[0097] With reference to [Fig.3], the inspection unit 30 comprises at least one camera 50A, 50B and a projection system 52.

[0098] Following the example of [Fig.3], the inspection unit 30 further comprises at least one light source 54A, 54B.

[0099] Advantageously, the inspection unit 30 includes a lower region equipped with a damping system. The damping system is configured to limit damage to the inspection unit 30 in the event of a fall along the guide rod 26 or upon contact with the bottom of the manhole 20.

[0100] In [Fig.3], the inspection unit 30 comprises a first camera 50A and a second camera 50B.

[0101] Each camera 50A, 50B is here fixed to the front half-shell 46 and arranged so as to take images of an internal surface 56 of the eye 20.

[0102] Preferably, each camera 50A, 50B is configured to take color digital images of the internal surface 56, and if necessary, videos.

[0103] For example, the first camera 50A is configured to capture images in the near field and the second camera 50B is configured to capture images in the further field from inside the pipes 16, 18 opening into the manhole 20.

[0104] The projection system 52 is configured to project a specific pattern 58 defining at least a characteristic distance d onto the internal surface 56 of the eye 20, the pattern 58 being visible by at least one camera 50A, 50B.

[0105] In [Fig.3], the projection system 52 is fixed to the front half-hull 46.

[0106] For example, the specific motif 58 comprises at least two parallel segments 60 on the internal surface 56. In this case, the characteristic distance d corresponds to the distance between two segments 60. The characteristic distance d is preferably measured perpendicular to the two said segments 60.

[0107] In the case where the specific motif 58 comprises at least three segments 60, the distance between two successive segments 60 is preferably constant from one segment 60 to the other and is equal to the characteristic distance d.

[0108] In this example, when the inspection unit 30 is held vertically on the guide rod 26, the two segments 60 extend horizontally.

[0109] For example, the projection system 52 includes at least one laser 62 configured to project the specific pattern 58.

[0110] Following the example of [Fig. 3], the projection system 52 comprises a plurality of lasers 62, each laser 62 being configured to project a beam 63 forming a segment 60 onto the internal surface 56, the segments 60 being parallel to each other. To this end, each laser 62 is arranged opposite a Powell lens which is configured to diffract the laser beam 63 into a straight planar region with a homogeneous power distribution along the line.

[0111] Thus, the beams 63 projected by each laser 62 are parallel to each other and are separated from each other by the characteristic distance d which is equal to the known distance separating the lasers 62.

[0112] On the particular example of [Fig.3], the projection system 52 comprises five 62 lasers, designed to project five parallel straight line segments, each separated by the characteristic distance d. Thus, the probability that two successive parallel straight line segments can be seen on a picture taken by one of the cameras 50A, 50B is maximized.

[0113] Each light source 54A, 54B is intended to illuminate the area visible by at least one camera 50A, 50B.

[0114] Each light source 54A, 54B is for example a light-emitting diode (or "LED", from the English Light Emitting Diodes).

[0115] Each light source 54A, 54B is here fixed to the front half-shell 46.

[0116] Following the example of [Fig.3], the inspection unit 30 comprises two light sources 54B intended to illuminate a distant field and framing the second camera 50B and a light source 54A intended to illuminate in the near field and arranged above the first camera 50A.

[0117] The battery (not visible) is configured to electrically power the inspection unit 30.

[0118] In particular, the battery is configured to power each camera 50A, 50B, the projection system 52 and each light source 54A, 54B, and advantageously the processing unit 32.

[0119] Preferably, the battery is configured to allow the device 10 to be used for one day.

[0120] For example, the battery is located in the inspection unit 30.

[0121] The processing unit 32 is configured to interact with the inspection unit 30.

[0122] The processing unit 32 includes a computer 64 and advantageously, a human-machine interface 66.

[0123] According to one embodiment, the computer 64 and the human-machine interface 66 are remote and communicate with the inspection unit 30 via a wireless transmission link. For example, the inspection unit 30 includes an embedded system communicating via WiFi with the processing unit 32. For example, the inspection unit 30 includes a Raspberry Pi® processor.

[0124] Following the example of [Fig.2], the processing unit 32 is formed by a portable electronic device, in particular by a tablet 68 or alternatively by a mobile phone or a laptop computer.

[0125] Advantageously, the inspection device 10 further includes a console (not shown) intended to receive the tablet 68. The console is for example engaged on the guide rod 26 and movable in rotation around the rod 26.

[0126] Alternatively, the computer 64 is carried by the inspection unit 30 equipped with an embedded system and the human-machine interface 66 is located remotely from the inspection unit 30.

[0127] The computer 64 is configured to implement an acquisition module 70 configured to acquire data recorded by at least one camera 50A, 50B, an input module 72 configured to acquire input data entered by an operator via the human-machine interface 66, and a processing module 74 configured to determine at least one representative measurement of the manhole 20 and / or of a defined region present in the manhole 20, in particular of a pipe 16, 18 opening into the manhole 20, from the data received from the acquisition module 70 and optionally, from the input module 72.

[0128] The calculator 64 includes, for example, at least one memory 76 and at least one processor 78 associated with the memory 76.

[0129] The acquisition module 70, the input module 72 and the processing module 74 are then implemented in the form of one or more software programs, or a software component, executable by processor 78. Memory 76 is then configured to store each software and processor 78 is configured to execute each software.

[0130] In an alternative not shown, the acquisition module 70, the input module 72 and the processing module 74 are made in the form of a programmable logic component, such as an FPGA (Field Programmable Gate Array) or in the form of a dedicated integrated circuit, such as an ASIC (Application Specified Integrated Circuit).

[0131] When the acquisition module 70, the input module 72, and the processing module 74 are implemented as one or more software programs, i.e., as a computer program, it is also capable of being stored on a computer-readable medium (not shown). A computer-readable medium is, for example, a medium capable of storing electronic instructions and being connected to a bus of a computer system. For example, a readable medium is an optical disc, a magneto-optical disc, a ROM, a RAM, any type of non-volatile memory (e.g., EPROM, EEPROM, FLASH, NVRAM), a magnetic card, or an optical card. A computer program comprising software instructions is then stored on the readable medium.

[0132] The acquisition module 70 is for example configured to acquire at least one digital image of the internal surface 56 including the specific pattern 58 taken by each camera 50A, 50B.

[0133] In another example, the acquisition module 70 is configured to acquire a digital video stream recorded by each camera 50A, 50B, which corresponds to a plurality of successive digital images.

[0134] The acquisition module 70 is further configured to transmit the acquired data to the processing module 74.

[0135] Alternatively, the acquisition module 70 is also configured to store the acquired data.

[0136] As mentioned above, the input module 72 is configured to acquire input data entered by an operator via the human-machine interface 66.

[0137] The input data include, for example, information concerning the operator carrying out the intervention, the network 12 inspected, the number of pipes 16, 18 opening into the manhole 20 and their configuration or measurements read by the operator on the inspection device 10, such as the height of the inspection unit 30 read on the measuring system 28 or the angle of rotation of the rotary guide 40 relative to the support 38 of the positioning system 24.

[0138] Alternatively, if the inspection device 10 includes the system for determining geographic coordinates, in particular by satellite, certain input data information concerning the position of the inspection chamber 20 and / or the inspected network 12 is transmitted by the geographic coordinate determination system to the input module 72.

[0139] The input module 72 is further configured to transmit input data to the processing module 74.

[0140] The processing module 74 is configured to receive data acquired by the acquisition module 70 and input data acquired by the input module 72.

[0141] The processing module 74 is then configured to determine, from the received data and the characteristic distance d, at least one representative measurement of the manhole 20 and / or of a defined region present in the manhole 20, in particular of a pipe 16, 18 opening into the manhole 20.

[0142] In the example of [Fig.2], the representative measurements correspond to the coordinates X0, Z0, XI, Zl, X2, Z2, X3 and Z3 of the characteristic points PO, PO', PI, PI', P2, P2', P3, and P3' and / or to the diameters Dl, D2 and D3 of pipes 16, 18 opening into the manhole 20.

[0143] Each coordinate Xi corresponds to the distance between the central axis and the corresponding characteristic point Pi.

[0144] Each coordinate Zi corresponds to the depth of the corresponding characteristic point Pi. In other words, each coordinate Zi corresponds to the distance taken parallel to the central axis between the outer surface 21 and the corresponding characteristic point Pi.

[0145] The diameter Dl corresponds to the upstream diameter of the main pipe 16 measured at the level of the manhole 20. Similarly, the diameter D2 corresponds to the downstream diameter of the main pipe 16 and the diameter D3 to the diameter of the secondary pipe 18.

[0146] For this purpose, the processing module 74 is configured to determine the scale of the data recorded by each camera 50A, 50B from the characteristic distance d of the specific pattern 58 which is known beforehand.

[0147] Thus, the processing module 74 is suitable for converting a distance measured in number of pixels on an image or video stream recorded by a camera 50A, 50B into a distance in the metric system.

[0148] The processing module 74 is configured for example to identify the specific pattern 58 and / or the presence of a conduit 16, 18 on an image.

[0149] According to another example, the specific pattern 58 and / or a conduit 16, 18 are identified by an operator from the human-machine interface 66 and the processing module 74 is then configured solely to perform the conversion.

[0150] Preferably, the processing module 74 is configured to determine each representative measurement with an accuracy less than or equal to 5 cm.

[0151] Alternatively, the processing module 74 is further configured to determine, from the acquired data and the characteristic distance d, a data representative of a fouling rate of a pipe 16, 18 opening into the manhole 20. The fouling rate corresponds to the ratio between a fouling height at the level of the pipe 16, 18 and the diameter of the pipe 16, 18. The processing module 74 is therefore configured to determine a fouling height of a pipe 16, 18 from the acquired data and the characteristic distance d.

[0152] The human-machine interface 66 includes a screen 80 and a user interaction element 82.

[0153] The screen 80 is configured to display data recorded by at least one camera 50A, 50B including the specific pattern 58 and / or at least one representative measurement determined by the processing module.

[0154] The screen 80 provides the user with visual feedback on the operation and measurements performed by the device 10.

[0155] For example, the screen 80 is suitable for displaying a display window of the video stream recorded by each camera 50A, 50B, preferably instantaneously, and a display window of the representative measurements calculated by the processing module 74.

[0156] The interaction element 82 is connected to the processing unit 32, in particular to the input module 72.

[0157] The interaction element 82 is, for example, integrated into the screen 80 in the form of a touch screen. In this case, the screen 80 is, for example, suitable for displaying a third input data entry window.

[0158] According to another example, the interaction element 82 is a real or virtual keyboard or an actionable cursor connected to the screen 80 and the processing unit 32.

[0159] The interaction element 82 is configured for example to remotely activate and / or deactivate each camera 50A, 50B, the projection system 52 and / or each light source 54.

[0160] Alternatively, the interaction element 82 is also configured to control the longitudinal movement of the inspection unit 30 along the guide rod 26 and / or the rotation around the central axis.

[0161] In addition, the interaction element 82 allows the user to enter input data and transmit it to the input module 72. The interaction element 82 is configured for example to allow the user to choose the configuration of the pipes 16, 18 in the manhole 20 from a list of proposed configurations or to type a height read on the measuring system 28 or an angle of rotation.

[0162] A method for inspecting the underground network 12 of pipes 16, 18 will now be described. The inspection is carried out by an operator equipped with the inspection device 10 described above.

[0163] Initially, during a step of opening the buffer 22, the operator positions the buffer 22 in the open position of the manhole 20.

[0164] The operator lifts the buffer 20 and moves it in order to free access to the manhole 20.

[0165] Next, the operator installs the positioning system 24. The system of Positioning 24 is arranged outside and above viewpoint 20

[0166] For example, the positioning system 24 comprising a tripod, the operator deploys the tripod legs or the positioning elements 34 and optionally adjusts the leg height. The tripod is positioned at the periphery of the field of view 20.

[0167] The positioning system 24 is arranged so that the rotating guide 40 is aligned with the central axis of the sight 20.

[0168] The installation of the positioning system 24 is followed by a step of arranging the guide rod 26. In this step, the tubes 41 forming the rod 26 are assembled end to end and the rod 26 is engaged in the rotary guide 40.

[0169] For example, a first tube 41 is engaged in the rotating guide 40 and then a second tube 41 is fixed to the end of the first tube 41 by means of the fixing mechanism and so on until the rod 26 reaches the bottom of the manhole 20.

[0170] Alternatively, the tubes 41 are assembled end to end in the first instance and the mounted guide rod 24 is subsequently engaged in the rotary guide 40.

[0171] Furthermore, the inspection unit 30 is also engaged on the guide rod 26 by the operator above the outer surface 21, by engaging the half-shells 46, 48 on either side of the rod 26.

[0172] The measuring system 28 is fixed to the inspection unit 30 and extended along the guide rod 24 from the unwinder 42.

[0173] Next, the inspection unit 30 was lowered along the central axis following the guide rod 26.

[0174] The descent of the inspection unit 30 is, for example, carried out manually. Alternatively, it is controlled by the operator from the human-machine interface 66, more particularly from the interaction element 82.

[0175] In another example, the descent of the inspection unit 30 is generated by unwinding the tape of the measuring system 28 using the crank 44.

[0176] When the inspection unit 30 reaches a particular point located below the outer surface 21 in the manhole 20, the projection system 52 is activated, for example by activating a button on the human-machine interface 66.

[0177] The point is for example defined by the operator and corresponds for example to the moment when the inspection unit is opposite a pipe 16, 18 opening into the manhole 20.

[0178] Activation of the projection system preferably triggers a predefined sequence of measures, including projection of a specific pattern 58 and activation of at least one camera 50A, 50B.

[0179] The projection system 52 then projects the specific pattern 58 onto the internal surface 56 of the eye 20. At least one camera 50A, 50B is then activated.

[0180] Alternatively, the activation of the camera(s) 50A, 50B is for example manually controlled by the operator from the human-machine interface 66, more particularly from the interaction element 82.

[0181] For example, the projection of the specific pattern 58 and the activation of camera 50A, 50B are simultaneous.

[0182] Furthermore, each light source 54A, 54B is also activated.

[0183] After activation of the projection system 52 and at least one camera 50A, 50B, at least one image of the internal surface 56 of the eye 20 is taken by at least one camera 50A, 50B. Each image taken includes the specific pattern 58 projected by the projection system 52.

[0184] A first image 84 and a second image 86 in the near field taken by the camera 50A are shown in figures 5 and 6.

[0185] On [Fig.5], the first image 84 includes a secondary conduit 18 of diameter D3 arriving in drop into the manhole 20 and the specific pattern 58.

[0186] On [Fig.6], the second image 86 includes a main pipe 16 of upstream diameter DI at the bottom of the manhole 20 and the specific pattern 58.

[0187] Alternatively, a video stream is recorded by each camera 50A, 50B. The video stream is, for example, transmitted to the screen 80.

[0188] In an optional step, the operator enters the input data using the interaction element 82. The entered input data is acquired by the input module 72.

[0189] In another optional step, the geographic coordinate determination system transmits to the input module 72 data concerning the position of the processing unit 32, including information concerning the geographic position of the inspected manhole 20.

[0190] The image and / or video stream are then acquired by the acquisition module 70 and subsequently transmitted to the processing module 74.

[0191] The processing module 74 determines at least one representative measurement of the manhole 20 and / or of a defined region present in the manhole 20, in particular of a conduit 16, 18 opening into the manhole 20, from the characteristic distance d of the specific pattern 58.

[0192] Depending on the circumstances, the determination of at least one representative measurement also depends on the input data acquired by the input module 72, in particular the height of the inspection unit 30 read on the measuring system 28 or of the angle of rotation of the rotary guide 40 relative to the support 38.

[0193] For example, the processing module 74 receives the first image 84 of [Fig.5] and measures on the image 84 the number of pixels NP corresponding to the characteristic distance d, allowing a resolution R to be calculated in pixels per unit distance by calculating the ratio between the number of pixels NP and the characteristic distance.

[0194] Then, the processing module 74 converts lengths in a number of NPD pixels measured on the image 84 into lengths L in the metric system, for example by the following equation:

[0195] [Math.l] T NPP L = —

[0196] Since the resolution R is in pixels per unit distance, the length L is well determined in units of distance, preferably in the metric system.

[0197] In the example shown in the figures, the processing module 74 detects whether the image 84 contains a pipe, for example the secondary pipe 18, using a detection algorithm. If so, it determines a diameter of the pipe in pixels. Then, the processing module 74 divides the diameter determined in pixels by the resolution R to obtain the diameter (for example, the diameter D3) in the metric system.

[0198] When the inspection is complete, i.e., when all the desired representative measurements of the view 20 have been determined, each camera 50A, 50B is switched off. Similarly, the projection system 52 and each light source 54A, 54B are switched off.

[0199] The inspection unit 30 moves up along the central axis following the guide rod 26.

[0200] The raising of the inspection unit 30 is, for example, controlled manually by the operator, or alternatively, from the human-machine interface 66, more particularly from the interaction element 82.

[0201] In another example, the raising of the inspection unit 30 is generated by winding the measuring system 28 using the crank 44.

[0202] The inspection device 10 is then disassembled. In other words, the inspection unit 30 is disengaged from the guide rod 26, the guide rod 26 is removed from the sight 20 and the rotary guide 40 and the positioning system 24 is uninstalled.

[0203] Finally, the pad 22 is repositioned in the position of the eye 20.

[0204] In the example described above, the diameter calculation is automatically initiated by the operator when the system is facing the pipe. The The processing is done immediately and a measured diameter is presented to the operator on his tablet; he can validate or correct it before saving the data.

[0205] Alternatively, each image and / or video stream recorded by each camera 50A, 50B is stored and the determination of at least one representative measurement is carried out after the inspection unit 30 is raised and the manhole 20 is closed by the buffer 22.

[0206] Thanks to the inspection unit 30, the determination of representative measurements in the sight 20 is more precise and less risky for the operator.

[0207] In one variant, prior to the projection of the specific pattern 58, at least one camera 50A, 50B is activated when positioning the inspection unit 30 opposite the internal surface 56, to facilitate positioning.

[0208] In one variant, the inspection unit 30 is fixedly mounted on the guide rod 26. It is lowered through the sight 20 together with the guide rod 26.

Claims

Demands

1. A device (10) for inspecting a network (12) of underground pipes (16, 18) comprising a manhole (20), the manhole (20) extending around a central axis, the device being characterized by: - ​​a positioning system (24) intended to be disposed outside and above the manhole (20), - a longitudinal guide rod (26) intended to extend along the central axis, the rod (26) being intended to be inserted into the manhole (20) and mounted on the positioning system (24), and - an inspection unit (30) intended to be engaged on the guide rod (26), the inspection unit (30) being movable relative to the positioning system (24) at least along the central axis, the inspection unit (30) comprising: • at least one camera (50A, 50B), and • a projection system (52) configured to project a specific pattern (58) defining at least one characteristic distance (d) on an internal surface (56) of the gaze (20),the specific motif (58) being intended to be positioned in an area visible by at least one camera (50A, 50B), - a measuring system (28) configured to measure the height at which the inspection unit (30) is positioned along the central axis.

2. Device (10) according to claim 1, wherein the guide rod (26) is mounted rotatably relative to the positioning system (24) about the central axis, the inspection unit (30) being jointly movable in rotation about the central axis with the guide rod (26), the device (10) advantageously comprising an angular measurement system configured to determine the angle of rotation of the inspection unit (30) relative to the positioning system (24).

3. Device (10) according to any one of the preceding claims, wherein the inspection unit (30) further comprises at least one light source (54A, 54B) intended to illuminate the area visible by at least one camera (50A, 50B).

4. Device (10) according to any one of the preceding claims, the projection system (52) comprises at least one laser (62) configured to project the specific pattern (58) defining at least one characteristic distance (d) onto an internal surface (56) of the gaze (20).

5. Device (10) according to any one of the preceding claims, wherein the specific pattern (58) comprises at least two parallel segments (60) on the internal surface (56) of the eye (20).

6. Device (10) according to any one of the preceding claims, comprising a processing unit (32), the processing unit (32) comprising: - an acquisition module (70) configured to acquire data recorded by at least one camera (50A, 50B), and - a screen (80), the screen (80) being configured to display data recorded by at least one camera (50A, 50B) including the specific pattern (58).

7. Device (10) according to claim 6, wherein the processing unit (32) comprises a processing module (74) configured to determine, from the acquired data and the characteristic distance (d), at least one representative measurement of the manhole (20) and / or of a defined region present in the manhole (20), in particular of a pipe (16, 18) opening into the manhole (20), the screen (80) being advantageously configured to display the at least one representative measurement determined by the processing module (74).

8. Device (10) according to claim 7, wherein the processing module (74) is configured to determine from the acquired data and the characteristic distance (d), information representative of a fouling rate of a pipe opening into the manhole (20).

9. Device (10) according to any one of the preceding claims, wherein the inspection unit (30) comprises a first camera (50A) and a second camera (50B), the first camera (50A) being configured to capture near-field images and the second camera (50B) being configured to capture more distant field images inside the pipes (16, 18) opening into the manhole (20).

10. Device (10) according to any one of the preceding claims, wherein the inspection unit (30) comprises a lower region provided with a damping system.

11. Method for inspecting a network (12) of underground pipes (16, 18) comprising a manhole (20), the manhole (20) extending around a central axis, the method comprising the following steps: - supplying a device (10) according to any one of claims 1 to 14, - installing the positioning system (24); - arrangement of the guide rod (26) in the manhole along the central axis, and descent of the inspection unit (30) along the central axis jointly with the guide rod (26) or along the guide rod (26), - projection by the projection system (52) of the specific pattern (58) onto an internal surface (56) in the manhole (20), - taking at least one image of the internal surface (56) of the manhole (20) on which the specific pattern (58) appears using at least one camera (50A, 50B).

12. A method according to claim 11, comprising a step prior to the projection of the specific pattern (58), in which at least one camera (50A, 50B) is activated when the inspection unit (30) is positioned opposite the internal surface (56).

13. A method according to any one of claims 11 or 12, wherein the taking of at least one image is followed by a step of determining at least one representative measurement of the gaze (20) and / or of a defined region present in the gaze (20), in particular of a conduit (16, 18) opening into the gaze (20), from the characteristic distance (d) of the specific pattern (58).