US20220145608A1

US20220145608A1 - System and method for inspection of a sewer network

Info

Publication number: US20220145608A1
Application number: US17/518,908
Authority: US
Inventors: Louis Légaré Lapointe; Samuel Lambert; Krystof Charbonneau
Original assignee: Can Explore Inc
Current assignee: Can Explore Inc
Priority date: 2020-11-04
Filing date: 2021-11-04
Publication date: 2022-05-12
Also published as: CA3137560A1

Abstract

A system for inspection of a sewer network. The system comprises: a cleaning nozzle mounted on a hose; an inspection sled having a camera mounted thereon and a nozzle mounting section selectively engageable to the cleaning nozzle; and a position encoder configured to acquire position data representative of the position of the camera inside the conduit while the sled is moved inside the conduit by the movement of the cleaning nozzle and the camera captures images of the inner wall of the conduit. A method for inspection of a sewer network using the system is also provided.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35USC § 119(e) of U.S. provisional patent application(s) 63/109,626, the specification of which being hereby incorporated by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the field of sewer network inspection. More particularly, it relates to a system and a method for performing sewer network inspection, which leverages the components used for prior cleaning of the sewer line to move the inspection system used to perform the inspection and to determine the position of the inspection equipment inside the sewer network while inspection is being performed.

BACKGROUND

In the field of conduit inspections, it is common practice to perform a thorough cleaning of the conduits before performing conduit inspection. Such prior cleaning of the conduit is important to remove the accumulated particles, wastes and/or debris, in order to allow the passage of the inspection equipment inside the conduit and to perform a more detailed and accurate inspection. For example and without being limitative, the conduits being inspected can be sewer lines, water lines, or the like, ranging between about 150 mm and about 1500 mm in diameter.
Currently known methods and systems for performing the prior cleaning of the conduits and the subsequent inspection thereof, use different systems for each of these two distinct phases of the process. Hence, a cleaning system is commonly initially used to perform conduit cleaning and a distinct inspection system is commonly subsequently used to perform the inspection of the conduit, following the initial cleaning thereof. In more details, it is common to initially perform water pressure cleaning of the conduit, using a cleaning assembly including a conduit cleaning nozzle (or sewer cleaning nozzle) mounted to a water hose and moved longitudinally inside the conduit to project high pressure water onto the conduit wall and remove the accumulated particles, wastes and/or debris and to subsequently introduce an inspection robot in the conduit and move the inspection robot along the section of the conduit to be inspected, to acquire images of the conduit walls for this section.
Known systems and method using distinct components for performing the cleaning of the conduit and the subsequent inspection thereof, however, tend to suffer from several drawbacks. Indeed, the need for two distinct systems being used one after the other, results in economic loss from, for example and without being limitative, increased equipment acquisition costs, greater space required for transport of the equipment towards inspection sites, greater number of workers required for the operation of the multiple systems, increase time for setting up, operating and setting out the equipment, etc.
In view of the above, there is a need for an improved method and/or system for inspection of a sewer network which, by virtue of its design and/or components, would be able to overcome or at least minimize some of the above-discussed prior art concerns.

SUMMARY OF THE INVENTION

In accordance with a first general aspect, there is provided a system for inspection of a sewer network. The system comprises a cleaning nozzle mounted on a hose; an inspection sled having a camera mounted thereon and a nozzle mounting section selectively engageable to the cleaning nozzle; and a position encoder configured to acquire position data representative of the position of the camera inside the conduit while the sled is moved inside the conduit by the movement of the cleaning nozzle and the camera captures images of the inner wall of the conduit.
In an embodiment, the position encoder is configured to determine the position of the camera inside the conduit through measuring of the movement of the hose as the nozzle is moved inside the conduit, the hose being extended and retracted correspondingly in accordance with the movement of the nozzle inside the conduit.
In an embodiment the position encoder is mounted on a cleaning vehicle. The hose is connected to the cleaning vehicle and is selectively extended from the cleaning vehicle and winded back towards the cleaning vehicle in accordance with the forward and rearward movement of the nozzle inside the conduit. The movement of the hose is representative of the movement of the inspection sled inside the conduit, when the inspection sled is engaged to the cleaning nozzle.
In an embodiment, the position encoder is mounted on the inspection sled. The position encoder is configured to determine the position of the camera inside the conduit through measuring of a rotative movement of a rotative member of a displacement assembly rotating along with the movement of the sled inside the conduit induced by the movement of the cleaning nozzle.
In an embodiment, the nozzle mounting section includes an electromagnet activable to engage the cleaning nozzle to the nozzle mounting section of the sled.
In an embodiment, the nozzle mounting section includes a guiding funnel projecting at a front end of the nozzle mounting section, the guiding funnel being centered on the electromagnet.
In an embodiment, the sled includes a sled body and the nozzle mounting section includes an engagement body pivotally mounted to the sled body, using a hinge allowing pivoting of the engagement body with regard the sled body.
In an embodiment, the inspection sled further comprises lights configured to provide lighting of a at least a portion of a field of view of the camera.
In an embodiment, the camera and the position encoder are configured to generate time stamps. The corresponding time stamps associated to positions determined using the position encoder and to images captured by the camera are used to associate images to corresponding positions inside the conduit.
In accordance with another general aspect, there is also provided a method for inspection of a sewer network. The method comprises the steps of: moving a cleaning nozzle in a conduit to be inspected, the cleaning nozzle being mounted to a hose, at an end thereof; inserting a sled having inspection material mounted thereon in the conduit, the inspection material including a camera; engaging the cleaning nozzle with the sled; moving the guiding nozzle in the conduit and correspondingly moving the engaged sled in the conduit; and simultaneously to the sled being moved in the conduit by the movement of the guiding nozzle: capturing images of the inner wall of the conduit using the camera mounted on the sled; and acquiring position data through monitoring of the movement of the sled using a position encoder. The method also includes the step of determining a capture position for at least a subset of the images of the inner walls of the conduit captured by the camera, using the position data.
In an embodiment, the method further comprises the steps of inserting the cleaning nozzle in the conduit through a first manhole and inserting the inspection sled in the conduit via a second manhole.
In an embodiment, the step of acquiring position data through monitoring of the movement sled using a position encoder comprises monitoring the movement of the hose.
In an embodiment, the step of inserting the sled in the conduit comprises the sub steps of: engaging the sled to a guiding pole; lowering the sled in the conduit using the guiding pole; and disengaging the guiding pole from the sled.
In an embodiment, the sub step of engaging the sled to a guiding pole includes activating a pole engaging electromagnet and the sub step of disengaging the guiding pole from the sled includes deactivating the pole engaging electromagnet.
In an embodiment, the step of engaging the cleaning nozzle to the sled includes activating a nozzle electromagnet.
In an embodiment, the step of engaging the cleaning nozzle to the sled includes advancing the nozzle towards the sled and guiding the nozzle using a funnel.
In an embodiment, the method further comprises the step of removing the sled from the conduit, via the first manhole.
In an embodiment, the method further comprises simultaneously to the sled being moved in the first manhole: capturing images of the inner wall of the first manhole using the camera mounted on the sled; and acquiring position data through monitoring of the movement of the sled using the position encoder. The method also comprises determining a capture position for at least a subset of the images of the inner walls of the first manhole captured by the camera, using the position data.
In an embodiment, the method further comprises the initial step of circulating the cleaning nozzle in the conduit in order to perform cleaning of the conduit.
In an embodiment, the method further comprises generating time stamps for the captured images of the inner wall of the conduit using the camera and the positions of the position data generated through monitoring of the movement of the sled using the position encoder. The step of determining a capture position for at least a subset of the images of the inner walls of the conduit captured by the camera comprises uses the time stamps to associate images to corresponding capture positions inside the conduit.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, advantages and characteristics will become more apparent upon reading the following non-restrictive description of embodiments thereof, given for the purpose of exemplification only, with reference to the accompanying drawings in which:

FIG. 1 (Prior Art) is a top plan view of a prior art conduit cleaning nozzle for cleaning a conduit and shown in operation for cleaning of a conduit.

FIGS. 2a to 2f are schematic representations of the components of an inspection system, in accordance with an embodiment, wherein the components are positioned and moved along a sewer network during an inspection process in the course of FIGS. 2a to 2 f.

FIG. 3 is a top perspective view of an inspection sled of the inspection system shown in FIGS. 2a to 2f , in accordance with an embodiment and wherein the inspection sled is being shown mounted to a cleaning nozzle.

FIG. 3a is a rear elevation view of the inspection sled of FIG. 3 showing the camera and lights mounted on the camera mount of the inspection sled, in accordance with an embodiment.

FIG. 4 is a top perspective view of a position encoder of the inspection system shown in FIGS. 2a to 2f , in accordance with an embodiment.

FIG. 5 is a top perspective view of an inspection sled of an inspection system for inspection of a sewer network and mounted to a cleaning nozzle, in accordance with an embodiment where the displacement assembly of the sled is provided with skis.

FIG. 6 is a top perspective view of an inspection sled in accordance with an alternative embodiment where the connection member of the inspection sled is configured to be used in connection with a cleaning nozzle including an attachment loop.

FIG. 7 is a flowchart of the steps of the method for performing inspection of a sewer network in accordance with an embodiment.

DETAILED DESCRIPTION

In the following description, the same numerical references refer to similar elements. The embodiments, geometrical configurations, materials mentioned and/or dimensions shown in the figures or described in the present description are embodiments only, given solely for exemplification purposes.
Although the embodiments of the system for the inspection of a sewer network consist of certain components as explained and illustrated herein, not all of these components are essential and thus should not be taken in their restrictive sense. It is to be understood, as also apparent to a person skilled in the art, that other suitable components and cooperation therein between, as well as other suitable geometrical configurations, can be used for the sewer network inspection system, as will be briefly explained herein and as can be easily inferred herefrom by a person skilled in the art.
Moreover, although the associated method includes steps as explained and illustrated herein, not all of these steps are essential and thus should not be taken in their restrictive sense. It will be appreciated that the steps of the method for inspection of a sewer line described herein can be performed in the described order, or in any suitable order.
To provide a more concise description, some of the quantitative and qualitative expressions given herein can be qualified with the terms such as “about” and “substantially”. It is understood that whether the terms “about” and “substantially” are used explicitly or not, every quantity or qualification given herein is meant to refer to an actual given value or qualification, and it is also meant to refer to the approximation to such given value or qualification that would reasonably be inferred based on the ordinary skill in the art, including approximations due to the experimental and/or measurement conditions for such given value.
In accordance with the embodiments described in more details below, there is provided a system and a method for performing inspection of a sewer network. As will become clear by reading the description below, the system is designed to take advantage of the components provided to perform the cleaning of the conduit, in order to perform the inspection of at least a section of the conduit. The inspection is performed by moving a camera longitudinally along a previously cleaned section of the conduit to simultaneously: A) capture images of the inner walls of the section of the conduit; and B) continuously determine the position of the camera within the conduit section as images are being captured.
In the course of the description below, one skilled in the art will understand that while the system is described herein in reference to cleaning and inspecting of a “conduit”, the system could also be used to perform similar cleaning and/or inspection of a manhole in which the components of the system are moved, with the system operating similarly in “manholes” as in “conduits”. Hence, even though the system is described in view of its operation for cleaning and inspecting “conduits”, the description below also extends to cleaning and/or inspection of “manholes” of a sewer network. In an embodiment, the system and method are designed to move a camera within a section of conduit having previously been cleaned using the cleaning nozzle connectable to a sled, which will be described in more details below.
In view of the above, one skilled in the art will understand that the system is designed to capture a combination of images (i.e. an image or a sequence of images, which can be continuous to define a video sequence or discontinuous to present a series of distinct images) from inside the cleaned conduit. The simultaneous capture of the images and determination of the position of the camera capturing the images within the conduit, allows each image being captured to be associated to a specific position in the conduit. In an embodiment conduit inspection metadata can also be generated during the inspection. The conduit inspection metadata can, for example and without being limitative be inputted manually by a user, be inputted by voice command by a user, be automatically generated during the capture of the images by the system, be generated through a combination of manual input and automatic generation, etc.
In an embodiment, the captured images and the position data can subsequently be stored in an inspection data database. The conduit inspection metadata associated to the captured images can be concatenated (or joined) to the images in the inspection data database. One skilled in the art will understand that, in alternative embodiments, the conduit inspection metadata can also be stored in a distinct database linked to the inspection data database, such that the conduit inspection metadata are associated to the corresponding images using interrelated databases.
In the course of the present description, for ease of description and concision, the term “images” is used to refer to either a single image or a sequence of images (which includes a video presenting a plurality of successive images) showing the inside of a conduit. One skilled in the art will also understand that the term “image” can also be used in the present description to refer to a tridimensional representation of the inside of a conduit, such as, for example and without being limitative a point cloud. The term “image” can also be used to define a combination of a single image or a sequence of images (e.g. a video) and the tridimensional representation of the inside of the conduit. It will be understood that a point cloud can be generated using different methods and technologies such as, for example and without being limitative, by stereoscopy where processing of overlapping images is performed to obtain the tridimensional representation of the inside of the conduit, using a 3D scanner scanning the inner surface of the conduit wall, etc. Hence, in the description below, it will be understood that any reference to a “camera” should be understood to refer more generally to imaging equipment and to include the possibility of a single (or a plurality of) 360° cameras and/or a 3D scanner scanning the inner surface of the wall of the conduit, to generate a point cloud.
One skilled in the art will understand that the captured images and the associated position data and conduit inspection metadata can subsequently be used to identify the presence (or absence) and the position of conduit specific characteristics which can be identified in the images and which are relevant for the description, and the evaluation of the condition and/or the performance of the conduit.
FIG. 1 (Prior Art) shows a conventional cleaning nozzle 20, such as those currently used to alter the direction of flow and velocity of the water and perform hydro-jet cleaning of conduits. The cleaning nozzle 20 includes fluid outlets 22 from which high-pressured jets 24 of water are projected as the nozzle 20 is moved within a conduit, to remove buildups and debris inside the conduit. One skilled in the art will understand that the shape and/or size of the cleaning nozzle 20, as well as the position, angles and size of the fluid outlets 22 can vary, for example and without being limitative, to be adapted to specific cleaning applications and/or to the conduit to be cleaned. In many cases, different nozzles 20 can be used successively to perform cleaning of a conduit.
In order to be provided with a water flow, the nozzle 20 is connected to a hose 52. In an embodiment, the hose 52 is connected to a pressure-washing apparatus (not shown) including a pump (not shown) generating water pressure and feeding a high-pressure water flow into the hose 52 and to the nozzle 20. The pressure washing apparatus can be connected to a water source using a second distinct hose (not shown). For example and without being limitative, in an embodiment, the pressure washing apparatus (not shown) can be installed in a cleaning vehicle movable to the location of the conduit to be cleaned.
In FIG. 1, a rigid pipe section 25 is shown connected to the nozzle 20. In such an embodiment. The hose 52 is connected to a distal end 25 b of the pipe section 25, with the proximal end 25 a of the pipe section 25 being connected to the nozzle 20.
One skilled in the art will understand that the cleaning nozzle 20 can be used in combination with a vacuum (not shown) operating to suction and remove the dislodged buildups and debris from the conduit. In an embodiment, the vacuum can be connected to a collection tank receiving and storing the collected buildups and debris.

General Description of the System

Now referring to FIGS. 2a to 3a there is shown an embodiment of the inspection system 110, wherein the features are numbered with reference numerals in the 100 series, which correspond to the reference numerals of the prior art elements described above.
The inspection system 110 includes an inspection sled 130 having inspection equipment mounted thereto and being insertable and movable inside a conduit 170, for inspection of an inner portion 172 thereof. The inspection sled 130 and the inspection equipment mounted thereto will be described in more details below. The inspection sled 130 is connectable to a cleaning nozzle 120 movable inside a conduit 170 for performing cleaning thereof. In an embodiment, after the cleaning of the conduit 170 has been performed using the cleaning nozzle 120, the retraction movement of the nozzle 120 can be used to drive the sled 130 inside the conduit 170 to perform inspection thereof. Indeed, in an embodiment, the inspection sled 130 is configured to be engaged by the cleaning nozzle 120, once the cleaning nozzle 120 has been moved forward inside the conduit 170 for the last time in the process of cleaning the conduit 170, as will be described in more details below. Therefore, in the embodiment shown, after being connected to the cleaning nozzle 120, the inspection sled 130 can be moved inside the conduit 170 to perform inspection thereof, as the cleaning nozzle 120 is retracted to be removed from the conduit 170. Once again, the connection mechanism for connecting the cleaning nozzle 120 to the inspection sled 130 will be described in more details below.
One skilled in the art will however understand that, in alternative embodiments (not shown), the inspection sled 130 could also be connected to the cleaning nozzle 120 as the cleaning nozzle 120 is moved inside the conduit 170 to perform the cleaning thereof. In an embodiment, the inspection sled 130 could be moved inside the conduit 170 to perform inspection thereof, as the cleaning nozzle 120 is moved inside the conduit 170 (either forwards or rearward) in the process of cleaning the conduit 170.
In the embodiment shown, the inspection system 110 also includes a position encoder 160 working in combination with the hose 152 onto which the cleaning nozzle 120 is mounted. Hence, when the hose 152 is moved along with the movement of the nozzle 120 in the conduit (and drive the sled 130 inside the conduit 170), the movement of the hose 152 can be tracked by the position encoder 160, to determine the movement (and incidentally the position) of the nozzle 120 and the sled 130 connected thereto inside the conduit 170. Once again, the position encoder 160 will be described in more details below. It will also be understood that, in an alternative embodiment, the position encoder 160 could be configured to track the movement of the nozzle 120 (and incidentally the movement of the inspection equipment mounted onto the sled 130) by tracking the rotation of a rotative shaft rotating along with the movement of the sled 130, such as, for example, a rotative shaft of a wheel of the sled 130, or the like.

Positioning and Movement of the Components Inside the Conduit

Referring more particularly to FIGS. 2a to 2f , an embodiment where the inspection sled 130 is configured to be engaged by the cleaning nozzle 120 once the cleaning nozzle 120 has been moved forward inside the conduit 170 for the last time in the process of cleaning the conduit 170 is shown. In the embodiment shown, a pressure-washing apparatus (not shown) is installed in a cleaning vehicle 150 movable in proximity to a first manhole 151 a (or any other access conduit) allowing access to the conduit 170 to be inspected.
Hence, as shown more clearly in FIG. 2a , the cleaning nozzle 120 and the associated hose 152 onto which the nozzle 120 is mounted can be inserted into the conduit 170 and the cleaning nozzle 120 can be moved back and forth inside the conduit 170 to perform cleaning thereof. Once the cleaning nozzle 120 has been circulated back and forth inside the conduit 170 a sufficient number of times to perform the desired cleaning, the nozzle 120 can be moved forward inside the conduit 170 one last time, until it reaches a position located proximate to the outlet of a second manhole 151 b distant from the first manhole 151 b.
As shown more clearly in FIG. 2b , in the embodiment shown, the sled 130 can be lowered into the conduit 170 via the second manhole 151 b, simultaneously with the cleaning of the conduit or subsequently thereto. Hence, the sled 130 is introduced in the conduit 170 in a location remote from the first manhole 151 a in which the hose 152 and the cleaning nozzle 120 were originally introduced and from which the hose 152 protrudes. In the embodiment shown, the inspection sled 130 can be lowered in the second manhole 151 b using a pole selectively connectable to the sled 130 using a pole electromagnet 154. In the embodiment shown, the electromagnet 154 is positioned at an extremity of the pole 153 and is connectable to a magnetic section 133 of the sled 130 configured to connect with a magnet. One skilled in the art will understand that, in an alternative embodiment (not shown), the electromagnet could rather be placed on the sled 130, to connect with a magnetic end of the pole 153. It will also be understood that, in other alternative embodiments (not shown), different temporary connecting means could be used to selectively connect the sled 130 with the pole 153. Furthermore, in other alternative embodiments a different component than a pole, such as, for example and without being limitative, a rope or the like, could be used to lower the sled 130 in the conduit, through the second manhole 151 b.
In the embodiment shown, the electromagnet 154 can be activated to engage the pole 153 with the magnetic section 133 of the sled 130 and maintain the two objects connected, while the pole 153 is used to lower the sled 130 through the second manhole 151 b and in the conduit 170.
As shown more clearly in FIGS. 2c and 2d , in an embodiment, once the sled 130 is in place, the nozzle 120 can be moved forward inside the conduit 170 towards the sled 130, until it reaches the sled 130 and connects therewith. The sled 130 includes a nozzle connecting section 140 configured to selectively connect the nozzle 120 to the sled and maintain the nozzle 120 and the sled 130 attached to one another for a desired period of time. In the embodiment shown, the nozzle mounting section 140 includes a nozzle electromagnet 141 activable to attract the nozzle 120 and temporarily connect the nozzle 120 with the nozzle electromagnet 141. The sled 130 and its nozzle connecting section 140 will be described in more details below. For example and without being limitative, in an embodiment, the nozzle electromagnet 141 (or other corresponding electromagnet) can be activated/deactivated using a remote-control system (not shown).
It should be noted that one skilled in the art will understand that, in alternative embodiments (not shown), the electromagnet can be placed on the nozzle 120 rather than the sled 130 or that other assemblies or method, differing from the described electromagnet could be used to selectively and temporarily connect the sled 130 with the nozzle 120.
In the embodiment shown, once the sled 130 is in place and the nozzle 120 is mounted to the nozzle connecting section 140 of the sled 130, the pole electromagnet 154 can be deactivated to disconnect the pole 153 from the sled 130 and the pole 153 can be withdrawn, with the sled 130 being left in the conduit 170, close to the outlet of the second manhole 151 b. Once again, for example and without being limitative, in an embodiment, the electromagnet 154 can be deactivated using a remote-control system (not shown).
As shown more clearly in FIG. 2e , once the nozzle 120 is joined to the nozzle connecting section 140 of the sled 130, the sled 130 can be driven by the movement of the nozzle 120 being retracted (e.g. being moved back towards the cleaning vehicle 150 in the embodiment shown), to move the sled 120 along the conduit 170 (i.e. along the section of the conduit 170 defined between the second manhole 151 b and the first manhole 151 a). In other words, in the embodiment shown, the hose 152 onto which the nozzle 120 is mounted can be winded back, to retrieve the nozzle 120 and move the sled 130 attached thereto along the conduits 170, towards the cleaning vehicle 150.
During the movement of the sled 130 inside the conduit 170, the camera 136 mounted on the sled 130 can be activated to capture images of the inner portion 172 (or inner walls) of the section of the conduit 170. Once again, for example and without being limitative, in an embodiment, the camera 136 can be activated/deactivated using a remote-control system (not shown).
Simultaneously to the capture of the images by the camera 136, the system 110 is configured to record the position of the sled 130 (and the camera 136 mounted thereon) inside the conduit 170, such that the images captured can be associated to a corresponding location inside the conduit 170. In an embodiment, the position is determined using a rotary position encoder 160 mounted on the cleaning vehicle 150 and brought in rotation by the movement of the hose 152. Therefore, when the hose 152 is moved, the movement of the hose 152 produces rotation of a main shaft 162 of the position encoder 160, which can subsequently be used to determine the movement of the sled 130 and its corresponding position over time. For example and without being limitative, in an embodiment, the camera 136 and the position encoder 160 are configured to generate time stamps. The corresponding time stamps associated to positions determined using the position encoder 160 and to images captured by the camera 136 are used to associate images to corresponding positions (or coordinates). One skilled in the art will understand that, in an embodiment the data generated by additional components of the inspection equipment mounted onto the sled 130 could generate time stamp also being used to associate images to corresponding positions (or coordinates).
Now referring to FIG. 2f , once the sled 130 has reached the first manhole 151 a, the sled 130 can be brought back up in the first manhole 151 a to be retrieved. In an embodiment, the inspection is ended once the sled 130 has reached the first manhole 151 a and before the sled 130 is brought back up inside the first manhole 151 a by further winding up of the hose 152 and the corresponding movement of the nozzle 120. In an alternative embodiment, inspection of the first manhole 151 a can also be performed as the sled 130 is brought back up inside the first manhole 151 a, by further winding up of the hose 152.
As previously mentioned, one skilled in the art will understand that, in alternative embodiments (not shown), the inspection sled 130 could be mounted to the cleaning nozzle 120 at a different point in time than what is described in the embodiment above and could be introduced into the sewer network from a different point of entrance than the second manhole 151 b. Similarly, inspection could be performed concurrently with the cleaning of the conduit 170 by the cleaning nozzle 120.

Components of the System

Now referring to FIGS. 3 to 4, the components of the system 110 will be described in more details below.
FIG. 3 shows in more details, the inspection sled 130 which is insertable in the conduit 170 and connectable to the nozzle 120. The inspection sled 130 has a sled frame 132 defining a sled body 131 onto which the inspection elements are mounted.
The sled 130 also includes a displacement assembly 137 mounted to the sled frame 132 and supporting the frame 132 on the ground, to allow easy movement of the sled 130 along the conduit 170. In the embodiment shown, the displacement assembly 137 includes a plurality of wheels 137 a, but one skilled in the art will understand that, in alternative embodiments, other elements favoring the displacement of the sled 130, such as skis, tracks, or the like, could be used as part of the displacement assembly.
The sled 130 also includes a camera mount 138 mounted to the frame 132. In the embodiment shown, the camera mount 138 is positioned, at a rear end 131 a of the sled body 131, but one skilled in the art will understand that, in alternative embodiments (not shown), it could be positioned at a different position. The camera mount 138, has a mounting frame 138 a sized and shaped to receive a camera 136 and lights 139. In FIG. 3, the camera mount 138 is shown free of camera and lights. FIG. 3a shows an embodiment of the camera mount 138 having a camera 136 and lights 139 mounted thereon. The mounting frame 138 a is made of a material strong enough to support the camera 136 and the lights 139 and capable of resisting the heat generated by the lights 139 without being damaged. For example and without being limitative, in an embodiment the mounting frame can be made of aluminum, steel, polymer material offering a sufficient rigidity and heat resistance, etc.
The camera 136 and lights 139 are configured to capture images of the surroundings of the inspection sled 130 and can be any type of camera and/or light available on the market with characteristics adapted to allow the capture of the images in a corresponding conduit. For example and without being limitative, in an embodiment, the camera 136 can be a 360° camera, such as, for example and without being limitative a GoPro™ Max camera, a combination of two 180° cameras facing opposite directions, or the like. In an embodiment, the camera 136 could rather be embodied by a 3D scanner, such as for example and without being limitative a LiDAR scanner, a laser profiler, or other equipment allowing 3D scanning. In an embodiment the camera 136 could also be embodied by a combination of the above mentioned 360° degree camera, combination of 180° degree cameras and a 3D scanner.
The lights 139 are lights lighting at least a portion of the field of view of the camera 136 and providing a lighting capacity appropriate for the capture of clear images by the camera 136 in the dark environment of the conduit 170. Hence, the lights 139 are selected and oriented to provide a sufficient lighting power, adapted beam lights and a good white balance for the capture of the images inside the conduit 170. For example and without being limitative, in an embodiment (not shown), a combination of a LED lighting apparatus 139 a providing flood lighting in the proximity of the camera 136 and focalized lights 139 b providing focalized lighting further away from the camera 136, in the field of view thereof, can be used. One skilled in the art will understand that, in alternative embodiments (not shown), other lighting combination can be used. It will also be understood that, in an embodiment (not shown), the lights 139 can be mounted to the frame 132 of the sled 130 or onto a combination of the frame 132 of the sled 130 and the camera mount 138.
In the embodiment shown, the sled 130 further includes a nozzle mounting section 140. The nozzle mounting section 140 is positioned, at a front end 131 b of the sled body 131 (i.e. at an end of the body engageable with the nozzle 120 and being the leading end of the sled 130 when the sled 130 is moved inside the conduit by the movement of the nozzle 120), and is configured to be engageable by the nozzle 120. In the embodiment shown in FIG. 3, the nozzle mounting section 140 includes an engagement body 142 projecting forward from the sled body 131 and positioned, sized and shaped to selectively engage with the nozzle 120. In the embodiment shown, the nozzle mounting section 140 includes a nozzle electromagnet 141 at a forward end thereof. The nozzle electromagnet 141 is activable to attract the nozzle 120 and temporarily connect the nozzle 120 with the engagement body 142 of the sled 130 and deactivable to break the connection therebetween.
In the embodiment shown in FIG. 3, the engagement body 142 is pivotally mounted to the sled body 131, using a hinge 143 allowing upward pivoting of the engagement body 142. The pivotal connection between the engagement body 142 and the sled body 131 can help the transition of the sled from the conduit 140 to the first manhole 151 a, when the sled 130 is being retrieved from the conduit 170 (as described in more detailed above in connection with FIG. 2f ). It will be understood that, in an alternative embodiment (not shown) the engagement body 142 could be rigidly mounted to the sled body 131. In another alternative embodiment (not shown), the engagement body 142 could be pivotally mounted to the sled body 131, using a rotative connection allowing movement along a 360° range, amongst other things, to help minimize the effect of the twist in the hose 152 on the sled 130.
In the embodiment shown, the engagement body 142 further includes a guiding funnel 144 projecting forward from the engagement body 142, at the front end thereof. The guiding funnel 144 is centered on the nozzle electromagnet 141 and reduces in size as it gets closer to it. Hence, when the nozzle 120 approaches the sled 130 positioned in the conduit 140, the funnel 144 guides the nozzle 120 towards the electromagnet 141 to ease the connection of the two components.
Referring again to FIG. 3, In an embodiment, the sled 130 includes a magnetic section 133 configured to connect with the electromagnet of the guiding pole (as described in more details above). As already mentioned, in an alternative embodiment, the electromagnet for magnetic connection with the pole 153 can be provided on the sled 130.
In an embodiment, the sled 130 also includes a battery 146. The battery 146 can be connected to the components requiring power, such as, for example and without being limitative, the camera 136, the lights 139, the nozzle electromagnet 141 or the like.
In an embodiment, the sled 130 can also include an inertial measurement unit (IMU) including components such as, for example and without being limitative, accelerometers, gyroscopes, magnetometers, to monitor the and report the force, angular rate and/or orientation of the sled 130 as it is moved inside the conduit.
In an embodiment, the sled 130 can also include a battery 146. The battery 146 can be connected to the components requiring power, such as, for example and without being limitative, the camera 136, the lights 139, the nozzle electromagnet 141 or the like.
In an embodiment, the sled 130 can further include an audio recording assembly allowing recording of the sounds of the surrounding of the sled 130, for example to allow an operator to record data relative to which conduit is being inspected or is going to be inspected by the sled 130.
In an embodiment, a computer 147 (or computing unit) could also be provided on the sled 130, for example to allow remote control of the components mounted on the sled 130, such as the camera 136, the lights 139, the nozzle electromagnet 135 or the like. In an embodiment, the computer 147 can include storage medium for storing data. In an alternative embodiment, additional storage medium distinct from the storage medium of the computer 147 can also be provided. Hence the data acquired by the components of the inspection sled 130, such as the camera 136 or the like, can be stored in the storage medium for subsequent transfer to an external processing unit (not shown) processing the data acquired using the components of the inspection sled 130 (i.e. transfer to the external processing following extraction of the inspection sled 130 from the conduit, for example using short range communication, wired connection, or the like). In an alternative embodiment, the data acquired by the components of the inspection sled 130 can be transmitted to an external processing unit in real time (or near real time) through a wired connection running along the hose 152 of the system, or through wireless connection, for example using connection relays positioned inside the conduit.
In an alternative embodiment, other mechanism or methods could be used to remotely or mechanically activate/deactivate the components.
Now referring to FIG. 4, the position encoder 160 of the inspection system 110 is shown, in accordance with an embodiment. In an embodiment, the position encoder 160 is mounted proximal to the source of the hose 152 to which the cleaning nozzle 120 is connected. In the embodiment shown, the position encoder 160 is mounted to the cleaning vehicle 150.
One skilled in the art will however understand that, in an alternative embodiment, the position encoder 160 could be positioned to engage the hose 152 at any position along the hose 152 which allows monitoring of the movement of the hose 152. Hence, it can be mounted to any structure or element allowing the position encoder 160 to be held in place as the hose is winded/unwinded and engages the position encoder 160.
One skilled in the art will also understand that, in alternative embodiments (not shown), the position encoder 160 could monitor the movement of an element different than the hose 152 in order to monitor the movement of the sled 130, to determine its corresponding position over time. For example and without being limitative, the position encoder 160 can be mounted directly on the sled 130, and be configured to monitor the movement of the corresponding nozzle 120 and the sled 130 connected thereto (along with the camera 136 mounted onto the sled 130) within the conduit 170, through measuring of a rotative movement of a rotative member of the displacement assembly 137 rotating along with the movement of the sled 130 inside the conduit 170. For instance, the position encoder can monitor the rotation of a wheel (or a shaft thereof) indicative of the movement of the sled 130, or the like.
In the embodiment shown, the position encoder 160 includes a main shaft 162 rotatable by the movement of the hose 152 circulating in the position encoder 160 and the necessary components such as, detectors, electronics, circuitry and the like for providing feedback regarding the position and/or movement of the main shaft 162. Rotary encoders are known in the art and one skilled in the art will understand that numerous types of rotary encoders could be used as part of the present inspection system 110, to monitor the position of the camera 136 within the conduit 140. For example and without being limitative, one skilled in the art will understand that the position encoder 160 can be an absolute rotary encoder or an incremental rotary encoder.
In the inspection system 110, the angular movement (or the angular position) of the main shaft 162 is used to determine the movement of the hose 152 and consequently the movement of the corresponding nozzle 120 and the sled 130 connected thereto within the conduit 140. Given that the camera 136 is mounted on the sled 130, the movement of the camera 136 can be continuously determined using the data of the position encoder 160, as will be described in more details below.
In the embodiment shown, the position encoder 160 includes a main body 164 attachable to a section of the cleaning vehicle 150. The main shaft 162 is rotatably mounted relative to the main body 164. The position encoder 160 also includes a biasing pulley 166 biased towards the main shaft 162 by a biasing assembly 167, in order to bias the hose 152 towards the main shaft 162. In other words, a free space is defined between the main shaft 162 and the biasing pulley 166 for the hose 152 to move therebetween. To ensure a sufficient contact between the hose 152 and the main shaft 162 to drive the main shaft 162 in rotation when the hose 152 is moved thereabout, the biasing pulley 166 is pressed towards the main shaft 162 by springs 168 of the biasing assembly 167 and presses the hose 152 onto the main shaft 162.
As described above, when the hose 152 is moved and drives the sled 130 inside the conduit 170 (e.g. when the hose is pulled to remove (or withdraw) the nozzle 120 from the conduit 170), the movement of the hose 152 can therefore be tracked by the position encoder 160, to determine the movement (and incidentally the position) of the nozzle 120 and the sled 130 connected thereto inside the conduit 170.
In view of the above, the combination of the position encoder 160 monitoring the movement of the hose 152 and the camera 136 being mounted on the sled 130 moved concurrently with the movement of the hose 152, allows the simultaneous capture of the images and determination of the position of the camera 136 within the conduit. Hence, each captured image can be associated to a position in the conduit 170. In an embodiment, the position encoder 160 and the camera 136 can be used to collect data to be subsequently imported to a computer (not shown) which processes the position data from the position encoder 160 and the images from the camera 136 to generate the images with the associated position. One skilled in the art will understand that, as previously described, any mean or method which allow data communication between the camera 136, position encoder 160 and the external computer (or processing unit) can be used, such as, wired or wireless connection over a network, importation of data using external data storage such as memory cards, or the like. As previously mentioned, conduit inspection metadata can also be generated, and the images and the position data can subsequently be stored in an inspection data database.
It will be understood that different types of inspection sleds capable of receiving the necessary equipment (camera 136, lights 139, battery 146, computer 147, IMU, audio recording assembly, engagement body 142, nozzle electromagnet 141, etc.) could be used, for example to adapt to different conduit sizes, configurations conditions, etc. One skilled in the art will understand that the design and configuration of the sled 130 should favor insertion/retrieval of the sled 130 in the corresponding manholes 151 a, 151 b, easy connection of the nozzle 120 with the nozzle mounting section 140, quality of the images captured during inspection and maneuverability and stability of the sled 130 in the conduit 140 during displacement.
For example and without being limitative, FIG. 5 shows a sled 230 in accordance with an alternative embodiment of the inspection system, wherein the features are numbered with reference numerals in the 200 series, which correspond to the reference numerals of the previous embodiment described above. In the embodiment of FIG. 5, the sled 230 is provided with a displacement assembly 237 with skis 137 b instead of the wheels shown in FIG. 3 and being more compact. It will be understood that only partial equipment, and only the camera mount, without the camera and lights, is shown on the sled 230 of FIG. 5, but the sled 230 could include all the equipment of the sled shown in the previous embodiment.
FIG. 6 shows a sled 330 in accordance with an alternative embodiment of the inspection system, wherein the features are numbered with reference numerals in the 300 series, which correspond to the reference numerals of the previous embodiment described above. In FIG. 6, a sled having an alternative connection assembly for selectively connecting the nozzle 320 to the sled 330 is shown. In the embodiment of FIG. 6, the nozzle 320 is provided with an attachment loop 326 at the attachment end thereof. The nozzle mounting section 340 of the sled 330 includes an attachment bracket 345 (rather than the previously described nozzle electromagnet) onto which the attachment loop 326 of the nozzle 320 is securable, by insertion of a locking pin 345 a of the attachment bracket 345 into the attachment loop 326 of the nozzle 320. For example and without being limitative, the insertion of the locking pin 345 a into the attachment loop 326 of the nozzle 320 can be performed by an operator to secure the nozzle 320 to the sled 330.
The inspection system having been described in detail above, the method for inspection of a conduit will now be described in more details below in reference to FIG. 7.
As previously mentioned, in an embodiment the method 400 includes the initial step 410 of inserting a cleaning nozzle in a conduit to be inspected and cleaning the conduit by movement of the cleaning nozzle therein. In other words, this steps is performed by inserting the and moving the cleaning nozzle in the conduit to be inspected in order to perform cleaning of the conduit, the cleaning nozzle being mounted on a hose. In an embodiment, the nozzle is inserted in the conduit through a first manhole.
The method also includes the step 420 of inserting an inspection sled having inspection material mounted thereon in the conduit, using a second manhole. In an embodiment, this step includes the sub steps of engaging the sled to a guiding pole (or other elements allowing controlled lowering of the sled), lowering the sled in the conduit using the guiding pole and disengaging the guiding pole from the sled. In an embodiment, the substep of engaging the sled to a guiding pole includes activating a pole engaging electromagnet and the substep of disengaging the guiding pole from the sled includes deactivating the pole engaging electromagnet.
The method also includes the step 430 of engaging the cleaning nozzle with the sled and the further step 440 of moving the moving the guiding nozzle (through movement of the hose onto which the cleaning nozzle is mounted) inside the conduit to correspondingly move the engaged sled in the conduit. Simultaneously to the sled being moved in the conduit, the method includes the step 450 of capturing images of the inner wall of the conduit using a camera mounted on the sled.
In an embodiment, the step 440 of moving the hose inside the conduit includes winding back the hose to retrieve the guiding nozzle and move the engaged sled in the conduit.
In an embodiment, the step 430 of engaging the cleaning nozzle to the sled includes activating a nozzle electromagnet to bias the nozzle towards the nozzle mounting section of the inspection sled and maintain the nozzle in engagement therewith. In an embodiment, this step 430 also includes advancing the nozzle towards the sled and guiding the nozzle using a funnel.
Simultaneously to the capture of images by the camera, the method also includes the step 460 of acquiring position data through monitoring of the movement of the hose being winded back using a position encoder. The method further includes the step 470 of determining a capture position for at least a subset of the images of the inner walls of the conduit captured by the camera, using the position data.
In an embodiment, this step includes generating time stamps for the captured images of the inner wall of the conduit using the camera and the positions of the position data generated through monitoring of the movement of the sled using the position encoder, and using the time stamps to associate images to corresponding capture positions inside the conduit. Once again, one skilled in the art will understand that, in an embodiment, this step could include generating time stamps for the data generated by additional components of the inspection equipment mounted onto the sled and using the time stamps to associate images to corresponding positions (or coordinates).
In an embodiment, the method further includes removing the sled from the conduit, via the first manhole. In an embodiment, this step is performed simply by winding back the hose until the sled is removed from the conduit via the first manhole. In an embodiment, this step can include the sub steps of: capturing images of the inner wall of the first manhole using the camera mounted on the sled, acquiring position data through monitoring of the movement of the sled using the position encoder; and determining a capture position for at least a subset of the images of the inner walls of the first manhole captured by the camera, using the position data, being performed simultaneously to the sled being moved in the first manhole.
Several alternative embodiments and examples have been described and illustrated herein. The embodiments of the invention described above are intended to be exemplary only. A person of ordinary skill in the art would appreciate the characteristics of the individual embodiments, and the possible combinations and variations of the components. A person of ordinary skill in the art would further appreciate that any of the embodiments could be provided in any combination with the other embodiments disclosed herein. It is understood that the invention could be embodied in other specific forms without departing from the central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein. Accordingly, while the specific embodiments have been illustrated and described, numerous modifications come to mind. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.

Claims

1. A system for inspection of a sewer network, the system comprising:

a cleaning nozzle mounted on a hose;

an inspection sled having a camera mounted thereon and a nozzle mounting section selectively engageable to the cleaning nozzle; and

a position encoder configured to acquire position data representative of the position of the camera inside the conduit while the sled is moved inside the conduit by the movement of the cleaning nozzle and the camera captures images of the inner wall of the conduit.

2. The system of claim 1, wherein the position encoder is configured to determine the position of the camera inside the conduit through measuring of the movement of the hose as the nozzle is moved inside the conduit, the hose being extended and retracted correspondingly in accordance with the movement of the nozzle inside the conduit.

3. The system of claim 2, wherein the position encoder is mounted on a cleaning vehicle, the hose being connected to the cleaning vehicle and being selectively extended from the cleaning vehicle and winded back towards the cleaning vehicle in accordance with the forward and rearward movement of the nozzle inside the conduit, the movement of the hose being representative of the movement of the inspection sled inside the conduit, when the inspection sled is engaged to the cleaning nozzle.

4. The system of claim 1, wherein the position encoder is mounted on the inspection sled, the position encoder being configured to determine the position of the camera inside the conduit through measuring of a rotative movement of a rotative member of a displacement assembly rotating along with the movement of the sled inside the conduit induced by the movement of the cleaning nozzle.

5. The system of claim 1, wherein the nozzle mounting section includes an electromagnet activable to engage the cleaning nozzle to the nozzle mounting section of the sled.

6. The system of claim 5, wherein the nozzle mounting section includes a guiding funnel projecting at a front end of the nozzle mounting section, the guiding funnel being centered on the electromagnet.

7. The system of claim 1, wherein the sled includes a sled body and the nozzle mounting section includes an engagement body pivotally mounted to the sled body, using a hinge allowing pivoting of the engagement body with regard the sled body.

8. The system of claim 1, wherein the inspection sled further comprises lights configured to provide lighting of a at least a portion of a field of view of the camera.

9. The system of claim 1, wherein the camera and the position encoder are configured to generate time stamps, the corresponding time stamps associated to positions determined using the position encoder and to images captured by the camera being used to associate images to corresponding positions inside the conduit.

10. A method for inspection of a sewer network, the method comprising the steps of:

moving a cleaning nozzle in a conduit to be inspected, the cleaning nozzle being mounted to a hose, at an end thereof;

inserting a sled having inspection material mounted thereon in the conduit, the inspection material including a camera;

engaging the cleaning nozzle with the sled;

moving the guiding nozzle in the conduit and correspondingly moving the engaged sled in the conduit; and

simultaneously to the sled being moved in the conduit by the movement of the guiding nozzle:

capturing images of the inner wall of the conduit using the camera mounted on the sled; and

acquiring position data through monitoring of the movement of the sled using a position encoder; and

determining a capture position for at least a subset of the images of the inner walls of the conduit captured by the camera, using the position data.

11. The method of claim 10, further comprising the steps of inserting the cleaning nozzle in the conduit through a first manhole and inserting the inspection sled in the conduit via a second manhole.

12. The method of claim 10, wherein the step of acquiring position data through monitoring of the movement sled using a position encoder comprises monitoring the movement of the hose.

13. The method of claim 10, wherein the step of inserting the sled in the conduit comprises the sub steps of:

engaging the sled to a guiding pole;

lowering the sled in the conduit using the guiding pole; and

disengaging the guiding pole from the sled.

14. The method of claim 13, wherein the sub step of engaging the sled to a guiding pole includes activating a pole engaging electromagnet and the sub step of disengaging the guiding pole from the sled includes deactivating the pole engaging electromagnet.

15. The method of claim 10, wherein the step of engaging the cleaning nozzle to the sled includes activating a nozzle electromagnet.

16. The method of claim 15, wherein the step of engaging the cleaning nozzle to the sled includes advancing the nozzle towards the sled and guiding the nozzle using a funnel.

17. The method of claim 10, further comprising the step of removing the sled from the conduit, via the first manhole.

18. The method of claim 17, further comprising the steps of:

simultaneously to the sled being moved in the first manhole:

capturing images of the inner wall of the first manhole using the camera mounted on the sled; and

acquiring position data through monitoring of the movement of the sled using the position encoder; and

determining a capture position for at least a subset of the images of the inner walls of the first manhole captured by the camera, using the position data.

19. The method of claim 10, further comprising the initial step of circulating the cleaning nozzle in the conduit in order to perform cleaning of the conduit.

20. The method of claim 10, further comprising generating time stamps for the captured images of the inner wall of the conduit using the camera and the positions of the position data generated through monitoring of the movement of the sled using the position encoder, and wherein the step of determining a capture position for at least a subset of the images of the inner walls of the conduit captured by the camera comprises using the time stamps to associate images to corresponding capture positions inside the conduit.