Technical field of the invention
[0001] The present invention relates to a device for inspecting defects in a railway, and
more specifically to a device with image capture means configured to simultaneously
acquire at least zenithal images and lateral images of a track of the railway and
with processing means in data communication with the image capture means configured
to receive and process the images acquired by means of an artificial intelligence
model.
Background of the invention
[0002] Safety in rail transport is closely related to the condition of the railway. Some
of the defects that can be found in railways are cracks or breaks in tracks, spalling,
skidding, shelling, squats, corrugations, cracks in the fastenings and sleepers, corrosion
in the metal parts, blows and other anomalies that can cause a catastrophic failure
in the infrastructure. Most defects are found in the tracks, particularly at the head
of the track, however, anomalies can also occur in the web and foot of the track,
which means that it is of the utmost importance to inspect the track in its entirety.
[0003] Traditionally, the state of conservation of railways had to be periodically checked
with visual inspection by railway company personnel; this inspection system not only
requires a lot of personnel and labour time, but also depends on the capacity, training
and experience of each of the individuals responsible for the inspection.
[0004] As an alternative, it is possible to carry out destructive and non-destructive tests
on the elements of the railway, especially the tracks, which are the critical elements
of the infrastructure. Although the tests produce homogeneous, standardised and reliable
results, their great drawback is that they must be carried out by specialised personnel
in laboratories or workshops that have the required equipment, and generally involves
extracting samples of material, which in practice means the loss of the studied section.
[0005] Portable pieces of equipment have also been used to carry out non-destructive tests
that can be transported and used on the same railway, but these processes are considerably
slow, require specialised personnel and only offer a reliable reading of specific
points on the railway, and given the current extension of the railway networks is
unfeasible.
[0006] Obtaining images of the railway for subsequent inspection by an operator has also
been considered; however, after capturing the images, the standards and attention
to detail that the operator must have in front of the monitor when reviewing thousands
of images generates fatigue and loss of concentration that produces false positives
or, even worse, causes him/her to ignore problems due to lack of attention during
viewing.
[0007] With the current increasing rate in railway traffic, carrying ever heavier loads
at higher speeds, a faster, more reliable and more efficient way to inspect railways
is a must. Therefore, there is still a great room for improvement in the field of
railway inspection devices.
Description of the invention
[0008] The present invention proposes a solution to the foregoing problems by means of a
device for inspecting defects in a railway as described below.
[0009] In a first inventive aspect, the invention provides a
device for inspecting defects in a railway, wherein the railway comprises two tracks,
wherein the device for inspecting defects is characterised in that it comprises:
a structure configured to move over the tracks of the railway,
image capture means arranged in the structure and configured to simultaneously acquire
at least zenithal images and lateral images of a track of the railway,
lighting means arranged in the structure and configured to illuminate at least one
track of the railway, and
processing means in data communication with the image capture means, wherein the processing
means are configured to receive and process the images acquired by the image capture
means
wherein the processing means comprise an artificial intelligence model configured
to recognise defects in the railway from the images acquired by means of the image
capture means.
[0010] Throughout this document, a railway will be understood as the railway infrastructure
that enables a railway vehicle to transit, and which comprises, in a conventional
manner, two tracks arranged in parallel at a fixed distance, struts or sleepers to
which the tracks are attached and that help to keep them separated at a fixed distance,
fastenings or attachments to join the rails to the struts; in some cases, the railway
may comprise other elements, such as ballasts, signalling installations, electrification
installations, switches and crossings, etc.
[0011] The structure will be understood as an element formed by one or more portions, the
function of which is to serve as a support and framework for at least some of the
other elements making up the inspection device, which allows the inspection device
to be placed or arranged on the tracks, and which also allows the movement thereof
along the railway as a railway vehicle; in a preferred embodiment, the structure comprises
three or more wheels, with at least two of them arranged in parallel at a distance
corresponding to the track gauge of the railway. In some embodiments, the structure
is configured for adapting the wheelbase to various track gauges.
[0012] The image capture means will also be understood as any technological element capable
of obtaining or capturing images; in a preferred embodiment, the image capture means
comprise digital photographic or video cameras, as well as other auxiliary elements
that allow the operation thereof, such as power supply means or data connection cables.
The image capture means are preferably attached to the structure by means of an articulated
joint, and are oriented such that during normal operation of the inspection device
they allow at least zenithal images of the railway and lateral images of a track to
be simultaneously obtained.
[0013] Zenithal images should be understood as images obtained at a zenithal angle with
respect to the plane of the tracks of the railway, i.e., from a point of view located
vertically and above the plane defined by the tracks; zenithal images show at least
one head of the track, but may show the heads of both tracks, and/or other railway
elements; preferably the zenithal images also show a portion or all of the strut,
sleeper or plate that fulfils these functions. Lateral images of a track are to be
understood as images showing the lateral portion or flank of at least one of the tracks;
preferably, the lateral images show one side of the web of the track, and may also
show attachment elements and other elements of the railway. To obtain lateral images,
an image capture element can be arranged focussing, pointing to or oriented towards
the side of the track.
[0014] Lighting means should be interpreted as one or more light sources capable of providing
lighting in a controlled manner to a section of the railway or to a specific area
of an element of this railway; in a preferred embodiment, the lighting means comprise
one or more lamps oriented such that during normal operation of the inspection device
they illuminate at least the zenithal area and the lateral area of the track.
[0015] Processing means are to be understood as any technological element capable of processing
information, in particular images captured by the image capture means; in a preferred
exemplary embodiment, the processing means are a digital computer arranged in the
structure of the inspection device; in another example, the processing means is a
computer capable of wireless communication that is separated from the structure of
the device. The processing means are in data communication by conventional means,
such as cables or radio frequency communication systems. In addition, the processing
means comprise an artificial intelligence model obtained from an image recognition
algorithm, so that it is capable of recognising different elements in an image of
the railway, as well as detecting anomalies and defects in the elements of the railway,
especially the tracks.
[0016] Advantageously, the inspection device is configured to be arranged on the tracks
of the railway to be inspected like a conventional railway vehicle, capable of moving
along the railway at a constant or approximately constant speed; once arranged or
placed on the rail, the image capture means acquire zenithal images of the railway
and, simultaneously, also acquire lateral images of one or both tracks; this process
can be repeated periodically at regular segments of the rail, between which the inspection
device moves, or it can be carried out continuously, without the device stopping,
depending on the performance of the image capture means. Given that the lighting conditions
of the railway are usually unpredictable and heterogeneous, the lighting means allow
the area of the railway from which the image capture means obtain images to be illuminated
under certain conditions. The images are transmitted to the processing means, which
process them through the artificial intelligence model to detect defects in the railway.
[0017] In a particular embodiment,
the image capture means comprise, for each track of the railway, a camera that is
orientable towards the head of the track, and a camera that is orientable towards
the web of the track. The cameras of the image capture means are arranged such that during the normal operation
of the inspection device they are each oriented, focussed or pointed towards a specific
portion of one of the tracks; in this way, a first camera points to the head of one
track, a second camera points to the web of the same track, a third camera points
to the head of the other track, and a fourth camera points to the web of this other
track. In one embodiment, the cameras pointing to the web of the tracks are oriented
towards the outside faces of the web, providing lateral images of the tracks. Orientable
should be understood as the element being configured to be oriented during the normal
operation of the inspection device towards a specific area of the railway; in one
embodiment, the orientable condition is achieved by means of an articulated joint
between the camera and the structure.
[0018] In a particular embodiment,
the image capture means further comprise two other cameras that are each orientable
to the web of a track of the railway, and one camera that is orientable to the space
between the tracks of the railway. Preferably, the two additional cameras that are orientable to the webs of the tracks
are arranged such that they can focus on the side of the web of the track that is
not focussed on by the previous cameras, for example on the inside faces of the tracks.
For its part, the camera that is orientable to the space between the tracks allows
images to be obtained of both the tracks and one or more of the elements that are
within the angle of focus, such as sleepers, struts and fastenings.
[0019] In a particular embodiment,
the image capture means further comprise one or more cameras that are orientable to
one or more of: a railway strut, a railway attachment, railway ballast, a railway
signalling apparatus. Advantageously, the inspection device comprises additional cameras configured to
obtain images of one or more of the listed elements. This enables specific elements
of the railway to be exclusively or redundantly inspected.
[0020] In a particular embodiment,
the lighting means comprise two lamps, each being orientable to a track of the railway,
and a lamp that is orientable to the space between the tracks of the railway. Advantageously, the lamps enable specific portions of the railway to be illuminated
in a controlled manner so that the images obtained have minimum brightness and contrast
conditions.
[0021] In a particular embodiment,
the device further comprises at least one light detection and ranging, LiDAR, distance
measurement system in data communication with the processing means. With LiDAR systems, accurate distances can be obtained from a set of points to a
reference position, which allows anomalies to be detected in the position of elements
of the railway.
[0022] In a particular embodiment,
the device further comprises positioning means for positioning the device in data
communication with the processing means. Advantageously, the positioning means provide position coordinates of the inspection
device that can be associated with each set of images obtained.
[0023] In a particular embodiment,
the positioning means comprise one or more of: a GNSS satellite navigation module,
a real-time kinematic, RTK, satellite navigation module, an inertial navigation system,
INS. A combination of the foregoing positioning systems allows for improved position reading,
which in turn contributes to a more effective anomaly detection.
[0024] In a particular embodiment,
the device further comprises a self-calibration system configured to detect the metering
of the railway. Advantageously, the self-calibration system allows the correction of possible position
errors of the inspection device.
[0025] In a particular embodiment,
the device further comprises propulsion means configured to propel the device in a
controlled manner. The inspection device can be used to statically inspect a single section of railway,
but its application is more advantageous if the inspection device is moved along a
long segment of railway, which can be achieved by means of an external traction, for
example, by pushing the device along the rail, or more conveniently, by propulsion
means that propel the inspection device at an approximately constant and adjustable
speed. In a preferred embodiment, the device comprises an electric motor operatively
connected to at least one wheel, wherein the motor is powered by lithium batteries.
In another embodiment, the electric motor comprises a controller configured to be
remotely operated by a remote control.
[0026] In a particular embodiment,
the structure comprises at least one telescopic joint configured for adapting the
device to various track gauges. Advantageously, the telescopic joint allows the inspection device to be used in different
types of gauges, from 1400 to 1700 mm; in a preferred embodiment, the structure comprises
fastening systems to secure the track gauge when it is in operation.
[0027] In a particular embodiment,
the processing means comprise a data storage unit. Advantageously, the data storage unit allows non-transitory storage of the images
obtained by the image capture means together with additional data, such as the date
and time of acquisition and the coordinates of the place where it was acquired. This
information can be used as a log for later reference.
[0028] These and other features and advantages of the invention will be evident in light
of the description of preferred, but not exclusive, embodiments which are illustrated
by way of non-limiting example in the drawings which are attached.
Brief description of the drawings
[0029]
- Figures 1a, 1b
- show a preferred embodiment of the inspection device, from two different angles.
Detailed description of an exemplary embodiment
[0030] In the following detailed description, numerous specific details are set forth in
the form of examples to provide a thorough understanding of the relevant teachings.
However, it will be apparent to those skilled in the art that the present teachings
can be implemented without such details.
[0031] Figures 1a and 1b show a preferred exemplary embodiment of the device (1) for detecting
defects in a railway from two different points of view. In the embodiment shown, the
detection device (1) is built around a structure (2) or chassis formed by a set of
structural aluminium profiles; in other embodiments, the structure (2) is formed using
3D printing with SLS technology with polyamide-glass fibre (PA-GF) reinforced powder
material.
[0032] The structure (2) of the example is configured as a beam that is placed on the tracks
of the railway to be inspected, substantially perpendicular to the axis of the rail;
the structure (2) rests on the tracks by means of two wheels mounted at the ends of
a crossbar arranged at one end of the beam, and by means of a set of two wheels in
tandem arranged at the opposite end of the beam. A set of profile segments serves
to join the different means and elements of the device (1) to the structure (2).
[0033] In some examples, the beam comprises two portions joined by means of a telescopic
joint that enables the wheelbase to be selectively modified, so that it can be adapted
to different track gauges. In a particular example, the structure (2) comprises locking
elements that allow the telescopic joint to be interlocked and the position of the
device (1) to be locked in track gauges of 1400 mm or 1700 mm during operation.
[0034] In the embodiment described, the image capture means (3) comprise seven digital cameras,
with three cameras focussing on each track from three different angles, and another
focussing on the space between the tracks; for each track there is a camera in a zenithal
position with respect to the track, and two cameras oriented to the sides of the track,
one focussing on the outside face of the web of the track, and another camera focussing
on the outside face of the web of the track. In the example shown, the cameras are
mounted by articulated joints at the ends of prismatic profiles that are joined to
the beam of the structure (2). The cameras can work continuously as video cameras,
or acquiring images at regular time intervals, in a discreet manner.
[0035] To ensure that the images have homogeneous brightness and contrast conditions, the
device comprises lighting means (4) that in the example are implemented by means of
three pairs of lamps, one pair for each track, and another pair focussing on the space
between the tracks. In the example shown, the lamps are mounted on some of the profiles
that support the cameras.
[0036] The acquired images are transmitted by cables to the processing means (5) which in
this example are made up of a computer; this computer is powered by rechargeable lithium
batteries and comprises a data storage unit in which the acquired images are stored
for later reference; in this example, the data storage unit is a conventional hard
drive. In some examples, the computer further comprises wireless communication means,
for example wireless communication means capable of connecting to a data network.
[0037] In this example, the device (1) comprises positioning means (6), which comprise a
GPS module and an odometer; the positioning means (6) provide the current coordinates
of the device (1) at the time the images of the railway are acquired, and they are
stored together with them. In other examples, the positioning means (6) comprise other
systems or modules that offer a reading of the position of the device (1) on the railway,
such as satellite navigation modules, GNSS, systems other than the GPS system, real-time
kinematic satellite navigation modules, or RTK, or inertial navigation systems, INS.
[0038] In the example described, the computer comprises an artificial intelligence model
configured to identify the elements that make up the railway in the images and to
detect anomalies or defects in them. The artificial intelligence model is obtained
through a process of training an image recognition algorithm with a set of labelled
images of railways, including images with anomalies and images with the railway in
good condition. This model allows, firstly, identifying each of the elements of the
railway that appear in the image, and secondly, locating possible anomalies or defects
in real time; given the reading of the positioning means (6), the presence of anomalies
is associated with a specific position of the railway to facilitate its inspection
and validation by qualified personnel. In one example, the artificial intelligence
model provides an assessment of the severity of the anomaly, for example, the length
of a crack in a strut; the assessment can be represented, for example, by means of
a colour mask superimposed on the anomaly in the image. In other embodiments, the
computer transmits the images via a data network to another computer that comprises
the artificial intelligence model and executes the described image analysis.
[0039] In this example, the device (1) further comprises a LiDAR system, not shown in the
figures, which allows the dimensions of the elements of the railway to be accurately
calculated, and to determine whether there is any deformation that exceeds the tolerance
limits.
[0040] It also comprises a self-calibration system; by detecting the rail metering placed
in the web of the track, an image capture system is arranged that allows the device
(1) to be repositioned on the rail, eliminating possible errors accumulated by the
positioning means (6) between metering marks.
[0041] To propel the device (1), it comprises propulsion means (7), implemented by means
of an electric motor that transmits power to the wheels arranged at the end of the
beam. The propulsion means (7) in this example can be controlled remotely by a remote
control that allows the personnel responsible for its operation to establish a constant
speed.
1. A device (1) for inspecting defects in a railway, wherein the railway comprises two
tracks, wherein the device (1) for inspecting defects is
characterised in that it comprises:
a structure (2) configured to move over the tracks of the railway,
image capture means (3) arranged in the structure (2) and configured to simultaneously
acquire at least zenithal images and lateral images of a track of the railway,
lighting means (4) arranged in the structure (2) and configured to illuminate at least
one track of the railway, and
processing means (5) in data communication with the image capture means (3), wherein
the processing means (5) are configured to receive and process the images acquired
by the image capture means (3);
wherein the processing means (5) comprise an artificial intelligence model configured
to recognise defects in the railway from the images acquired by the image capture
means (3).
2. The device (1) for inspecting defects according to the preceding claim, wherein the
image capture means (3) comprise, for each track of the railway, a camera that is
orientable towards the head of the track, and a camera that is orientable towards
the web of the track.
3. The device (1) for inspecting defects according to the preceding claim, wherein the
image capture means (3) further comprise two other cameras that are each orientable
to the web of a track of the railway, and one camera that is orientable to the space
between the tracks of the railway.
4. The device (1) for inspecting defects according to any of claims 2-3, wherein the
image capture means (3) further comprise one or more cameras that are orientable to
one or more of: a railway strut, a railway attachment, railway ballast, a railway
signalling apparatus.
5. The device (1) for inspecting defects according to any of the preceding claims, wherein
the lighting means (4) comprise two lamps, each being orientable to a track of the
railway, and a lamp that is orientable to the space between the tracks of the railway.
6. The device (1) for inspecting defects according to any of the preceding claims, wherein
the device (1) further comprises at least one light detection and ranging, LiDAR,
distance measurement system in data communication with the processing means (5).
7. The device (1) for inspecting defects according to any of the preceding claims, wherein
the device further comprises positioning means (6) of the device (1) in data communication
with the processing means (5).
8. The device (1) for inspecting defects according to the preceding claim, wherein the
positioning means (6) comprise one or more of: a GNSS satellite navigation module,
a real-time kinematic, RTK, satellite navigation module, an inertial navigation system,
INS.
9. The device (1) for inspecting defects according to any of the preceding claims, wherein
the device (1) further comprises a self-calibration system configured to detect the
metering of the railway.
10. The device (1) for inspecting defects according to any of the preceding claims, wherein
the device (1) further comprises propulsion means (7) configured to propel the device
in a controlled manner.
11. The device (1) for inspecting defects according to any of the preceding claims, wherein
the structure (2) comprises at least one telescopic joint configured for adapting
the device (1) to various track gauges.
12. The device (1) for inspecting defects according to any of the preceding claims, wherein
the processing means (5) comprise a data storage unit.