EP4244117A1

EP4244117A1 - Method and mobile measuring system for measuring an infrastructure component, in particular a track structure component

Info

Publication number: EP4244117A1
Application number: EP21805490.6A
Authority: EP
Inventors: Markus Pröll
Original assignee: Plasser und Theurer Export Von Bahnbaumaschinen GmbH
Current assignee: Plasser und Theurer Export Von Bahnbaumaschinen GmbH
Priority date: 2020-11-11
Filing date: 2021-11-03
Publication date: 2023-09-20
Also published as: WO2022101061A1; AT524402A1

Abstract

A method for measuring an infrastructure component (1), in particular a track structure component, comprises the steps of: providing a mobile measuring system (2) having a stereo camera (11), arranging the measuring system (2) on the infrastructure component (1), capturing at least one pair of images from the infrastructure component (1) by means of the stereo camera (11), determining a relative position of at least one measurement point (37, 38, 39, 40, 41) coupled to the infrastructure component (1) on the basis of the at least one pair of images, and determining a deformation of the infrastructure component (1) on the basis of the at least one relative position and/or detecting a measurement position of the measuring system (2) in a global coordinate system (30).

Description

Method and mobile measuring system for measuring an infrastructure component, in particular a track structure component

The invention relates to a method for measuring an infrastructure component, in particular a track structure component. Furthermore, the invention relates to a mobile measuring system for measuring an infrastructure component, in particular a track structure component.

A method and a measuring system for optically detecting fixed points next to a track are known from AT 518579 A1. The measuring system is arranged on a measuring car that can be moved on a track and includes a stereo camera system for capturing image pairs of the lateral surroundings of the track. The position of fixed points in the area is determined by means of the pairs of images, from which the position of the measuring vehicle can be deduced. Based on the determined position of the measuring carriage, a drift correction of position data is carried out, which is determined with an inertial measuring device.

It is an object of the invention to provide an improved method for measuring an infrastructure component, in particular a track structure component, which can be carried out very economically, can be used flexibly and is precise with regard to the measurement results.

This object is achieved by a method having the features of claim 1. It was recognized that an infrastructure component can be measured in a particularly precise, economical and flexible manner using a mobile measurement system with a stereo camera. Determining the deformation of the infrastructure component based on the at least one relative position makes it possible to draw conclusions about the stress on the Infrastructure component, especially during transport and / or in the installed state to pull. The detection of the measurement position of the measurement system in the global coordinate system ensures a particularly precise determination of the arrangement of the infrastructure component in the global coordinate system. The pair of images can be recorded without contact, in particular if the measuring system is arranged at a distance from the infrastructure component. The attachment of measuring equipment to the infrastructure component can largely, in particular completely, be dispensed with. The accessibility of the infrastructure component can therefore remain unaffected during the measurement process. The measurement of the infrastructure component from a distance also enables a more flexible choice of the arrangement of the mobile measurement system, so that it can be reliably arranged on a solid surface. Measuring the infrastructure component by means of image acquisition allows the precise measurement of both small infrastructure components, for example with a main dimension of a maximum of 2 m, and very large infrastructure components, for example with a main dimension of at least 5 m, in particular at least 10 m, in particular at least 100 m. In particular the relative position of several measuring points can be determined using a single pair of images. The method can be carried out fully automatically. In the case of an at least partially manual measurement, the method offers a high degree of safety for the measurement personnel due to the arrangement at a distance from the infrastructure component. The method is particularly suitable for use in safety-critical areas such as construction sites, on busy traffic routes and/or on contaminated infrastructure components.

The relative position of the at least one measuring point in three-dimensional space, in particular in a camera Coordinate system to be determined. The depth of the at least one measuring point can be determined on the basis of the pair of images, in addition to the two-dimensional information of the respective individual image. This depth can be determined based on the angle and the distance between the cameras of the stereo camera. The individual images of the image pair are preferably captured at the same time. The methods for determining the position of a measurement point in three-dimensional space using a pair of images are known from the prior art.

The infrastructure component is understood to mean a structural component from the construction industry, in particular from the transport sector. The infrastructure component can be a component from building construction, in particular building construction, for example a building wall, and/or from civil engineering, in particular bridge construction, for example a bridge girder or a bridge pillar, tunnel construction, pipeline construction, mining, road construction and/or the Track construction, for example a track structure component. The infrastructure component preferably comprises a precast concrete component, in particular a precast concrete slab, for example a precast concrete slab for constructing a track without sleepers, or a precast concrete girder. In particular, the infrastructure component can be a road element and/or a track element, in particular made of ready-mixed concrete. A main dimension of the infrastructure component, in particular an area that can be detected, in particular an area that can be recorded using the stereo camera, of the infrastructure component is preferably at least 1 m, in particular at least 5 m, in particular at least 10 m, in particular at least 20 m, in particular at least 50 m and/or at most 100 m, in particular a maximum of 50 m, in particular a maximum of 20 m, in particular a maximum of 10 m, in particular a maximum of 1 m. The main dimension is understood to mean the maximum dimension of the infrastructure component. The mass of the infrastructure component is preferably in a range from 50 kg to 500 t, in particular from 0.5 t to 150 1, in particular from 1 1 to 100 1, in particular from 5 t to 50 t.

Measuring the infrastructure component means in particular determining the arrangement and/or the deformation of the infrastructure component. The deformation can include stretching and/or twisting and/or distortion of the infrastructure component. The arrangement of an object includes its position and orientation. A mobile object is understood to mean that it is designed to be movable, that is to say transportable, in particular portable. For portability of the object, in particular the measuring system, its mass is preferably a maximum of 50 kg, in particular a maximum of 20 kg.

A stereo camera is understood to mean an image acquisition unit which enables images to be recorded from two different positions, in particular simultaneously. For this purpose, the stereo camera can have two cameras arranged at a distance from one another and/or a single camera with a mirror device for capturing image halves from positions at a distance from one another. In principle, the pair of images can also be recorded using a single camera, which is successively shifted into two mutually spaced positions in order to record the individual images. The distance between these objected positions must be detectable in order to determine the depth of the at least one measuring point. If this is the case, this can also be understood as a stereo camera. The at least one camera is preferably designed as a digital camera, in particular as a full HD camera. The at least one camera is preferably designed to record images with a resolution in a range from 1 MP (megapixel) to 64 MP, in particular from 4 MP to 32 MP, in particular from 8 MP to 16 MP. The at least one measuring point can be a point on the surface of the infrastructure component and/or the center of a partial area of the infrastructure component and/or a point, in particular the center, of an object coupled to the structural component, in particular a marking. The marking is preferably attached rigidly to the infrastructure component. According to one aspect of the invention, the marking is movably, in particular linearly displaceable, attached to the infrastructure component. This advantageously means that the infrastructure component can be measured in detail using a plurality of image pairs with different arrangements of the at least one marking relative to the infrastructure component.

Using the measurement system, individual measurement points coupled to the infrastructure component can be recorded and/or at least sections of a surface of the infrastructure component or an object coupled thereto. The relative position of the at least one measuring point can be inferred from the detected surface. The relative position is preferably determined by evaluating partial areas, so-called facets, of the detected surface.

The global coordinate system is preferably a geographic coordinate system. The global coordinate system can be determined by the coordinate system in which the position of survey points for land surveying are specified. Points specified in the global coordinate system are preferably uniquely determined with regard to their global position. The relative position is understood to mean the position of the respective measuring point in a local coordinate system, in particular in a camera coordinate system. The origin of the camera coordinate system is preferably in the middle between the two individual cameras. The x axis of the camera coordinate system is preferably oriented horizontally and points in the viewing direction of the stereo cameras. The z axis of the camera coordinate system preferably points upwards in the vertical direction. The y-axis of the camera coordinate system results from the formation of the camera coordinate system as a right-hand Cartesian coordinate system.

According to one aspect of the invention, the relative position and/or the measurement position and/or the component position can be determined by means of the measurement system with a measurement deviation of at most 100 mm, in particular at most 10 mm, in particular at most 1 mm, in particular at most 0.1 mm, in particular at most 0.01 mm, in particular a maximum of 0.001 mm.

A distance between the measuring system, in particular the stereo camera, and the infrastructure component can be at least 1 m, in particular at least 5 m, in particular at least 10 m, in particular at least 20 m, in particular at least 50 m, in particular at least 100 m, in particular at least 250 m, and/or a maximum of 100 m, in particular a maximum of 50 m, in particular a maximum of 20 m, in particular a maximum of 10 m, in particular a maximum of 2 m. The measuring system can thus be positioned particularly flexibly and the measuring field that can be recorded by the stereo camera is particularly large. The field of view of the stereo camera is determined by the overlapping area of the fields of view of the two digital cameras. The measurement system preferably includes an illumination unit for illuminating the infrastructure component. The lighting unit can be designed to emit infrared light and/or UV light and/or narrow-band blue light and/or white light. The lighting device can also be designed to project a pattern, in particular a grid, onto the infrastructure component. The lighting unit preferably has at least one LED and/or a projector as the light source. Such an illumination unit advantageously ensures that the acquisition of the at least one pair of images is particularly robust with respect to environmental influences.

The measurement arrangement, in particular the measurement position and/or the measurement orientation, of the measurement system is preferably determined in the global coordinate system. The measurement arrangement is preferably described by the arrangement of a measurement coordinate system. The measurement position corresponds to the origin of the measurement coordinate system and the measurement orientation corresponds to the orientation of the measurement coordinate system. The arrangement of the measuring system can preferably be reversibly fixed by means of a fixing unit. The fixing unit preferably has a tripod, in particular a tripod. The fixing unit enables the measurement arrangement to be stably fixed in the global coordinate system. A vertical axis of the measurement coordinate system is preferably aligned by means of the fixing unit in such a way that it points upwards in the vertical direction.

The infrastructure component is preferably measured in a fixed arrangement, in particular in a fixed measurement position and/or Measurement orientation of the measurement system, in particular in the global coordinate system. The arrangement of the measuring system is preferably retained for the period in which the infrastructure component, in particular in the target component arrangement, is relocated and/or in which at least two, in particular at least five, in particular at least ten, of the image pairs of the infrastructure component are captured by the stereo camera . The infrastructure component can thus be measured in a particularly robust and precise manner.

The measurement position and/or the measurement orientation can deviate from or coincide with the camera position and/or the camera orientation. The stereo camera is preferably mounted on the fixing unit so that it can swivel about the vertical axis and/or a horizontal axis, in particular with respect to the measuring coordinate system. As a result, the camera orientation can be changed relative to the measurement orientation. The orientation of the camera coordinate system relative to the measurement coordinate system is preferably detected by means of at least one angle sensor, in particular a rotary encoder. The position of the origin of the camera coordinate system relative to the origin of the measurement coordinate system can be specified unchanged by a connection s structure or be changeable and measurable by means of at least one sensor. As a result, a measurement camera vector can be determined between the origin of the measurement coordinate system and the origin of the camera coordinate system. By detecting the measuring camera vector and/or the orientation of the stereo camera relative to the measuring coordinate system, it is advantageously achieved that the relative position of the respective measuring point detected by means of the stereo camera, in particular independently of the arrangement of the stereo camera in the measuring -Coordinate system, is determinable. A method according to claim 2 enables the component arrangement to be described in a uniform, stationary and/or standardized reference coordinate system. The component arrangement includes the component position and/or the component orientation. The component position is preferably described by the origin of a component coordinate system. The component orientation can be described by the orientation of the component coordinate system. The component arrangement can be determined based on the at least one relative position, in particular based on at least two, in particular at least three, relative positions, based on common geometric functions, in particular in the camera coordinate system. The arrangement of components in the global coordinate system is preferably calculated on the basis of the arrangement of components in the camera coordinate system using common calculation methods for coordinate transformation.

The deviation of the component arrangement from a target component arrangement can be determined using the method according to claim 3 . In particular, the deviation of the component position and/or the component orientation from a target component position and/or target component orientation can be determined. The comparison result can be calculated using the difference between the component arrangement and the target component arrangement. The result of the comparison is a measure of the extent to which the current component arrangement deviates from the target component arrangement.

A method according to claim 4 ensures a particularly precise arrangement, in particular positioning and orientation, of the infrastructure component. The relocation of the infrastructure component can be be done manually, in particular by hand, or automatically with the same result. The infrastructure component can be relocated by means of a transport device, in particular by means of a rail vehicle and/or a road vehicle and/or a track-laying device and/or a construction crane.

The infrastructure component is preferably measured, in particular repeatedly, during the relocation, in particular from a storage arrangement, to the target arrangement. As a result, a course, in particular a change, of the deviation of the component arrangement from a target component arrangement can be determined. The shifting of the infrastructure component, in particular into the desired component arrangement, can be controlled, in particular regulated, on the basis of this course.

A method according to claim 5 is particularly robust in operation and has an expanded field of application. The pairs of images can be captured at times that follow one another periodically or aperiodically. A mean value is preferably formed over at least two, in particular at least three, in particular at least five, and/or a maximum of ten of the relative positions recorded using the image pairs at different points in time. This redundancy makes the measurement process particularly precise. The image pairs can be recorded, for example, at an interval of at least one month, in particular at least one year and/or a maximum of 20 years, in particular a maximum of 10 years, in particular a maximum of 5 years, and/or after a specified maintenance period has expired. A comparison result is preferably obtained by comparing the component arrangement at the different time definitely score. This comparison result can be used to draw conclusions about the change in the component arrangement. On this basis, the need for maintenance measures can be determined.

A method according to claim 6 ensures that the infrastructure component is measured and/or arranged in a particularly efficient manner. The movement path of the at least one measuring point is preferably a trajectory in three-dimensional space. The movement path can include the measurement points determined at different points in time, in particular consist of them, and/or be supplemented by interpolation between the measurement points to form an uninterrupted line. The movement path can be determined when the infrastructure component is relocated relative to the global coordinate system and/or when the at least one measuring point, in particular the at least one marking, is relocated relative to the infrastructure component. For example, the component arrangement can be shifted particularly efficiently into the target component arrangement using the movement path, in particular on the basis of a control with an integral and/or differential control element. In the case of a measuring point that is shifted relative to the infrastructure component, the component arrangement and/or the component geometry can be determined particularly efficiently and precisely using the movement path.

For example, the at least one measuring point, in particular a marking, can be arranged on a measuring carriage for displacement on a track. The position of the at least one measurement point relative to the rails can be fixed or recorded. By determining the relative position of the at least one measuring point coupled to the rails via the measuring carriage, the geometry and the arrangement of the infrastructure components designed as rails can be determined. A method according to claim 7 can be used particularly flexibly and is economical to operate. The image pairs are preferably recorded with a measurement frequency in a range from 0.01 Hz to 500 Hz, in particular from 0.1 Hz to 250 Hz, in particular from 1 Hz to 150 Hz, in particular from 10 Hz to 100 Hz. The mean value is preferably formed over the relative positions recorded using the image pairs recorded with a corresponding frequency.

A method according to claim 8 ensures that the measurement position is determined in a particularly simple and precise manner. The survey point is understood to mean a fixed point firmly marked on the ground or on a building, which serves in particular as a starting point or as a target point in land surveying. The measurement position is preferably determined after the arrangement of the measurement system has been determined by means of the fixing unit. The measurement arrangement, in particular the measurement position and/or the measurement orientation, of the measurement system is preferably determined in the global coordinate system. For this purpose, the measuring system can have a position determination unit, in particular a satellite navigation module, in particular a GPS module, a Galileo module and/or a Glonass module, and/or a tachymeter for geodesy, in particular a laser distance measuring device. The measurement arrangement can be determined by laser distance measurement and triangulation of the measurement points and/or using the satellite navigation signal of the GPS module, the Galileo module and/or the Glonass module.

A method according to claim 9 can be used particularly flexibly and carried out efficiently. The camera arrangement, in particular the camera position and/or the camera orientation, is preferably related to the measuring arrangement, in particular the measurement position and/or the measurement orientation, rigid or changeable. The camera arrangement relative to the measurement arrangement can be determined in a calibration process, in particular in the case of a rigid connection. The camera arrangement is preferably changed, in particular pivoted, between two consecutively captured image pairs relative to the fixing unit. The relative arrangement of the stereo camera with respect to the fixing unit can be detected automatically with the aid of the angle sensor and/or the displacement sensor. Alternatively, this relative arrangement can be recorded manually. This advantageously means that the arrangement of the fixing unit can be retained if a rearrangement, in particular a reorientation of the stereo camera, is required for measuring the infrastructure component. The component arrangement of the infrastructure component can also be determined after rearranging the stereo camera in the global coordinate system without the need for rearranging the measurement system. Thus, for example, a measuring point that has moved beyond the measuring field of the stereo camera can be tracked by panning the stereo camera.

A method according to claim 10 enables an analysis of the stress on the infrastructure component. At least two, in particular at least three, of the relative positions are preferably compared with a respective reference value. The at least one reference value can be a reference position specified for the respective relative position. The reference position can take place, for example, in the course of a reference measurement, in particular of the unloaded infrastructure component. It is preferably checked whether the deviation of the at least one relative position from the respective reference value exceeds a predefined deformation threshold value. The deformation threshold value preferably correlates with an allowable deformation of the infrastructure component. The at least one relative position is preferably compared with the respective limit value while the infrastructure component is being relocated, in particular to the target component arrangement, and/or before or after the infrastructure component is fixed in the target component arrangement and/or after a maintenance period has expired. This enables the stress on the infrastructure component to be monitored, which increases the operational reliability of the infrastructure component and enables maintenance and repair work on the infrastructure component to be carried out particularly efficiently and economically.

According to one aspect of the invention, the deformation of the infrastructure component is determined by comparing at least three, in particular at least ten, in particular at least 100, in particular at least 500, in particular linearly independent and/or distributed in a grid over a surface of the infrastructure component, relative positions with at least one, in particular one each, reference value. This advantageously means that local deformations of the infrastructure component can also be detected.

A method according to claim 11 ensures the particularly precise determination of the deformation of the infrastructure component. The geometry model can be a CAD model. The structural model can be an FEM model. The at least one pair of reference images can have been captured of the infrastructure component in an unloaded state and/or the fixing of the infrastructure component in the desired component arrangement and/or after a maintenance period has expired. The reference value and/or the deformation threshold value can be determined using a structural model, in particular an FEM model, in particular under virtual loading of the infrastructure component with loads, in particular with the loads to be expected when the infrastructure component is in use. For example, the deformation threshold value for the respective deviation of the relative position from the reference value can be determined using the structural model as the maximum permissible stress on the infrastructure component. The stress on the infrastructure component in relation to a permissible stress can thus be determined on the basis of the result of the comparison between the respective reference value and the relative position.

A method according to claim 12 makes stresses, in particular overstresses, of the infrastructure component during transport recognizable. The monitoring of the deformation of the infrastructure component during displacement preferably takes place periodically, in particular with the measurement frequency described above. This reliably prevents brief peak deformations, in particular load peaks, from remaining undetected.

According to one aspect of the invention, the deformations determined are documented, in particular stored in the memory element of an evaluation unit. The deformation information is preferably stored in a database for life cycle monitoring of the respective infrastructure component.

Based on the at least one relative position, in particular based on the comparison of the at least one relative position with the at least one reference value, stresses on the infrastructure component Based on a structural model, in particular an FEM model, are calculated. For example, stresses in the infrastructure component can be determined based on the at least one relative position.

A method according to claim 13 enables the stresses acting on the infrastructure component during relocation to be reduced. For example, based on the result of the comparison, the displacement can be influenced in such a way that a threshold value of the deformation is not exceeded. A controlled displacement of the infrastructure component preferably takes place on the basis of the deformation in such a way that the deformations are minimized.

The infrastructure component can in particular be measured in real time. This means that the time between the image acquisition and the determination of the at least one relative position is a maximum of 1 s, in particular a maximum of 0.1, in particular a maximum of 0.01 s. As a result, the arrangement of the infrastructure component can be controlled, in particular regulated, in a particularly efficient manner.

A method according to claim 14 enables a particularly detailed measurement of the infrastructure component. Preferably, relative positions of at least two measuring points, in particular for monitoring a linear extent, the component position and/or the component orientation, in particular of at least three measuring points, in particular for monitoring a curvature of the infrastructure component, in particular of at least four, in particular at least five, in particular at least ten, in particular at least 50, in particular at least 100, in particular at least 1000 measuring points. A method according to claim 15 can be carried out particularly robustly and reliably. The at least one marking can be rigidly or movably coupled to the infrastructure component, in particular linearly displaceable. The marking can have a reflector for reflecting light. The marking preferably includes a connecting means for the precise positioning on the infrastructure component. According to one aspect of the invention, the marking is attached to a predetermined position of the infrastructure component. The marking can have a pattern for easier and/or automated identification of the marking. The marking, in particular the pattern, preferably includes unique identification information. The unique identification information is preferably assigned to an individual measurement point. In this way, an in particular automated assignment of the recorded relative position to the respective measuring point can take place. The method can thus be implemented in a particularly reliable and robust manner with respect to operating errors. By coupling the at least one, in particular visual, marking, the infrastructure component can be measured particularly precisely. Such markings are also referred to as measuring marks.

A further object of the invention is to create a mobile measuring system for measuring an infrastructure component, in particular a track structure component, which can be used very economically and flexibly and provides particularly precise measurement results.

This task is solved by a mobile measuring system with the features of claim 16 . The advantages of the mobile measuring system correspond to the advantages of the method described above. Especially the mobile measuring system can be further developed with at least one of the features that are described above in connection with the method.

The evaluation unit preferably includes a processor for processing digital data, in particular in real time, and/or a storage element for storing the data and/or a user interface for exchanging information with the user. There is preferably a signal connection, in particular a cable connection, between the evaluation unit and the stereo camera. The evaluation unit preferably includes a desktop PC, a notebook and/or a tablet PC and/or a smartphone.

The mobile measuring system is preferably designed to carry out the method described above. A computer program for executing the method described above can be stored on the memory element of the evaluation unit.

The invention also relates to a computer program for carrying out the method described above.

The mobile measuring system preferably includes a fixing unit for determining the arrangement of the measuring system, in particular for fixing the measuring system on the ground. The fixing unit can include a tripod and/or a carriage, in particular a measuring carriage that can be moved on rails. The fixing unit is preferably designed to completely determine the measurement position and/or the measurement orientation of the measurement system. This allows the determination of the relative position, in particular the determination of the arrangement of the infrastructural component in the global coordinate system, be carried out particularly precisely and robustly.

A mobile measuring system according to claim 17 is particularly flexible and economical to operate. The measuring means can be designed to detect the camera position and/or the camera orientation relative to the measuring position and/or the measuring orientation. The measuring means can be designed for analog or digital detection of the camera arrangement. The evaluation unit is preferably designed for the automated detection of the camera arrangement relative to the measuring arrangement by means of the measuring means. The measuring means can have at least one angle sensor for detecting the camera orientation relative to the measurement orientation and/or a displacement sensor for detecting the camera position relative to the measurement position. The angle sensor is preferably designed as a rotary encoder on a swivel joint between the stereo camera and the fixing unit and/or the position determination unit. The path sensor can be designed as a linear guide between the stereo camera and the fixing unit. The evaluation unit is preferably designed to capture the camera arrangement relative to the measurement arrangement when capturing the image pair of the infrastructure component. The stereo camera can thus be moved, in particular pivoted, in order to track a measurement point displaced over the measurement field of the stereo camera. The position of the measurement point can thus always be calculated in the measurement coordinate system and/or in the global coordinate system even if the stereo camera is displaced. The measuring field of the measuring system is thus significantly larger than the measuring field of the stereo camera. Further features, details and advantages of the invention result from the following description of several exemplary embodiments with reference to the figures. Show it:

1 shows a schematic representation of a mobile measuring system with a stereo camera, an evaluation unit and a position determination unit, the measuring system being used to measure a structural track component, in particular a precast concrete slab for the construction of a sleeper-free track,

2 shows a plan view of the measuring system in FIG. 1, wherein measuring points detected by the stereo camera and coupled to the infrastructure component and measuring points detected by the position determination unit are shown together with a global coordinate system, a measuring coordinate system and a camera coordinate system,

3 shows a perspective representation of the measuring system and the infrastructure component in FIG.

4 shows a schematic representation of the mobile measuring system in FIG. 1, the measuring system being used for measuring a building element, 5 shows a schematic representation of the mobile measuring system in FIG.

6 is a perspective view of the measurement system of FIG. 1, the measurement system being used to measure rails by detecting the path of movement of measurement points moved relative to the track.

A first exemplary embodiment of a method for measuring an infrastructure component 1 using a mobile measuring system 2 is described with reference to FIGS. 1 to 3 . The infrastructure component 1 is a structural track component, in particular a precast concrete slab for constructing a track 3 without sleepers. The infrastructure component 1 has support elements 5 for fastening rails 4 . Bores 6 for attaching tension clamps 7 are arranged on the support elements 5 .

Surveying points 8 are located in the vicinity of the measuring system 2 or the infrastructure component 1. Surveying points 8 are points fixed on the ground or on buildings, which serve as starting or target points in land surveying or in construction. Reflector rods 9 placed in the survey points 8 are used to detect the position of the survey points 8 . The reflector rods 9 can be detected by sensors in a particularly simple and reliable manner. A reflector rod 9 usually comprises an optically detectable target window 10 which is arranged vertically above the survey point 8 at a specific distance therefrom in order to detect it. The measuring system 2 has a stereo camera 11 and a position determination unit 12 . In order to set up the measuring system 2 stably on the floor, the measuring system 2 comprises a tripod 13, in particular a tripod. Furthermore, the measuring system 2 includes an evaluation unit 14 for processing the data recorded by the stereo camera 11 and the position determination unit 12 .

The position determination unit 12 is attached to the tripod 13 . A vertical axis 15 of the position determination unit 12 can be aligned vertically by means of the stand 13 . A laser distance measuring device 16 of the position determination unit 12 is attached to the stand 13 so as to be pivotable about a horizontal axis 18 via a horizontal joint 17 and about a vertical axis 20 via a vertical joint 19 . The two joints 17, 19 are each formed with a rotary encoder 20a, 20b, not shown, for detecting the orientation of the laser distance measuring device 16. The orientation of the laser distance measuring device 16 can be completely determined by means of these rotary encoders 20a, 20b and due to the vertical alignment of the vertical axis 15.

The laser distance measuring device 16 is designed to detect a reflector distance bi, b, bs from the measurement points 8, in particular from the target window 10 of the reflector rods 9. In order to align the laser distance measuring device 16 in the direction of the respective target window 10, it can be pivoted about the joints 17, 19. The detected reflector distances bi, bi, bs can be transmitted to the evaluation unit 14 via a signal connection 21 together with the angles of rotation βi, βi, βs, yi, yi, y3 detected by the rotary encoders 20a, 20b. The stereo camera 11 has two digital cameras 22 . The digital cameras 22 are arranged at a camera distance D from one another. In particular, the two digital cameras 22 are arranged at the same height in the vertical direction. The stereo camera 11 is connected to the position determination unit 12 in such a way that it can be pivoted about the vertical axis 20 by means of the vertical joint 19, but not about the horizontal axis 18. The orientation of the stereo camera 11 relative to the tripod 13 can only be adjusted about the vertical axis 20. The digital cameras 22 are full HD cameras with a resolution of 1920x1080 pixels.

The measuring system 2 has an illumination unit 23 . The lighting unit is arranged centrally between the digital cameras 22 . In order to reduce the influence of extraneous light, the lighting unit 23 is designed to emit infrared light.

Markings 24 in the form of reflectors are coupled to the infrastructure component 1 . The respective marking 24 is attached to the infrastructure component 1 , in particular to the bores 6 , by means of a marking attachment 25 .

The markings 24 are arranged offset by marker vectors Ci, Ci, C3, C4, C5 in relation to the stereo camera 11, in particular in relation to an origin 26 of a camera coordinate system 27. The distances between the reflectors bi, b, b3 are determined relative to the origin 28 of a measuring coordinate system 29 of the measuring system 2. A global coordinate system 30 has the origin 31. The evaluation unit 14 includes a processor 32 for processing data, a user interface 33 for exchanging information with the user and a storage element 34 for storing digital data. The processor 32 is in signal connection with the measuring system 2 , with the user interface 33 and the memory element 34 via the signal connection 21 . The user interface 33 has a touch-sensitive screen. The evaluation unit 14 can be a desktop PC, a laptop, a tablet PC or a smartphone, for example.

The functioning of the measuring system 2 is as follows:

To build the track 3, the infrastructure components 1 in the form of precast concrete slabs are continuously applied to one another. For this purpose, in particular, the infrastructure components 1 are successively shifted from a transport position to an individual target component position. In the target component position, the respective infrastructure component 1 is preferably arranged in a target component orientation. The infrastructure component 1 can be moved, for example, by means of a crane 35 . The measuring system 2 is used for the precise, planned positioning and orientation of the infrastructure component 1 .

The measuring system 2 is arranged on the infrastructure component 1 in such a way that the measuring field 36 of the stereo camera 11, in particular an overlapping area of fields of view of the two digital cameras 22, overlaps the infrastructure component 1 and the markings 24 coupled to it, at least in the target component position. This ensures that both digital cameras 22 can see the infrastructure component 1 and the markings 24 attached to it when the infrastructure component 1 is arranged. can grasp. The vertical axis 15 of the measuring system 2 is aligned vertically by means of the tripod 13, in particular by means of an analog or digital spirit level. The stand 13 is fixed to the ground and also no longer moves in the course of the subsequent measurement process.

The measuring coordinate system 29 is rigidly connected to the fixing unit 13 or fixed by the fixing unit 13 and is thus fixed in relation to the global coordinate system 30 . The measurement position of the measurement system 2, in particular the origin 28 and the orientation of the measurement coordinate system 29, in the global coordinate system 30 are determined. For this purpose, the reflector rods 9 are arranged on the measurement points 8 located in the vicinity of the measurement system 2 . The laser distance measuring device 16 is successively aligned with the respective target windows 10 of the reflector rods 9 . For each surveying point 8, the respective reflector distance bi, b, b3, the respective angle of rotation ßi, ßz, ß3 around the horizontal axis 20 and the respective angle of rotation yi, yz, y3 around the vertical axis 19, in particular together with the height of the respective target window 10 above survey point 8. This information is transmitted to the processor 32 via the signal connection 21 .

Stored in the memory 34 for each of the survey points 8 are coordinates which correspond to the position of the respective survey point 8 in the global coordinate system 30 . The measuring position, in particular the origin 28 and the orientation of the measuring coordinate system 29, in the global coordinate system 30 is determined by means of common vector calculation using the processor 32 and stored in the memory element 34 from the coordinates of the measurement points 8 and the recorded measurement position values. The origin 26 of the camera coordinate system 27 is offset by a measurement camera vector t to the origin 28 of the measurement coordinate system 29 . The measuring camera vector t is unchangeable with regard to its length and its vertical portion due to the chosen attachment of the stereo camera 11 . The horizontal component of the measurement camera vector t depends on the orientation of the stereo camera 11 about the vertical axis 20. The measurement camera vector t is determined based on its known length, the likewise known vertical component and the horizontal component determined by means of the rotary encoder 20b of the vertical joint 19 definitely. The origin 26 and the orientation of the camera coordinate system 27 in the global coordinate system 30 are determined on the basis of the measuring camera vector t and the measuring position, in particular the origin 28 and the orientation of the measuring coordinate system 29 . Thus, relative positions of the measurement points 37, 38, 39, 40, 41 recorded by the stereo camera 11 can be determined in the global coordinate system 30 via common coordinate transformations executed in the evaluation unit 14, in particular by the processor 32.

During the recording of the pair of images by means of the stereo camera 11, this is preferably fixed relative to the measuring coordinate system 29, in particular to the stand 13. As a result, the pair of images can be recorded particularly precisely and robustly.

Alternatively, the stereo camera 11 can be moved, in particular pivoted, in particular pivoted about the vertical axis 20, relative to the measuring coordinate system 29 during the detection of the infrastructure component 1, in particular continuously and/or corresponding to the displacement movement of the infrastructure component 1. According to a further alternative embodiment, the stereo camera 11 is rigidly connected to the measuring coordinate system 29, in particular to the stand 13. A vertical joint 19 is not provided. The stereo camera 11 cannot be pivoted relative to the measurement coordinate system 29 .

The arrangement of the infrastructure component 1 is determined by its position and orientation. The component position is determined by the origin 42 of a component coordinate system 43 . The orientation of the component is determined by the orientation of the component coordinate system 43 .

The position of the measuring points 37, 38, 39, 40, 41 on the infrastructure component 1 is known; in particular, this is stored in a corresponding data record in the memory element 34. From this, the arrangement of the component coordinate system 43 with the origin 42 relative to the measuring points 37, 38, 39, 40, 41 is calculated, in particular by means of the processor 32. The arrangement of the components, in particular the component position and the component orientation, can be determined in the global coordinate system 30 using common coordinate transformation methods. The component position is determined in the global coordinate system 30 using the component position vector p pointing from the origin 31 to the origin 42 . The component orientation can be specified in the global coordinate system 30, for example using a corresponding component orientation s vector for the component coordinate system 43.

The infrastructure component 1 is moved from a storage component arrangement to a target component arrangement by means of the crane 35 . The component arrangement is changed during the relocation of the infrastructure component 1 continuously determined by means of the measuring system 2. In particular, the component arrangement is determined with a frequency in a range from 10 Hz to 100 Hz, in particular with a frequency of 55 Hz.

The desired component arrangement is stored in the storage element 34 for each of the infrastructure components 1 . The desired component arrangement of the respective infrastructure component 1 is preferably stored in the storage element 34 together with individual identification information or a sequential number. Using the individual identification information or the sequential number, the user can use the user interface 33 to select the target component arrangement that is appropriate for the infrastructure component 1 that is currently to be arranged.

The target component arrangement includes, for example, a target component position vector and a target component orientation vector. By means of the processor 32, the detected component arrangement is continuously compared with the target component arrangement, in particular with the frequency in the range from 10 Hz to 100 Hz, in particular with the frequency of 55 Hz. The comparison result is determined by the difference between the target component arrangement and the component arrangement. The result of the comparison is displayed to the user via the user interface 33 in the form of a difference position vector and a difference orientation vector.

The infrastructure component 1 is relocated using the result of the comparison. In particular, the infrastructure component 1 can be relocated to the target component arrangement in an automated manner, in particular in a controlled manner, by means of the crane 35 . If the result of the comparison, in particular the differential position vector and the differential orientation vector, falls below a predetermined arrangement threshold value, a permissible component arrangement is reached. The infrastructure component 1 is fixed in this arrangement. The method for arranging the infrastructure component 1 is ended. A further infrastructure component 1 can be transferred from the storage component arrangement to the desired component arrangement and fixed there in accordance with the method described above.

In addition or as an alternative to determining the arrangement of the infrastructure component 1, a deformation of the infrastructure component 1 can be determined by means of the measuring system 2. For this purpose, the marker vectors c are determined according to the method described above by capturing image pairs using the stereo camera. A transformation of the marker positions into the global coordinate system 30 is not required to determine the deformation of the infrastructure component 1 .

The position of the markings 24 is determined by the processor 32 using the marker vectors c in the component coordinate system 43 . Target marker positions of the marking elements 24 , in particular for each individual infrastructure component 1 , are stored in the storage element 34 . The corresponding target marking positions can be selected by the user via the user interface 33 using identification information that is unique to the infrastructure component 1 . The marker positions are compared with the target marker positions by means of the processor 32 . The comparison result is determined as the difference between the target marker position and the marker position. The result of the comparison correlates with a deformation of infrastructure component 1. The comparison result is determined, for example, during the relocation of the infrastructure component 1, in particular between the storage component arrangement and the target component arrangement, and/or in the target component arrangement, in particular before the fixing or after the fixing of the infrastructure component 1, and/or or for maintenance purposes after a certain maintenance period has expired.

The displacement of the infrastructure component 1 preferably takes place in such a way that a deformation threshold value is not exceeded. A reduction in the deformation can be achieved, for example, by more even displacement or additional suspension points.

The comparison result of the deformation is continuously stored in the storage element 34 . The documentation of the deformation enables improved quality assurance. The comparison result determined after the maintenance period can be a basis for the decision on maintenance measures. For this purpose, in particular, a comparison can be made between the target marker position and the marker position that was determined following the fixing of the infrastructure component 1 and/or the end of a maintenance period. The arrangement of components determined after a maintenance period can also be compared to the target arrangement of components and/or the arrangement of components following the fixing of the infrastructure component 1 in order to determine the result of the comparison.

The method described above enables infrastructure components 1 to be positioned particularly precisely and with repeat accuracy, in particular in a global coordinate system 30. The method makes Stresses, in particular overstresses, recognizable from infrastructure components 1 during transport and/or when fixing. Infrastructure components 1 can be maintained in a particularly efficient and reliable manner. Infrastructure components 1 can be monitored particularly flexibly, reliably, efficiently and economically with regard to their arrangement and stress by means of the method described above during installation and during their service life.

Two further examples of the use of the measuring system 2 described above or application examples of the method described above are explained with reference to FIGS. 4 and 5 . In contrast to the exemplary embodiment described above, the infrastructure component 1 shown in FIG. 4 is a building element, in particular a precast concrete wall. According to the method described above, the infrastructure component 1 is moved precisely into the target component arrangement by means of the measuring system 2 . The infrastructure component 1 is relocated manually using the comparison result determined by the measuring system 2 .

The exemplary embodiment shown in FIG. 5 differs from the exemplary embodiments described above in that the infrastructure components 1 detected by the measuring system 2 are a bridge girder and a bridge pier. The infrastructure component 1 embodied as a bridge girder is relocated to the target component arrangement by means of a crane 35 in accordance with the method described above, with the relocation taking place automatically using a comparison result between the component arrangement and the target component arrangement determined in accordance with the method described above. When relocating and/or in the target component arrangement, the deformation of the infrastructure part 1 determined and monitored in accordance with the procedure described above. Furthermore, the marker positions of the infrastructure components 1 designed as bridge girders and bridge piers are recorded, in particular after the completion of the bridge and/or after specified maintenance periods, in order to determine new deformations. For example, cracks in the infrastructure component 1 can be identified on the basis of the deformation image. Based on the determined deformations, in particular based on a deformation and/or crack progress determined therefrom, a decision can be made about maintenance measures that may be necessary.

A further method for measuring an infrastructure component 1 or a further application example for using the measuring system 2 is described with reference to FIG. 6 . In contrast to the exemplary embodiments described above, the markings 24 are attached to a measuring carriage 44 which is designed as a rail vehicle. The markings 24 and the measuring points 37, 38 marked therewith are coupled to the rails 4, which represent the infrastructure components 1 to be measured, via the measuring carriage 44.

To measure the infrastructure components 1 , in particular the rails 4 , the markings 24 are moved over the rails 4 in the measuring field 36 of the measuring system 2 by means of the measuring carriage 44 . The measuring system 2 continuously records the relative positions of the measuring points 37, 38 coupled to the infrastructure components 1, in particular with a measuring frequency of 10 Hz. The driving speed of the measuring car 44 is preferably in a range of 2 m/s to 20 m/s. Movement trajectories 44a of the measuring points 37, 38 are determined on the basis of the course of the relative positions over time. The arrangement of the markings 24 relative to the rails 4, in particular in a plane perpendicular to the direction of travel 45, is known, in particular fixed or variable by the measuring carriage 44 and is recorded on the measuring carriage 44. The position of the rails 4 at successive points in time and thus at different points along the direction of travel 45 in the global coordinate system 30 is determined by means of the evaluation unit 14, in particular by means of the processor 32, based on the course of the relative positions over time. The component arrangement of the infrastructure components 1, in particular the course of the rails 4, can be determined in the global coordinate system 30 as a result.

The method otherwise corresponds to the method according to the exemplary embodiments described above. The method enables a particularly precise and efficient determination of the component arrangement in the global coordinate system 30, in particular during track construction, after the rails 4 have been laid and/or for maintenance purposes after a specific maintenance period has expired.

Claims

- 34 - Claims

1. A method for measuring an infrastructure component (1), in particular a structural track component, comprising the steps:

Providing a mobile measuring system (2) with a stereo camera (11),

Arranging the measuring system (2) on the infrastructure component (1), capturing at least one pair of images of the infrastructure component (1) using the stereo camera (11),

Determining a relative position of at least one measuring point (37, 38, 39, 40, 41) coupled to the infrastructure component (1) using the at least one pair of images, and

Determining a deformation of the infrastructure component (1) based on the at least one relative position and/or detecting a measurement position of the measurement system (2) in a global coordinate system (30).

2. The method according to claim 1, characterized by determining a component arrangement of the infrastructure component (1) in the global coordinate system (30) based on the at least one relative position and the measurement position.

3. The method according to claim 2, characterized by comparing the component arrangement with a target component arrangement to determine a comparison result.

4. The method according to claim 3, characterized by relocating the infrastructure component (1) based on the comparison result. - 35 -

5. The method as claimed in one of the preceding claims, characterized in that the image pairs are recorded at a plurality of consecutive points in time.

6. The method according to claim 5, characterized by determining a movement path of the at least one measuring point (37, 38, 39, 40, 41) based on the plurality of image pairs.

7. The method as claimed in claim 5 or 6, characterized in that the image pairs are recorded at a frequency of at least 0.1 Hz.

8. The method according to any one of the preceding claims, characterized in that determining the measurement position of the measurement system (2) in the global coordinate system (30) includes the detection of survey points (8) and / or a satellite navigation signal.

9. The method according to any one of the preceding claims, characterized by determining a camera arrangement of the stereo camera (11) relative to the measurement position of the measurement system (2) when capturing the at least one pair of images.

10. The method according to any one of the preceding claims, characterized in that the determination of the deformation of the infrastructure component (1) is carried out by comparing the at least one relative position with at least one reference value. experienced according to claim 10, characterized in that the reference value is determined using a geometric model and/or a structural model of the infrastructure component (1) and/or using at least one reference image pair of the infrastructure component (1). Method according to one of the preceding claims, characterized by monitoring the deformation of the infrastructure component (1) when the infrastructure component (1) is relocated. Method according to one of the preceding claims, characterized by relocating the infrastructure component (1) based on the deformation. Method according to one of the preceding claims, characterized by detecting the relative position of at least three measuring points (37, 38, 39, 40, 41) of the infrastructure component (1) using the at least one pair of images. Method according to one of the preceding claims, characterized by detecting the at least one measuring point (37, 38, 39, 40, 41) by detecting a marking (24) coupled to the infrastructure component (1). Mobile measuring system (2) for recording an infrastructure component (1), in particular a track structure component, having a stereo camera (11) for recording at least one pair of images of the infrastructure component (1), an evaluation unit (14) for determining the relative position of at least one connected to the infrastructure component (1 ) paired Measuring point (37, 38, 39, 40, 41) based on the at least one pair of images, and a position determination unit (12) for determining a

Measuring position of the measuring system (2) in a global coordinate system (30). Mobile measuring system (2) according to Claim 16, characterized by measuring means (20a, 20b) for detecting a camera arrangement of the stereo camera (11) relative to the measuring position of the measuring system (2).