DE102015214857A1 - Method and system for creating a three-dimensional model of a production environment - Google Patents

Abstract

The invention describes a method for creating a three-dimensional model of an environment (1), in particular a production environment, with a number of objects (2, 3, 4), in particular production resources. The method according to the invention comprises, in a step a), the arrangement of at least three markers (7, 8, 9, 10) in the environment (1) to be measured, each of the markers (7, 8, 9, 10) being such in that it can be detected and clearly identified by different measuring locations by means of a laser scanner (5) which is designed to scan the surroundings (1). In a step b), at least one parameter (12, 13, 14, 15) is determined for each of the markers (7, 8, 9, 10), the at least one parameter (12, 13, 14, 15) being the respective Position of the marker (7, 8, 9, 10) relative to the at a measuring point (11) arranged laser scanner (5) characterized, wherein the determination of the at least one parameter (12, 13, 14, 15) by scanning the environment (1 ) with the laser scanner (5), which is arranged at the measuring location (11). In step c), the environment (1) is scanned with the laser scanner (5) from a first measuring location (11), wherein the sampling a first point cloud with a discrete set of three-dimensionally distributed sampling points of the environment (1) is determined. Furthermore, in a step d) the invention comprises the detection and detection of the position of the at least three markers (7, 8, 9, 10) in the first point cloud by processing the parameter determined for each marker (7, 8, 9, 10) ( 12, 13, 14, 15). In step e), steps b), c) and d) are repeated for at least one second measuring location (11), whereby at least one second point cloud and the position of the at least three markers (7, 8, 9, 10) in the second Point cloud is won. Finally, in a step f), a surface geometry from the first and the at least one second point cloud is determined by combining the sampling points of the first and the at least one second point cloud such that the at least three markers (7, 8, 9, 10) of all Point clouds lie in each other when superimposed.

Description

The invention relates to a method for creating a three-dimensional model of an environment, in particular a production environment, with a number of objects, in particular production resources. The invention further relates to a laser scanner, a marker and a system for creating a three-dimensional model comprising a laser scanner according to the invention and a plurality of markers according to the invention.

Laser scanning or laser scanning refers to the line or raster-like sweeping of surfaces or bodies with a laser beam in order to measure, process or create an image. Sensors that deflect the laser beam accordingly are called laser scanners. A laser scanner consists of a scanning or scanning head and a driver and control electronics. In laser scanning, the surface geometry of objects, e.g. by means of pulse transit time, phase difference in comparison to a reference or by triangulation of laser beams, recorded digitally. This results in a discrete set of sampling points, which is referred to as a point cloud. The coordinates of the measured points are determined from the angles and the distance with respect to an origin, e.g. the location of the laser scanner. As a result, three-dimensional laser scanning yields a three-dimensional point cloud and thus a complete image of a measurement scene. On the basis of the point cloud, for example, individual dimensions, such as Lengths and angles, determined or it is constructed from a closed surface and used for visualization. This makes it possible, for example, to create a complete three-dimensional model of the production environment with a number of production resources arranged therein in the vicinity of production plants. Production resources can be, for example, robots, machines, tools, walls, columns, carriers or other objects.

A problem of creating a three-dimensional model is that it is necessary to place the laser scanner in such a way that as far as possible all shadowing can be compensated. If this is not possible, several measurements must be taken from different measuring locations and the respective point clouds combined.

A method for detection or position detection of known objects is for example from the EP 0 364 614 A1 known. As a criterion for the recognition of the position and orientation of the known body with respect to a reference position, the calculation of the moments of inertia of the line of intersection between a body surface of a measurement object, which is the known body, and a virtual volume primitive, and a subsequent main axis transformation is used. However, this method, too, can not address the problem of shadowing in a scan and requires multiple measurements of different measurement locations and their combination.

The US 2011/052263 A1 discloses a scanner that allows the creation of a three-dimensional image of an environment.

It is an object of the present invention to provide a method that enables the creation of a three-dimensional model of an environment, in particular a production environment with a number of production resources, in a simpler and faster manner with high precision.

Another object of the invention is to provide a laser scanner and other tools that enable the efficient implementation of the method.

It is finally an object of the invention to provide a system for creating a three-dimensional model of an environment, which allows the rapid implementation of the method with high efficiency and little effort.

These objects are achieved by a method according to the features of claim 1, a computer program product according to the features of claim 14, a marker according to the features of claim 15, a laser scanner according to the features of claim 18 and a system according to the features of claim 22. Advantageous embodiments emerge from the dependent claims.

• a) Anordnung von zumindest drei Markern in der zu vermessenden Umgebung, wobei jeder der Marker derart beschaffen ist, dass er durch einen Laserscanner, der zur Abtastung der Umgebung ausgebildet ist, von unterschiedlichen Messorten erfassbar, insbesondere eindeutig, identifizierbar, ist. Die Marker können derart in der Umgebung angeordnet sein, dass diese nach einer Abtastung rückstandslos von ihrem Anbringungsort entfernbar bzw. von diesem demontierbar sind. Die Anbringungsorte der Marker können derart beschaffen sein, dass diese auch für spätere Messungen wieder verwendet werden können.
• b) Ermittlung zumindest eines Parameters für jeden der Marker, wobei der zumindest eine Parameter die jeweilige Lage des Markers relativ zu dem an einem Messort angeordneten Laserscanner charakterisiert, wobei die Ermittlung des zumindest einen Parameters durch Abtastung der Umgebung mit dem Laserscanner erfolgt, der an dem Messort angeordnet ist. Durch diesen Schritt wird somit die Position jedes der Marker relativ zu einem bestimmten Messort durch Abtastung mit dem Laserscanner ermittelt.
• c) Abtastung der Umgebung mit dem Laserscanner von einem ersten Messort aus, wobei bei der Abtastung eine erste Punktwolke mit einer diskreten Menge von dreidimensional verteilten Abtastpunkten der Umgebung ermittelt wird. Die Abtastung der Umgebung mit dem Laserscanner von dem ersten Messort aus erfolgt zeitlich nachdem für jeden der Marker der in Schritt b) erwähnte, zumindest eine Parameter ermittelt wurde.
• d) Erkennung und Detektion der Lage der zumindest drei Marker in der ersten Punktwolke durch Verarbeitung des für jeden Marker ermittelten Parameters. Die Erkennung und Detektion der Lage der zumindest drei Parameter erfolgt unter Zuhilfenahme der in Schritt b) vorab ermittelten Parameter, welche die jeweilige Lage eines Markers relativ zu dem Messort charakterisieren.
• e) Wiederholung der Schritte b), c) und d) für zumindest einen zweiten Messort, wodurch eine zweite Punktwolke und die Lage der zumindest drei Marker in der zweiten Punktwolke gewonnen wird. Der zweite Messort ist ein von dem ersten Messort unterschiedlicher Messort. Von dem zweiten Messort wird die Umgebung aus einer anderen Perspektive abgetastet.
• f) Ermittlung einer Oberflächengeometrie aus der ersten und der zumindest einen zweiten Punktwolke, indem die Abtastpunkte der ersten und der zumindest einen zweiten Punktwolke derart kombiniert werden, dass die zumindest drei Marker aller Punktwolken bei der Überlagerung ineinander liegen. Dadurch ist durch mehrfache Abtastung die Ermittlung einer vollständigen Oberflächengeometrie der Umgebung möglich.

The object is achieved by a method for creating a three-dimensional model of an environment with a number of objects. In particular, the environment is a production environment with production resources. Such production resources can be, for example, robots, machines, tools. Other objects include walls, pillars, beams, or other objects in the area. The method comprises the steps:

• a) arrangement of at least three markers in the environment to be measured, each of the markers being such that it can be detected, in particular unambiguously, identifiable by a laser scanner, which is designed to scan the environment, from different measurement locations. The markers can be arranged in the environment such that they are without residue after scanning from their mounting location removable or can be removed from this. The locations of the markers can be such that they can also be used again for later measurements.
• b) determining at least one parameter for each of the markers, wherein the at least one parameter characterizes the respective position of the marker relative to the laser scanner arranged at a measuring location, wherein the determination of the at least one parameter takes place by scanning the surroundings with the laser scanner which is connected to the laser scanner Measuring location is arranged. This step thus determines the position of each of the markers relative to a particular measurement location by scanning with the laser scanner.
• c) scanning the environment with the laser scanner from a first measurement location, wherein the scan is a first point cloud with a discrete amount of three-dimensionally distributed sampling points of the environment is determined. The scanning of the environment with the laser scanner from the first measuring location takes place in time after at least one parameter has been determined for each of the markers mentioned in step b).
• d) Detecting and detecting the position of the at least three markers in the first point cloud by processing the parameter determined for each marker. The detection and detection of the position of the at least three parameters takes place with the aid of the parameters determined in advance in step b), which characterize the respective position of a marker relative to the measuring location.
• e) repeating steps b), c) and d) for at least one second measuring location, whereby a second point cloud and the position of the at least three markers in the second point cloud is obtained. The second location is a different location from the first location. From the second location, the environment is scanned from a different perspective.
• f) Determining a surface geometry from the first and the at least one second point cloud, by combining the sampling points of the first and the at least one second point cloud in such a way that the at least three markers of all point clouds lie in one another during the superposition. As a result, multiple sampling makes it possible to determine a complete surface geometry of the environment.

In the method according to the invention, a method known per se is used by scanning an environment to be measured from different perspectives with the aid of a laser scanner. In order to be able to combine the measured values acquired in the various scans in the form of sampling points in three-dimensional space, a number of markers are arranged in the environment to be measured. In conventional methods, the markers will be recognized by a computing unit following a scan. After recognition, the determination of a geometric relation of the markers takes place relative to one another. For example, the centers of the markers formed as balls and their distance from one another can be determined for this purpose. This procedure must be repeated for each scan. By "overlaying" the geometry of the markers in three-dimensional space and checking whether they fit together, the overall model can then be determined. However, this approach is time consuming and computationally intensive because the markers are determined by processing the three-dimensionally distributed sampling points from the point clouds, i. to be recognized. This often leads to errors, for example, if the markers similar objects or objects are incorrectly identified as a marker. This often requires manual post-processing.

In contrast, the present method provides for determining the position of the markers in the environment to be measured in advance by means of the laser scanner. Likewise, for example, a geometric relation of the markers to each other can already take place before the actual scanning of the surroundings. Thus it is already known during the subsequent scan (s) where the markers are contained in the point clouds. As a result, the post-processing of the samples faster, as well as a costly preprocessing can be omitted to detect markers in the individual scans. In particular, errors with regard to the identification of markers can be avoided. As a result, it is also possible to determine in real time or during a scanning process at which measuring location the laser scanner is located, which also simplifies the further processing of the sampled values.

The parameter which describes the respective position of the markers relative to the laser scanner arranged at one of the measuring locations expediently comprises a direction information. The direction refers to a previously defined coordinate system, which is expediently Cartesian. The origin of the coordinate system can basically be chosen arbitrarily. So it is possible that the origin of the coordinate system lies in the environment to be measured. However, the origin of the coordinate system may also be chosen outside the environment to be measured, and e.g. are at a prominent point, such as a building, a church tower, etc.

Expediently, the parameter which describes the respective position of the markers relative to the laser scanner arranged at one of the measuring locations comprises a distance between the laser scanner and the respective marker as well as at least one Angle information. The distance refers, for example, to a known origin of the laser scanner and a center of the marker. The angle information in turn refers to the previously selected coordinate system.

The number of markers can basically be chosen arbitrarily, as long as each scan contains at least three markers in the acquired data. It should be noted that the point clouds resulting from scans, which are to be combined with each other, comprise the same three markers. Otherwise, a combination and referencing of the point clouds or scans to each other is not possible.

It is also expedient if the position and / or position of the markers is not changed between the scanning of the surroundings with the laser scanner from one of the measuring locations and a temporally subsequent scanning of the surroundings from another of the measuring locations. Only in this way can it be ensured that in the case of point clouds to be combined with one another, the three markers can be interlaced.

It can furthermore be provided that the laser scanner processes only the parameters associated with those markers for detecting the surface geometry of the environment in which no change in position was detected between two scans. This ensures that the at least three markers of the point clouds can be superposed in the overlay, whereby the correct surface geometry of the environment to be measured can be determined.

According to a further embodiment, each of the markers comprises a communication device, wherein for determining the at least one parameter, a respective marker emits a signal or a message on the basis of which the laser scanner can determine a respective position information of the relevant marker. For example, a marker can emit a sound signal for this purpose. The laser scanner determines from the sound signal the direction and possibly also the (approximate) distance to the marker emitting the sound signal. After the approximate direction has been determined, the laser scanner then scans the exact location information, i. the above-mentioned at least one parameter.

Each marker is such that it can be uniquely identified by the laser scanner based on its shape and / or size and / or surface condition and / or color. The unique identification makes it easier to identify the markers in the scanned point cloud and to identify it for further processing. In particular, this makes it possible to determine the geometric arrangement of the markers used for superimposition in a simple and precise manner. Furthermore, the determination of the position of each marker can thereby be done in a relatively short time.

In this context, it is expedient for the laser scanner to assign an identification to each of the detected markers. For example, an identification may be a unique, e.g. be consecutive, number and the like. Alternatively, the laser scanner may receive an identification date from each of the markers. The identification date can be transmitted from the communication device to the laser scanner for this purpose. If this signal is e.g. transmitted continuously or periodically, this can also be used to determine the position information.

It is furthermore expedient if each of the markers comprises a device for motion detection, with which a respective marker can detect a movement, wherein a respective marker, when it detects a movement, transmits a message indicating the movement to the laser scanner. A movement may include a conscious or unconscious change of the location of the marker in any spatial direction. A movement can also be a shock of the marker. In addition, in the message in which the movement of the marker is transmitted to the laser scanner, the information identifying the marker, e.g. the identification date to be transmitted.

Conveniently, upon receiving the message indicating the movement, the laser scanner considers the message emitting markers in determining the surface geometry in a predetermined manner. For example, this marker will not be considered by the laser scanner for further processing since no reference to a previously acquired sample can be made. Alternatively, the marker may also emit a new identification date, the identification date being associated with the now changed position, which may eventually be considered and processed in future scans.

According to a further expedient embodiment, the laser scanner can determine its position relative to the at least three markers for each measuring location, the position being processed in the determination of the surface geometry of the surroundings.

The invention further provides a computer program product directly into the internal memory a digital arithmetic unit can be loaded and includes software code sections, with which the steps of the previously described methods are performed when the product is running on a computing unit. The computer program product can be in the form of a physical data carrier, such as a DVD, a CD, a USB memory, a memory card, but also in the form of a transferable via a communication channel file.

The object is further achieved by a marker for creating a three-dimensional model of an environment, in particular a production environment, which is such that it is clearly identifiable by its shape and / or size and / or surface texture and / or color by a laser scanner, and a communication device for emitting a signal or a message, on the basis of which or the laser scanner can determine a respective position information of the marker, and a device for detecting intrinsic movements.

The marker may further comprise an energy store for supplying the communication device and the movement detection device. Alternatively or additionally, the marker may comprise a device for generating energy for supplying the communication device and the device for detecting movement.

The object is further achieved by a laser scanner for scanning an environment, in particular a production environment, with a number of objects, in particular production resources, with a control and computing unit, which for detecting the position of a respective inventive marker according to step b) of the above Method is formed.

The laser scanner can furthermore be designed to receive and process a signal or a message by means of which the laser scanner can determine a respective position of the marker.

The laser scanner can also be designed to receive and process a signal or message, by means of which the laser scanner can determine a respective identification date of the marker.

In addition, the control and computing unit of the laser scanner can be designed to detect and identify a respective marker in a point cloud generated by scanning.

The arithmetic unit may be part of the laser scanner or a separate arithmetic unit, which communicates with the laser scanner for the exchange of data. The task of the arithmetic unit is in particular to carry out the preprocessing of the position determination of the markers arranged in the environment to be measured and to calculate the surface geometry of the surroundings.

The object is further achieved by a system for creating a three-dimensional model of an environment, in particular a production environment, with a number of objects, in particular production resources, wherein the system comprises at least three markers of the type described here and a laser scanner of the type described here.

The invention will be explained in more detail below with reference to exemplary embodiments in the drawing. Show it:

1 a schematic representation of a system according to the invention for creating a three-dimensional model of a production environment in a plan view;

2 a schematic representation of the determination of the position of a number of markers relative to a first measurement location at which a scan of the environment is to be made with a laser scanner;

3 a schematic representation of the determination of the position of a number of markers relative to a second measuring location at which a scan of the environment with the laser scanner is to take place;

4 a schematic representation of the determination of the position of a number of markers relative to a third measuring location at which a scan of the environment with the laser scanner is to take place;

5 a schematic representation of a laser scanner according to the invention;

6 a schematic representation of a marker according to the invention; and

7 a flowchart illustrating the flow of the inventive method.

1 shows a schematic representation of a system according to the invention for creating a three-dimensional model of a production environment 1 which represents an environment to be measured. The production environment 1 includes a number of objects in the form of production resources 2 . 3 . 4 , The production resources 2 . 4 are, for example, processing machines or tools. In addition, objects can be pillars, carriers or other structural objects. The production machine 2 represents an articulated robot 3 with, for example, three rotating arms 3A . 3B . 3C dar. A working area of the articulated robot 3 is with the reference numeral 3D characterized, wherein the work area 3D in one area of the production environment 1 between the production resource 2 and the production resource 4 is arranged. For example only, the production resource includes a first subcomponent 4A and a second subcomponent 4B which are arranged at a right angle to each other. The production resource 3 performs only as an example in the context of a processing process, a movement between the two production resources 2 and 4 in which, for example, a material part of the production resource 4 to the production resource 2 moved, at the production resource 2 edited and then back to the production resource 4 to be led.

To create a three-dimensional model of the production environment 1 Creating a surface geometry of the production environment 1 required. In particular, in the context of the method is a respective surface geometry of the production resources 2 . 3 . 4 to create. This is done by means of a laser scanner 5 which is in the production environment 1 in the present embodiment, only by way of example in the plan view of the schematic representation at a first measuring location 11-1 is arranged at the top left. The production resource 5 sends in a known manner a scanning signal 5S through a line or raster-like sweeping of the surfaces of the production resources 2 . 3 . 4 and other body (eg, columns, stretcher, etc.) in the production environment 1 done to measure these. At the in 1 shown relative arrangement of the laser scanner 5 and production resources 2 . 3 . 4 the problem arises of shadowing 6 , ie surface areas, which by the scanning signal 5S can not be detected due to their geometric orientation.

To the surface geometry of the production resources 2 . 3 . 4 the production environment 1 To be able to fully detect, a plurality of measurements at different locations 11 performed, with each measurement takes place at or from a different location. In this embodiment, these are the second measurement location 11-2 and the third location 11-3 , The different measurements are then combined together and assembled into a complete surface geometry.

A combination of different measurements from different locations 11 The individual measurements (also referred to as sampling) must be referenced to one another. This is done with the help of so-called markers. In the embodiment of 1 are merely exemplary four markers 7 . 8th . 9 . 10 shown. The markers 7 . 8th . 9 . 10 may be such that they are based on their shape and / or size and / or surface texture and / or color by the laser scanner 5 are clearly identifiable. In the embodiment shown here, the markers 7 . 8th . 9 . 10 in cross-section different shapes. This is the marker 7 merely as an octagon, the marker 8th as a pentagon, the marker 9 as a dodecagon and the marker 10 designed as a ball. The markers 7 . 8th . 9 . 10 are in different positions in the production environment 1 arranged. These are not just in the in 1 arranged distributed overhead view, but can also be arranged at different height positions (ie perpendicular to the plane).

The markers are relative to the measurement sites 11-1 . 11-2 . 11-3 arranged such that at the respective measuring location 11-1 . 11-2 . 11-3 arranged laser scanner 5 at least three of the markers 7 . 8th . 9 . 10 can capture. In particular, for a combination of two scans, it is necessary for the same three markers in the scans or measurements 7 . 8th . 9 . 10 as a further constraint must be ensured that the markers 7 . 8th . 9 . 10 were not changed in position between the two scans.

In the embodiment described here, the laser scanner 5 from the first measuring position 11-1 for carrying out a first measurement to the second measuring location 11-2 to carry out a second measurement and finally to the third location 11-3 to carry out a third measurement. The current location of the laser scanner 5 is by a solid line of the laser scanner 5 marked while a broken line of the laser scanner 5 only represents a specific location or location. The center of the site is by the point to which the line of the reference 11 protrudes, marked.

The method according to the invention, as described, sees as the first step S71 of FIG 7 illustrated flowchart arranging at least three markers in the environment to be measured before. Each of the markers 7 . 8th . 9 . 10 is, as described, from the laser scanner 5 uniquely identifiable as a marker. This can, as in connection with 1 described, be ensured by its external nature. Alternatively, the markers can also be formed identically, preferably as spheres, if they can be assigned a unique identification date by the laser scanner, eg by the markers 7 . 8th . 9 . 10 a unique identifying date to the Transfer laser scanner. For this purpose, a respective marker 7 . 8th . 9 . 10 a communication device 61 include (cf. 6 ). The communication device 61 is for example by a, in the respective marker 7 . 8th . 9 . 10 provided energy storage 63 energized. The energy storage may be, for example, a battery or an accumulator. Alternatively or additionally, a respective marker 7 . 8th . 9 . 10 an energy recovery facility 64 to extract energy from the environment. The power supply can be designed such that it can be switched on or off via a mechanical switching element. The power supply can also be turned off or on in other ways, eg by vibration or a characteristic pattern of vibration.

In addition, has a respective marker 7 . 8th . 9 . 10 preferably via a device 62 for motion detection of the marker in question 7 . 8th . 9 . 10 , The device 62 for motion detection and the communication device 61 be through a computing unit 60 controlled. The arithmetic unit 60 is also from the energy store 63 and / or the energy recovery device 64 energized.

To such, by a respective marker 7 . 8th . 9 . 10 The laser scanner has the identification date sent out 5 also via a communication device 52 , The communication device 52 is with a control and processing unit 50 of the laser scanner 5 coupled. In addition, the laser scanner has 5 via the initially mentioned scanning device 51 , Such a laser scanner 5 is exemplary in 5 shown.

In a second step S72, the determination of the position of each marker takes place 7 . 8th . 9 . 10 relative to the first location 11-1 , The procedure is explained with reference to 2 explained. To determine the position of each marker is by scanning the environment with the laser scanner 5 every marker 7 . 8th . 9 . 10 localized. This is for each marker 7 . 8th . 9 . 10 at least one position parameter obtained, which is the respective position of the marker 7 . 8th . 9 . 10 relative to that at a measuring location, here: first measuring location 11-1 , arranged laser scanner 5 characterized. The reference number 12-1 indicates a positional parameter for the marker 7 in relation to the measuring location 11-1 , The same applies to the position parameters 13-1 . 14-1 and 15-1 that focus on the markers 8th . 9 . 10 in relation to the measuring location 11-1 Respectively. In this example it is assumed that the marker 8th due to the presence of the production resource 3 through the laser scanner 5 can not be detected, which is why the relevant line is shown differently.

The position parameters 12-1 . 14-1 and 15-1 for through the laser scanner 5 detectable marker 7 . 9 and 10 include a respective distance between the centers of the laser scanner 5 and the respective marker 7 . 9 . 10 and an angle indication with respect to a coordinate system 30 , The coordinate system 30 is, for example, a Cartesian coordinate system whose x-axis extends only by way of example to the right in the drawing direction, the y-axis of which extends upwards in the drawing direction and whose z-axis extends vertically out of the sheet direction. The coordinate system 30 can be chosen differently. In particular, the origin of the coordinate system need not be in the area of the environment to be measured.

Determining the position of each marker 7 . 9 . 10 can be done by a conventional scan of the environment to be measured. If the laser scanner 5 the markers 7 . 9 . 10 can not detect, for example, iteratively increases its resolution until the markers 7 . 9 . 10 be recognized.

Alternatively, the markers can transmit direction information to the laser scanner by emitting a corresponding signal, so that the determination of the position of the relevant marker 7 . 8th . 9 . 10 in a simpler way is feasible. For this purpose, for example, a respective marker 7 . 8th . 9 . 10 emit a sound signal, whereupon the laser scanner 5 focused in the direction of the source of the sound signal and from the intensity of the sound signal can close to the distance. An accurate distance determination then takes place by conventional sampling.

In a third step S73, the sampling of the production environment to be measured then takes place 1 with the help of the laser scanner 5 from the first location 11-1 out. The scan yields a first point cloud with a discrete set of three-dimensionally distributed sample points of the environment. In a further step S74 then the detection and detection of the position of the marker takes place 7 . 9 . 10 in the first point cloud. The detection and detection uses the position parameters obtained in advance in step S72. In addition, the laser scanner knows each detected marker 7 . 9 . 10 due to the duration of the light its own current location. This information can also be used to determine the surface geometry.

After completion of the scan, the laser scanner is moved to the second location 11-2 moved (see 3 ). The laser scanner determines at this measuring location 5 again the position of each marker in the manner previously described. In this embodiment, it is assumed that the laser scanner 5 all four markers 7 . 8th . 9 . 10 detect can. As described, for each marker 7 . 8th . 9 . 10 the positional parameters 12-2 . 13-2 . 14-2 . 15-2 , ie the distance and a direction information determined. This corresponds to the step S75 in FIG 7 , Subsequently, in step S76, the scanning of the environment with the laser scanner 5 from the second location 11-2 out. A second point cloud is determined with a discrete set of three-dimensionally distributed sampling points of the production environment 1 , Subsequently, in step S77, recognition and detection of the position of the markers 7 . 8th . 9 . 10 in the second point cloud, this being done using the previously determined positional parameters.

This procedure becomes an example for the third location 11-3 repeatedly (cf. 4 ). Again, in the manner described, a determination of the position parameters 12-3 . 13-3 . 14-3 . 15-3 each marker 7 . 8th . 9 . 10 relative to the third location 11-3 performed. It is assumed that all markers 7 . 8th . 9 . 10 through the laser scanner 5 are detectable. Then the production environment is scanned 1 with the laser scanner 5 from the third location 11-3 out. As a result, a third point cloud is detected with a discrete set of three-dimensionally distributed sampling points of the environment. Subsequently, the detection and detection of the position of the markers in the second point cloud takes place with the aid of the previously determined position parameters. This procedure thus corresponds to the repetition of step S75 to S77.

If the number of scans is sufficient (step S78), the determination of a surface geometry is performed in step S79. The determination of the surface geometry is carried out from the first, the second and the third point cloud by the sampling points of the first, the second and the third point cloud are combined in such a way that the coincident recognized markers (here: 7 . 9 . 10 since only these are contained in all three scans) of the three point clouds are superimposed in the overlay. This procedure is known per se from the prior art and is therefore not explained in detail.

The method thus uses a detection and identification of markers that takes place before the actual measurement procedure is carried out. The laser scanner can be used for every measuring location 5 Also determine its position relative to the starting point of the corresponding previous scan, which facilitates or accelerates the combination of the point clouds together.

Since the method is only to be performed when it is ensured that the markers have not moved between the three scans, a detection of a movement is carried out with the aid of the devices already mentioned 62 for motion detection of a respective marker 7 . 8th . 9 . 10 , Such a device can, for example, by in the respective marker 7 . 8th . 9 . 10 be implemented integrated acceleration sensors. Is there a marker? 7 . 8th . 9 . 10 At a position where a measured physical quantity indicates a quiet position, for example because a steady state is reached, the marker may 7 . 8th . 9 . 10 optional this idle state to the laser scanner 5 transfer. As soon as a marker detects a change in position, it transmits information about the change in position (optionally with information about the extent of the change in position) together with its identification date to the laser scanner 5 ,

The laser scanner 5 can use this information to judge if changing the position of a particular marker 7 . 8th . 9 . 10 is relevant. In addition, the laser scanner can store the identification date of the moving marker and the time of a position change to process this information later in determining the surface geometry. Optionally, a corresponding scan may be discarded during processing.

By receiving information about when the position of a marker is changing, the laser scanner can judge in real time whether there are enough markers at the constant positions described above. The laser scanner exclusively uses those markers which have a constant position in the above sense, as an orientation aid for the combination of the point clouds of different scans. Has the laser scanner 5 If a sufficient number of markers are detected for a scan to be performed, the samples are oriented in real time to one another and, if necessary, combined. In addition, this procedure allows the laser scanner to determine in real time or during a scanning process, where the laser scanner is located. For this purpose, it is necessary that at least three markers for the laser scanner can be detected, which are not moved or were in a previous scan.

The combination of multiple point clouds requires that in each point cloud at least three markers are recognizable whose identification data differ and whose position is constant to previous point clouds or scans. "Constant" means that the laser scanner 5 recognizes the unique marker in multiple scans or point clouds, wherein the position of the marker has not changed.

However, it is not necessary for every point cloud to contain all the markers distributed in the environment are recognizable. In addition, it is not necessary that all markers remain permanently at the once provided position. Markers that have already been detected can be changed in position.

In particular, it may be expedient to place markers, which are no longer in its field of view in view of a specific measuring location of the laser scanner, at a different position, so that with a small number of different markers a large environment to be measured, in which individual scans or point clouds referenced to each other, to be able to cover.

LIST OF REFERENCE NUMBERS

1

Environment (production environment)

2

Object (production resource)

3

Object (production resource)

3A

rotating arm

3B

rotating arm

3C

rotating arm

3D

Workspace

4

Object (production resource)

4A

first subcomponent

4B

second subcomponent

5

laser scanner

5S

sampling

6

non-detectable areas of production resources by the laser scanner

7

marker

8th

marker

9

marker

10

marker

11-1

first location

11-2

second measuring location

11-3

third measuring location

12-1

Position parameters for markers 7 in terms of location 11-1

13-1

Position parameters for markers 8th in terms of location 11-1

14-1

Position parameters for markers 9 in terms of location 11-1

15-1

Position parameters for markers 10 in terms of location 11-1

12-2

Position parameters for markers 7 in terms of location 11-2

13-2

Position parameters for markers 8th in terms of location 11-2

14-2

Position parameters for markers 9 in terms of location 11-2

15-2

Position parameters for markers 10 in terms of location 11-2

12-3

Position parameters for markers 7 in terms of location 11-3

13-3

Position parameters for markers 8th in terms of location 11-3

14-3

Position parameters for markers 9 in terms of location 11-3

15-3

Position parameters for markers 10 in terms of location 11-3

30

coordinate system

50

Computing unit of a laser scanner

51

scanning

52

communicator

60

Computing unit of a marker 7 . 8th . 9 . 10

61

Communication device of a marker 7 . 8th . 9 . 10

62

Device for detecting the movement of a marker 7 . 8th . 9 . 10

63

Energy storage of a marker 7 . 8th . 9 . 10

64

Energy recovery device of a marker 7 . 8th . 9 . 10

S71

step

S72

step

S73

step

S74

step

S75

step

S76

step

S77

step

S78

step

S79

step

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0364614 A1 [0004]
• US 2011/052263 A1 [0005]

Claims (22)

Method for creating a three-dimensional model of an environment ( 1 ) with a number of objects ( 2 . 3 . 4 ) comprising the steps of: a) arranging at least three markers ( 7 . 8th . 9 . 10 ) in the environment to be measured ( 1 ), each of the markers ( 7 . 8th . 9 . 10 ) such that it can be detected by a laser scanner ( 5 ), which is used to scan the environment ( 1 ) is formed, can be detected by different measuring locations; b) determination of at least one parameter ( 12 . 13 . 14 . 15 ) for each of the markers ( 7 . 8th . 9 . 10 ), wherein the at least one parameter ( 12 . 13 . 14 . 15 ) the respective position of the marker ( 7 . 8th . 9 . 10 ) relative to that at a measuring location ( 11 ) arranged laser scanner ( 5 ), wherein the determination of the at least one parameter ( 12 . 13 . 14 . 15 ) by scanning the environment ( 1 ) with the laser scanner ( 5 ), which at the measuring location ( 11 ) is arranged; c) scanning the environment ( 1 ) with the laser scanner ( 5 ) from a first measuring location ( 11 ), wherein in the scan, a first point cloud having a discrete set of three-dimensionally distributed sample points of the environment ( 1 ) is determined; d) detection and detection of the position of the at least three markers ( 7 . 8th . 9 . 10 ) in the first point cloud by processing the for each marker ( 7 . 8th . 9 . 10 ) ( 12 . 13 . 14 . 15 ); e) repetition of steps b), c) and d) for at least one second measuring location ( 11 ), whereby at least a second point cloud and the position of the at least three markers ( 7 . 8th . 9 . 10 ) is obtained in the second point cloud; f) determining a surface geometry from the first and the at least one second point cloud by combining the sampling points of the first and the at least one second point cloud such that the at least three markers ( 7 . 8th . 9 . 10 ) of all point clouds in the superposition lie in each other. Method according to Claim 1, in which the parameter ( 12 . 13 . 14 . 15 ), which determines the position of the markers ( 7 . 8th . 9 . 10 ) relative to the laser scanner arranged at one of the measuring locations ( 5 ) comprises direction information. Method according to Claim 1 or 2, in which the parameter ( 12 . 13 . 14 . 15 ), which determines the position of the markers ( 7 . 8th . 9 . 10 ) relative to the laser scanner arranged at one of the measuring locations ( 5 ) describes a distance between the laser scanner ( 5 ) and the respective marker ( 7 . 8th . 9 . 10 ) and at least one angle information. Method according to one of the preceding claims, in which between the sampling of the environment ( 1 ) with the laser scanner ( 5 ) from one of the measuring locations ( 11 ) and a subsequent sampling of the environment ( 1 ) from another of the measuring locations the position and / or position of the markers ( 7 . 8th . 9 . 10 ) is not changed. Method according to one of the preceding claims, in which the laser scanner ( 5 ) for determining the surface geometry of the environment ( 1 ) only such parameters ( 12 . 13 . 14 . 15 ), such markers ( 7 . 8th . 9 . 10 ) are assigned, in which no change in position was detected between two scans. Method according to one of the preceding claims, in which each of the markers ( 7 . 8th . 9 . 10 ) a communication device ( 61 ), wherein for determining the at least one parameter ( 12 . 13 . 14 . 15 ) a respective marker ( 7 . 8th . 9 . 10 ) emits a signal or a message based on which or the laser scanner ( 5 ) a respective position information of the marker in question ( 7 . 8th . 9 . 10 ) can determine. Method according to one of the preceding claims, in which each marker ( 7 . 8th . 9 . 10 ) through the laser scanner ( 5 ) is clearly identified on the basis of its shape and / or size and / or surface texture and / or color. Method according to one of Claims 1 to 7, in which the laser scanner ( 5 ) each of the markers ( 7 . 8th . 9 . 10 ) assigns an identification. Method according to one of Claims 1 to 7, in which the laser scanner ( 5 ) of each of the markers ( 7 . 8th . 9 . 10 ) receives an identification date. Method according to one of the preceding claims, in which each of the markers ( 7 . 8th . 9 . 10 ) a device for motion detection ( 62 ), with which a respective marker ( 7 . 8th . 9 . 10 ) can detect a movement, wherein a respective marker ( 7 . 8th . 9 . 10 ), when it detects a movement, sends a message indicating the movement to the laser scanner ( 5 ) transmits. Method according to Claim 10, in which the laser scanner ( 5 ) upon receipt of the message indicating the movement, the marker emitting the message ( 7 . 8th . 9 . 10 ) are taken into account in the determination of the surface geometry in a predetermined manner. The method of claim 11, wherein the marker ( 7 . 8th . 9 . 10 ) sending out the message indicating the movement in which message additionally sends out a changed identification date. Method according to one of the preceding claims, in which the laser scanner ( 5 ) for each measuring location ( 11 ) its position relative to the at least three markers ( 7 . 8th . 9 . 10 ), the Position in determining the surface geometry of the environment ( 1 ) is processed.  A computer program product that can be loaded directly into the internal memory of a digital computing unit and includes software code portions that perform the steps of any of the preceding claims when the product is run on the computing unit. Marker for creating a three-dimensional model of an environment ( 1 ), which is designed such that, by virtue of its shape and / or size and / or surface condition and / or color, it can be detected by a laser scanner ( 5 ) is uniquely identifiable and that a communication device for transmitting a signal or a message by means of which the laser scanner ( 5 ) a respective position information of the marker ( 7 . 8th . 9 . 10 ) and a device for detecting intrinsic movements. Marker according to claim 15, comprising an energy store ( 63 ) for the supply of the communication device ( 61 ) and the motion detection device ( 62 ). Marker according to claim 15 or 16, comprising a device for generating energy ( 64 ) for the supply of the communication device ( 61 ) and the motion detection device ( 62 ). Laser scanner ( 5 ) for scanning an environment ( 1 ) with a number of objects ( 2 . 3 . 4 ) with a control and processing unit ( 50 ), which are used to detect the position of a respective marker ( 7 . 8th . 9 . 10 ) according to one of claims 15 to 17 in step b) is formed. Laser scanner ( 5 ) according to claim 18, which is adapted to receive and process a signal or message by means of which the laser scanner (s) ( 5 ) a respective position of the marker ( 7 . 8th . 9 . 10 ) can determine. Laser scanner ( 5 ) according to claim 18 or 19, which is adapted to receive and process a signal or a message by means of which the laser scanner (s) ( 5 ) a respective identification date of the marker ( 7 . 8th . 9 . 10 ) can determine. Laser scanner ( 5 ) according to any one of claims 18 to 20, wherein the control and computing unit is adapted to a respective marker ( 7 . 8th . 9 . 10 ) in a point cloud generated by scanning and to identify. System for creating a three-dimensional model of an environment ( 1 ) with a number of objects ( 2 . 3 . 4 ), whereby the system has at least three markers ( 7 . 8th . 9 . 10 ) according to one of claims 15 to 17 and a laser scanner ( 5 ) according to any one of claims 18 to 21.

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