Method for determining at least one staking position

Abstract

Method for determining at least one staking position (4) in a robot cell (3) of a plant, in particular a factory, wherein positions within the robot cell (3) are referenceable based on a robot coordinate system (7) and positions within the plant are referenceable based on a plant coordinate system (6).

Description

[0001] The invention relates to methods for determining at least one staking position in a robot cell of a system, in particular a factory, wherein positions within the robot cell can be referenced based on a robot coordinate system and positions within the system can be referenced based on a system coordinate system.

[0002] Methods for determining staking positions, for example, within a factory environment, are generally known from the prior art. Typically, positions or spatial points or coordinates are specified in the coordinate system of the plant, also referred to as the "plant coordinate system," in order to be able to position devices, such as robot devices and the like, in relation to the plant. Individual components of the robot cell or the robot operating there are usually specified in coordinates of a robot coordinate system that is specific to the robot cell and not linked to the plant coordinate system.

[0003] In other words, when setting up the system, staking positions can be determined in the system coordinate system so that the individual devices of the system, for example, the robot arranged in the robot cell, can be located based on the system coordinate system. Subsequently, the multitude of staking positions are discarded, particularly to avoid large data volumes, transmission errors, and the like. In this case, only those positions are stored or maintained in the system coordinate system that are necessary for the operation of the system, in particular the robot cell.

[0004] For example, a position of a robot in the robot cell can also be stored in the system coordinate system, so that the position of the robot in the system coordinate system is known for corresponding referencing, e.g. simulations and the like. If a change is to be made to the robot cell, for example if another device is to be arranged there, it is necessary to determine a setting position in the system coordinate system. Since the large number of setting positions in the system coordinate system was discarded, it is not easy to determine a setting position. Although individual positions still exist in the system coordinate system, these are usually hidden by the devices arranged there, e.g. the robot, and therefore cannot be used for position determination. The detectable positions orFeatures within the robot cell are typically only available in the robot coordinate system, so direct transformation into the system coordinate system is not possible. It is therefore necessary to first establish a relationship between the robot coordinate system and the system coordinate system, for example, graphically or model-based. Since positioning an element, such as free stationing, typically requires at least three positions, this represents a complex process.

[0005] Document DE 11 2021 007 989 T5 discloses a control device comprising a correction amount calculation unit for calculating a correction amount for the operation of a movable robot with respect to a work area. Document DE 11 2021 007 324 T5 discloses a teaching device for measuring markers installed in a work area with a visual sensor. Devices configured to calculate a target position are known from documents DE 10 2019 001 969 B4, DE 10 2016 213 663 A1, DE 10 2011 011 360 A1, and DE 100 48 097 A1.

[0006] The invention is based on the object of specifying a method for determining at least one staking position in a robot cell of a system, which method is improved compared to the above-mentioned method, in which in particular the referencing in the system coordinate system can be carried out based on reference points in the robot cell, which reference points are covered by the robot cell and thus not accessible for optical detection.

[0007] The object is achieved by a method according to claim 1 and a measuring device according to claim 9. The dependent claims relate to possible embodiments.

[0008] As described, the invention relates to a method for determining at least one staking position in a robot cell of a system, in particular a factory, wherein positions within the robot cell can be referenced based on a robot coordinate system and positions within the system can be referenced based on a plant coordinate system. In other words, the method is intended to determine a staking position that lies in a robot cell of a system, for example a factory. The staking position can be used, for example, for the construction of at least one further device within the robot cell or for a modification of an existing device, for example a robot arranged within the robot cell.In principle, positions within the robot cell can be referenced based on the robot coordinate system. For example, the individual components of a robot operating within the robot cell can be referenced based on the robot coordinate system. Specific positions or spatial points within the robot cell or generally within the system can be referenced based on the system coordinate system. Typically, those positions that can still be referenced using the system coordinate system within the robot cell are not externally accessible, i.e., they are concealed by at least one structure within the robot cell. Therefore, determining a position based on such positions is not easily possible, since they are particularly concealed by components of the robot cell and thus not accessible for optical detection.

[0009] The procedure is based on the following steps: - Determining reference points arranged within the robot cell in the robot coordinate system; - Transforming the coordinates of the determined reference points in the plant coordinate system; - Detecting the referenced reference points by means of a detection device positioned in the robot cell; - Referencing the detection device in the plant coordinate system based on the transformed coordinates of the reference points; - Marking out at least one marking position within the robot cell by means of the referenced detection device based on the system coordinate system.

[0010] In other words, reference points arranged within the robot cell are determined in the robot coordinate system. The reference points can, in principle, be any desired location, as long as a position within the robot coordinate system has already been determined or known for the reference point. For example, the reference point can refer to a section of the robot or any other structure within the robot cell, such as a flange, a mounting plate, and the like. Once the reference point(s) have been determined, their coordinates within the robot coordinate system are available, as these are used, for example, for the operation of the robot or are known from the structure of the robot or robot cell.

[0011] The reference points are then transformed from the robot coordinate system into the system coordinate system. For example, at least three reference points can be used for this purpose to subsequently enable reliable positioning, in particular of an optical detection device or, more generally, a staking device, within the robot cell based on the reference points. The transformation can be based, in particular, on the fact that the determined reference points are not known in the system coordinate system, but are known in the robot coordinate system. For this purpose, at least one spatial point or position in the robot coordinate system is used, which is also known in the system coordinate system, but may not be optically detectable.Knowing the coordinates of the known spatial point of the robot coordinate system in the system coordinate system, the coordinates of the other reference points present in the robot coordinate system can be determined and transferred to the system coordinate system. In other words, knowing the relative position to the spatial point known in both coordinate systems, the reference points unknown in the system coordinate system can also be transformed into the system coordinate system. Based on the described transformation, the coordinates of the specific reference points in the system coordinate system can be determined, and the specific reference points can therefore be referenced in the system coordinate system.

[0012] The referenced reference points are then detected by a detection device positioned in the robot cell. In other words, the referenced reference points, which are optically detectable as described, can be detected, for example, by optical detection. Based on this, the detection device positioned within the robot cell can be referenced in the system coordinate system, namely based on the transformed coordinates of the reference points. Thus, the relationship between the reference points in the robot coordinate system and the at least one position in the robot coordinate system that is simultaneously known or referenced in the system coordinate system is utilized.

[0013] This allows referencing within the system coordinate system, specifically from reference points that were not actually known in the system coordinate system. However, such a reference can be established by relating them to at least one spatial point of the robot cell that is known in the system coordinate system. This takes advantage of the fact that the reference points, which are optically detectable but originally have no reference in the system coordinate system, can be detected by the detection device, thus enabling referencing of the detection device.

[0014] Subsequently, the at least one staking point or the at least one staking position can be staked out within the robot cell, namely using the referenced detection device based on the system coordinate system. In other words, the position of the detection device arranged in the robot cell can be referenced by referencing or transforming the coordinates of the determined reference points into the system coordinate system. Reference points of the robot coordinate system can then be recorded, thereby ensuring the positioning of the detection device. The staking position is then staked out directly in the system coordinate system.

[0015] According to one embodiment of the method, it can be provided that the detection device is referenced by means of free positioning in the robot cell. The term "free positioning" is understood in the context of the application to mean that the detection device, for example, a staking device, can be freely positioned within the robot cell and can then be referenced in the system coordinate system based on the method described above. Advantageously, therefore, the detection device does not have to be positioned at a specific position within the robot cell, for example, a position known in the system coordinate system, but can be arranged freely within the robot cell to establish the staking position.

[0016] Furthermore, the method can provide for the reference points to belong to at least one object in the robot cell, in particular to object features of at least one object. The object can in particular form a section of the robot or of a further device or structure within the robot cell. For example, object data can be available for the object, for example the arrangement of individual object features, for example drill holes, screw holes, edges, corners and the like. With knowledge of the positioning of the object features, in particular in the robot coordinate system, a reference can then be made to a spatial point present in the robot coordinate system, which is also known in the system coordinate system, for example a zero point of a robot in the robot cell.

[0017] As described, at least one object feature of at least one object in the robot cell can be used for referencing or for which at least one reference point is available. In a further development of the method, at least one object feature of at least one object can comprise an object position and / or an object orientation. The object feature can, for example, relate to a recess or bore or similar features of the object. For example, the object feature can comprise the object position, i.e. where the object feature is arranged in the robot coordinate system. Alternatively or additionally, the object feature can comprise the object orientation, i.e. how the object feature is aligned, for example how the longitudinal axis of a recess or bore is oriented in space, in particular in the robot coordinate system.

[0018] Furthermore, the method can provide for the at least one object, in particular at least one object feature, to be manually defined or read from at least one memory. The object or the object feature can, for example, be read from a memory of a higher-level control device which is designed at least to control the operation of the robot cell or at least one robot arranged therein. For example, the individual objects within the robot cell are stored in the control device or its memory for controlling operation or simulation of the device in the robot cell. Alternatively, it is also possible to manually define the object or the at least one object feature of the object, for example by manually entering a position of the object feature in the robot coordinate system.The individual object features can, for example, represent sizes, lengths, positions, orientations, and the like of individual features of the object, such as edges, corners, holes, screws, and the like. In particular, such data can be retrieved for existing objects, for example, loaded from the memory of the control device. These are modeled, for example, within the framework of models, so that such object features can be exploited.

[0019] According to a further development of the method, it can be provided that a measurement object, in particular a prism, which can be detected by the detection device is arranged in the at least one reference point. The measurement object can in principle be of any design as long as it can be detected by the detection device, in particular an optical one. Prisms which can be optically detected, for example by means of a tachymeter, such as round prisms or the like, are particularly suitable as measurement objects. In other words, the measurement object can be arranged in the reference point or relative to the reference point in order to be detected in order to determine the reference point. If the reference point represents a borehole, for example, it can be detected more effectively with the optical detection device if a dedicated measurement object, in particular a prism, is arranged in the reference point.Any deviation that may occur between the reference point and the position of the detected measuring object can be taken into account using a measuring object vector or prism vector, for example if the measuring object is arranged on a holder that is arranged at the reference point.

[0020] For this purpose, the method can specifically provide for a positioning and / or orientation of the measurement object to be determined based on at least one object feature of the object comprising the reference point. As already described above, the object features can include the position and / or orientation of the reference point or of the object that represents the reference point. Thus, for example, the position and orientation of a borehole that is used as a reference point can be included as an object feature. This results in how a measurement object holder arranged in the borehole is aligned and in which position the measurement object is located relative to the actual reference point, for example a center point of the borehole. Thus, the positioning and / or orientation of the measurement object can be determined based on the object feature of the reference point orof the object comprising the reference point, for example as a measuring object vector, which is calculated with the reference point in the robot coordinate system and can thus be transferred to the system coordinate system.

[0021] The method further provides that a stationing position of the detection device is determined based on the reference points in the robot coordinate system detected by the detection device and is referenced in the system coordinate system by transformation, in particular based on the measurement object vector of the measurement object. This allows, for example, the detection device to be freely stationed within the robot cell, so that the reference points within the robot cell can be detected by the detection device.Since, as already described, the reference points are also referenced in the plant coordinate system by the transformation into the plant coordinate system, the stationing position can also be transformed into the plant coordinate system, in particular taking into account the measuring object vector of the measuring object, via which the position recorded by the recording device is related to the reference point.

[0022] As described, the reference points can be transformed from the robot coordinate system into the system coordinate system via a transformation. The method can provide for the transformation of the reference points from the robot coordinate system into the system coordinate system to be based on (XBAYBRZBR)=(XRAYRAZRA)+RotxA(α)∗RotyA(α)∗RotZA(α) is determined. (XBAYBRZBR) the position in the plant coordinate system and (XRAYRAZRA) the position of the robot or the position in the robot cell, which is known in the system coordinate system. (xBRyBRzBR) denotes the position of the reference point, for example, the object. The rotation matrices are generally known. Furthermore, if the measurement object is not positioned at the reference point, a vector can be added that takes into account the deviation between the reference point and the position of the measurement object.

[0023] In addition to the method, the invention relates to a surveying device with a detection device, in particular an optical detection device, which is designed to carry out the method described above. The surveying device thus provides, in particular, a previously described control device that is designed to carry out the transformation. The control device can comprise a suitable computing device for this purpose. The described control device is connected to the detection device, which can be designed as an optical detection device, specifically as a tachymeter.

[0024] All advantages, details, designs and / or features described with regard to the method are fully transferable to the measuring device.

[0025] The invention is explained using exemplary embodiments with reference to the figures. The figures are schematic representations and show: Fig. 1 a schematic diagram of a measuring device in a factory environment according to an embodiment; and Fig. 2 a schematic diagram of a flowchart of a method for determining a staking position according to an embodiment.

[0026] Fig. 1 shows a schematic view of a surveying device 1 intended for surveying a work environment 2, in particular a robot cell 3. By means of the surveying device 1, in particular, at least one staking position 4 or any staking positions 4 in the robot cell 3 can be determined, in particular displayed and / or marked in the robot cell 3. For this purpose, the surveying device 1 has a detection device 5, which can be designed, for example, as an optical detection device, in particular as a tachymeter. In addition to the detection device 5, the surveying device 1 also has a control device (not shown in detail), which can be designed to control the operation of the detection device 5 and in particular also of the robot cell 3.

[0027] As in Fig. 1, the work environment 2, which can also be regarded as a plant, is assigned a plant coordinate system 6, via which positions within the work environment 2 or the plant can be referenced. The plant coordinate system can also be generally referred to as a plant coordinate system. Within the robot cell 3, a robot coordinate system 7 is shown, by means of which positions in the robot cell 3 can be referenced. For example, the plant coordinate system 6 is used to construct the robot cell 3, in particular a robot 8, so that the robot cell 3 can be constructed in relation to the work environment 2, for example to a work zero point or plant zero point. Typically, in such a process, in particular the construction of the work environment 2, existing staking positions are subsequently discarded except for a few positions in order to keep the amount of data low and minimize possible transmission errors.In other words, the structures of the robot cell 3 are largely not referenced in the system coordinate system 6, but only in the robot coordinate system 7.

[0028] Nevertheless, for a few specific structures or objects, such as the origin or zero point of the robot 8, at least one position 9 exists in the system coordinate system 6, which is referenced in the system coordinate system 6, for example a zero point. However, as shown by the dashed line, this position is obscured by the robot 8, so that it can no longer be detected by the detection device 5. Likewise, position 9 may be an undetectable position, for example an abstract zero point that has no physical form. If the detection device 5 is to be referenced within the robot cell 3, this is only possible in the robot coordinate system 7, since all structures of the robot cell 3 are only referenced in the robot coordinate system 7, and the exemplary position 9, for example a base plate of the robot 8 or its zero point, is not visible to the detection device 5.

[0029] Since the staking position 4 is usually to be determined for a change in the robot cell 3, in particular for the provision of a new device for the robot cell 3, referencing in the system coordinate system 6 is necessary. To determine the staking position 4, the method described herein can be carried out. This is shown as a schematic flow diagram in Fig.2 and starts in a block 10. There, reference points 11 arranged within the robot cell 3 are provided, which are referenced in the robot coordinate system 7. In block 12, the reference points 11 are transformed into the system coordinate system 6, namely based on the position 9, which is referenced or known in both the robot coordinate system 7 and the system coordinate system 6. In other words, the reference points 11 can be transformed into the system coordinate system 6 using the coordinates of the reference points 11 in the robot coordinate system 7, knowing their relative positions to the position 9 and the coordinates of the position 9 in the system coordinate system 6.

[0030] The reference points 11 referenced in the system coordinate system 6 can then be detected using the detection device 5. For example, the reference points 11 can be referenced by objects in the robot cell 3, for example the centers of boreholes and the like, which are visible to the detection device 5. In principle, any parts of the robot cell 3 can be used as reference points 11 or objects that have reference points 11. By detecting the reference points 11, in particular at least three reference points 11, the position of the detection device 5 within the robot cell 3 can be determined in a block 13, specifically in the system coordinate system 6. Subsequently, in block 14, it is possible to stake out the staking point 4 using the detection device 5, which, as described, is referenced in the system coordinate system 6.

[0031] This allows, in particular, free stationing of the detection device 5 within the robot cell 3, since it can be positioned as desired and subsequently referenced in the system coordinate system 6, as previously described. The object having the reference points 11 can be a known object, which is either specified manually or determined from a memory of the measuring device 1. This can, for example, be a standard component whose object characteristics are known. To further improve the optical detection of the reference points 11, a measuring object can be provided which can be coupled to the reference points 11 or the objects having them. For example, a prism can be inserted into boreholes directly or by means of a holder, or can be coupled in some other way to the object within the robot cell 3 that can be detected by the detection device 5.The position of the measuring object can then be included in the transformation into the system coordinate system 6 via a vector, in particular the prism vector.

[0032] The advantages, details and features shown in the individual embodiments can be combined with one another as desired, are interchangeable and transferable to one another. List of reference symbols 1 measuring device 2 Work environment 3 robot cell 4 staking position 5 Recording device 6 Plant coordinate system 7 Robot coordinate system 8 robots 9 positions 10 blocks 11 Reference point 12-14 blocks

Claims

[1] Method for determining at least one staking position (4) in a robot cell (3) of a plant, in particular a factory, wherein positions within the robot cell (3) are referenceable based on a robot coordinate system (7) and positions within the plant are referenceable based on a plant coordinate system (6), the method comprising the steps: - determining reference points (11) arranged within the robot cell (3) in the robot coordinate system (7); - transforming the coordinates of the determined reference points (11) in the plant coordinate system (6); - detecting the referenced reference points (11) by means of a detection device (5) positioned in the robot cell (3); - Referencing the detection device (5) in the system coordinate system (6) based on the transformed coordinates of the reference points (11), wherein a stationing position of the detection device (5) is determined based on the reference points (11) detected by the detection device (5) in the robot coordinate system (7) and is referenced in the system coordinate system (6) by transformation, in particular based on the vector of the measurement object; - Marking out at least one marking position (4) within the robot cell (3) by means of the referenced detection device (5) based on the system coordinate system (6). [2] Method according to claim 1, characterized by that the detection device (5) is referenced by means of free stationing in the robot cell (3). [3] Method according to claim 1 or 2, characterized bythat the reference points (11) belong to at least one object in the robot cell (3), in particular object features of at least one object. [4] Method according to claim 3, characterized by that at least one object feature of at least one object comprises an object position and / or an object orientation. [5] Method according to claim 3 or 4, characterized by that the at least one object, in particular at least one object feature, is manually defined or read from at least one memory. [6] Method according to one of the preceding claims, characterized by that a measuring object, in particular a prism, which can be detected by means of the detection device (5) is arranged in the at least one reference point (11). [7] Method according to one of the preceding claims, characterized bythat a positioning and / or an orientation of the measuring object is determined based on at least one object feature of the object comprising the reference point (11). [8] Method according to one of the preceding claims, characterized by that the transformation of the reference points (11) from the robot coordinate system (7) into the system coordinate system (6) is based on (XBAYBRZBR)=(XRAYRAZRA)+(xBRyBRzBR)∗RotxA(α)∗RotyA(α)∗RotzA(α) is determined. [9] Surveying device (1) with detection device (5), wherein the surveying device (1) is designed to carry out the method according to one of the preceding.

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