Probe for optical shape detection and / or surface inspection of a component, test setup and test procedure

Abstract

Probe head (101) with a housing part (101A) for optical shape detection and / or surface inspection of a component (B) n ) comprehensive - at least one camera (K0) with at least one lens for recording image data of at least one measurement area image of a measurement area image sequence of a component surface of the component (B) n ), - at least one switchable lighting element (101B) as a light source for illuminating at least one area of ​​the component surface of the component (B n ) during the recording of the at least one measurement range image, wherein - the at least one illumination element (101B) outside the north pole of a hemispherical scattering body (101D) opposite a measuring plane (ΔS) Bx x ΔS By ) of the measurement range image is arranged at an angle and - that at least one lens of the camera (K0) is arranged relative to the scattering body (101D) such that the lens of the camera (K0) through the viewing aperture (101D-1) of the scattering body (101D) illuminates the illuminated area of ​​the component surface of the component (B) at its north pole n ) parallel to the measurement plane (ΔS Bx × ΔS By ) of the measurement range image, characterized in that - a diffuser element (101B-1) is assigned to the at least one lighting element (101B), which scatters the light emitted by the at least one lighting element (101B), which then strikes an inner wall of the housing part (101A) at a predefinable angle, wherein - the inner wall of the housing part (101A) is coated to scatter the light, so that the inner wall acts as a light reflector (101G) and as a scattering element, and the scattered light is emitted from the inner wall at a reflection angle, which then points onto a component (B) n ) far-facing surface of the scattering body (101D) hits, - wherein the scattering body (101D) distributes the light passing through it on the exit side of the scattering body (101D), which is directed onto the area of ​​the component surface of the component to be illuminated (B). n ) meets.

Description

[0001] The invention relates to a probe head for optical shape detection and / or surface inspection of a component, and to a test setup with such a probe head. The invention further relates to a method for optical shape detection and / or surface inspection of a component, in particular based on the shape-from-shading method, which uses the probe head.

[0002] For surface testing, specific solutions are always developed depending on the various surface testing tasks, and these solutions are precisely tailored to the specific testing requirements. For example, significant effort is invested in developing technical solutions suitable for different surface properties, such as reflective surfaces (painted surfaces) or matte surfaces.

[0003] Well-known methods include deflectometry, stereometry, and shape-from-shading with a static setup. Shape-from-shading methods determine changes in slope or flat structures (low depressions, slight elevations with a small slope). Subtle changes in reflected light intensity are analyzed to deduce the respective slope of the reflecting areas, given a known geometric arrangement between the camera, object, and light source.

[0004] Due to the nature of the process, deflectometry can only be used to test reflective surfaces, such as painted surfaces.

[0005] Previously known approaches to the shape-from-shading method are, as far as is known, only used for matte, not for reflective surfaces.

[0006] As technological background to the invention, reference is first made to US Patent 5,051,872 A. It describes a diffuser arrangement for shadowless illumination of an object, comprising the following: a translucent diffuser with a substantially hemispherical, concave surface; a diverging lens arranged at a distance from the diffuser, which shapes and directs the light onto it; a light source positioned to direct light rays through the diverging lens and into the optical medium of the diffuser; wherein substantially all light rays incident at the center of curvature of the concave surface pass through the translucent diffuser.

[0007] The publication WO 2004 / 051 186 A1 (EP 1 567 827 B1) discloses a method for the optical shape detection and / or evaluation of optically smooth, glossy, or optically rough surfaces. The method is characterized by the combination of a photometric stereo method, a deflectometric method, and a scattering body in such a way that the locations on the scattering body surface are encoded area by area.

[0008] German patent application DE 203 17 095 U1 is known, which presents a device for detecting defects on the surface of an object, comprising a light source for illuminating the object with a beam of light falling on the object at an angle of incidence to the surface; a light detector for detecting a beam reflected from the object surface onto the illuminating beam, which is reflected from the object at an angle of refraction to the object surface, the angle of refraction being equal to the angle of incidence, in order to obtain image data; and an evaluation device for evaluating the image data in order to detect possible defects.The finding is that a very high-contrast image of an object surface, and thus a facilitated and / or reliable evaluation of the image data to detect surface defects, is possible if the lighting device and the detection device are arranged in such a way to the surface to be inspected that the angle of incidence of the lighting beam to the surface has the same angle as the angle at which the detection beam is inclined to the surface, i.e., the gloss angle condition is met, since this results in a very high-contrast image in which defective and defect-free surface areas differ greatly in their brightness.

[0009] German patent application DE 10 2004 038 761 A1 concerns a camera-based inspection of an object illuminated by at least one light source. In this process, a camera captures an object illuminated by a light source, and the image data is processed. The processing employs the shape-from-shading method, in which the object's surface is reconstructed by minimizing a cost function. To avoid unwanted reflections at the object's edges and surfaces, only parts of the object are illuminated by the light source. The image areas to be processed are chosen in such a way that the shape-from-shading cost function could be optimally adapted to the target geometry within these areas, assuming the object in those areas corresponds to the target geometry.Alternatively, support point values ​​can be defined and specified within the image areas in such a way that the cost function of the shape-from-shading is divided into discrete sections when guided through these support points, so that it could be adapted as optimally as possible to the target geometry if the object corresponds to the target geometry in these areas.

[0010] Furthermore, reference is made to publication EP 1 949 673 B1, which describes a method for recording a number of images of an object in rapid succession with at least one camera using at least three different phase positions of structured illumination, namely a fringe pattern or an interference pattern, wherein the phase positions are operated spatially adjacent to each other, wherein the object is moved relative to the structured illumination so that a certain feature of the object lies in the different phase positions of the structured illumination at different times, wherein a speed of movement of the object and / or a time of readout processes is / are chosen such that the test object moves by a pixel distance or a multiple thereof between two readout processes, and that for each phase position in which the feature lies,The same number of lines of the camera chip are read, wherein for each phase position in which the feature lies, only a sub-area of ​​the camera chip is read, namely as many lines of the camera chip as there are images with different phase positions to be recorded or a multiple thereof, and wherein the short temporal sequence is short compared to a temporal sequence that can be achieved by reading all lines of the camera chip.

[0011] Also known is a lighting system described in publication EP 1 864 081 B1, which is also based on a hemisphere, wherein the hemisphere is designed as a completely opaque diffusing body and thus serves exclusively as a reflector, which is used for optical shape measurement and / or optical testing of objects.The lighting system comprises at least one camera, at least one lens, the opaque diffuser (hemisphere) with at least two light sources arranged inside the diffuser, wherein an inner surface of the diffuser is illuminated by one or more of the light sources, which can be switched on individually or in groups independently of each other, such that the at least two light sources are positioned outside the center of the diffuser in such a way that the inner surface of the diffuser is illuminated along a line extending from a point on the equator of the diffuser towards its north pole and further to an opposite point on the equator with continuously increasing or continuously decreasing illuminance when at least one of the light sources is switched on.

[0012] Also known is publication WO 2015 / 000898 A1, which discloses a method for optically detecting and / or inspecting the shape of an object, as well as a device for optically detecting and / or inspecting an object. The method and the device are suitable for detecting and / or inspecting objects with optically rough surfaces and / or glossy surfaces, up to and including optically smooth surfaces. The process involves the stepwise arrangement of at least one camera, at least one linear illumination element, and an object relative to each other such that an object surface can be illuminated by the at least one illumination element and recorded by the camera.- Inducing a relative movement between at least two elements selected from a group consisting of the object, the at least one illumination element, and the camera, wherein one direction of movement with the at least one illumination element includes an angle other than 0°; - Recording a sequence of images of the object surface with the camera during the relative movement, wherein the object surface is imaged in an image plane of the camera; - Illuminating the object surface with the at least one illumination element during the exposure of the image plane; and - Evaluating the recorded image sequence with regard to local surface inclinations and / or local optical properties of the object surface.

[0013] Furthermore, German patent application DE 10 2011 117 894 A1 describes a device for optically detecting the shape of a moving object, comprising at least one lighting device, wherein the lighting device is designed and / or arranged in such a way that it can produce different illuminations of the object to be detected, and at least one recording device, which is designed and arranged in such a way that it can capture images of the object. The device is characterized by a control device by which a movement of the object can be controlled using a movement device.

[0014] One disadvantage of the known solutions is that the diffusivity of the light emitted by the lighting elements is not sufficient for glossy surfaces, for example painted ones, where, depending on the type of paint, diffuse scattering (optically rough surface) and mostly glossy to reflective components occur, in order to adequately suppress reflections from the light sources, especially light-emitting diodes (LEDs), on the component being tested.

[0015] Furthermore, all known solutions for devices and the associated procedures are very time-consuming and complicated in design, and therefore hardly suitable for series production.

[0016] The invention is based on the objective of creating a method and a device for optical shape detection and / or surface inspection of components with different geometric freeform shapes, in particular based on the shape-from-shading method, which are suitable for series production and thus ensure short inspection times for the variably inspectable components, wherein the method and the device should achieve a high-quality inspection result for different surface properties, in particular reflective, especially painted surfaces and matte surfaces.

[0017] According to claim 9, the invention relates to a method for optical shape detection and / or surface inspection using a probe head according to claim 1, comprising the following steps: - Arranging at least one camera, at least one lighting element and the component in a test setup such that at least one area of ​​a component surface, corresponding to at least one measuring area, is illuminated by at least one lighting element, - Recording a measurement range image sequence using the camera in several measurement ranges by a continuous movement of the camera relative to the component or vice versa, wherein the measurement ranges of the component surface are mapped in an image plane of the camera and simultaneously illuminated with the at least one illumination element in an associated illumination process while recording the images of the measurement range image sequence, - Evaluating the recorded images of the measurement range image sequence in at least one of the several measurement ranges of the component surface with regard to a changed local surface inclination and / or local optical properties of the component surface.

[0018] A significant advantage of the method according to the invention lies in the fact that, in a continuous movement of the camera relative to the component or vice versa, the component surface is "scanned" according to the aforementioned features, with a further significant advantage being that the light incident on the component does not cause any reflections on the component through the use of the probe head, since a diffuser element associated with a lighting element of the probe head suppresses the reflections of the light source to such an extent that measurement on matte and glossy surfaces of the component to be tested is possible.

[0019] In conventional methods, a measurement position is approached, the movement is then stopped, a series of images covering the measurement range is captured, and then the next measurement position is approached. This constant stopping and starting to create the image sequence results in significantly lower measurement speeds.

[0020] The starting point of the invention, according to claim 1, is a device comprising a probe head with a housing part for optical shape detection and / or surface inspection of a component using the method comprising - at least one camera with at least one lens for recording image data of at least one measurement area image of a measurement area image sequence of a component surface of the component, - at least one switchable lighting element as a light source for illuminating at least one area of ​​the component surface during the recording of the at least one measurement range image, wherein - that at least one illumination element is arranged at an angle outside the north pole of a hemispherical scattering body relative to a measurement plane of the measurement area image, and - that at least one lens of the camera is arranged opposite the scattering body in such a way that the lens of the camera captures the illuminated area of ​​the component surface of the component parallel to the measuring plane of the measuring area image through the viewing aperture of the scattering body at its north pole.

[0021] According to the invention, it is provided that - a diffuser element is assigned to the at least one lighting element, which scatters the light emitted by the at least one lighting element, which then strikes an inner wall of the housing part at a predefinable angle, wherein - the inner wall of the housing part is coated to scatter the light, so that the inner wall acts as a light reflector and as a scattering element, and the scattered light is emitted from the inner wall at a reflection angle, which then hits a surface of the scattering body facing away from the component, - wherein the scattering body distributes the light passing through it on the exit side of the scattering body, which hits the area of ​​the component surface to be illuminated.

[0022] Advantageously, the reflections of the light source(s) of the at least one illumination element are suppressed by reflection on the inner wall, in particular a cylindrical inner wall of the probe head, and subsequent transmission through an opaque hemisphere designed as a scattering body, to such an extent that measurement on glossy surfaces and also on matte surfaces of the respective component to be tested becomes possible.

[0023] Opacity is a measure of the light-blocking (cloudiness) of translucent (light-scattering) materials and layers. The light (in)transmittance of an opaque hemisphere as a scattering body is expressed as the transmission of electromagnetic waves. In other words, a portion of the light of a specific, predefined wavelength striking the opaque hemisphere passes through the material of the opaque hemisphere.

[0024] Testing on matte surfaces is also possible with the same probe in the test setup and associated method described below, so that with the probe according to the invention, both matte and glossy surfaces of the component to be tested can be advantageously detected within the test setup according to the invention.

[0025] In a preferred embodiment of the invention, the test head has at least one lighting element for adjusting the inclination relative to the measuring plane of the component, and at least one inclination adjustment element which is indirectly or directly connected to the housing part.

[0026] Preferably, the diffuser element is arranged on the lighting element.

[0027] Furthermore, it is preferably provided that a special white paint is used as a coating for the scattering and reflecting inner wall, which has a rough surface on its inside with a predefinable surface roughness.

[0028] Furthermore, the probe is characterized by a significant decrease in the wall thickness of the opaque hemisphere in the lower part (near the equator) towards the upper part (towards the North Pole). Various materials can be used to manufacture the opaque hemisphere. It is essential that the opacity is homogeneously distributed and remains homogeneous even when the material is thinned, for example, by a deep-drawing process.

[0029] In a preferred embodiment of the invention, the probe head is a hollow cylinder that completely and compactly accommodates the aforementioned components inside.

[0030] The invention further comprises, according to claim 7, a test arrangement characterized in that a robot-guided probe head is arranged opposite a component arranged for optical shape detection and / or surface inspection, wherein the probe head is guided by the robot to record a measurement range image sequence using the camera in several measurement ranges of the component by moving the camera opposite the component or vice versa.

[0031] Finally, according to the invention, the global position of the component for 6D component localization in space is determined with a position determination system, in particular a stereo camera system, and a 6D reference position is calculated, wherein at least one calibration is performed between a robot arm of the robot and the system, whereby a referencing of the component in three-dimensional space in its target position relative to the robot-supported probe head is achieved in a predefinable distance constancy between the probe head and the component surface.

[0032] The existing solutions can be described and viewed as static and non-dynamic, since the movement of the camera relative to the component or vice versa is not continuous when recording the measurement range image sequence, and therefore not in real time.

[0033] In a preferred embodiment of the invention, it is provided that the speed of the relative movement between the camera and the component is constant during the recording of the multiple images per measurement range image of the measurement range image sequence.

[0034] Furthermore, in a preferred embodiment of the invention, the speed of the relative movement between the camera and the component between the recordings of the multiple images per measurement range image of the measurement range image sequence is constant or variable.

[0035] Preferably, the global position of the component in space is captured three-dimensionally in a zero position before the measurement range image sequence is recorded using the camera and stored as the target position.

[0036] Furthermore, it is preferably provided that the distance of the component relative to the camera is maintained at a predetermined distance from the target position of the component, depending on the component size, and that the predetermined distance is maintained within a predefinable distance accuracy during the continuous movement.

[0037] In a preferred embodiment of the invention, as mentioned, it is provided that for each image of the measurement range image sequence several images are taken, which are then combined according to the invention to form the measurement range image of the component representing the at least one measurement range.

[0038] According to the invention, the procedure is as follows: the recordings of the multiple images of the measurement range image sequence of the multiple two-dimensional measurement ranges of the detected component surface have an overlap length relative to each other.

[0039] Furthermore, it is preferably provided that each measuring area is assigned a two-dimensional measuring location, in whose entire image area the measuring plane as a depth of field condition deviates from the component contour of the component by a maximum of the depth of field, wherein the camera is aligned orthogonally to the two-dimensional measuring location, and a predefinable tolerance of the inclination to the measuring plane is maintained with regard to orthogonality.

[0040] The method is further characterized by the fact that each of the multiple images of the measurement range image sequence is taken within an exposure time on a plateau with constant luminous flux and a predefined nominal luminous flux.

[0041] It is also preferred that the start of each first recording of the multiple images of each image of the measurement range image sequence is carried out by a trigger in a path-synchronous manner, depending on the relative movement of the camera to the component or vice versa, so that the overlap length is constant.

[0042] In particular, it is provided that a master trigger signal, as soon as the camera is at the position designated for a first recording of the multiple images of each image of the measurement range image sequence depending on the path-synchronous control, triggers a trigger chain, whereby by means of a slave trigger lighting the at least one lighting element of the at least one lighting device the associated lighting process and, at a time offset, a slave trigger camera of the camera is controlled and started, by means of which an image recording is carried out within the plateau, after which the next master trigger signal is triggered.

[0043] The procedure is preferably characterized by the following steps: In a first step a), the multiple images of each image of the measurement range image sequence are recorded within an integrated circuit.

[0044] In a second step b), a displacement correction of the pre-planned superimposed measurement ranges is performed within the integrated circuit, preferably correcting unplanned inaccuracies in addition to the pre-planned overlap. This is achieved by "floating" the images of each image of the measurement range image sequence and the measurement ranges relative to each other through a displacement correction, after the individual image sections have been transferred to a processor for calculating a displacement correction. The result is sent back to the integrated circuit as correction data, so that the displacement is carried out within the integrated circuit.

[0045] In a third step c), the albedo is calculated as a measure of the reflectivity of the component surface in at least one of the several measurement areas using a shape-from-shading algorithm.

[0046] In a fourth step d), the result of the calculation of the Shape-from-Shading algorithm is filtered and corrected using appropriate filter and correction algorithms.

[0047] In a fifth step e), an analysis of the measurement ranges is carried out with regard to areas of particular interest and a masking is performed.

[0048] In a sixth step f), the areas of interest will be provided with local coordinates that correspond to the relevant surface defects on the component surface of the respective component, whereby the local coordinates are passed on to the processor for further calculation.

[0049] In a preferred embodiment of the invention, it is further provided that in a seventh step g) a defect detection takes place in which the potential defects are identified.

[0050] In an eighth step h), the potential defects are parameterized according to certain predefinable parameters, in particular the size, and classified into defect classes.

[0051] In a ninth step h), actual defects are classified starting from the potential defects.

[0052] In a tenth step i), the global coordinates of these real defects are determined from the local coordinates of a measuring area according to the global position of the component according to claim 12, wherein the local coordinates of the real defects in the respective two-dimensional measuring area are "mapped" three-dimensionally onto the multiple measuring areas of the component, so that the real defects are arranged exactly in three-dimensional space on the component having a three-dimensional freeform shape.

[0053] The actual defects “mapped” in step j) are visualized and displayed on a monitor after being transmitted to a graphics card.

[0054] Finally, in a last twelfth step k), the “mapped” actual defects are stored in defect tables with appropriate localization, defect type and defect size, and made available for further evaluation.

[0055] Unless otherwise stated in individual cases, the various embodiments of the invention mentioned in this application can be advantageously combined with one another.

[0056] The invention is explained below using exemplary embodiments with reference to the accompanying drawings. These show: Fig. 1 the testing system according to the invention for surface testing of a component, in particular of an exemplary illustrated bumper; Fig. 2 an external view of a probe of the test system; Fig. 3 a schematic diagram illustrating a lighting device and light guidance within the test head of the test system; Fig. 4A a perspective view of the internal structure of the cutaway probe; Fig. 4B a perspective view of the lighting elements of the lighting device within the probe head; Fig. 5 a schematic representation (top view) of an arrangement of the LEDs preferably used as lighting elements within the lighting device; Fig. 6 a schematic representation (side view) of the lighting elements; Fig. 7 a schematic representation (side view) of the lighting elements; Fig. 8 a schematic representation of an arrangement of cameras within a camera system according to the stereo camera principle for controlling distance constancy; Fig. 9 a presentation as well as definition and nomenclature of time periods that are taken into account within the test duration of the dynamic surface testing of components; Fig. 10 a representation as well as definition and nomenclature of image sizes, measuring ranges and overlapping areas within an image acquisition method according to the invention; Fig. 11 a basic representation of several overlapping measurement windows; Fig. 12 a definition and nomenclature of a two-dimensional arrangement of multiple measurement windows within the image acquisition procedure; Fig. 13 the arrangement of a camera of a camera system at an intolerable inclination to the component to be inspected; Fig. 14 the arrangement of the camera in an orthogonal arrangement with respect to the component to be inspected; Fig. 15 a diagram to explain the importance of positioning the camera, taking into account depth of field within the measurement area; Fig. 16 a timing control of the image acquisitions between two successive measurements within the image acquisition method by means of the illumination device provided according to the invention; Fig. 17 a definition and nomenclature of the illumination parameters within the image acquisition procedure using the illumination device; Fig. 18 a representation of a trigger concept for image processing of the images taken by means of the lighting device within the image acquisition procedure; Fig. 19 a representation of the configuration of a control device of the method for dynamic testing of a component surface, in particular for the representation of a trigger and communication concept; Fig. 20 a schematic representation of the software concept required for evaluation; Fig. 21 a schematic representation of the software concept, in particular the FPGA functions according to the Fig. 19 and Fig. 20; Fig. 22 a schematic representation of the software concept, in particular the GPU functions according to the Fig. 19 and Fig. 20; Fig. 23 a schematic representation of the software concept, in particular the CPU functions according to the Fig. 19 and Fig. 20. Testing system:

[0057] Fig. Figure 1 shows the test system 100 according to the invention for surface testing of a component B, in particular of an exemplary bumper.

[0058] The plan is to use one or more robot-guided scanning inspection systems in parallel.

[0059] The inspection of component B n In the exemplary embodiment, this is done on a component carrier T, in other words, the component B n In the selected embodiment, it is fixedly arranged on / at a component support T during the test. Probe head and light guide:

[0060] The robot-assisted testing system 100 includes a probe 101 as a key component. The probe 101 of the testing system 100 is moved relative to component B by an industrial robot 200. n guided, moved.

[0061] The Fig. Figure 2 shows an external view of the probe 101, with a hollow cylindrical housing part 101A shown transparently.

[0062] In the upper area of ​​the hollow cylindrical housing part 101A a camera K0 and at least one lighting element 101B are arranged.

[0063] An opening is provided in the upper section to ensure ventilation of housing part 101A, particularly for heat dissipation. Camera K0 is seated in a receptacle located in housing part 101A, which allows for fine-tuning of the camera K0's position.

[0064] In the lower region of the hollow cylindrical housing part 101A, a spherical opaque light diffuser 101D is arranged, which is attached to the inside of the hollow cylindrical housing part 101A. The hemisphere has a viewing opening 101D-1 centrally located within the hemisphere 101D, extending along the longitudinal axis of the camera K0, above which the lens of the camera K0 is arranged.

[0065] In Fig. Figure 3 schematically illustrates the lighting principle or light guidance, which is realized through a special design of the lighting device within the test head 101 of the test system 100.

[0066] The at least one lighting element 101B emits light, which is first scattered by a diffuser element 101B-1, in particular a diffuser plate. The light is then emitted at a predefinable angle onto the inner wall of the hollow cylindrical housing part 101A. Tilt adjustment elements 101E (see Figure 1) are used to adjust the tilt of the at least one lighting element 101B. Fig. 4B), which are connected to the at least one lighting element 101B and are attached to at least one carrier plate 101F.

[0067] The inner wall of the hollow cylindrical housing part 101A is coated with a special white paint - to create a rough surface - so that the inner wall of the hollow cylindrical housing part 101A is designed as a light reflector 101G with a predefinable scattering effect.

[0068] The light reflected from the cylindrical reflector 101G thus reaches the surface of the opaque hemisphere 101D at a predefinable reflection angle. The opaque hemisphere 101D prevents a portion of the incident light from passing through. The light that does pass through (transmission) is then distributed by the opaque hemisphere 101D at the exit side within the lower region of the hollow cylindrical housing part 101A.

[0069] The lighting device thus comprises at least one lighting element 101B with the diffuser plate, the reflector 101G and the opaque hemisphere 101D.

[0070] The opaque hemisphere is designed in such a way that the wall thickness in the lower part decreases significantly towards the upper part.

[0071] In conjunction with the partially absorbing properties of the opaque hemisphere, this achieves light quantity control, which is particularly suitable for applying the inventive method to components B. n is required for reflective surfaces.

[0072] The light emitted by the at least one fastening element 101B is thus scattered by means of the diffuser plate, the light reflector 101G and the opaque hemisphere 101D, so that the light falling on component B n Incident light causes no reflections on component B n thus causes. The reflections of the light source are suppressed to such an extent by the diffuser plate and by the reflection at the inner wall of the cylinder of the probe 101, which is designed as a light reflector 101G, and by the subsequent transmission of the light through the opaque hemisphere 101D, that, according to the invention, a measurement on glossy surfaces of the component B to be tested is possible. n becomes possible.

[0073] However, testing on matte surfaces is also possible with the same probe setup, so that both matte and glossy surfaces of the component to be tested can be advantageously detected with the probe setup.

[0074] The only details Fig. Figure 4B shows that two lighting elements 101B are arranged within the probe assembly, which illuminate the component B to be tested according to the principle described above. n illuminated. The Fig. Figure 4B additionally shows the diffuser plates as details, which are connected to the lighting elements 101B in the assembled state, as shown in particular in the Fig. 6 and Fig. 7 is shown.

[0075] The Fig. Figure 5 shows a lighting element 101B in a top view.

[0076] Due to the short exposure times required to minimize sensitivities to component vibrations, Δt b = 40 - 50 µs are high luminous fluxes Φ ν required for lighting. Component vibrations are transmitted, for example, via the floor to the clamping device in which component B is held. n clamped in the support T, onto the component B to be tested n transmitted, whereby the vibrations of the component surface are taken into account when recording the measurement range image sequence by short exposure times of the camera K0 of the probe head 101.

[0077] Light fluxes are measured between Φ ν N = 25,000 lm and Φ ν N = 80,400 lm used. Due to the high luminous flux and the reflective surface to be tested, only indirect, diffuse lighting can be used, as explained previously.

[0078] The lighting elements 101B preferably comprise several white LEDs with a maximum luminous flux of Φν N = 80,400 lm (nominal luminous flux of the LEDs at a supply voltage of 39.2 V and a supply current of 13.8 A). Alternatively, especially on very smooth surfaces, blue LEDs (blue light) can be used, taking into account the spectral conversion of the radiant power.

[0079] In the exemplary embodiment according to Fig. In section 5, twelve LEDs, particularly white ones, are combined to form a lighting element module consisting of several lighting elements 101B. In the assembled state, as the Fig. 6 and Fig. Figure 7 in side views shows heat sinks 101B-2 arranged above the lighting elements 101B and the diffuser plate already described below the lighting element 101B. The heat sinks 101B-2 are also shown in Fig. 4B is shown in perspective in a kind of exploded view, separated from the LEDs. Testing technology:

[0080] Each test system 100 (compare Fig. 1) checks the existing components B n in a so-called plant cycle.

[0081] As a testing technology or as a method for surface testing of a component B n The adapted Shape-from-Shading (SFS) is used, which according to the invention now works dynamically and is designed accordingly, as explained in detail below.

[0082] The required accuracy of component positioning of component B n The position of the probe 101 of the test system 100 relative to component B is approximately + / - 500 µm to 2 mm. n must correspond to the specified distance accuracy.

[0083] The depth of field range of cameras K1, K2 of a stereo camera system 102 (compare Fig. 8) is limited. The entire component area of ​​component B to be tested n must lie within the depth of field range, which is why the distance accuracy of approximately + / - 500 µm to 2 mm is of great importance, as will be explained later.

[0084] A robot path is programmed for all component types during commissioning, whereby the robot path determines the swiveling movement of the robot arm 201 and thus the probe path of the probe 101 relative to the component B. n is certain.

[0085] Component B n is in a zero position, the position of component B n Measurements are taken and stored in the room.

[0086] This metrological recording of the component position is only necessary if the tolerances of the component support are so large that the component surface could lie outside the depth of field range of cameras K1, K2.

[0087] In a measuring operation, the three-dimensional position of component B is determined. n in the room with the stereo camera system 102; K1, K2, schematically in Fig. Figure 8 shows the process immediately after the component B has been driven in and settled. n Measured using measuring equipment.

[0088] Subsequently, a deviation Δs is calculated. R the location of the current component B n a zero position is determined and from this a correction is calculated for the created program to control the robot 200 or its robot path.

[0089] The corrected program for controlling robot 200 is transferred to the robot controller. Robot 200 starts the component inspection with the corrected path. This correction is only necessary if the tolerances of the component support are so large that the component surface could lie outside the depth of field of cameras K1 and K2 of the stereo camera system 102.

[0090] The reach of robot 200, in particular of robot arm 201, must be large enough to cover all measurement locations M(i). x , i y ) can be achieved within a two-dimensional coordinate system.

[0091] Care is taken to ensure that the test system is positioned in a so-called measuring position at the measuring location. The robot 200 must have an accuracy that allows the test system 100 to operate with a distance accuracy of Δs. R The component is guided from ± 500 µm to 2 mm.

[0092] It is intended that the robot arm 201 will preferably follow the robot path continuously at a constant speed V. R departs, whereby the speed of the robot arm 201 can also vary in this process.

[0093] For each measurement to be carried out at the respective measurement location M(i x , i y ) a robot track support point with the analogous designation M(i x , i y ) programmed in two dimensions.

[0094] The robot controller sends a signal when the robot path support point M(i) is reached. x , i y ) a real-time trigger and location information.

[0095] Upon reaching the railway base M(i x , i y ) at the measurement location, the real-time trigger is sent, which initiates the execution of the measurement.

[0096] Similarly, the location information of the railway depot M(i) x ,), i.e., the location of the railway base M(i x , iy ) in the room, sent.

[0097] The path programming is executed in such a way that at each measuring point M(i x , i y ) the orientation of the inspection system is realized in such a way that the image size ΔS is used throughout the entire image area BX × ΔS B A measurement plane, as a depth-of-field condition, deviates from the component contour by a maximum of the depth of field, which will be discussed later.

[0098] If due to the local curvature of component B n If it is not possible to comply with the depth of field condition in the image area, the size of the image area can be reduced by agreement.

[0099] The resulting shifts in the measurement locations M(i x ,) for the following measurements are taken into account, as will also be explained later.

[0100] The robot arm 201 of the robot 200 may move four times Δt during the recording of all four images, including the transmission times of the images or the readout time from camera K0 and the transmission times of the images to the computer. K (see also) Fig. 18)) move only at a constant speed.

[0101] Changes in direction due to reorientation of the robot arm 201 of the robot 200 are avoided, whereby a predefinable constant speed only needs to be guaranteed until the fourth image has been captured. Even during the data transmission of the fourth image, the speed of camera K0 relative to component B can change. n The predefined speed between the created measurement range images of the measurement range image sequence can be set to be constant or can be changed, with several speed changes being possible. Distance consistency:

[0102] The Fig. Figure 8 shows a schematic representation of an arrangement of cameras K1 and K2 within a camera system KS according to the method principle of the stereo camera for controlling a distance constancy between component B. n and probe 101 of the test system 100 within the required distance accuracy of Δs R =± 500 µm to 2 mm.

[0103] This metrological recording of the component position is only necessary if the tolerances of the component support are so large that the component surface could lie outside the depth of field range of cameras K1, K2 of the stereo camera system 102.

[0104] Significant identification features will be found on component B. n to determine the 6D position of component B n fixed in space.

[0105] For position detection using stereo measurement, the two cameras K1 and K2 are used (compare Fig. 8) used, which have a fixed distance between them and are positioned at a predetermined slight angle towards component B n look.

[0106] The required distance between cameras K1, K2 and the image acquisition distance are largely determined by the size of component B. n determined.

[0107] For reliable 6D component localization in space (x, y, z, α, β, γ), at least three corresponding significant test features are determined, recorded in the camera images, and evaluated.

[0108] Suitable test features include, for example, openings arranged in different planes or similar features.

[0109] Based on this 6D component localization in space (x, y, z, α, β, γ), at least one calibration takes place between robot arm 201 and the two cameras K1, K2, thereby enabling the referencing of a component B. nis in its intended position in three-dimensional space.

[0110] Before the measurement begins, the position of component B is summarized. n The position in space (x, y, z, α, β, γ) is determined using the stereo camera system 102. The so-called 6D reference position is calculated and transmitted as a base shift to the robot R's control unit.

[0111] The base is the origin coordinate of the robot R. The position of component B. n was measured. If the position of component B n If the position of the robot R is shifted relative to the target position, it is assumed that the position of the robot R relative to the component B has changed. n has changed. To correct the displacement of component B n to correct the position relative to the target position, that is, component B n To bring it into the correct (corrected) starting position, the so-called base shift described above is performed. Time control:

[0112] Fig. Figure 9 shows a representation of time periods within the test duration of the dynamic surface inspection of components B. n be taken into account.

[0113] Definition and nomenclature: Δt H1 = first handling period Δt H2 = second handling period Δt Pges = Total testing time for the testing of one or more components B n This corresponds to the so-called cycle time. Δt P = Test duration per component B n During this period, component B will be installed. n Completely checked. This involves n M Measurements were carried out. Δt M = Measurement duration. A measurement is taken during this period. Several images are taken during each measurement (corresponding to the exposure time Δt). B ), in the exemplary embodiment four images in time Δt M recorded.

[0114] Number of measurements = n M ΔtB = Exposure time. An image is taken during this period. Δt R = Robot (arm) movement duration.

[0115] During this period, the robot arm 201 of the robot 200 moves from the last measuring position on component B1 to the first measuring position on component B2.

[0116] Δt K = Camera data transmission period. During this period, an image from camera K0 in the probe head 101 is transmitted to the frame grabber FPGA. ΔtP=ΔtPtot−ΔtH1−ΔtH2−ΔtR2ΔtM=ΔtPnM

[0117] The total test duration is Δt Pges = Beat time = for example 60s

[0118] The test duration per component is Δt. P = for example 25s ΔtH1+ΔtH2+ΔtR=10s ΔtB~40−50μs.

[0119] In the selected embodiment, this specification represents a desired exposure time Δt. B to understand. The exposure time Δt Bdepending on the color of the component being tested B n may deviate from the specified values. For darker components B n is the exposure time Δt B tends to be longer, especially approximately 60-100 µs, where the illumination duration Δt L to adjust accordingly (compare Fig. 17).

[0120] The exposure time Δt B is set as short as possible in order to eliminate disturbances caused by vibrations and oscillations of component B.

[0121] Fig. Figure 9 illustrates the basic procedure of a component test using two components as examples. n .

[0122] Fig. Figure 1 shows a time axis t. In the exemplary embodiment, two components B1 and B2 are tested in one machine cycle (cycle time). The component carrier T (compare Fig. 1) travels during the time interval Δt H1 into a testing station.

[0123] First, the first component B1 is tested. The testing duration per component B n Δt is P Then the robot arm 201 of the robot 200 moves during the time interval Δt. R for testing the second component B2 from the first component B1 to the second component B2. The component carrier T (compare Fig. 1) travels during the time interval Δt H2 out of the testing station.

[0124] Within the test period Δt P per component B n A component B will be n Completely tested. Several measuring ranges M are examined. n , so-called tiles in the time interval Δt M recorded, wherein in the exemplary embodiment n = 4 recordings M n in several measuring ranges M or tiles, depending on component size) in the time intervals Δt M to be carried out. This results in a test duration Δt. Pges total for the testing of one or more components B n, which corresponds to the so-called cycle time. Image capture concept:

[0125] Fig. Figure 10 shows a representation of image sizes in measurement areas and overlap areas within an image acquisition method according to the invention. Definition and nomenclature:

[0126] The image size of a tile or a measurement area / window M (i x , i y ) is defined as ΔS Bx ; ΔS By

[0127] The measurement range quantity is defined as ΔS Mx ; ΔS My

[0128] The recording offset between two measuring ranges / measuring windows is in particular ΔS A = 120 pixels and is constant, although other recording offsets are also possible.

[0129] The overlap length between two measuring ranges / measuring windows is ΔS in the exemplary embodiment. U = 10 pixels and is constant, although other overlap lengths are also possible.

[0130] The hatched measuring area M n is the area that corresponds to the images 1 to 4 created with the camera K0 arranged in the probe head 101 for all n = 4.

[0131] The in Fig. The overlap length ΔS is formed by the 10 frames shown. U between several measuring ranges M n (i x , i y ) or between two tiles. The overlap length ΔS U is important so that the multiple measuring ranges M n taking into account the overlap length ΔS U can be arranged next to each other.

[0132] The Fig. Figure 11 shows a basic representation of several overlapping elements with ΔS length. U overlapping measuring ranges / measuring windows M(i x , i y ), which is a surface of a component B n using multiple measuring ranges / measuring windows M (i x , i y ) and capture in two dimensions.

[0133] Fig. Figure 12 shows a definition and nomenclature of a two-dimensional i x , i y Arrangement of multiple measurement windows M(i x , i y ) of a component B n within the image acquisition method according to the invention.

[0134] Positioning of camera K0 in the probe head 101 in the Z-direction relative to an imaginary measuring plane of the surface of component B n :

[0135] Fig. Figure 13 shows the arrangement of camera K0 in the test head 101 at an intolerable inclination relative to the component B to be tested. n The one through the trapezoid in Fig. 14. The depth of field shown does not fully cover the measurement range / window M(i). x , i y ), since the right corner of the trapezoid defines the measuring range / measuring window M(i x , i y ) not captured within the depth of field Δd.

[0136] The requirement for the alignment of camera K0 in the Z-direction is location-dependent. Generally speaking, it is ensured that the measuring range / measuring window M(i) x , i y ), in the depth of field Δd in space.

[0137] The depth of field Δd is less than 10 mm. According to the invention, the camera K0, and thus the probe 101, is always positioned orthogonally to the measuring area / measuring window M(i). x , i y ) aligned, maintaining a tilt tolerance of + / - 1.5°.

[0138] Fig. Figure 14 shows the arrangement of camera K0 in the test head 101 in a correct orthogonal arrangement with respect to the component B to be tested. n . By aligning the probe head 101 and thus the camera K0 in the z-direction orthogonal to the measuring area / measuring window M(i) x , i y ) ensures that the trapezoid illustrating the depth of field Δd is in Fig. 15 the surface of component Bn in the measuring range or in the measuring window M(i x , i y ) is completely captured within the depth of field. The right corner of the trapezoid is now located in comparison to Fig. 14 in the measuring range / measuring window M(i x , i y ) within the depth of field Δd.

[0139] Fig. Figure 15 shows a diagram to explain the positioning of camera K0 in the test head 101, taking into account the depth of field Δd in relation to a depth of field within component B. n imaginary measuring plane lying within the measuring window M(i) x , i y ).

[0140] In this embodiment, the measuring plane is an x / y plane. It is evident that the shape of component B... n deviates from a flat measurement plane in the x / y plane.

[0141] The camera K0 takes measurements in the measurement area / window M(i x , i y) a rectangular two-dimensional image, as in the two below component B n The horizontal lines are shown with several rectangles.

[0142] In the first row, the rectangles are aligned next to each other, while in the second row, the rectangles are arranged rotated relative to each other.

[0143] It is clarified that camera K0 is used to generate multiple images in relation to component B. n such a way via component B n It is guided and aligned so that the resulting images are not rotated relative to each other. Above the lines in the Fig. Figure 13 indicates several camera positions of camera K0, whose position relative to the surface of component B n according to Fig. 14 in the depth of field range Δd (compare Fig. 14) is carried out so that finally the entire surface of the component B to be tested nThe surface is captured by camera images in the depth of field range Δd, which are also arranged orthogonally to the surface in the z-direction. The probe head 101 of the robot 200 ensures, by means of a corresponding control algorithm, that the images are orthogonal to the surface of component B in the z-direction. n and are aligned with each other in a constant recording direction, in the exemplary embodiment along the direction of travel of the test head 101 along the x-axis. Shape-From-Shading Timing:

[0144] Fig. Figure 16 shows a timing sequence provided according to the invention for the four image acquisitions between two successive measurements or their measurement ranges M1 (n=1) and M2 (n=2) within the image acquisition method by means of the illumination device. Definition and nomenclature:

[0145] The position coordinate of a measurement x, image y = S x,y Example: S1.1 = first measurement range M1 and first image acquisition S2.3 = second measuring range M2 and third image acquisition A distance / length = □S x Time of measurement x, image y = t x,y Example: t1.1 = time of the first image acquisition in the first measurement area M1 t2.3 = Time of the third image acquisition in the second measurement area M3 Time duration = ⊐t x

[0146] In Fig. 16 are two (compare) Fig. 10) Measuring ranges M1 (n=1) and M2 (n=2) with overlap length ΔS U between the two measuring ranges M n (i x , i y ) or between two so-called tiles. The overlap length ΔS U is important so that the multiple measuring ranges M n taking into account the overlap length ΔS U can be arranged next to each other.

[0147] It is essential that the start time of recordings 1 to 4 per measuring range M1 (i) is set by a robot-side master trigger R1 and a robot-side master trigger R2. x , i y ) and M2 (i x , i y The movement is path-synchronous, meaning it depends on the path traveled s of camera K0. Triggers R1 and R2 are not set according to a timer as is usually the case, but rather path-synchronously. This is because the robot 200's probe 101 does not move at a constant speed over component B. n moves. For example, if the robot 200's probe head 101 is in the edge area around component B n As the vehicle moves around, the driving speed decreases. The path-dependent trigger R1 causes the first measuring range M1 (i) to be activated. x , i y ) is recorded. The path-dependent trigger R2 causes the second measurement range M2 (i) to be activated. x , i y) is recorded. With time-controlled triggering, the respective overlap lengths ΔS would be U not constant when the travel speed of the robot's probe 101 changes between two measurement ranges M1 and M2 to be recorded by the camera K0. According to the invention, the overlap lengths ΔS are determined by path-synchronous triggering. U constant. Lighting parameters:

[0148] Fig. Figure 17 shows a definition and nomenclature of the illumination parameters within the image acquisition procedure using the illumination device. Δt B = Exposure time During this period, an image is taken. Δt Lc = Illumination duration with constant luminous flux Within the illumination duration Δt Lc The exposure must be within an exposure time Δt. B lie. In other words: Δt B must lie within the interval. Δt L= Lighting duration. The period of time during which the LED lamp is switched on. Φν N = Nominal luminous flux of the LED lamp Φν NLED = Nominal luminous flux of an LED module The following values ​​are preferred. Δt B = 50 µs Δt Lc = 80 µs Δt L = 100 µs Φν N = 25.0001m / lamp Φν NLED ≈ 4,000 to 50,001 m / LED module

[0149] It is proposed to use LED modules with even higher power outputs that will be available in the future, since further increases in the nominal luminous flux Φν will allow for a greater reduction in power output. NLED a further improvement of the process is achieved with an LED module compared to the LED modules that are currently available with LED lamps with maximum nominal luminous flux Φν N are equipped.

[0150] After switching on the module consisting of lighting elements 101B, a corresponding time (according to the first ramp) is required until the lighting elements 101B reach their nominal luminous flux Φν. N = have reached their constant plateau. After that, the nominal luminous flux Φν remains constant. N constant. After the lighting elements 101B are switched off, the nominal luminous flux Φν drops. N (according to the second ramp) back down to zero.

[0151] A photograph is taken within the exposure time Δt shown. B of the plateau within the illumination period with constant luminous flux Δt Lc , resulting in a constant and therefore predefined nominal luminous flux Φν N for all successive recordings / images according to the embodiment shown in Figures 1 to 4. Trigger concept:

[0152] Fig. Figure 18 shows a representation of a trigger concept for image processing of the images captured by means of the lighting device within the image acquisition procedure.

[0153] Using a graphics card GPU (graphics processing unit).

[0154] Using an integrated circuit FPGA (field programmable gate array).

[0155] The robot 200 generates a master trigger signal R n , especially R1 (compare Fig. 16), as soon as the camera K0, and thus the probe 101, is moved away from the position intended for taking an image.

[0156] The master trigger signal R n triggers a chain of events.

[0157] First, the lighting device is activated using a slave trigger LED according to the first lighting process L n ; L1 of the measuring range M n targeted and started.

[0158] A slave trigger camera (compare) is activated after a short time delay. Fig. 17) according to trigger K n ; K1 controlled and started camera K0, which takes a first image of K1 within the plateau of L1.

[0159] The captured image K1 is transmitted by another trigger of a timing control module, for example via a camera link, to an FPGA frame grabber, with the data transmission corresponding to the time period Δt. K This corresponds to the period Δt. K No further image capture can take place because camera K0 must first transfer the data to the FPGA frame grabber.

[0160] The procedure is repeated image by image K2, K3, K4 according to the previously occurring illumination process L2, L3, L4 within a measuring range M. n . Another measuring range M n This is followed by the next master trigger signal R. n+1 is triggered. Trigger and communication concept:

[0161] Fig. Figure 19 shows a representation of the configuration of a control device for carrying out the procedure for dynamic testing of a component surface, in particular for illustrating the data processing of the trigger and communication concept. Software concept for evaluation:

[0162] Fig. Figure 20 shows a schematic representation of the software concept required for evaluation, in particular the components that are important for data processing for testing in the corresponding cycle times (plant cycle).

[0163] The software concept includes the infrastructure functionalities for the software, in particular for the user interface “GUI”, a Profibus connection “PROFIBUS”, signal processing, in particular inputs and outputs “I / O”, an error handling module for “error handling”, a logger that logs occurring errors “file logger” and a diagnostic module “Diagnostics” that diagnoses and reports errors that nevertheless occur in the components.

[0164] Another component is the FPGA, which organizes image acquisition, shape-from-shading algorithms, filter functions, corrections, the ROI (region of interest), masking, and the creation of local coordinates.

[0165] The GPU uses pre-processed images from the FPGA to detect and classify defects on the component surface. Furthermore, the GPU determines the global coordinate.

[0166] This basic structure is found in the Fig. 21, Fig. 22 to Fig. 23 is shown again in detail. Software concept FPGA functionality:

[0167] Fig. Figure 21 shows a schematic representation of the software concept, in particular the FPGA functions according to the Fig. 19 and Fig. 20.

[0168] Fig. Figure 21 shows the FPGA map and graphically summarizes the individual steps.

[0169] In a first step a) the images are captured using the FPGA K n , K1, K2, K3, K4.

[0170] In a second step b), a shift correction of the pre-planned superimposed measurement ranges M is performed in the FPGA. n , in addition to the pre-planned overlap ΔS explained above U Additionally, unplanned inaccuracies resulting from the robot arm guidance are corrected by adjusting the image captures K n, K1, K2, K3, K4 and the measuring ranges M n The images are "swimmed out relative to each other". The displacement correction cannot be performed directly in the FPGA. For this reason, individual sections of the image captures are used. n K1, K2, K3, K4 are created and transferred to a processor, the CPU, which runs in a loop (compare Fig. 23) calculates the displacement correction, with the result being sent back to the FPGA as correction data for displacement correction (compare arrows in Fig. 21 and Fig. 23) so that the actual shift can be performed in the FPGA.

[0171] In a third step c), the shape-from-shading algorithm is calculated, from which, after the calculation of p and q, the albedo can be derived as a measure of the reflectivity of diffusely reflecting, i.e., non-self-luminous, surfaces.

[0172] In particular, the following can be observed in the various measuring ranges M n The albedo differences are determined.

[0173] In a fourth step d), the result is filtered and corrected using appropriate algorithms.

[0174] In a fifth step e), an analysis of the measurement ranges M takes place. n Regarding ROI “region of interest” and masking, this means that all areas of no interest are cut out, leaving only the areas of interest.

[0175] In a sixth step, the areas of interest are assigned local coordinates, as in Fig. 21 is shown under point f). Thus, the local coordinates are now available at which the corresponding component B is located on its surface. n Relevant surface defects are present.

[0176] This result is sent to the CPU for calculation (compare) Fig. 19) passed on, the further procedure being set out in the Fig. 22 and Fig. 23 is shown. Software concept GPU functionality:

[0177] Fig. Figure 22 shows a schematic representation of the software concept, in particular the GPU functions according to the Fig. 19 and Fig. 20. Defect detection takes place in the GPU, which receives the local coordinates p, q, A from the FPGA.

[0178] In a further step g), defect detection takes place. In other words, potential defects D are identified. n ; D1, D2, D3 identified.

[0179] These potential defects D n D1, D2, D3 are parameterized in step h) according to certain predefined parameters, in particular their size, and classified into defect classes. For example, potential defects D n ; D1, D2, D3 are only classified as true defects if they are larger than, for example, 40 pixels.

[0180] For example, if “real” defects D1 and D3 have been classified in step h), in step i) these defects D1 and D3 are determined from the local coordinates of a measuring area M n the global coordinates on component B n determined as in Fig. 22 under i) is made clear.

[0181] That is, the local coordinates of the defects D1 and D3 in the respective two-dimensional measurement area M n are applied three-dimensionally to the multiple measuring areas M n of component B n "mapped" so that it is clear where the defects D1 and D3 are exactly in three-dimensional space on the component B, which has a three-dimensional freeform shape. n lay.

[0182] The in Fig. 22 three-dimensional bumpers shown under i) as component B nFor example, it has two three-dimensionally defined defects D1 and D3, which are determined two-dimensionally and locally in the measurement-area-wise analysis using the Shape-from-Shading algorithm. Software concept CPU functionality:

[0183] Fig. Figure 23 shows a schematic representation of the software concept, in particular the CPU functions according to the Fig. 19 and Fig. 20.

[0184] The computer's CPU and the computer's GUI are described according to Fig. 23 ensured that in step j) the worker is shown the defects D1 and D3, which have been detected in the GPU, visualized on a monitor.

[0185] In an additional final step k), the results are stored in error tables with appropriate localization, defect type and defect size, and made available for evaluation.

[0186] Finally, further advantages of the invention are mentioned.

[0187] One advantage is that the test system 100 is suitable for various applications, especially for components B. n with matte and glossy surfaces, it is uniform. This eliminates the need for repeated development efforts for different applications, thus minimizing costs overall.

[0188] The Test System 100 and its associated computer programs, especially the software, are standardized and usable for various applications, which also reduces the costs for each individual application. Furthermore, it improves maintenance, spare parts management, and support.

[0189] The fully robot-guided design of the testing system allows for system modifications, including changes to the component type and thus changes to the three-dimensional freeform shape, to require only modifications to the computer programs, particularly the evaluation and robot programming. Testing system 100 can be used unchanged. This results in a high degree of flexibility for testing system 100.

[0190] Furthermore, the test system 100 is dynamic, which includes the continuous movement of camera K0 relative to component B. n or conversely, when recording the measurement range image sequence at a specific variable speed V RIt is understood very quickly. In particular, variable, adjustable test speeds of 1000 mm / s and faster are achieved. This allows larger areas to be inspected in short periods of time. These advantages are of great importance when inspecting surfaces, especially painted car body surfaces, in a continuous cycle. With a typical cycle time of 45 s per component (B n ) can, for example, with the dynamic testing system 100 or the associated testing arrangement and the associated procedure, a component surface of approx. 7.5 m² can be tested in a cycle time of 45 s. 2 be checked.

[0191] Furthermore, as explained, it is possible to investigate robot-guided three-dimensional contour following of freeform surfaces. In other words, surface inspection of curved surfaces is possible, especially dynamic inspection.

[0192] The planned system for 6D position detection of component Bn Even components B can n Components whose position in space is not clearly defined can be inspected. Therefore, precise component positioning is not absolutely necessary.

[0193] The dynamic testing system 100, or rather the associated test setup and procedure, is used for surface testing of painted or unpainted bumpers, in particular the surface testing of painted car bodies in the passenger car and commercial vehicle sectors. Furthermore, the associated test setup and procedure are intended for surface testing of components, especially cylinder crankcase sealing surfaces, camshaft frame sealing surfaces, cylinder head sealing surfaces, flywheels, and brake discs. Surfaces of components from the field of commercially available electrical household appliances, especially kitchen appliances and / or catering equipment, as well as from the telecommunications and consumer electronics sectors, can also be tested. Reference symbol list 100 testing systems 200 robots 201 robot arm SFS Shape-from-Shading T component carrier B component B n nth component 101 Probe K0 Camera 101A Housing part 101B Lighting element 101B-1 Diffuser element 101B-2 Heat sink 101C Electronics 101D Diffuser, light spreader (opaque hemisphere) 101D-1 Viewing aperture 101E Tilt adjustment element 101F carrier plate 101G Light Reflector 102 Stereo Camera System K1 Camera K2 camera t time L n nth illumination process in a measuring range M n Δt b Exposure time Δt B Exposure time Δt L Lighting duration Δt Lc Illumination duration with constant luminous flux Φ ν Luminous flux Φν N Nominal luminous flux LED light-emitting diode Φν NLED Nominal luminous flux of an LED module Δs R Deviation in the position of component B n to a zero position M(i x , i y ) Measurement location, measurement position, measurement window, measurement range (two-dimensional) V R variable speed of the robot arm 201 Δd Depth of field ΔS Bx × ΔS By Image size ΔS Mx ; ΔS My Measuring range size ΔS A ; ΔS A Recording offset ΔS U overlap length Δs R Spacing accuracy x, y, z, α, β, γ Spatial parameters for 6D component localization K n nth image Δt H1 Handling time of the first component B1 Δt H2 Handling time of the first component B2 Δt Pges Total testing duration of one or more components B n Δt P Test duration per component B n Δt M Measurement duration M n Number of measurements within the test period per component B n , n = consecutive nth measurement Δt B Exposure time Δt R Robot (arm) movement duration Δt K Camera data transfer period S x,y Location coordinate of a measurement x, image y ΔS x Route / Length t x,y Time of measurement x, image y Δt x Duration x R1 first trigger R2 second trigger Δt K Reading period of a recording and transmission period R n Master trigger robot D n nth potential defects p, q Albedo

Claims

[1] Probe (101) with a housing part (101A) for optical shape detection and / or surface inspection of a component (B n ) comprehensive - at least one camera (K0) with at least one lens for recording image data of at least one measurement area image of a measurement area image sequence of a component surface of the component (B) n ), - at least one switchable lighting element (101B) as a light source for illuminating at least one area of ​​the component surface of the component (B n ) during the recording of the at least one measurement range image, wherein - the at least one illumination element (101B) outside the north pole of a hemispherical scattering body (101D) opposite a measuring plane (ΔS) Bx x ΔS By ) of the measurement range image is arranged at an angle and - that at least one lens of the camera (K0) is arranged relative to the scattering body (101D) such that the lens of the camera (K0) through the viewing aperture (101D-1) of the scattering body (101D) illuminates the illuminated area of ​​the component surface of the component (B) at its north pole n ) parallel to the measurement plane (ΔS Bx × ΔS By ) of the measurement range image captured, characterized by , that - a diffuser element (101B-1) is assigned to the at least one lighting element (101B), which scatters the light emitted by the at least one lighting element (101B), which then strikes an inner wall of the housing part (101A) at a predefinable angle, wherein - the inner wall of the housing part (101A) is coated to scatter the light, so that the inner wall acts as a light reflector (101G) and as a scattering element, and the scattered light is emitted from the inner wall at a reflection angle, which then points onto a component (B)n ) far-facing surface of the scattering body (101D) hits, - wherein the scattering body (101D) distributes the light passing through it on the exit side of the scattering body (101D), which is directed onto the area of ​​the component surface of the component to be illuminated (B). n ) meets. [2] Probe (101) according to claim 1, characterized by , that the at least one lighting element (101B) is for tilt adjustment relative to the measuring plane (ΔS) Bx × ΔS B ) of the component (B n ) has at least one tilt adjustment element (101E) that is connected indirectly or directly to the housing part (101A). [3] Probe (101) according to claim 1, characterized by , that the diffuser element (101B-1) is arranged on the lighting element (101B). [4] Probe (101) according to claim 1, characterized by, that a special white paint is used as a coating for the scattering and reflecting inner wall, which has a rough surface on its inside with a predefinable surface roughness. [5] Probe (101) according to claim 1, characterized by , that the wall thickness of the hemispherical scattering body (101D) decreases significantly in the lower part - near the equator - towards the upper part - towards the North Pole. [6] Probe (101) according to claim 1, characterized by , that the housing part (101A) is a hollow cylinder. [7] Test setup, characterized by a robot-guided probe head (101) according to at least one of claims 1 to 6 relative to a component arranged for optical shape detection and / or surface inspection (B) n ), wherein the probe (101) is used to record a measurement range image sequence using the camera (K0) in several measurement ranges (M n ) of the component (B n) by moving the camera (K0) relative to the component (B n ) or vice versa is guided by the robot (200). [8] Test setup according to claim 7, characterized by , that the global position of the component (B n ) for 6D component localization in space (x, y, z, α, β, γ) with a system, in particular a stereo camera system (102), is determined and a 6D reference position is calculated, wherein at least one calibration is performed between a robot arm (201) of the robot (200) and the system (102), thereby referencing the component (B n ) in three-dimensional space in its target position relative to the robot-assisted guided probe (101) at a predefinable distance constant between probe (101) and component surface of the component (B n ) is present. [9] Methods for optical shape detection and / or surface inspection of a component (B n) by means of a probe (101) according to claim 1 by the following steps: - Arranging at least one camera (K0), at least one lighting element (101B) and the component (B) n ) in a test setup such that at least one area of ​​a component surface, which comprises at least one measuring range (M n ) corresponds to at least one lighting element (101B) being illuminated, - Recording a measurement range image sequence using the camera (K0) in several measurement ranges (M n ) by a continuous movement of the camera (K0) relative to the component (B) n ) or vice versa, where the measuring ranges (M n ) of the component surface in an image plane of the camera (K) and simultaneously with the recording of the images of the measurement range image sequence with the at least one illumination element (101B) in an associated illumination process (L n ) be illuminated, - Evaluating the recorded images of the measurement range image sequence in at least one of the several measurement ranges (M n ) of the component surface with regard to a changed local surface inclination and / or local optical properties of the component surface. [10] Method according to claim 9, characterized by , that the speed of the continuous relative motion between the camera (K0) and the component (B) n ) during the recording of the multiple images (K n ) is constant for each measurement range image of the measurement range image sequence. [11] Method according to claim 9, characterized by , that the speed of the relative motion between the camera (K0) and the component (B) n ) between the recordings of the multiple images (K n ) is constant or variably changeable for each measurement range image of the measurement range image sequence. [12] Method according to claim 9, characterized by , that the global position of the component (B n) in space in a zero position before recording the measurement range image sequence using the camera (K0) is captured three-dimensionally and stored as the target position. [13] Method according to claim 9, characterized by , that the distance of the component (B n ) relative to the camera (K0) depending on the component size at a predetermined distance from the target position of the component (B) n ) is carried out, whereby the specified distance during the continuous movement is maintained within a predefinable distance accuracy (Δs). R ) is adhered to. [14] Method according to claim 9, characterized by , that for each image of the measurement range image sequence several images (K n ) are recorded, which correspond to at least one measuring range (M n ) representing the measurement range image of the component (B n ) are composed. [15] Method according to claim 14, characterized by , that the recordings of the multiple images (K n) of the measurement range image sequence of the several two-dimensional measurement ranges (M n ) of the captured component surfaces to each other an overlap length (ΔS) U exhibit. [16] Method according to claim 9, characterized by , that each measuring range (M n ) a two-dimensional measurement location M(i x , i y ) is assigned, in whose entire image area with the image size (ΔS Bx × ΔS By ) the measurement plane as a depth of field condition, at most by the depth of field from the component contour of the component (B n ) is deviated from, whereby the camera (K0) is orthogonal to the two-dimensional measurement location M(i) x , i y ) is aligned and a predefinable tolerance of the inclination relative to the measuring plane is maintained with regard to orthogonality. [17] Method according to claim 9, characterized by , that each recording of the multiple images (K n) each image of the measurement range image sequence within an exposure time (Δt) B ) on a plateau with constant luminous flux (Δt Lc ) with a predefined nominal luminous flux (Φν N ) is carried out. [18] Method according to claim 14, characterized by , that the beginning of each first recording of the multiple images (K n ) each image of the measurement range image sequence by a trigger (R n ) path-synchronous, depending on the relative movement of the camera (K0) relative to the component (B) n ) or vice versa, so that the overlap length (ΔS) U ) is constant. [19] Method according to claim 18, characterized by , that a master trigger signal (R n ), as soon as the camera (K0) adjusts itself, depending on the path-synchronous control, to a first recording of the multiple images (K n) of each image of the measurement range image sequence is located at the position provided for, triggers a trigger chain, whereby by means of a slave trigger illumination the at least one illumination element (101B) of the at least one illumination device initiates the associated illumination process (L n ) and, at a time delay, a slave trigger camera of the camera (K0) is controlled and started, using which an image is captured (K n ) within the plateau according to claim 9, after which the next master trigger signal (R) n+1 ) is triggered. [20] Method according to claim 14, characterized by , that - in a first step a) within an integrated circuit (FPGA) the recording of the multiple images (K n ) each image of the measurement range image sequence is taken, and - in a second step b) within the integrated circuit (FPGA) a shift correction of the pre-planned superimposed measurement ranges (Mn ) occurs, whereby in addition to the pre-planned overlap (ΔS U ) additionally, unplanned inaccuracies can be corrected by processing the recordings of the multiple images (K n ) each image of the measurement range image sequence (K n ) and the measuring ranges (M n ) relative to each other are “swimmed out” by a displacement correction after the individual sections of the image capture (K n ) were transferred to a processor (CPU) to calculate a displacement correction, the result being sent back to the integrated circuit (FPGA) as correction data for displacement correction, so that the displacement is performed in the integrated circuit (FPGA), and - in a third step c) the calculation of the albedo (A) as a measure of the reflectivity of the component surface of the component (B) using a shape-from-shading algorithm n ) in which at least one of the several measuring ranges (Mn ) is derived, and - in a fourth step d) the result of the calculation of the shape-from-shading algorithm is filtered and corrected with appropriate filter and correction algorithms, and - in a fifth step e) an analysis of the measurement ranges (M n ) with regard to areas of particular interest (ROI) and masking is carried out, and - in a sixth step f) the areas of interest (ROI) are provided with local coordinates that correspond to those on the component surface of the corresponding component (B n ) relevant surface defects, whereby the local coordinates are passed on to the processor (CPU) for further calculation. [21] Method according to claim 20, characterized by , that - in a seventh step g) defect detection takes place, in which the potential defects (D n ) be identified, and - in an eighth step h) the potential defects (D n ) can be parameterized according to certain predefined parameters, in particular size, and classified into error classes, and - in a ninth step h) of the potential defects (D n ) starting from genuine defects (D n ) are classified, and - in a tenth step i) to these real defects (D n ) from the local coordinates of a measurement area (M n ) the global coordinates according to the global location of the component (B n ) according to claim 12, wherein the local coordinates of the actual defects (D n ) in the respective two-dimensional measuring range (M n ) three-dimensionally across the multiple measuring ranges (M n ) of the component (B n ) are “mapped” so that the actual defects (D n ) exactly in three-dimensional space on the component having a three-dimensional freeform shape (B n) are arranged - in an eleventh step j) the “mapped” real defects (D n ) after being transmitted to a graphics card (GPU), it is visualized and displayed on a monitor, and - in a final twelfth step k) the “mapped” real defects (D n ) are stored in error tables with appropriate localization, defect type and defect size, and made available for further evaluation.

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