EP1846729A1

EP1846729A1 - Coordinate measuring device and method for measuring with a coordinate measuring device

Info

Publication number: EP1846729A1
Application number: EP05819689A
Authority: EP
Inventors: Ralf Christoph; Wolfgang Rauh; Matthias ANDRÄS; Uwe Wachter
Original assignee: Werth Messtechnik GmbH
Current assignee: Werth Messtechnik GmbH
Priority date: 2004-12-16
Filing date: 2005-12-16
Publication date: 2007-10-24
Also published as: EP2284485A3; EP2284480B1; EP2224204A2; EP2224204B1; EP2284480A2; EP2284485B1; EP2284486A3; US20100014099A1; JP2008524565A; WO2006063838A1; EP2284486A2; JP2012137498A; EP2224204A3; EP2284485A2; EP2284480A3; EP2284486B1

Abstract

The invention relates to a method for the measurement of workpiece geometries with a coordinate measuring device (10) and to the device itself. According to the invention, measuring tasks may be optimally carried out without a requirement for devices of differing types, whereby one or more sensors (30), which are of optimal application for the relevant measuring task, are used.

Description

Coordinate measuring machine and method for measuring with a coordinate measuring machine

The invention relates to a coordinate measuring machine for measuring workpiece geometries with movable track axes and one or more sensors for detecting measuring points on the workpiece surfaces. The invention also relates to a method for measuring workpiece geometries with a coordinate measuring machine with movable track axes and one or more sensors for detecting measuring points on the workpiece surfaces.

Coordinate measuring machines are understood to mean measuring devices with one or more mechanically moved axes for measuring geometric properties of workpieces or measuring objects. These coordinate measuring machines are equipped with sensors for recording the geometrical measuring points on the workpiece surfaces. Prior art are predominantly coordinate measuring machines with purely tactile sensors, d. H. the measuring point is generated by touching the workpiece surface with a tactile probe. Also known are coordinate measuring machines with optical sensors, in which the measuring points are determined by an opto-electronic image processing or laser distance sensor. Coordinate measuring machines are also known in which individual ones of these sensors are combined with one another and thus extended possibilities for the user are given.

An overview of the coordinate metrology results from the references DE.Z .: The Library of Technology, Coordinate metrology in industrial use, Verlag Moderne Industrie, Volume 203 (ISBN 3-478-93212-2) and DE.Z .: The Library of Technology, Multisensor Coordinate Metrology, Verlag Moderne Industrie, Volume 248 (ISBN 3-478-93290-4). Again and again, it should be noted that the coordinate measuring device used is not optimally configured for the respective measuring task, so that consequently several devices of different types are necessary.

The present invention is based on the problem, a coordinate measuring machine and a method for measuring workpiece geometries with a coordinate measuring machine such that an optimal configuration for each measurement task is given, so that basically several devices of different types are necessary.

The object is achieved in that a coordinate measuring machine is equipped with all necessary for the solution of the measurement task sensors. These can either be mounted or disassembled or automatically switched on and replaced by appropriate sensor change systems during operation. This allows a flexible measurement of complex workpiece geometries. Of course, it is also possible to have a corresponding number of selected sensors permanently mounted on the device and to measure the workpieces in this configuration.

A coordinate measuring machine is proposed for measuring workpiece geometries with movable track axes and one or more sensors for detecting measuring points on the workpiece surfaces, wherein the sensor is an image processing sensor system and / or a switching touch probe and / or a measuring touch probe, and / or an in the image processing sensor integrated laser distance sensor and / or a separate laser distance sensor and / or a white light interferometer and / or a tactile optical probe, in which the position of the Antastformelementes is determined directly by an image processing sensor, and / or a punctiform intermittent interferometer and / or a punctiform working interferometer sensor with integrated rotation axis and / or a punctiform interferometer sensor with angled viewing direction, and / or an x-ray sensor and / or a chromatic focus sensor and / or a confocal scanning probe are mounted. This is Art or number of used sensors designed for the respective measurement task.

Accordingly, a method for measuring workpiece geometries with a coordinate measuring machine with movable track axes and one or more sensors for detecting measuring points on the workpiece surfaces is characterized in that the sensor is an image processing sensor and / or a switching touch probe and / or a measuring touch probe and / or a laser distance sensor integrated in the image processing sensor system and / or a separate laser distance sensor and / or a white light interferometer and / or a tactile optical sensor, in which the position of the probe element is determined directly by an image processing sensor, and / or a punctiform interferometer sensor and / or a point-shaped working interferometer sensor with integrated rotation axis and / or a punctiform interferometer sensor with angled viewing direction and / or an X-ray sensor system and / or a chromatic focus sensor and / or a confocal Scanning head are used, with type and number of sensors used is aligned to the respective measurement task.

In addition to the basic problem described above, further detail problems arise in the construction of such a coordinate measuring machine. These will be described below and solutions shown.

When using vision sensors in coordinate measuring machines, it is necessary for the user to set different magnifications. This contradicts the demand for cost-optimized optical systems and high imaging qualities, which are difficult to achieve with the otherwise required zoom optics. In a thought independently proceeding the invention this can be solved by selecting the camera of the image processing sensor with a larger resolution (number of pixels) than the resolution of the monitor used or the monitor section used for the image display. Furthermore, the camera can be equipped with random access to certain sections of the overall picture. It is then possible that in the live image or observation image of the coordinate measuring rätes only a section of the overall picture is displayed, which is enlarged to the format of the respective display window or monitor. As a result, the user has the opportunity to select zoomed sections of the image according to his ideas. The magnification between the measurement object and the monitor image can be controlled by changing the selected section of the camera image by the software or the live image can be displayed in the same way. The magnification between the measurement object and the monitor image can be changed by changing the selected section of the camera image. This can optionally be operated by a rotary knob, which is integrated in the control system of the coordinate measuring machine, or via a software controller. It is also possible that when using a high-resolution camera, the image or the image is displayed only in the lower resolution of the monitor, in the background, however, the full resolution of the camera for digital image processing is used to increase the accuracy. The actual optical magnification of the imaging optics of the image processing here is relatively low (typically 1-fold, but at most 5-fold) and the representation of only a section of the high-resolution camera image on the lower-resolution monitor, the optical effect of higher magnification is achieved.

An extension of the procedure described above is that several but at least two cameras are integrated via mirror systems in an optical beam path and use the same imaging objective. In addition, a laser distance sensor can be integrated and also the same imaging lens can be used. It is thus possible to realize different magnifications for the user by choosing different cutting widths or different cameras with different chip size with the same number of pixels or with different number of pixels with the same chip size or both. It is also possible to additionally integrate a laser distance sensor into the beam path, which also uses the same imaging lens via mirror systems. If the magnification ranges given by selection of different camera chips are not sufficient, it is possible to additionally integrate a corresponding after-magnification or redimensioning as an optical component in front of each camera in the camera beam path. In order to avoid that with uniform illumination of the measurement object on the different cameras different illumination intensities occur, which lead to difficulties in the image analysis, are the optical splitters (eg Spie- gel), which divide the beam paths for the different cameras, designed so that all cameras receive the same proportionate light intensity. This is achieved by selecting appropriate reflectance or transmittance of the optical splitters used, in particular splitter levels. In addition, this system can also be extended by an integrated bright field light beam path. This bright-field illumination beam path is likewise realized via a correspondingly dimensioned optical divider such as splitter mirror.

A particular problem is that the selected display resolution is not an integer multiple or integer divisor of the selected image capture resolution. An adaptation in the resolution to each other can be done by re-sampling from the captured with a high-resolution camera image. A corresponding number of pixels required for the resolution of the evaluation or display area is calculated.

Another problem with the use of known coordinate measuring machines is that once generated programs for measuring workpieces subsequently changed or subsequently additional features are to be generated from the measurement results already obtained. This is not possible in the current state of the art because the corresponding associated technology data is no longer available. Autonomously, the problem is solved by the measured with one or more sensors of the coordinate measuring measuring points or video images or X-ray images and their associated position and other technology parameters such as set value of the illumination system used, light intensity, etc. of the coordinate measuring device during the measurement process and stored and be made available for later evaluation. Analogously to this described procedure, it is likewise possible for the image processing sensor to measure a plurality of partial images of a measurement object individually and to form an overall image of the total measurement object or for an overall image of partial areas of the entire measurement area. be joined together. This image can be saved and later evaluated on a separate workstation. For this purpose, the calibration parameters of the coordinate measuring machine used for image recording are also stored and used again in the evaluation software. Offline raster scanning is enabled.

In a modification of the procedure described above, it is likewise possible for the entire measurement sequence including the travel position of the coordinate measuring machine and / or the images of the image processing sensor and / or the images of the X-ray sensor and / or the tactile points of the tactile sensor and / or the scanning points of the laser sensor and / or other technology parameters are stored and thus made available for later evaluation. During the later evaluation, both new measurement results from the existing measurement points and technology parameters can be generated, as well as checked by the measuring device directly on the measuring device as well as the actual measuring programs for the application to further measurement objects can be optimized and changed.

It is provided that when using the image processing sensor in the event that the field of view of the camera is not sufficient to capture the defined by selecting the desired evaluation area (image processing window) area of the measurement object at once, an image is composed of several sub-images and the Users then presented as a measured image and made available for evaluation.

A common problem is that devices should be operated by less trained operators. Here, after the ideal presentation, the measurement objects are simply placed on the coordinate measuring machine and a start button is pressed. The problem is that the coordinate measuring machine must first be shown where the actual measuring object is in order to be able to execute the CNC program in the workpiece coordinates of the coordinate measuring machine. Independently inventive, the following method is proposed for this purpose: After placing the workpiece on the coordinate measuring machine, the measured object is searched for in the measuring range of the coordinate system. Dinatenmessgerätes by driving a sensor, in particular an image processing sensor on a straight, spiral, meandering, circular arc, stochastic or other kind of search path until the existence of a measured object is detected.

In a second method step, a scanning of the outer contour follows, starting at the starting point generated by detecting the measurement object (contour tracking for detecting the outer geometry and position of the measurement object).

In a third method step, the measuring points located within this outer contour are optionally detected by using one of the optionally available sensors of the coordinate measuring machine, for example by scanning with the image processing sensor or by scanning with the tactile sensor. The measuring points thus obtained can then be fed to the further evaluation in accordance with a test plan. It is also possible to subsequently measure rule geometry elements already within the known workpiece position or to use the first measured contour points merely for aligning the workpiece in workpiece coordinates and then to measure rule geometry elements and features such as angles and distances.

Another problem with the use of coordinate measuring machines, in particular those with image processing sensors, is that the different lighting sources have non-linear characteristics, ie the setting of the illumination intensity displayed on the computer software is not associated with a linear relationship with the actual illumination intensity of the lighting system. Among other things, this leads to the fact that different measurement objects can not be measured correctly or programs from one to the other device are not readily transferable. In order to solve the problem, it is suggested that the characteristic curves of the illumination devices of the image processing sensor system of the coordinate measuring machine be recorded, ie the dependence of the illumination intensity on the setting values of the user interface of the measuring device is detected by measuring the intensity to the associated setting value with the image processing sensor system. The corresponding measurement results are displayed as a characteristic in the computer stored on the meter. Alternatively, it is also possible to store these measured values in a so-called light box, which performs the control of the illumination intensity in the operation of the coordinate measuring machine. If one carries out this light characteristic measurement on a calibrated reference object or at least for several devices on a uniform calibration object, this makes it possible to adapt the devices in their behavior to the outside, ie in their behavior with respect to the setting value light - physical illumination value and thus the pro - ensure grammatability of different devices. In order to facilitate the operation of the devices, it is useful to correct the characteristic so that the operator has a linearity, ie that during operation of the coordinate measuring machine, the previously measured characteristic is taken into account for the correction calculation, that apparently a linear characteristic for the operator is present, ie the set value and the illumination intensity then follow a linear relationship. The slope of this linear characteristic can then be adjusted for several devices by a simple correction factor.

Based on the above-described linearization of illumination device characteristics in coordinate measuring machines, it is possible to solve the problem that differently bright measurement objects can not be readily measured with the same illumination setting, since the illumination of the measurement object is not given properly. According to the invention, this is achieved by proceeding according to the following method steps:

When executing automatic programs for measuring parts with different reflection intensity, the set values for the illumination intensities of the different illumination sources specified in the program are set first. In a second step, the illumination intensity, which is influenced by the reflection behavior of the workpiece, is checked with the image processing sensor and it is checked whether the measured value corresponds to the stored nominal value or setting value. If the deviation between the setpoint and the actual value exceeds a fixed limit amount, the setting value of the illumination intensity is linearly corrected and readjusted in accordance with the previously detected light characteristic of the illumination system. Here- results in that the desired Intensϊtätswert, as deposited in the program, is reflected by the measured object. Then the desired object feature is measured. This process is repeated according to the number of image sections that the coordinate measuring device needs to solve the measuring task. The advantage of this approach over conventional light control systems is that only 2 images of the measurement object must be recorded for this control method and thus a very fast light control can be realized.

According to the procedure described above, it is also possible to deposit a plurality of characteristic sets for the coordinate measuring machine, which correspond to the behavior of other similar coordinate measuring machines with, however, different light characteristics. This means that measuring programs from older or third-party manufacturers can also be used.

With coordinate measuring machines, it is possible to scan contours on workpiece surfaces. This can be realized both with a sensor or even with combined operation with several sensors. Is an evaluation of the contours by comparison with target contours of z. As CAD files, it is necessary to set the target and actual computers internally on top of each other to realize a graphical comparison. In particular, in flexible or flexible parts, this is not possible by simply moving the relative position or rotation of the relative position, since the parts are elastically deformed. By proceeding according to the own inventive content method described as follows, this problem is solved. The Best-fitting between the target and actual contour in addition to the Relativlageveränderung between nominal and actual contour itself and the length of contour sections corresponding to the desired length while maintaining the curvature or alternatively the contour curvature while maintaining the Konrurlänge on Actual contour changed so that an optimal coverage is achieved with the target contour. If parts with excellent geometric features are difficult to check by elasticity or deformation, this process can be assisted by fitting the actual and target contours to a group of actual and target contours on individually distinguished features, such as contours or contours Circular structures or other recurring structures takes place and so a distortion of the actual contour for optimum coverage with the target contour is generated. In an analogous manner, this is possible in the case of cylindrical parts, in which the contours measured on the cylinder surface are partially twisted or screwed onto the cylinder jacket surface, in order to produce an optimum overlap between the desired and the actual contour. This procedure is particularly suitable for measuring standard stents in medicine. The method described above is also possible in analogous reverse procedure, ie adjustment of the target to the actual geometry.

In order to achieve a metrologically meaningful evaluation with target / actual comparison, it makes sense to optimize the adaptation not to a minimization of the deviation between the actual and actual contour, but rather to a minimization of the tolerance zone utilization. In practice, however, the tolerances for the measurement of the parts are generally given as dimensional, geometrical and / or positional tolerances in the form of printed drawings or CAD drawings. The implementation of these tolerances in corresponding tolerance zones can be solved by the coordinate measuring machine. This problem is self-inventively solved in that the coordinate measuring machine algorithms are deposited, which realize an automatic conversion of the dimensional, shape and / or position tolerances on contour section related tolerance zones. For the simple case, a uniform overall tolerance for the contour section results here for several tolerances. With more complicated tolerances, however, it is also possible that this is not feasible. In this case, the coordinate measuring machine automatically performs a multiple evaluation for the different tolerance situations. For this purpose, each setpoint or actual contour segment is assigned several tolerance zones. Then, an evaluation of a plurality of target or actual contour regions combined into groups and / or a complete workpiece of target and actual contours for each of a plurality of different positional, dimensional and / or shape tolerance situations is performed automatically one after the other. Optionally, at the end of the evaluation, the most unfavorable result of the various target / actual comparisons for each desired or actual contour segment can be displayed with the aid of the different tolerance zones. When using image processing with autofocus sensors, there is often the problem that partially transparent layers are to be measured in their height extent. In order to solve the problem, it is inventively suggested that autofocus measurement points be generated on several semi-transparent layers simultaneously with the image processing sensor in autofocus mode for a plurality of evaluation regions. This is achieved by moving the image processing sensor in the measuring direction and simultaneously recording several images. The focus measuring points are calculated in the respectively determined evaluation ranges according to a contrast criterion.

When using coordinate measuring machines in conjunction with a laser distance sensor, it is common to scan contours on workpiece surfaces in the sensor measuring direction, d. H. In one direction, different from the sensor measuring direction, the coordinate measuring device is moved on a predetermined path. Controlled by the sensor, the coordinate measuring machine is tracked in the remaining axis in the measuring direction of the sensor. In practice, moreover, the task z. B. to measure a cone in predefined contour lines. This is not possible with the procedure described above. It is self-inventively provided to solve the problem that the position control of the sensor or the position control loop of the coordinate measuring machine in dependence on the deflection display of the laser distance sensor is controlled so that the deflection of the laser distance sensor remains constant. Here, the axes of the coordinate measuring machine are moved perpendicular or nearly perpendicular to the measuring direction of the laser distance sensor. According to the boundary condition, it is considered that the measuring points of the laser distance sensor lie in a predefined cutting plane. It is thus possible to scan contour lines on the measurement object. The laser distance sensor is moved on a path on which the distance between sensor and object is the same.

Another problem with the use of coordinate measuring machines is that the measuring objects have to be measured from different sides. However, if the position of the measuring object in the coordinate measuring machine is changed, the reference of the measuring points is lost to one another and a common evaluation of the measuring points is no longer possible. Self-inventively, this problem is solved by either Reference features of the measurement object itself or additionally attached reference features (preferably balls) are attached directly to the measurement object or on a measurement object receiving frame. The procedure for measuring with the coordinate measuring device is then as follows:

1. Measuring the position of one or more, preferably three reference marks, in particular balls on the measurement object or this stationarily assigned;

2. Save the position in the computer of the coordinate measuring machine;

3. measuring any points accessible by one or more sensors on the measurement object;

4. Change in the position of the measurement object in the measuring volume of the coordinate measuring machine by hand or an integrated rotary axis or rotary pivot axis;

5. Re-measuring the reference marks;

6. Internal comparison of the respective reference marks so that there is a minimized shift between these software-internally;

7. Measuring further points on the measurement object with one or more sensors of the coordinate measuring machine;

8. repetition of the above processes in any number;

9. Joint evaluation of all measuring points of the measuring object during the measuring cycle described above in a coordinate system.

The advantage with this procedure is that the accuracy of the rotary swivel axis used for the rotation or pivoting of the test object is not included in the measurement result. Of course, the position measured values of the rotary axis or rotary swivel axis can additionally be used for the evaluation. It is also possible to measure the reference marks (preferably balls) with one sensor and to carry out the measurement on the workpiece with one according to another.

Coordinate measuring machines with various sensors also have, among other things, optionally sensors with an opto-tactile button. The determination of the Position of the sensing element (sphere, cylinder) by an image processing sensor (WO-A-98/157121). One problem is to adjust this sensor to the position of the probe ball. Self-inventively, this is realized by additionally arranging an adjusting unit on the coordinate axis bearing the sensor, which permits a relative adjustment between the sensing element (probe ball including stylus and holder) and the image processing sensor. For example, via an autofocus method is then an automatic focus of the Antastformelementes in relation to the image processing sensor possible.

If highly accurate measurements are performed with tactile sensors, the problem may exist that the geometric quality of the sensing element (sphere, cylinder or similar) is worse than the required measurement uncertainty. This leads to unusable measurement results. In order to solve this problem, it is inventively suggested that the geometry of the probing element (eg ball, cylinder) is measured in advance on an external measuring station and these measured values are automatically taken into account as correction values when using the probing element in the coordinate measuring machine. Alternatively, it is possible to detect the deviation of the actual geometry from the ideal target geometry of the probe element by measurements in the coordinate measuring machine used on a highly accurate calibrated normal (such as calibration ball) itself.

An important option for coordinate measuring machines is the possibility of exchanging various sensors or stylus adapters and the like. Ä. For this purpose, a change device can be provided according to the invention. In order not to limit the measuring volume of the coordinate measuring machine by placement of the changing device, it is inventively provided to arrange this changing device on a separate adjustment axis, which moves the changing device out of the measuring volume, if no change operation takes place, and enters the measuring volume, if a change operation is provided. This adjustment axis can be performed with a spindle drive. Alternatively, it is possible to work only with 2 stops, which are positioned against by a motor drive. Alternatively it is possible to determine the 2 positions by means of a linear displacement encoder or a rotary encoder on the spindle drive.

Coordinate measuring machines are generally exposed to different operating temperatures at the place of use. If several sensors are attached to the coordinate measuring machine, this will cause the positions between the different sensors to change thermally. This leads to measurement errors. In order to solve this problem, it is inventively suggested that the temperature of the mechanical assemblies which serve to secure the various sensors be measured at one or more locations and the expansion of the corresponding mechanical components to compensate for error effects caused by temperature fluctuations at the installation site of the coordinate measuring machine the calculation of the measuring points detected by the different sensors. This means that z. Example, when using a button in an image sensor, the temperature of the device connecting both sensors permanently measured, linked to the linear expansion coefficient of the material used for this component and so the corrected relative position of the sensor is calculated in the coordinate system of the coordinate measuring machine. These corrected values are included in each measurement of measurement points. In a typical embodiment, the temperature compensation described above is accomplished by linearly multiplying the measurements by a constant factor that is affected by the temperature.

In order to be able to measure a measurement object on a coordinate measuring machine from several sides while measuring on a coordinate measuring machine, it makes sense that the measurement object can be clamped in an axis of rotation and thus screwed into an optimum position for the measurement with the various sensors. In addition to this, it is possible to record the measurement object in addition to the rotation axis itself with a correspondingly arranged counter-tip. When clamping measuring objects between points, however, the problem arises that the clamping force of the counter-tip can lead to deformations of the measured object. In order to exclude errors caused by this, it is inventively suggested that the object to be measured is constantly deformed or that the counter-tip is automatically positioned against the measured object until a predefined force is reached. Here, the counter-tip is resiliently mounted, so that via a deflection and a corresponding limit switch the corresponding required force can be determined.

Another problem with the use of coordinate measuring machines is that often several contours are to be measured close to each other. This often leads to considerably longer measurement times for the required number. This problem is inherently solved by arranging a plurality of tactile sensors of similar or different construction close together on a common mechanical axis of the coordinate measuring device. It is also possible to arrange a plurality of said sensors on a rotary pivot unit. With these tactile sensors arranged in this way, contours can simultaneously be recorded on workpiece surfaces in the scanning mode. There is thus a two-dimensional measurement. According to the invention, an embodiment variant results that only one of the plurality of arranged buttons is used for realizing the scanning operation of the coordinate measuring machine (regulation of the positioning process of the coordinate measuring machine depending on the deflection of the probe) and the other buttons are only used for acquiring measured values (passive). operate. These do not contribute to the regulation of the coordinate measuring machine. The control of an optional rotary swivel unit for the multi-key arrangement can be automatically controlled by the difference between the average deflections of the various individual keys. Typical application for said multiple probe arrangement is the measurement of tooth flanks, of gears or the measurement of the shape of cam of camshafts. According to the invention, a plurality of measuring tracks are generated simultaneously during a measuring process.

When measuring with an image processing sensor on outer edges of workpieces, in particular of rotationally symmetrical cutting tools or inserts, there is the problem that the image processing sensor is permanently nachzufokussieren on the outer edge to be measured. Self-inventively, this problem can be solved by additionally integrating a laser distance sensor in the image processing beam path. The laser sensor measures the distance of the image processing sensor to the workpiece surface in the vicinity of the outer edge to be measured and is connected to a position control loop of the coordinate measuring machine in such a way that an automatic detection management takes place. The image processing sensor is thus permanently focused. The tracking of the workpiece for focusing can be realized alternatively with the Cartesian axes of the coordinate measuring machine or by an optional rotation axis (rotation of the workpiece to be measured).

When using image processing sensors in coordinate measuring machines, there is a problem in that the number of evaluated images does not meet the required number of measurement points or the total measurement time can not be realized sufficiently to meet the requirements. In the prior art, the camera of the image processing system of the coordinate measuring machine in video standard (50 or 60 Hz) operated and stored in a loose order given by the operator or by the sequence program of the coordinate measuring machine, an image and evaluated. As a result, the number of evaluated images is significantly smaller than the number taken by the camera. As a result, the measuring time is not optimal or the measuring point number is insufficient. To solve the problem, it is inventively suggested that the evaluation of the image is performed for each image taken by the camera. This means that the evaluation is realized in video real time. Ie. During the time in which the image is taken by the camera of the image processing system, the calculation of the image analysis on the previous image takes place in parallel in the background. This process is repeated continuously until the end of the entire measuring process. Thus, the image evaluation of the image processing sensor in video real-time, i. H. in the same frequency as the refresh rate of the camera. On the basis of this procedure, it is possible that the measurement object is rotated during the measurement with an axis of rotation and recorded and evaluated with the frequency of the camera measurement points on the outer edge of the measurement object for realizing a roundness measurement in video real time.

Self-inventively, it is also possible that to improve the signal to noise ratio of image processing sensors or X-ray sensors, the integration time is extended until there is a sufficiently low signal to noise ratio. This means that several successive images are added and then the image evaluation takes place on this added image. This process can automatically be The integration time of such a camera is extended until a sufficiently good image can be stored and further processed. The intensity of the pixels of the image is monitored up to a setpoint and increased by storing several images.

In coordinate measuring machines according to the invention, image processing sensors with laser sensors integrated in the beam path can be used. These beam paths can also be designed as zoom optics. In a further embodiment, the working distance of the zoom optics used is adjustable. In practically used systems, it is to be expected that the desired optical properties for the integrated laser distance sensor and the image processing sensor will not be present at the same setting parameters (working distance / magnification). Self-inventively, the aperture and working distance of the zoom optical system used can alternatively be optimized for the laser sensor or the image processing sensor by an additionally exchangeable attachment optics. This additional optical system can be designed so that the same setting parameters (working distance / magnification) are not present for the laser sensor and the image processing sensor. By additionally exchangeable attachment optics, the aperture and working distance of the zoom optical system used can be optimized alternatively for the laser sensor or the image processing sensor. This additional optical system can be designed so that it creates optimized conditions for the laser sensor. It is possible to connect this attachment to the zoom optics via a magnetic interface and / or to switch it on or off via a probe changing station which is otherwise used for tactile sensors.

When measuring with image processing sensors in coordinate measuring machines different illumination sources, such as bright field, dark field, transmitted light, are used to achieve optimal contrast ratios for parts of a workpiece to be measured. These illumination sources are varied with regard to their setting, such as intensity, solid angle of the illumination (illumination angle or direction of the illumination), direction of illumination, in order to achieve optimal conditions. These parameters are different for sections of the object to be measured, which is why it is not possible with a lighting setting the entire object optimal image. In order to avoid this disadvantage, it is inventively suggested that, to generate an optimum contrasted image, several images are taken successively with different illumination sources and the areas with optimum contrast are taken from each image and combined to form a geometrically correct overall image. In detail, it is thus possible for different images of the same object or object detail to be recorded by using different illumination directions of dark field illumination and / or different illumination angles of dark field illumination and / or use of bright field illumination, and to combine the contrast-optimal regions of the individual image into an optimized overall image. This can then be subsequently evaluated metrologically. The described procedure can likewise be applied to each individual pixel of the image processing sensor, ie for each pixel of the resulting overall image the pixel with optimum contrast is selected out of the number of individual images. The contrast of a single pixel is determined by the amplitude difference of that pixel to its neighbors in the image.

If the surface contour of workpieces is measured with an autofocus sensor, the measuring points are usually specified by the operator in the teach-in mode. If unknown contours are to be measured in this method, this is only possible with difficulty. This is inventively improved by the fact that with an autofocus sensor, a scanning process on the material surface is performed by theoretically calculated from the already measured focus points by extrapolation, the probable location of the next measurement point and accurately measured by a new autofocus point. If this process is repeated several times in succession, this results in a fully automatic scanning. In this case, both the number of points to be scanned along a line and an area to be scanned on the workpiece or measured object can be specified by the operator. The extrapolation of the next measurement point from the two or more preceding measurement points can be done by a linear extrapolation. Furthermore, it is also possible to perform this extrapolation by polynomial interpolation from the last measured 2 or more points. If several delimited areas of the image are used to determine focus measurement points during each focus operation, a sequence of measurement points during a focus process can be generated in this way. If such sequences are put together, a scan of complete contours is also realized.

When using image processing sensors or X-ray tomography sensors, the problem arises that, depending on the properties of the measurement object within an image, there are regions with both strong and weak intensities. This is caused by the different reflection or transmission properties of the materials. As a result, only small signals are present for the "dark" image areas resulting in a poor signal-to-noise ratio, however, a stronger illumination or irradiation of the object would lead to overshoot in the bright areas and thus exclude.

Self-inventively, the described problem is solved in that for each image section several images are recorded with different illumination intensities. Subsequently, these images of the same object area are merged into a new overall image such that the pixel amplitudes are normalized to the respective illumination intensity that was used. For the overall image composition, the pixels from the respective image that are within the permitted dynamic range (eg 0-245 at 8 bits) are then used. Overshoot amplitudes are not taken into account in the respective picture. For pixels with several valid pixel amplitudes, an averaging is performed from the values. Subsequently, the overall picture can be evaluated.

Both with the use of image processing sensors and in X-ray tomography applications, the radiation intensity or irradiation intensity of the test object is often insufficient to allow optimum measurement. This can be inventively improved by the fact that for quality optimization of recorded images in image processing sensors or X-ray tomography sensors taken multiple images of an object area, each with different illumination or radiation intensities and then joined together to form an overall picture become. For example, the individual image sets taken from each individual image with a different illumination or radiation intensity, the pixel amplitudes (pixels used), which lie within a valid amplitude range (typically between 0 and 245 LSB). Pixel amplitudes with amplitude evaluation that indicate an overshoot (eg> 245 LSB) are ignored during the evaluation. If valid pixel amplitudes from a plurality of images are present relative to a pixel, an average value can be formed from the normalized pixel amplitudes. It is possible to perform all described calculations on amplitude values normalized to the radiation or illumination intensity used.

Further details, advantages and features of the invention will become apparent not only from the claims, the features to be taken for themselves and / or in combination, but also from the following description of the drawing to be taken preferred embodiments.

Show it:

1 is a schematic diagram of a coordinate measuring machine,

2 is a detail of a coordinate measuring machine in a schematic representation,

3 is a schematic diagram of a coordinate measuring machine with Bildverarbei- tion and laser distance sensor,

4 is a schematic diagram of a measuring method,

5 shows a further basic illustration of a measuring method,

6 is a schematic representation of a contour tracing,

7 light intensity curves, 8 shows a desired and an actual light intensity curve,

FIG. 9 setpoint and actual comparison of contour data, FIG.

10a, 10b target and actual contours,

11, 12 a measuring object with tolerance zones,

13 shows an arrangement for measuring semitransparent layers,

14 shows a measuring arrangement for measuring a height profile,

15 shows a measuring arrangement for measuring a measurement object in different positions,

16 shows an arrangement for determining the position of a probing element,

17 shows an arrangement with two interconnected sensors,

18 shows a clamping arrangement for a measuring object,

FIG. 19 shows a sensor rake for measuring a plurality of measuring paths, FIG.

20 shows an arrangement for measuring a tool,

21 shows a measuring arrangement with image processing sensor and laser distance sensor,

Fig. 22 is a schematic diagram for measuring determined by extrapolation measuring points and 23 is a schematic diagram of an arrangement with an X-ray tomography sensor.

The invention or invention complexes are explained in more detail below in preferred exemplary embodiments.

The corresponding excitations take place against the background that knowledge of coordinate metrology is present. In addition, the references DE.Z .: The Library of Technology, Coordinate Metrology in Industrial Use, Verlag Moderne Industrie, Volume 203 (ISBN 3-478-93212-2) and DE.Z .: The Library of Technology, Multisensor Coordinate Metrology , Verlag Moderne Industrie, Volume 248 (ISBN 3-478-93290-4) referenced, which is incorporated herein by reference and whose contents belong to the disclosure of the description.

In Fig. 1, a coordinate measuring machine 10 is shown purely in principle, which is equipped with the required for the respective solution of a measurement task sensor or the required sensors. The sensors can either be mounted or disassembled or can be automatically switched on and off during operation by means of corresponding sensor change systems. As a result, a flexible measurement of complex workpiece geometries is possible. Of course, the invention will not be abandoned if a corresponding number of selected sensors are permanently mounted on the device to measure objects in this configuration.

The well-known and again reproduced in Fig. 1 principle of a coordinate measuring machine 10 comprises a z. B. granite base frame 12 with measuring table 14, on which an object to be measured 16 is positioned to measure its surface properties.

Along the base frame 12, a portal 18 is adjustable in the Y direction. For this purpose, columns or uprights 20, 22 are slidably supported on the base frame 12. From the columns 20, 22 a traverse 24 goes out, along which a carriage is movable, which in turn receives a quill or column 26 which is adjustable in the Z direction. From the quill 26 or, if necessary, a changeover interface 28 connected to the sleeve 26, a sensor 30 is designed which, in the exemplary embodiment, is designed as a tactile sensor, which measures tactile-optically when the sleeve 26 contains an image processing sensor. In that regard, however, reference is made to well-known techniques, as well as with respect to other used sensors such as laser distance sensor, white light interferometer, image processing sensors, X-ray sensor or chromatic focus sensor or confocal scanning probe, without thereby limiting the teaching of the invention. The sensor or sensors are selected and used in accordance with the measuring task in order to optimally configure the coordinate measuring machine 10 for the respective measuring task. At the same time, problems that occur with conventional coordinate measuring machines are solved.

In order to be able to use the coordinate measuring machine 10 with the suitable sensor, the coordinate measuring machine can have a sensor changer, as can be seen in principle from FIG. 2. Thus, a plurality of sensors can each optionally be provided with the coordinate measuring machine via an exchange interface and exchanged by hand or by automatic retrieval of the coordinate measuring machine at a parking station.

FIG. 2 shows a section of a coordinate measuring machine with a quill 32 in plan view. The sensors connectable to the quill are identified by the reference numerals 34, 36, 38. In this case, the sensors 34, 36, 38 may be designed optically or tactile, to name only sensor types. The coordinate measuring machine, ie the quill 32, is adjustable in the YXZ direction in order to carry out an exchange of the sensors 34, 36, 38. In the exemplary embodiment, the sleeve 32 and thus the coordinate measuring device positioned on a positioning path 40, the sensor 34 in a parking station 42 and is then able to record one of the parked in the parking station 42 sensors 36, 38 and attach again to the sleeve 32. The parking station 42 or the Tasterwechslersystem can be adjusted by an adjustment axis 44 so that the probe changer 42 is arranged in non-operation outside the measuring volume of the coordinate measuring machine. When using image processing sensors in coordinate measuring machines, it is necessary for the user to set different magnifications. This contradicts the demand for cost-optimized optical systems and high imaging qualities, which are difficult to achieve with the otherwise required zoom optics. In order to meet these requirements, it is provided that the camera of the image processing sensor is selected with a larger resolution (number of pixels) than the resolution of the monitor used or of the monitor section used for the image display. Furthermore, the camera can be equipped with random access to certain sections of the overall picture. It is then possible that in the live image or observation image of the coordinate measuring machine only a section of the overall image is displayed, which is enlarged to the format of the respective display window or monitor. As a result, the user has the option to select zoomed sections of the image according to his ideas. The magnification between the measurement object and the monitor image can be controlled by changing the selected section of the camera image by the software or the live image can be displayed in the same way. The magnification between the measurement object and the monitor image can be changed by changing the selected section of the camera image. This can optionally be operated by a rotary knob, which is integrated in the control system of the coordinate measuring machine, or via a software controller. It is also possible that when using a high-resolution camera, the image or the image is displayed only in the lower resolution of the monitor, in the background, however, the full resolution of the camera for digital image processing is used to increase the accuracy. The actual optical magnification of the imaging optics of the image processing here is relatively low (typically 1-fold, but at most 5-fold) and the representation of only a section of the high-resolution camera image on the lower-resolution monitor, the optical effect of higher magnification is achieved.

The method explained above is to be explained in principle with reference to FIG. FIG. 3 shows a section of a coordinate measuring machine. Thus, the object to be measured 16 is shown on the measuring table 12. Above the measuring object 16, an imaging lens 46 and a camera such as CCD camera 48 are arranged, the is connected via a computer 50 to a monitor 52. The hardware of the computer 50 or computer, it is possible to adjust the resolution between the camera 48 and the monitor 52 computationally, for. B. to use a larger camera resolution than can be reproduced by the monitor 52. Likewise, it is possible to access with random access to certain sections of the overall picture or zoom the live or observation image of the coordinate measuring only as a section of the overall picture on the format of the display window enlarged. By selecting different sections of the captured camera image for display on the monitor 52, a different effective magnification of the total beam path is achieved for the viewer. This magnification can be adapted to the requirements of the application by changing the section. By z. As an electronic encoder connected to the computer 50 54 this is ergonomically operated. It can further be realized that the actual image evaluation in the computer 50 takes place with the full resolution of the captured camera image by the camera 48. As a typical magnification for the measuring objective 46 in this case is a simple, but at most 5 times magnification in question. A higher optical magnification is realized by the previously described resolution adjustment. By an additional arrangement of a mirror 56 and a further camera 58, it is possible to vary the triggering range even more. Switching also takes place via the computer 50. In this case, both cameras with different chip sizes can be used with the same number of pixels as well as with different pixel numbers with the same chip size or both combined. In addition, a laser distance sensor 60 may use the same optical path.

In the exemplary embodiment, the camera 58 is equipped with additional post-magnification optics 62 to define the magnification. The optical splitters or mirrors used in the beam path, which are identified by the reference numerals 56 and 64 in FIG. 3, are designed such that after the division all affected cameras 48, 58 or sensors 60 are provided with the same light intensity. Via an additional optical divider 66 and a lighting device 68, an integrated bright field incident light is realized. In addition to the described procedure, an even higher level of re-sampling from the respectively acquired camera image her resolved camera image with the purpose of representing an even higher magnification. In each case, additional pixels are determined by interpolation between real measured pixels.

A problem with known coordinate measuring machines is that once created programs for measuring workpieces are subsequently changed or subsequently additional features are to be generated from the measurement results already obtained. This is not possible in the current state of the art because the corresponding associated technology data is no longer available. According to the invention, it is provided for solving the problem that the measurement points or video images or X-ray images measured with one or more sensors of the coordinate measuring machine and their associated position and other technology parameters such as set value of the illumination system used, light intensity or magnification of the lens used during the coordinate measuring machine Recorded recorded the measurement process and made available for later evaluation so. Analogously to this described procedure, it is also possible that with the image processing sensor a plurality of partial images of a measurement object are individually measured and combined to form an overall image of the overall measurement object or to an overall image of partial regions of the entire measurement object. This image can be saved and later evaluated on a separate workstation. For this purpose, the calibration parameters of the coordinate measuring machine used for image recording are also stored and used again in the evaluation of the software. This will be explained in principle with reference to FIG. 4.

A measuring object 68 is to be measured with an image processing sensor. With the reference numerals 70, 72, 76, 78 image sections are shown, which are detected at different positions in the X, Y coordinate system 80 of the coordinate measuring machine on the measuring object 68. In addition to the actual X and Y positions, the image contents of the object sections captured at the respective positions are stored, in addition to the respectively associated image processing evaluation windows 82, 84, 86, 88 and the parameters stored thereon in the coordinate measuring machine such as magnification of the objective used, setting value of the used lighting system. After Taking all of these values, the actual measurement of the image contents and the link, eg. As the measurement of an angle 90 or a distance 92, take place.

If, when using an image processing sensor, the field of view of the camera is not sufficient to detect the area of the measurement object defined by selecting the desired evaluation area (image processing window) at once, it is provided that an image is automatically composed of several parts which are automatically combined Users then presented as a measured image and made available for evaluation. This is illustrated in principle with reference to FIG. 5. A feature in the form of a bore 96 is to be measured on a measurement object 94. The field of view 98 of an image processing sensor is insufficient to fully capture this feature. The operator sets an evaluation area 100 that is significantly larger than the visual field 98. The software automatically recognizes this and, in the exemplary embodiment, defines four positions 102, 104, 106, 108, which are measured successively in order to combine an overall image and to metrologically record the feature to be measured, ie the bore 96 in the exemplary embodiment.

By means of FIG. 6, the following method steps are to be illustrated when measuring with an image processing sensor system, which are carried out in succession:

Searching the measuring object in the measuring range of the coordinate measuring machine by driving a sensor on a straight, spiral, meandering, circular arc or stochastic or other kind Such search path until the existence of a measuring object is detected, and

Start a scanning of the outer contour of the measurement object (contour tracking to capture the geometry and position of the outer contour of the DUT).

Furthermore, optionally located in the interior of the outer contour measuring points on the measurement object can be detected by screening with an image processing sensor and / or scanning with other sensors. For example, a measurement object 110 lies on the measurement table 12. An image processing sensor used for the measurement has an evaluation region 112. By moving on a z. B. spiral track 114, the basic position of the measuring object 110 is detected on the measuring table 12 by changing the image content. At the point of impact of the image processing sensor with the object contour (area 116), an outer contour scanning of the measurement object 110 begins until complete detection of the outer contour along the path 118 (contour tracking). Thereafter, in order to completely detect the total measurement object, a grid-shaped detection of the inner area of the measurement object 110 in the previously defined outer boundaries 120 is automatically carried out, so that subsequently the total measurement object 118 is available for evaluation.

A problem with the use of coordinate measuring machines with image processing sensors is that the different lighting systems have non-linear characteristics. This leads u. a. In addition, different measurement objects can not be measured correctly or programs from one to the other device can not be easily transmitted. To solve this problem, the invention proposes that the characteristics of the illumination devices of the image processing sensor system of the coordinate measuring machine are recorded, d. H. the dependence of the illumination intensity on the adjustment image of the user interface of the measuring device is detected by measuring the intensity for the associated setting value with the image processing sensor system. Corresponding measurement results are stored as a characteristic curve in the computer of the measuring device. It is also possible to store the measured values in a so-called light box, which controls the illumination intensity during operation of the coordinate measuring machine. If one carries out this light characteristic measurement on a calibrated reference object or at least for several devices on a uniform calibration object, the possibility is opened up of the devices in their behavior towards the outside, ie. H. to compensate in their behavior with respect to the setting value light - physical illumination value and thus to ensure the program portability of different devices.

In order to facilitate the operation of the devices, it is useful to correct the characteristic in such a way that the operator has a linearity, ie that in the operation of the device Ordinatenmessgeräts the previously measured characteristic curve is taken into account for the correction calculation that apparently has a linear characteristic for the operator. Then, the set values and the illumination intensity are linearly related to each other. The increase of this linear characteristic can then be compensated for several devices by a simple correction factor.

Thus, an original light characteristic 122 of an illumination system for an optical coordinate measuring machine is shown in FIG. 7 at the top left. The illumination intensity E does not depend linearly on the current flow I through the illumination source. In the graph of FIG. 7 at the top right, a similar, but in detail different characteristic 122 of a second coordinate measuring machine is shown. By detecting the dependence of the illumination intensity E on the current flow I at interpolation points 124 and 126 of the respective characteristic curve 120 and 122 and storing this interpolation point information in a control computer for the illumination setting, these are corrected by dividing the default value for setting the current I such that gives a same linear characteristic for both instruments. These are shown in the lower representations of FIG. 7 and identified by the reference numerals 128, 130. As a result, the same illumination intensities are achieved with a default value.

Fig. 8 shows the procedure for controlling the light intensity E. When creating a CNC program for measuring with z. B. image processing sensor is in the teach-in by the combination of coordinate measuring machine with measurement object in z. B. incident light, a light characteristic 132 is effective. The setpoint value of the illumination intensity E _s is set by the illumination current I ₁ . If another measurement object or a different location of the measurement object is now measured, the reflection properties of the material may have changed, which leads to a change in the increase in the light characteristic. This second light characteristic 133 is likewise shown in FIG. 8. If the illumination intensity is then measured after setting the current Ij, the illuminance Ei is determined as the result. This does not correspond to the setpoint E _s . Since Ij and Ei the increase of the now currently valid light characteristic is known, the necessary current I _{s can be} calculated in a simple manner to set the target list strength E _s . The physical structure for the above-described process is shown in FIG. 2, in which the light source 68, the mirror 66 and the objective 46 represent the illumination device. The calculation takes place via the computer 50. The reflection behavior of the measurement object 16 is different within the measurement objects and generates the different response to current I and illumination intensity E.

With coordinate measuring machines, it is possible to scan contours on workpiece surfaces. This can be realized both with a sensor or even with combined operation with several sensors. Is an evaluation of the contours by comparison with target contours of z. As CAD files, it is necessary to set the target and actual computers internally on top of each other to realize a graphical comparison. In particular, in flexible or flexible parts, this is not possible by simply moving the relative position or rotation of the relative position, since the parts are elastically deformed. By proceeding according to the own inventive content method described as follows, this problem is solved. In addition to the relative position change between the nominal and actual contour, the length of contour sections corresponding to the nominal length while retaining the curvature or, alternatively, the contour curvature while retaining the contour length on the profile will be inherent in the best fit between nominal and actual contour Actual contour changed so that an optimal coverage is achieved with the target contour. If parts with excellent geometric features are difficult to check by elasticity or deformation, this process can be assisted by fitting the actual and target contours to a group of actual and target contours on individually distinguished features, such as contours or contours Circular structures or other recurring structures takes place and thus a distortion of the actual contour for optimum coverage with the desired contour is generated. In an analogous manner, this is possible in the case of cylindrical parts, in which the contours measured on the cylinder surface are partially twisted or screwed onto the cylinder jacket surface, in order to produce an optimum overlap between the desired and the actual contour. This procedure is particularly suitable for measuring standard stents in medicine. The method described above is also in analogous reverse procedure, ie adaptation of the target to the actual geometry possible.

9 is to illustrate in principle that the actual contour is partially rotated or screwed for optimal coverage with the desired contour in a cylinder-shell surface. Reference numeral 134 represents a point cloud, which is essentially represented by a cylindrical lateral surface. Due to the distortion of the measuring object, the structures on this cylindrical lateral surface are twisted or twisted relative to one another along the cylinder axis. By the teaching of the invention, this distortion is compensated mathematically by turning back the structures in the starting position. This is realized by comparing the respective sections of the measuring point cloud transversely to the cylinder axis via a desired / actual comparison with corresponding desired data and from this the necessary twisting position for the respective section is calculated. This is then carried out for any number of cuts through the cylinder axis or between individual cuts interpolated the twist corrected. In the lower illustration of FIG. 9, sections and reference / actual comparison and reverse rotation are shown. As mentioned, reference numeral 134 represents the measuring point cloud of a measuring object having a cylindrical shape. In this case, the measuring point cloud 134 is shown with distortion, wherein in the sections 136, 138, 140 each have a different degrees of twisting. In these sectional planes, as shown in the lower part of FIG. 9, a set point position 142 is compared with an actual point position 144, and from this the angle of rotation 146 is calculated. In this way, the various sections 136, 138, 140 are traversed and the measuring points interpolated between them. The result is a measuring point cloud with distortion correction in the cutting planes 136, 138, 140. The corrected cutting planes are identified in FIG. 9 at the top right by reference numbers 148, 150, 152. It is thus possible, for. B. the evaluation window for subsequent image processing sensors at the locations assigned to the structures according to set target data. The corrected to the point cloud 134 point cloud is provided with the reference numeral 154. FIG. 10 a shows an example of how, from an actual contour 156, by changing the curvature while maintaining the length, a better coverage to a desired contour 158 for the subsequent comparison with it can be produced. Circle 160 represents that a better adaptation to the desired contour 158 is made possible by a change in curvature at a constant length (in this case circumference).

FIG. 10 b shows how, while the curvature of the contours is maintained by changing the length of contour sections, a better overlap between desired / actual value is made possible for the purpose of the later comparison. In this case, reference symbol 162 represents the actual contour and reference symbol 164 represents the desired contour. The contour 166 is the actual contour adapted by stretching while maintaining the curvature to the desired contour 164.

According to the invention, the tolerance zones assigned to the desired or actual contour can be evaluated in the evaluation of the deviation between the nominal and actual contour. The tolerance zones are automatically taken from the dimension data of a CAD drawing or alternatively defined by operator information. With reference to the explanations to FIGS. 11 and 12, the method will be described in more detail.

Thus, in FIG. 11, a workpiece 167 comprising the elements 1 to 6 with associated dimensions (dimension 1 to dimension 4) as well as the tolerances associated with the dimensions are reproduced. The corresponding dimensions and tolerances can be taken from a CAD drawing, but alternatively also be defined by operator input. In a first step, according to the procedure of the invention, all elements in the present example are assigned a two-sided, symmetrical tolerance zone, which can have different widths per element. From Fig. 11 it can be seen that the element 1 by dimension 2 with respect to element 3 and by measure 4 with respect to element 5 two different width tolerance zones must be assigned. Analogously, the element 2 with respect to element 4 by specifying the dimension 3 and with respect to element 6 by specifying the measure 1 different tolerance zones assigned. According to the invention, the calculation and assignment of the different tolerance zones to the elements takes place automatically by analyzing all tensile dimensions defined for an element within the drawing and by automatically dividing the tolerance zones per drawing element according to the reference dimensions present for the element.

In the present example, this means that two tolerance zones are automatically defined for element 1 (see Fig. 12). The upper tolerance zone is created by the tolerance assigned to dimension 2; the lower tolerance zone is created by the tolerance assigned to dimension 4. Correspondingly, the element 2 is assigned two tolerance zones, wherein the left tolerance zone for element 2 shown in FIG. 12 arises from the tolerance zone assigned to dimension 1, the right tolerance zone for element 2 arises through the tolerance zone assigned to dimension 3. The measuring points recorded on the real workpiece 166 are assigned in a first step according to their position to one of the automatically determined tolerance zones. To check compliance with the tolerance zones, the measuring points associated with the respective tolerance zones are optimally fitted into the tolerances in the workpiece 166 defined by the nominal contour without binding degrees of freedom, wherein the fitting conditions are automatically selected depending on the type of tolerance. The corresponding check for tolerance zone evaluation is performed sequentially for all tolerance zones and all measuring points assigned to these tolerance zones.

When using image processing with autofocus sensors, there is often the problem that partially transparent layers have to be measured in terms of their height extent. For this purpose, the invention proposes that with the image processing sensor in autofocus mode for several evaluation areas simultaneously autofocus measurement points are generated at a plurality of semi-transparent layers. This is achieved by moving the image processing sensor in the measuring direction and simultaneously recording several images. The focus measuring points are calculated in the respectively determined evaluation ranges according to a contrast criterion. This is apparent from FIG. 13. An image processing sensor 168 is moved to implement an auto-focus method corresponding to the Z-axis so that the focal point 170 of the sensor 168 is placed in different positions within the semi-transparent measurement object 172. As a result, a contrast characteristic 174 is recorded. each The maximum of the contrast characteristic represents the location of the respective semi-transparent boundary layer between different types of material layer, and from this contrast curve 174, the correspondingly assigned Z positions Z1, Z2 and Z3 can then be calculated. In this case, conventional methods for contrast auto focus measurement are used.

With laser distance sensors in coordinate measuring machines, contours on workpiece surfaces are scanned in a sensory way, ie. H. In one direction, different from the sensor measuring direction, the coordinate measuring machine is moved on a predetermined path. According to the invention it is now provided that the position control of the sensor or the position control loop of the coordinate measuring machine is controlled in dependence on the deflection display of the laser distance sensor so that the deflection of the laser distance sensor remains constant. Thus, it is possible to scan contour lines on a measurement object. A corresponding contour line scanning will be clarified with reference to FIG. 14. Thus, a measuring object 176 is located on a measuring table of a coordinate measuring machine and is scanned with a distance sensor such as laser distance sensor 178 of the coordinate measuring machine. In principle, the laser distance sensor 178 is controlled in its movement so that the distance to the material surface is constant. In the specific case, the Z position of the sensor 178 is kept constant and achieved by regulating the X and Y position that the sensor measuring point always remains in a plane 180 and thus a contour line 182 is scanned on the measuring object 176.

Another problem with the use of coordinate measuring machines is that the measuring objects have to be measured from different sides. However, if the position of the measuring object in the coordinate measuring machine is changed, the reference of the measuring points is lost and a common evaluation of the measuring points is no longer possible. In order to avoid these disadvantages, the following procedure is adopted according to the invention:

Measuring the position of one or more, preferably three reference marks 184, 186 188 in the form of z. B. balls on the measuring object 190 or a measuring object 190 receiving holder 191 as frame, Storing the position in the computer of the coordinate measuring machine,

Measuring any points 194 accessible to the measuring object 190 by one or more sensors 192,

Change in the position of the measuring object 190 in the measuring volume of the coordinate measuring machine by hand or an integrated rotary axis or pivot axis (arrow 196),

re-measuring the reference marks 184, 186, 188 and determining their changed position 198, 200, 202 in the measuring volume of the coordinate measuring machine,

internal adjustment of the respective reference marks 184, 186, 188 or their positions 198, 200, 202 in such a way that there is a minimized shift between these software-internally,

Measuring further points 204 on the measuring object 190 with one or more sensors 192 of the coordinate measuring machine,

Repetition of the above-mentioned processes in any number, joint evaluation of all, during the measurement cycles described above measuring points 194, 204 of the measuring object 190 in a coordinate system.

Coordinate measuring machines with various sensors also have, among other things, optionally sensors with an opto-tactile button. In this case, the determination of the position of the Antastformelementes (ball or cylinder) by an image processing sensor. The problem is to adjust this sensor to the position of the probe ball. This can be achieved by additionally arranging an adjusting unit on the coordinate axis bearing the sensor, which device sets a relative position between the sensing element (probe ball including stylus and holder) in the image frame. processing sensor allows. For example, via an autofocus method is then an automatic focus of the Antastformelementes in relation to the image processing sensor possible.

Thus, in Fig. 16, a tactile-optical sensor 210 (also called opto-tactile sensor) arranged in a coordinate measuring machine on an adjustment axis 208, which is mounted on a coordinate axis of the coordinate measuring machine, preferably the Z-axis 208, in the embodiment with the optical axis of an optical sensor 210 coincides. By separately controlling a second Z-axis (actuator 210), it becomes possible to selectively adjust the relative position between the probe form element 212 of the tactile optical sensor 206 to the focal plane 214 of the optical sensor 210.

Coordinate measuring machines are generally exposed to different operating temperatures at the place of use. If several sensors are attached to the coordinate measuring machine, this will cause thermally induced changes in the positions between the different sensors. This leads to measurement errors. To compensate for this, the temperature of the mechanical assemblies required for mounting the various sensors is measured at one or more locations and the expansion of the corresponding mechanical components is taken into account in the calculation of the measurement points detected by the various sensors.

For example, FIG. 17 shows an arrangement with two sensors 218, 220 on a Z axis 222 of a coordinate measuring machine. The sensors 218, 220 are one or more connecting elements 224 connected to each other and the Z-axis 222. By means of a temperature sensor 226, the temperature of the connecting element or elements 224 is measured continuously during the measurement, and the corresponding change in length is corrected by an evaluation computer 228 and taken into account for the measurement results.

In order to be able to measure a measuring object from several sides during the measurement on a coordinate measuring machine, it makes sense that the measuring object is clamped in an axis of rotation and thus in an optimal for the measurement with the various sensors Position can be screwed. In addition to this, it is possible to record the measurement object in addition to the rotation axis itself with a correspondingly arranged counter-tip. When clamping a test object between tips, however, the problem arises that the clamping force of the opposite tip can lead to deformations of the test object. In order to exclude errors caused by this, it is proposed that the measured object is constantly deformed or the counter-tip is automatically positioned up to a predefined force on the measurement object. In this case, the counter-tip can be mounted sprung, so that via a deflection and a corresponding limit switch, the corresponding required force can be determined.

Thus, FIG. 18 shows how, during the clamping of a measuring object 230, tip 232 and counter-tip 234 are pushed to a point by a guide 236 against the measuring object 230 until the counter-tip 234 interacts with a limit switch 238. It can be z. B. a bias voltage by means of a biasing spring 240 are generated, wherein the feed movement (arrow 242) of the opposite tip 234, which is achieved by a corresponding drive 244 on the guide 236, then interrupted when the opposite tip 234 on the limit switch 238 or a gleichwirkendes Element acts. As a result, the biasing force of the clamped measuring object 236 is clearly defined.

Another problem with the use of coordinate measuring machines is that often several contours are to be measured close to each other. This often leads to considerably longer measurement times for the required number. According to the invention, it is provided that a plurality of tactile sensors of similar or different construction are arranged close to one another on a common mechanical axis of the coordinate measuring machine. Fig. 19 shows an example. Thus, a plurality of tactile sensors 248, 250, 252 are arranged on a common Z-axis 254 of a coordinate measuring machine. When a measuring object 256 is touched, measuring points 258, 260, 262 are simultaneously measured for different positions, which are then evaluated together in the coordinate measuring machine. When measuring with an image sensor on outer edges of workpieces such as cutting tools, the problem is that the image processing sensor is permanently refocused on the outer edge to be measured. In order to avoid this disadvantage, it is provided that a laser distance sensor is additionally integrated in the image processing beam path. The laser sensor measures the distance of the image processing sensor to the workpiece surface in the vicinity of the outer edge to be measured and is connected to a position control loop of the coordinate measuring machine in such a way that automatic tracking takes place. The image processing sensor is thus permanently focused. This will be clarified in principle with reference to FIG. On a Z-axis 258 of a coordinate measuring machine, two combined sensors 260, 262 for image processing and laser distance measurement are combined, which detect measurement points on a tool 266 via a common optical system 264. The axis of rotation 268 of the tool 266 is controlled by a computer and control system 270 of the coordinate measuring machine, which also has the sensor signals of the CMM, so that measured by the laser distance sensor 262 measuring points on a rake face 272 of the tool 266 influence the settings of the rotation axis 268 so in that the cutting edge comes to rest here in each case in the section plane 274 of the tool. With the image processing sensor 260 of the same coordinate measuring machine, it is thereby possible to measure the outer contour of the corresponding tool. With constant turning and moving of the X, Y and Z axes of the CMM, this process can be repeated continuously, thus performing scanning in all three coordinates simultaneously.

In a coordinate measuring machine according to the invention, image processing sensors with laser sensors integrated in the beam path can be used. In practically used systems, it is to be expected that the desired optical properties for the integrated laser distance sensor and the image processing sensor will not be present at the same setting parameters (working distance / magnification). By additionally exchangeable optical attachment optics and aperture of the zoom optical system used can alternatively be optimized for the laser sensor and the image processing sensor. Thus, FIG. 21 shows an image processing sensor 276 and a laser distance sensor 278 which are inserted via a beam splitter 280 with a common measuring objective 282 in a coordinate measuring machine. In this case, a measurement object 284 is to be touched, that is to be measured without contact in the present case. By replacing an additional pre-optics 286, which can be stored in a changing station 288, it is possible to change the optical properties of the total beam path. This is determined by the measuring objective 282 and by the optical system 286 located or not in its beam path. As a result, an optimization of the setting parameters for the laser distance sensor 278 with upstream pre-optics 286 or for the image processing sensor 276 with removed pre-optics 286 or vice versa.

If the surface contour of workpieces is measured with an autofocus sensor, the measuring points are usually specified by the operator in the teach-in mode. If unknown contours are to be measured in this method, this is only possible with difficulty. In order to avoid this, it is proposed according to the invention that a scanning process of a material surface is performed with an autofocus sensor by theoretically calculating from the already measured focus points by extrapolation the prospective location of the next measurement point and measuring it accurately by a new autofocus point. If this process is repeated several times in succession, this results in a fully automatic scanning. In this case, both the number of points to be scanned along a line and an area to be scanned on the workpiece or measured object can be specified by the operator. The extrapolation of the next measurement point from the two or more preceding measurement points can be done by a linear extrapolation.

Thus, Fig. 22 shows a corresponding method for scanning a material surface with an autofocus sensor. An autofocus sensor 290 is used in a first location 191 by movement in the Z-axis of the coordinate measuring machine to measure a surface point. For this purpose, the contrast behavior is recorded via a focus area 292 and from this the focus location 294 is calculated in accordance with the measurement point. The same process is repeated at a next position 295 with corresponding Focusing range 296 and measuring point 298. By z. B. interpolation of a line 300, the position of the focus measuring range 302 and thus the sensor 290 is defined in the position 304 and there a measuring point 306 measured. This process is repeated one after the other until the entire length of the contour 308 of the object to be measured or of a part thereof has been measured.

When using image processing sensors or X-ray tomography sensors, the problem arises that, depending on the property of the measurement object within an image, there are regions with both strong and weak intensities. This is caused by the different reflection or transmission properties of the materials. As a result, only small signals are present for the "dark" image areas with the resulting poor signal-to-noise ratio, however, stronger illumination or irradiation of the object would lead to overshoot in the bright areas and thus preclude.

In order to avoid these disadvantages, it is provided that several images with different illumination intensities are recorded for each person in the image section. Subsequently, these images of the same object area are merged into a new overall image such that the pixel amplitudes are normalized to the particular illumination intensity that was used. For overall image composition, the pixels on the respective image that are within the allowed dynamic range are then used. Overshoot amplitudes are not taken into account in the respective picture.

Accordingly, an X-ray source 308, a turntable 310 with a measurement object 312, and an X-ray sensor 314 are shown in FIG. The pixel amplitude of the X-ray detector 314 is stored in a computer and evaluation system 316 and evaluated according to previously explained method steps and joined together. In this case, it is possible to control the X-ray frequency of the radiation source 308 as well as the recording parameters of the detector 316 in accordance with the procedure described by the evaluation system 316.

Claims

claims

1. A method for measuring workpiece geometries with a coordinate measuring machine with movable track axes and one or more sensors for detecting measuring points on the workpiece surfaces, characterized in that a sensor image processing sensor and / or a switching touch probe and / or a measuring touch probe and / or a in the image processing sensor integrated laser distance sensor and / or a separate laser distance sensor and / or a white light interferometer and / or a tactile optical button, in which the position of the Antastformelementes is determined directly by an image processing sensor, and / or a punctiform interferometer sensor and / or a punctiform working Interferometer sensor with integrated rotation axis and / or a punctiform interferometer sensor with angled viewing direction and / or an X-ray sensor and / or a chromatic focus sensor and / or a confocal scanning probe are set, with type and number of or the sensors used is selected in each case to be solved measurement task.

2. The method according to claim 1, characterized in that a sensor or a plurality of sensors are provided with an exchange interface and are replaced manually or automatically.

3. The method of claim 1 or 2, characterized in that camera of the image processing sensor with a larger resolution (number of pixels) is selected as the resolution of the monitor used or the monitor section used for the image display. 4. The method according to at least claim 3, dadur ch characterized in that a camera with random access to certain sections of the overall image is used.

5. The method according to at least one of the preceding claims, characterized in that in the live image or observation image of the coordinate measuring machine only a section of the overall image, enlarged to the format of the display window is displayed.

6. The method according to at least one of the preceding claims, characterized in that the magnification between the measurement object and monitor image by changing the selected section of the camera image is controlled by the software and / or the live image is displayed in the same way.

7. The method according to at least one of the preceding claims, characterized in that the magnification between the measurement object and monitor image is controlled by changing the selected section of the camera image by the software and / or the live image is displayed in the same way and the operation of the cropping size preferably via a rotary knob or software controller.

8. The method according to at least one of the preceding claims, characterized in that when using a high-resolution camera, the image / image section is displayed only in the lower resolution of the monitor, in the background, however, the full resolution of the camera for digital image processing is used. , Method according to at least one of the preceding claims, characterized in that the actual optical magnification of the imaging optics of the image processing sensor is relatively low (typically 1-fold, but at most <5-fold) and by displaying only a section of the high-resolution camera image on the lower resolution Monitor the optical effect of a higher magnification is achieved.

10. The method according to at least one of the preceding claims, characterized in that in an optical beam path more, but at least 2 cameras are integrated via mirror systems and use the same imaging lens.

11. The method according to at least claim 10, characterized in that in addition a laser distance sensor is integrated and also uses the same imaging lens.

12. The method according to at least one of the preceding claims, characterized in that cameras are used with different chip size with the same number of pixels or with different number of pixels with the same chip size or both.

13. The method according to at least one of the preceding claims, characterized in that in each camera beam path additionally a Nachvergrößerung or reduction is integrated.

14. The method according to at least one of claims 10 to 13, characterized in that used for the division of the different camera beams optical splitters are designed so that all cameras receive the same light intensity. 15. The method according to at least one of claims 10 to 14, characterized in that in addition a Hellfeldauflichtstrahlengang is integrated into the overall system.

16. Method according to claim 1, characterized in that a number of pixels required according to the resolution of the evaluation or display area is calculated by re-sampling from the image recorded with a high-resolution camera.

17. The method according to at least one of the preceding claims, characterized in that recorded with one or more sensors of the CMM measurement points or video images or X-ray images and the associated positions and other technology parameters of the CMM recorded and stored and for later evaluation of Will be provided.

18. The method according to claim 17, characterized in that with the image processing sensor a plurality of partial images of a measurement object are individually measured and combined to form an overall image of the entire object or of partial areas of the overall object, are stored and later fed to an evaluation on a separate evaluation computer.

19. Method according to claim 17, characterized in that the entire measuring sequence including driving positions of the coordinate measuring machine and / or the images of the image processing sensor and / or the images of the x-ray sensor and / or the tactile points of the tactile sensor and / or the touch points the laser sensor and / or other technology parameters. stored and manually corrected in later computer runs or supplemented by additional evaluations, including the meter itself and / or offline on a separate computer.

20. The method according to at least one of the preceding claims, characterized in that when using the image processing sensor in the event that the field of view of the camera is not sufficient to capture the defined by selecting the desired evaluation area (image processing window) area of the measurement object at once, automatically an image is composed of several partial images. and then presented to the user as a measured image and made available for evaluation.

21. The method according to at least one of the preceding claims, characterized in that, when measuring with the image processing sensor, the following method steps are carried out successively:

1. Search of the measurement object in the measuring range of the coordinate measuring machine by driving a sensor, in particular image processing sensor, on a straight, spiral, meandering, circular arc or stochastic or other kind of search path until the existence of a measured object is detected;

2. Starting a scanning of the outer contour of the measurement object (contour tracking for detecting the geometry and position of the outer contour of the measurement object);

3. Optionally detecting the measuring points located inside the outer contour on the test object by scanning with an image processing sensor and / or scanning with other sensors. 22. The method according to at least one of the preceding claims, characterized in that the characteristics of the illumination devices of the Bildverarbeitungsstrah- lergangs, that is, the dependence of the illumination intensity of the set value of the user interface of the meter, detected by measuring the intensity of the associated set value with the image processing sensors and in the computer the meter is stored.

23. The method according to at least claim 22, characterized in that the characteristic curves are stored in a light box, which performs the control of the illumination intensity of the different illumination channels.

24. The method according to at least one of the preceding claims, characterized in that the light characteristics of the illumination systems of the coordinate measuring machine are standardized by measurements on a uniform or calibrated in its reflection behavior object for multiple devices and so the portability of programs between these devices is ensured.

25. The method according to at least one of the preceding claims, characterized in that during operation of the coordinate measuring device, the previously measured light characteristic is taken into account for correction calculations that apparently a linear characteristic for the operator exists (set value and the illumination intensity then follow a linear relationship).

26. The method according to at least one of the preceding claims, characterized in that the increase of the linear characteristic for several devices is adjusted by a correction factor. 7. The method according to at least one of the preceding claims, characterized in that during execution of programs for the operation of the coordinate measuring machine with image processing sensor, the following method steps are followed when measuring individual positions:

1. setting the predetermined intensity of the illumination source or sources of illumination stored in the program;

2. Measure the illumination intensity with the image processing sensor and check whether this measured value corresponds to the stored setpoint or setting value;

3. If the deviation between the setpoint and the actual value exceeds a specified amount, the setting value of the illumination intensity is corrected linearly or, according to the detected characteristic, the illumination system so that the desired intensity value is achieved as stored in the program;

4. measuring the desired object feature;

5. Repetition of this process according to the program specification.

28. The method according to at least claim 27, characterized in that for the realization of the described light control process in each case only a first image for recording the intensity and after the adjustment process, a second image is taken for measuring.

29. The method according to at least one of claims 22 to 28, characterized in that in the coordinate measuring machine several sets of characteristics are deposited, which correspond to the behavior of other similar coordinate measuring machines, for processing of measuring programs of the coordinate measuring machine on one of the other coordinate measuring machines. 30. The method according to at least the preceding claim, characterized in that are detected with one and / or multiple sensors contours on workpiece surfaces.

31. The method according to at least claim 30, characterized in that with one or more of the sensors of the coordinate measuring machine measured contours a direct comparison to a predetermined desired contour is performed.

32. The method according to at least one of the preceding claims, characterized in that, when evaluating the deviation of measured actual contours and target contours, an automatic fit between desired and actual takes place.

33. The method according to at least one of the two preceding claims, characterized in that in the Best-fitting between the target and actual contour in addition to the Relativlageveränderung between nominal and actual contour and the length of contour sections corresponding to the desired length while maintaining the Curvature and / or the contour curvature while maintaining the contour length on the actual contour is changed so that an optimal coverage is achieved with the desired contour.

34. Method according to claim 30, characterized in that the fit between actual and desired contour or a group of actual and desired contours of the individual excellent features, such as crossing points of contours or circular structures or other recurring structures , and so a distortion of the actual contour for optimal coverage with the target contour is generated. 35. The method according to at least one of the preceding claims, characterized in that the actual contour is partially rotated or screwed for optimum coverage with the desired contour in a cylinder-shell surface.

36. The method according to at least one of the preceding claims, characterized in that in the evaluation of the deviation between the nominal and actual contours of the target or actual contour associated tolerance zones are evaluated.

37. The method according to at least one of the preceding claims, characterized in that the tolerance zones are calculated automatically from the dimensional information of a drawing such as CAD drawing for dimensional tolerance, shape tolerance and position tolerance.

38. The method according to at least one of the preceding claims, characterized in that each setpoint or actual contour segment are assigned a plurality of tolerance zones.

39. The method according to at least one of the preceding claims, characterized in that for several, grouped together in groups target or actual contour regions and / or complete workpiece target and actual contours each several different position, Maß- and / or Shape tolerance situations according to the tolerance zone systems are evaluated automatically one after the other.

40. Method according to at least one of the preceding claims, characterized in that that before each desired or actual contour segment, the most unfavorable result of the different SollVIst comparisons is displayed with the aid of the various tolerance zones.

41. The method according to claim 1, wherein with an image processing sensor in autofocus mode, autofocus measurement points are generated simultaneously on a plurality of semitransparent layers for a plurality of evaluation regions.

42. The method according to at least one of the preceding claims, characterized in that with a laser distance sensor in the scanning mode scanning along one or more contour lines is performed on the measurement object.

43. The method according to at least one of the preceding claims, characterized in that the position control loop of the coordinate measuring machine in response to the deflection display of the laser distance sensor is controlled so that the deflection of the laser distance sensor remains constant and this moves the axes of the coordinate measuring perpendicular or nearly perpendicular to the measuring direction of the laser distance sensor become.

44. The method according to at least one of the preceding claims, characterized in that the coordinate measuring machine is used in the following method steps:

1. Measuring the position of one or more, preferably three, reference marks, such as balls, on the measurement object or stationary associated with the measurement object; 2. storing this position in the computer of the coordinate measuring machine;

3. measuring any points accessible by one or more sensors on the object to be measured;

4. Change the position of the measuring object in the measuring volume of the coordinate measuring machine by hand or z. B. an integrated axis of rotation or pivot axis;

5. Re-measuring the reference marks and determining their changed position in the measuring volume of the CMM;

8. repetition of the above processes in any number;

9. Joint evaluation of all measuring points of the measuring object acquired during the measuring cycle in a coordinate system.

45. The method according to at least claim 44, characterized in that the reference marks are measured like balls by a sensor and the measurements are performed on the workpiece by one of the other sensors. 46. The method according to at least one of the preceding claims, characterized in that a tactile-optical sensor is used as the sensor, that the tactile-optical sensor, in which the position determination of its Antastformelements as probing ball takes place directly by measurements with the image processing sensor, with its adjustment axis (Coordinate axis) is placed on another, already existing coordinate axis and at their respective position, a relative movement of the tactile-optical sensor to the optical beam path is made possible.

47. Method according to claim 1, characterized in that the probing element of the tactile sensor precisely detects in its deviations from the desired geometry, such as nominal spherical shape or nominal cylindrical shape, on an external measuring station and corrects these deviations when used in the coordinate measuring machine becomes.

48. The method according to at least one of the preceding claims, characterized in that the deviations of the actual geometry of the ideal target geometry of the sensing element are detected by measurements on a highly accurate calibrated normal within the coordinate measuring machine itself.

49. The method according to at least one of the preceding claims, characterized in that a changing device is provided for the replacement of different sensors or sensing elements.

50. The method according to at least claim 49, characterized in that the changing device is retracted by means of a separate adjustment axis in the measuring volume of the coordinate measuring machine. 51. The method according to at least one of the preceding claims, characterized in that the adjustment axis is carried out with a spindle drive.

52. The method according to at least one of the preceding claims, characterized in that the adjustment axis is realized with a drive with 2 stops.

53. The method according to at least one of the preceding claims, characterized in that to compensate for error effects caused by temperature fluctuations at the installation of the coordinate measuring machine, the temperature of the mechanical assemblies used to attach the various sensors at one or more locations, and the extent of the corresponding mechanical components are taken into account in the calculation of the measurement points detected by the various sensors.

54. The method according to at least claim 53, characterized in that the temperature compensation takes place linearly multiplicatively.

55. Method according to claim 1, characterized in that the measurement object is clamped in a rotation axis during the measurement process and measurement results caused by the rotation axis or clamping are included in the overall evaluation.

56. The method according to at least claim 55, characterized in that the measurement object is received between a tip arranged in a rotation axis and a counter-tip. 57. The method according to at least claim 55 or claim 56, characterized in that during clamping of the test object between the tip and the counter-tip, the counter-tip is automatically moved to a deflection defined by a limit switch against the test object.

58. The method according to at least one of claims 55 to 57, characterized in that the counter-tip is pressed with spring tensioner against the measurement object.

59. The method according to at least one of the preceding claims, characterized in that a plurality of similar tactile sensors are arranged close to each other on a common mechanical axis of the coordinate measuring machine.

60. The method according to at least one of the preceding claims, characterized in that a plurality of tactile sensors are arranged on a rotary pivot unit.

61. The method according to at least one of claims 59 or 60, characterized in that contours are simultaneously recorded on workpiece surfaces in the scanning operation with a plurality of arranged on an axis tactile sensors.

62. The method according to at least one of claims 59 to 61, characterized in that in the scanning mode, the movement of the coordinate axes of the coordinate measuring machine via at least one sensor, preferably exclusively via a sensor is controlled. 63. The method according to at least one of claims 59 to 62, characterized in that at the same time measuring points for generating a plurality of measuring tracks are recorded with further sensors.

64. The method according to at least one of claims 59 to 61, characterized in that the control of the rotary pivot joint of the multi-sensor arrangement is controlled by the difference between the mean deflections of the individual sensors.

65. The method according to at least one of claims 59 to 64, characterized in that the multiple sensor arrangement tooth flanks of gears or cams of camshafts simultaneously several measurement tracks per measurement operation are measured.

66. The method according to claim 1, characterized in that the laser distance sensor and image processing sensors are used in measurements of tools so that the external contour is measured with the image processing sensor and the axes of the coordinate measuring machine are tracked simultaneously with the laser distance sensor so that the image processing sensors in Focused area of the tool contour to be measured.

67. The method according to at least claim 66, characterized in that when using a rötationssymmetrischen tool as the measurement object, the focusing is realized by rotating the rotationally symmetrical tool. 68. The method according to at least claim 66, characterized in that when using nichtrotationssymmetrischen tool as the measurement object, the focusing is achieved by adjusting the Z-axis of the coordinate measuring machine when measuring the non-rotationally symmetrical tool.

69. The method according to at least one of the preceding claims, characterized in that the image evaluation of the image processing sensor in the same frequency as the refresh rate of the camera is performed (video real-time).

70. The method according to claim 69, characterized in that the measurement object is rotated during the measurement with a rotation axis and recorded and / or evaluated with the frequency of the camera measurement points on the outer edge of the measurement object for realizing a roundness measurement in video real time.

71. The method according to at least one of the preceding claims, characterized in that to improve the signal to noise ratio of image processing sensors or X-ray sensors, the integration time is extended until a sufficiently low signal-to-noise ratio is generated.

72. The method according to at least claim 71, characterized in that the integration time of the camera is extended until a sufficiently good image can be stored and further processed, wherein the intensity of the pixels of the image is increased up to a desired value. 73. Method according to claim 1, characterized in that a laser distance optic with a zoom optic of an image processing sensor uses a common beam path.

74. The method according to at least claim 73, characterized in that the working distance of the zoom optics used is adjustable.

75. The method according to at least one of claims 73 and 74, characterized in that optionally an attachment optics is loaded, is changed over the aperture and / or working distance of laser distance sensor and image processing sensor optics.

76. The method according to at least one of claims 73 to 75, characterized in that the optical system is optimized by replacing the attachment optics for the operation of the laser distance sensor.

77. The method according to at least one of claims 73 to 76, characterized in that the attachment system is connected via a magnetic interface with the zoom optics.

78. The method according to at least one of claims 73 to 77, characterized in that the attachment optics can be loaded via a also used for tactile sensors probe changer. 79. The method according to at least one of the preceding claims, characterized in that for generating an optimum contrast for the image processing sensor successively taken multiple images with different sources of illumination, taken from each image, the areas with optimal contrast and combined to form a contrast-optimized overall picture.

80. Method according to claim 79, characterized in that different images of the same object or object detail are recorded by using different illumination directions of a dark field illumination and / or different illumination angles of a dark field illumination and / or use of bright field illumination and the contrast-optimal regions of the individual images to form an optimized overall image be joined together.

81. The method according to claim 79, wherein for each pixel of the resulting overall image or for each location of each resulting pixel of the overall image, that pixel with the same location is selected from the individual images generated with different illumination, which optimum contrast in its environment.

82. The method according to at least claim 81, characterized in that the evaluation of the optimum contrast by determining the amplitude difference between the respective considered pixels and the adjacent pixels is performed.

83. Method according to at least one of the preceding claims, characterized in that that with an autofocus sensor, a scanning process on the material surface is carried out by theoretically calculated from previously measured focus points by extrapolation, the probable location of the next measurement point and accurately measured by a new autofocus point and this process is repeated several times according to user preference.

84. The method according to at least claim 83, characterized in that in the extrapolation of the next measuring point, a linear extrapolation from the last two measured measuring points is used.

85. The method according to at least one of claims 83 to 84, characterized in that in the extrapolation of the point to be re-measured a polynomial interpolation from the last measured two or more points is used.

86. The method according to at least one of claims 83 to 85, characterized in that during each focusing operation several focus points are measured simultaneously and thus a sequence of measuring points is generated.

87. The method according to at least claim 86, characterized in that a plurality of such sequences are juxtaposed and thus a scan of a complete contour can be realized.

88. The method according to claim 1, characterized in that for the quality optimization of recorded images in image processing sensors or X-ray tomography sensors, a plurality of images of an object area are recorded, each with different illumination or radiation intensities, and these are then combined to form an overall image. 89. Method according to at least claim 88, characterized in that the pixel amplitudes (pixels) which are within a valid amplitude range (typically between 0 and 245) defined as valid are taken from each individual image.

90. Method according to at least one of claims 88 to 89, characterized in that pixel amplitudes with amplitude values which indicate overshoot (eg> 245) are disregarded in the evaluation.

91. The method according to at least one of claims 88 to 90, characterized in that in the presence of a plurality of valid pixel amplitudes from the normalized pixel amplitudes, an average value we formed.

92. Method according to claim 88, characterized in that corresponding calculations are calculated in amplitude values normalized to the used radiation or illumination intensity.

93. Coordinate measuring device (10) for measuring workpiece geometries with movable track axes and one or more sensors (30) for detecting measuring points on the workpiece surfaces, characterized in that as a sensor in the coordinate measuring machine (10) an image processing sensor system (168, 260, 276) and / or a switching touch probe and / or a measuring touch probe (30) and / or a laser distance sensor (262, 278) integrated in the image processing sensor system and / or a separate laser distance sensor (290) and / or a white light interferometer and / or a tactile sensor optical probe, in which the position of the Antastformelementes directly by an image processing sensor (208) is determinable, and / or a punctiform interferometer sensor and / or a punctiform interferometer sensor with integrated axis of rotation and / or a punctiform interferometer sensor with angled viewing direction and / or an X-ray sensor (308, 314) and / or a chromatic focus sensor and / or a confocal scanning probe is mounted.

94. Coordinate measuring machine according to claim 93, characterized in that one or more sensors (34, 36, 38) provided with an exchange interface and manually or automatically interchangeable.

95. Coordinate measuring machine according to at least one of claims 93 and 94, characterized in that the camera (48) of the image processing sensor has a greater resolution (number of pixels) than the resolution of a monitor used (52) or a monitor section used for image display.

96. coordinate measuring machine according to at least claim 93 to 95, characterized in that a camera with random access to certain sections of the overall picture, z. B. CMOS camera, is used.

97. coordinate measuring machine according to at least one of claims 93 to 96, characterized in that in the live image or observation image of the coordinate measuring machine, only a section of the overall image is displayed.

98. coordinate measuring machine according to at least one of claims 93 to 97, characterized in that the magnification between the measurement object (16) and monitor image by changing the selected section of the camera image is software controlled and / or the live image is displayed in the same way. 99. coordinate measuring machine according to at least one of claims 93 to 98, characterized in that the magnification between the measurement object (16) and monitor image by changing the selected section of the camera image is software controlled and / or the live image is displayed in the same way and to operate the Section size a knob (54) is connected or a software controller exists.

100. coordinate measuring machine according to at least one of claims 93 to 99, characterized in that for the image processing sensor, a camera with a higher resolution than standard video standard, zB1200x600 pixels, can be used, the camera image on the computer monitor (52) with a Grafϊkkarte or graphics setting lower resolution is displayed and in the background, an image processing computer with an associated image memory according to the full size of the high-resolution camera for digital image processing is used.

101. coordinate measuring machine according to at least one of claims 93 to 100, characterized in that the actual optical magnification of the imaging optics of the image processing sensor (48) is relatively low (typically 1-fold, but at most 5-fold) and the representation of only a section of the high-resolution camera image on the lower resolution monitor (52).

102. coordinate measuring machine according to at least one of claims 93 to 101, characterized in that in an optical beam path a plurality, but at least 2 cameras (48, 58) via mirror systems (56) are integrated and the beam path uses the same imaging lens (46). 103. coordinate measuring machine according to at least claim 102, characterized in that in addition at least one further mirror (64) a Laserabstandssen- sor (60) is integrated, which uses the same imaging lens (46).

104. The coordinate measuring machine according to claim 100, characterized in that cameras (48, 58) with different chip sizes can be used for the same number of pixels or with different number of pixels for the same chip size or both.

105. Coordinate measuring device according to at least one of claims 100 to 104, characterized in that in each camera beam path additionally Nachvergrößerungsoptik (62) or reduction optics is integrated.

106. Coordinate measuring machine according to claim 100, characterized in that optical dividers (56, 66) used for the division of the different camera beams are designed with respect to their transmission and reflection in such a way that all the cameras (48, 58) have the same light intensity receive.

107. coordinate measuring machine according to at least one of claims 100 to 106, characterized in that in the overall system in addition a Hellfeldauflichtstrahlengang (60, 64) is integrated.

108. coordinate measuring machine according to at least one of claims 100 to 107, characterized in that the coordinate measuring machine with an image memory for storing a plurality of individually measured sub-images (102, 104, 106, 108) of a measurement object (96) is equipped and has an image processing evaluation computer , of the can access all of these memory areas together and allows an evaluation as on a single overall picture.

109. Coordinate measuring machine according to claim 100, characterized in that the coordinate measuring machine comprises a memory for the driving position of the coordinate measuring device and / or a memory for the images of an image processing sensor and / or a memory for the images of an x-ray sensor and / or or a memory for the measured touch points of a tactile sensor and / or a memory for the touch points of the laser sensor and / or a memory for further technology parameters of the coordinate measuring machine and further has the ability to perform a Gesamtauswertung after recording the measured values via a connected evaluation computer.

110. coordinate measuring machine according to at least one of claims 100 to 109, characterized in that an image processing memory is implemented in which a plurality of sub memory for images of an image processing sensor are joined together in the correct location, wherein the position of the image processing sensor is included in the coordinate measuring machine by reading the scales and the associated Display for the operator is designed so that the impression of a single overall picture arises.

111. coordinate measuring machine according to at least one of claims 100 to 110, characterized in that in the coordinate measuring a memory for the characteristic of the different illumination sources exists and this memory is associated with the signal paths for adjusting the illumination intensity in real time associated with the various light sources and thus the set values corrected depending on this characteristic memory. 112. coordinate measuring machine according to at least one of claims 100 to 111, characterized in that on the measurement object (190) preferably three reference marks are mounted and / or for receiving the measurement object a receiving frame (191) with a plurality, preferably three reference marks (184, 186 , 188) preferably in the form of spheres or corresponding reference marks or features are provided for attachment to the measurement object.

113. coordinate measuring machine according to at least claim 112, characterized in that the workpiece frame (191) is clamped in a rotary or rotary pivot axis.

114. coordinate measuring machine according to at least one of claims 112 and 113, characterized in that in the coordinate measuring device, a memory for the measured positions of the reference marks (184, 186, 188) an arbitrary number of positions of the reference frame (191) is provided.

115. Coordinate measuring machine according to claim 112, characterized in that the tactile-optical sensor (206), in which the position determination of the probe form element (212) takes place directly by measurements with the image processing sensor (208), with its adjustment axis (210 ) (Coordinate axis) is placed on a further, already existing coordinate axis (216) and at their respective position allows a relative movement of the tactile-optical sensor to the optical beam path.

116. coordinate measuring machine according to at least one of claims 100 to 115, characterized in that a memory for geometric deviation of the probe form element of a tactile sensor is provided in the coordinate measuring machine, which is connected to the evaluation computer for determining the geometry features.

117. Coordinate measuring device according to at least one of claims 100 to 115, characterized in that a changing device (42) for the replacement of various sensors (34, 36, 38) or sensing elements is provided.

118. Coordinate measuring machine according to at least one of claims 100 to 117, characterized in that the changing device (42) by means of a separate adjustment axis (44) is retractable into the measuring volume of the coordinate measuring machine.

119. Coordinate measuring device according to at least one of claims 100 to 118, characterized in that the adjustment axis (44) is designed with a spindle drive.

120. Coordinate measuring device according to at least one of claims 100 to 119, characterized in that the adjustment axis (44) is realized with a drive with two stops.

121. Coordinate measuring machine according to claim 100, characterized in that mechanical assemblies (244) which serve for fastening various sensors (218, 210) are equipped with one or more temperature sensors (226), wherein the sensors are connected to the Evaluation of the coordinate measuring machine are connected.

122. Coordinate measuring device according to at least one of claims 100 to 121, characterized that the measurement object is clamped in a rotation axis during the measurement process and measurement results of the rotation axis can be included in the overall evaluation.

123. Coordinate measuring device according to at least claim 122, characterized in that the measuring object between a arranged in a rotation axis tip (232) and a counter-tip (234) is added.

124. Coordinate measuring machine according to at least claim 123, characterized in that during clamping of the measuring object between the tip (232) and counter-tip (234), the counter-tip is designed to be movable up to a defined by a limit switch (238) deflection against the measurement object.

125. Coordinate measuring device according to at least one of claims 123 and 124, characterized in that the counter-tip (234) with spring tensioner (240) can be pressed against the measurement object.

126. Coordinate measuring machine according to at least one of claims 100 to 125, characterized in that a plurality of similar tactile sensors (248, 250, 252) are arranged close to each other on a mechanical axis (254) of the coordinate measuring machine.

127. Coordinate measuring device according to at least one of claims 93 to 126, characterized in that a plurality of similar tactile sensors (248, 250, 252) are arranged on a rotary pivot unit.

128. coordinate measuring machine according to at least one of claims 126 to 127, characterized a first probe of a multiple probe arrangement is connected to the position control loop of the control and the other probes are connected to a position measuring electronics of the coordinate measuring machine.

129. Coordinate measuring device according to one of the preceding claims, characterized in that a laser distance optics (278) with a zoom lens (282) for image processing (276) forms a common beam path.

130. Coordinate measuring device according to one of the preceding claims, characterized in that the working distance of the zoom lens (282) used by adjustment of lens groups is also adjustable.

131. Coordinate measuring device according to at least one of claims 129 and 130, characterized in that optionally an attachment optics (286) can be exchanged.

132. coordinate measuring machine according to at least claim 131, characterized in that the optical system is optimized by replacing the attachment optics (286) for the operation of the laser distance sensor (278).

133. Coordinate measuring machine according to at least claim 131, characterized in that the attachment optics (286) via a magnetic interface with the zoom optics (282) is connected.

134. Coordinate measuring machine according to at least claim 131, characterized in that the attachment optics (286) is passable via a probe changer used for tactile sensors.