DE102019220060A1 - Method for calibrating a tactile sensor - Google Patents

Abstract

A method (110) for calibrating a tactile sensor (112) with at least one probe body (114) is proposed. The method (110) has the following steps: a) generating at least one data set (122), the generating comprising scanning a calibration body (120), the probe body (114) along at least one trajectory along a surface of the calibration body (120) ) is moved and a plurality of measured values is recorded, the speed and contact force of the tactile sensor (112) being varied during scanning, b) evaluating the data record (124), the evaluation of the data record being a determination of a tactile vector, at least one characteristic, geometric Size of the probe body, a static compliance of the tactile sensor (112) and a dynamic compliance of the tactile sensor (112).

Description

Technical area

The invention relates to a method for calibrating a tactile sensor, a computer program and a coordinate measuring device for measuring at least one workpiece. The present invention relates in particular to the field of coordinate measuring technology using a tactile coordinate measuring machine.

Technical background

Various devices and methods for measuring workpieces are known from the prior art. For example, coordinate measuring machines with tactile sensors are used which touch a surface of a measurement object, for example mechanically. Such tactile sensors typically have a probe body in the form of a probe ball which is attached to a transmission element. When the probe ball is probed with the workpiece, the forces on the probe ball are measured in three axes and a direction vector of the probe, the so-called probe vector, is determined from this and the workpiece is measured in this way.

In order to achieve precise measurement results, every tactile sensor that is to be used in a coordinate measuring machine or in a machine tool must be calibrated. For this purpose, at least the following key figures are basically determined: probe ball radius, probe vector, static compliance of the tactile sensor and dynamic compliance of the tactile sensor. It is known that these key figures can be determined using a two-stage process. First, the probe vector, the probe ball radius and the static flexibility are determined from a data record in which the calibration ball is scanned with individual points or, for example, in scanning mode at slow speed and with different forces. In a second step, after information has been successfully determined from the first step, the dynamic flexibility of the tactile sensor is determined by scanning the calibration ball at different speeds.

Describes for example DE 19 861 469 a method for calibrating the tactile sensor of an electronically controlled coordinate measuring machine with a spherical calibration body of known geometry, comprising the following method steps: moving the probe head along a path in such a way that at least parts of the surface of the calibration body are continuously scanned by the tactile sensor along a line, with the line is designed in such a way that it is not restricted to one plane, and the line has a plurality of partial lines that result when vertical planes intersect with the spherical surface - calculation of the calibration data assigned to the tactile sensor from the measured values recorded during scanning , the calibration data being the position of the center point of a stylus ball or a sensing disk of the tactile sensor in the machine coordinate system and / or the radius of a stylus ball or a sensing disk.

Further procedures are, for example, from CN 103822603 , EP 2 447 665 , WO 030308375 and WO 2005/090900 known.

Such methods lead to a high expenditure of time during the calibration. This can be justifiable for calibrations of individual tactile sensors, but when calibrating swivel loads, such procedures can be conspicuous and unacceptably long.

Object of the invention

It would therefore be desirable to provide a method, a computer program and a coordinate measuring machine which at least largely avoid the disadvantages of known methods and devices. In particular, a determination of coefficients describing a tactile sensor should be significantly reduced in terms of time.

General description of the invention

This task is addressed by a method, a computer program and a coordinate measuring machine with the features of the independent claims. Advantageous developments, which can be implemented individually or in any combination, are presented in the dependent claims.

In the following, the terms “have”, “have”, “comprise” or “include” or any grammatical deviations therefrom are used in a non-exclusive manner. Accordingly, these terms can relate both to situations in which, besides the features introduced by these terms, no further features are present, or to situations in which one or more further features are present. For example, the expression “A has B”, “A has B”, “A comprises B” or “A includes B” can refer to the situation in which, apart from B, no further element is present in A (ie on a situation in which A consists exclusively of B), as well as on the situation in which, in addition to B, one or more further elements are present in A, for example element C, elements C and D or even further elements .

It is also pointed out that the terms “at least one” and “one or more” as well as grammatical modifications of these terms, if they are used in connection with one or more elements or features and are intended to express that the element or feature is provided once or several times can be used, as a rule, only once, for example when the feature or element is introduced for the first time. If the feature or element is subsequently mentioned again, the corresponding term “at least one” or “one or more” is generally no longer used, without restricting the possibility that the feature or element can be provided once or several times.

Furthermore, the terms “preferably”, “in particular”, “for example” or similar terms are used below in connection with optional features, without this limiting alternative embodiments. Features introduced by these terms are optional features, and it is not intended to use these features to restrict the scope of protection of the claims and in particular of the independent claims. Thus, as the person skilled in the art will recognize, the invention can also be carried out using other configurations. In a similar way, features which are introduced by “in an embodiment of the invention” or by “in an exemplary embodiment of the invention” are understood as optional features, without this being intended to limit alternative configurations or the scope of protection of the independent claims. Furthermore, by means of these introductory expressions, all possibilities of combining the features introduced thereby with other features, be it optional or non-optional features, remain untouched.

In a first aspect, a method for calibrating a tactile sensor with at least one probe body is proposed. The method steps can be carried out in the specified order, with one or more of the steps also being able to be carried out at least partially simultaneously and with one or more of the steps being able to be repeated several times. Furthermore, further steps can additionally be carried out regardless of whether they are mentioned in the present application or not.

The term “tactile sensor”, also referred to as a pushbutton or measuring probe, as it is used here, is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can, without limitation, relate in particular to a sensor which is set up to tactilely scan a measurement object. The term “probe body” as it is used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to an element of the tactile sensor which is set up to interact with a surface to be touched. The probe body can be set up to mechanically touch a measurement object. For example, the probe body can touch a surface of the measurement object, for example by bringing the surfaces into contact, which is referred to as probing or scanning. When there is an interaction, the sensor surface and the surface of the measurement object can touch. In the context of the present invention, a “measurement object” can be any object to be measured, for example a calibration body or a workpiece.

The probe body can in principle have any geometry. The probe body can preferably be a probe ball. For example, the probe body can be made of ruby, in particular the probe ball can be a ruby ball. Alternatively, other configurations can also be conceivable. For example, the stylus ball can be made of hard metal or silicon nitride.

The tactile sensor can be a switching tactile sensor or a measuring tactile sensor. The tactile sensor can be set up as a result of the interaction of the probe body with the To generate at least one signal. The signal can trigger a measurement. A measured value can have information about a contact point. In the context of the present invention, a “touch point” can be understood to mean a point or a location at which the probe body touched the measurement object. In particular, the touch point can be a point of contact. The tactile sensor can have a coordinate system. The coordinate system of the tactile sensor can be, for example, a Cartesian coordinate system or a spherical coordinate system. Other coordinate systems are also conceivable. An origin or zero point of the coordinate system can be in a center, for example a ball center point in the case of a probe ball as the probe body. The contact point can be a point in the coordinate system of the tactile sensor.

In the context of the present invention, a “signal” can be understood to mean any signal that is generated by the tactile sensor as a result of interacting with the measurement object and / or which is generated in response to interacting with the measurement object is produced. The signal can be, for example, an electrical signal, a current signal or a voltage signal. The signal can in particular be generated by an additional sensor system, which is connected to the probe body, for example. The probe body can be attached to a transmission element, for example to a cylindrical shaft. The transmission element can be connected to a probe head via a multi-axis bearing. The probe head can be set up to generate the at least one signal as a result of the interaction between the probe body and the measurement object.

The term “calibration”, as used here, is a broad term which is to be given its usual and common meaning as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to measuring the tactile sensor and / or determining key figures of the tactile sensor. The calibration can in particular include a determination of a tactile vector, at least one characteristic, geometric variable of the probing body, a static compliance of the tactile sensor and a dynamic compliance of the tactile sensor. The tactile sensor can be calibrated on a calibration body. The term “calibration body”, as used here, is a broad term to which its customary and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can refer, without limitation, in particular to a measurement object whose geometry, for example shape and / or size and / or surface properties, and / or position, is known, in particular known with a high degree of accuracy. The calibration body can be a calibration ball with a known radius. The calibration body can, for example, be a highly accurate spherical standard, deviations from a spherical shape smaller than 0.2 μm being possible. The calibration body can be arranged at a known position.

The term “tactile vector”, as used here, is a broad term to which its customary and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can, without limitation, relate in particular to a vector from the origin or zero point of the coordinate system of the tactile sensor, for example in the case of a probe ball as the probe body from the ball center point to the probe point in the coordinate system of the tactile sensor. The tactile vector can be information and / or include the point at which the contact was made with respect to a reference point. Alternatively or additionally, the touch vector can be and / or include information about the vector of any tactile sensor, or its sphere center point, with respect to the sphere center point of the so-called reference probe.

The term “characteristic, geometric size of the probe body” as used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to a shape and / or extension of the probe body, in particular to a radius of the probe ball. Knowledge of the probe ball radius may be necessary in order to calculate backwards from the known center point of the probe body to the point of contact of the probe body and the measurement object or to correct a measured value by the probe ball radius.

The term “static compliance of the tactile sensor” as used here is a broad term which is to be given its usual and common meaning as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to a translational and rotational deformation of the tactile sensor due to the forces and / or torques introduced, such as those that occur when the object to be measured is touched.

The term “dynamic compliance of the tactile sensor” as used here is a broad term which is to be given its usual and common meaning as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to a translational and rotational deformation of the tactile sensor due to linear and / or rotational accelerations, such as occur in particular when the measurement object is scanned.

1. a) Erzeugen mindestens eines Datensatzes, wobei das Erzeugen ein Abtasten des Kalibrierkörpers umfasst, wobei der Antastkörper entlang mindestens einer Trajektorie entlang einer Oberfläche des Kalibrierkörpers bewegt wird und eine Mehrzahl von Messwerten aufgenommen wird, wobei beim Abtasten Geschwindigkeit und Antastkraft des taktilen Sensors variiert werden,
2. b) Auswerten des Datensatzes, wobei das Auswerten des Datensatzes ein Bestimmen des Tastvektors, der mindestens einen charakteristischen, geometrischen Größe des Antastkörpers, der statischen Nachgiebigkeit des taktilen Sensors und der dynamischen Nachgiebigkeit des taktilen Sensors umfasst.

The procedure consists of the following steps:

1. a) generating at least one data set, the generating comprising scanning the calibration body, the probe body being moved along at least one trajectory along a surface of the calibration body and a plurality of measured values being recorded, the speed and probing force of the tactile sensor being varied during scanning,
2. b) evaluating the data record, wherein the evaluation of the data record includes determining the tactile vector, the at least one characteristic, geometric variable of the probe body, the static compliance of the tactile sensor and the dynamic compliance of the tactile sensor.

The term “data set” as used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can, without limitation, relate in particular to a plurality of recorded measured values.

Step a) can in particular include scanning, also called scanning, of the surface of the calibration body. The term “scanning of the surface of the calibration body” as used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to a continuous, touching movement of the tactile sensor along the surface of the calibration body. Measured values can be recorded continuously or discontinuously during the scanning process. The term “trajectory” as used here is a broad term to which its customary and common meaning is to be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to a path and / or a path and / or a path of the tactile sensor, along which the tactile sensor moves. A trajectory can consist of the coordinates of points on the spherical surface. These points can describe any lines on the surface or simple arcs. It can be a continuous line or several individual lines. The control of the coordinate measuring machine can contain these points, for example in a data memory, and can approach them one after the other. Each point of this line or lines can expediently transfer the radial direction as the normal direction before the transfer to the control. This allows the control to adjust the measuring force to the specified level and direction.

The term “contact force”, also referred to as measuring force, as it is used here, is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can, without limitation, refer in particular to a radial force. The term “varying the speed and the probing force”, as used here, is a broad term to which its customary and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can, without limitation, relate in particular to changing the speed and the contact force. For example, the calibration body can be scanned at different speeds, which results in a variation of the effective acceleration. The variation can take place at predetermined times, for example using a test or measurement protocol. The measuring force can be regulated by actuators, for example force coils. Tactile measuring probes without such actuators usually contain spring kinematics. The spring characteristics are known or can simply be viewed as linear in the work area. With these probes, the measuring force can thus be regulated indirectly via the deflection. This is to be regarded as equivalent here and in the following. The speed can be varied in such a way that acceleration vectors result which cover the permissible range as evenly as possible in terms of magnitude and direction. The force can also be varied. If, for example, a maximum measuring force of 1 N and a minimum of 0.2 N is permissible, the calibration measurement can be carried out with 0.2 N, 0.6 N and 1 N, for example. With a hemispherical scanning area, for example, force vectors result in all relevant ones Directions with small, medium and large measuring force. Other measuring forces and variations are also possible. Force and speed can also be varied while scanning a line.

The term “evaluation of the data set” as used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can, without limitation, relate in particular to determining key figures of the tactile sensor from the measured values. The determination of the probe vector, the characteristic, geometric size of the probe body, the static compliance and the dynamic compliance can in particular take place at the same time. “Simultaneously” can be understood to mean that the key figures probe vector, characteristic, geometric size of the probe body, static compliance and dynamic compliance are carried out by recording and evaluating a single data set. In comparison to known two-stage methods, in which first the stylus ball radius, stylus vector and static compliance of the tactile sensor with individual points, or with a scan at slow speed, and then a scanning and determination of the dynamic compliance of the tactile sensor is determined, the time for determining the the coefficients describing the tactile sensor can be significantly reduced.

aus den aufgenommenen Messwerten $\overrightarrow{P_{raw}}$

umfassen, wobei sich die korrigierten Messwerte sich folgendermaßen zusammensetzen: $$\overrightarrow{P_{kor}}=\overrightarrow{P_{raw}}+M_{stat}\overrightarrow{F}+M_{dyn}\overrightarrow{a},$$

wobei $\overrightarrow{F}$

die Antastkraft und $\overrightarrow{a}$

die Beschleunigung des taktilen Sensors sind und die Matrix M_stat Koeffizienten der statischen Nachgiebigkeit und die Matrix M_dyn Koeffizienten der dynamischen Nachgiebigkeit umfassen. In Vektor- bzw. Matrixschreibweise können die korrigierten Messwerte $\overrightarrow{P_{kor}}=\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]$

geschrieben werden als $$\begin{array}{l}\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]=\overrightarrow{P_{raw}}+\left[\begin{array}{ccc}{M}_{stat\mathrm{,11}}& M_{stat\mathrm{,12}}& M_{stat\mathrm{,13}}\\ M_{stat\mathrm{,21}}& M_{stat\mathrm{,22}}& M_{stat\mathrm{,23}}\\ M_{stat\mathrm{,31}}& M_{stat\mathrm{,32}}& M_{stat\mathrm{,33}}\end{array}\right]\overrightarrow{F}+\left[\begin{array}{ccc}{M}_{dyn\mathrm{,11}}& M_{dyn\mathrm{,12}}& M_{dyn\mathrm{,13}}\\ M_{dyn\mathrm{,21}}& M_{dyn\mathrm{,22}}& M_{dyn\mathrm{,23}}\\ M_{dyn\mathrm{,31}}& M_{dyn\mathrm{,32}}& M_{dyn\mathrm{,33}}\end{array}\right]\overrightarrow{a}\\ =\left[\begin{array}{c}{P}_{rawx,i}\\ P_{rawy,i}\\ P_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_z}\end{array}\right]\left[\begin{array}{c}{F}_{x,i}\\ F_{y,i}\\ F_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right],\end{array}$$

wobei M_statt,11...M_statt,33 zu ermittelnde Koeffizienten der statischen Nachgiebigkeit, F_x...z,i bekannte, vektorielle Antastkräfte des i-ten Antastpunkts, M_dyn,11...M_dyn,33 zu ermittelnde Koeffizienten der dynamischen Nachgiebigkeit und a_x...z,i bekannte, vektorielle Beschleunigungen des i-ten Antastpunkts sind. Die Antastkräfte und Beschleunigungen können gemessen werden und/oder können, beispielsweise von einer Steuerung, vorbestimmt sein.The evaluation can include determining corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}$

from the recorded measured values $\overrightarrow{{\mathrm{P.}}_{raw}}$

The corrected measured values are composed as follows: $$\overrightarrow{{\mathrm{P.}}_{kOr}}=\overrightarrow{{\mathrm{P.}}_{raw}}+{\mathrm{M.}}_{stat}\overrightarrow{\mathrm{F.}}+{\mathrm{M.}}_{dyn}\overrightarrow{a},$$

in which $\overrightarrow{\mathrm{F.}}$

the contact force and $\overrightarrow{a}$

are the acceleration of the tactile sensor and the matrix M _stat comprises coefficients of static compliance and the matrix M _dyn comprises coefficients of dynamic compliance. The corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}=\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]$

be written as $$\begin{array}{l}\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]=\overrightarrow{{\mathrm{P.}}_{raw}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{stat\mathrm{,\; 11}}& {\mathrm{M.}}_{stat\mathrm{,\; 12}}& {\mathrm{M.}}_{stat\mathrm{,\; 13}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 21}}& {\mathrm{M.}}_{stat\mathrm{,\; 22}}& {\mathrm{M.}}_{stat\mathrm{,\; 23}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 31}}& {\mathrm{M.}}_{stat\mathrm{,\; 32}}& {\mathrm{M.}}_{stat\mathrm{,\; 33}}\end{array}\right]\overrightarrow{\mathrm{F.}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{dyn\mathrm{,\; 11}}& {\mathrm{M.}}_{dyn\mathrm{,\; 12}}& {\mathrm{M.}}_{dyn\mathrm{,\; 13}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 21}}& {\mathrm{M.}}_{dyn\mathrm{,\; 22}}& {\mathrm{M.}}_{dyn\mathrm{,\; 23}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 31}}& {\mathrm{M.}}_{dyn\mathrm{,\; 32}}& {\mathrm{M.}}_{dyn\mathrm{,\; 33}}\end{array}\right]\overrightarrow{a}\\ =\left[\begin{array}{c}{\mathrm{P.}}_{rawx,i}\\ {\mathrm{P.}}_{rawy,i}\\ {\mathrm{P.}}_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_z}\end{array}\right]\left[\begin{array}{c}{\mathrm{F.}}_{x,i}\\ {\mathrm{F.}}_{y,i}\\ {\mathrm{F.}}_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right],\end{array}$$

where M _{instead of, 11} ... M _{instead of, 33} coefficients of the static flexibility to be determined, F _{x ... z, i} known vectorial probing forces of the i-th probing point, M _{dyn, 11} ... M _{dyn, 33} to be determined Coefficients of dynamic compliance and a _{x ... z, i are} known vector accelerations of the i-th touch point. The contact forces and accelerations can be measured and / or can be predetermined, for example by a controller.

wobei P_x...z,i um die zu ermittelnden statischen und dynamischen Verbiegungen korrigierten Messpunkte, TV_x...z der zu bestimmende Tastvektor, R_TK ein zu bestimmender Radius des Antastkörpers, R_KK ein bekannter Radius des Kalibrierkörpers ist.The evaluation can include solving the following minimization problem: $$min\Vert \sqrt{{\left({\mathrm{P.}}_{x,i}-T{V}_x\right)}^2+{\left({\mathrm{P.}}_{y,i}-T{V}_y\right)}^2{\left({\mathrm{P.}}_{z,i}-T{V}_z\right)}^2}-\left({\mathrm{R.}}_{TK}+{\mathrm{R.}}_{KK}\right)\Vert ,$$

where P _{x ... z, i} measuring points corrected for the static and dynamic deflections to be determined, TV _{x ... z is} the probe vector to be determined, R _{TK is} a radius of the probe body to be determined, R _{KK is} a known radius of the calibration body.

Gleichzeitig gilt Kugelbedingung (1). Radienfehler sind zu minimieren. Das Ergebnis der Korrekturfunktion kann als Eingangsgröße Px,i...z,i in der Kugelfunktion verwendet werden. Das Optimum ist dann gefunden, wenn man die 9 Koeffizienten der ersten 3x3 Matrix zur Korrektur der statischen Verformung, die 9 Koeffizienten der zweiten 3x3 Matrix zur Korrektur der quasi-statischen Verformung bei angenommener konstanter Beschleunigung, die 3 Komponenten des Tastvektors sowie den Radius der Tastkugel so bestimmt hat, dass die Radienfehler nicht weiter verkleinert werden können, im besten Fall also Null werden. Es können dabei auch Freiheitsgrade gesperrt und die entsprechenden Parameter durch Vorgabewerte oder Zwangsbedingungen ersetzt werden. So können die 3x3 Matrizen auch mit jeweils 6 Freiheitsgraden berechnet werden, wenn man symmetrische Matrizen definiert. Gleichzeitig oder alternativ kann der Radius der Tastkugel aus einer vorgelagerten Kalibriermessung, also zum Beispiel aus einem mitgelieferten Kalibrierschein, bekannt sein. Entsprechend kann sich also die Zahl der Freiheitsgrade verringern.The resulting system of linear equations with 4 + 9 + 9 = 22 unknowns can be solved with a corresponding permutation of the speed and contact force and a correspondingly high number of recorded measured values. The optimization calculation is based on the "correction function" shown above $\overrightarrow{{\mathrm{P.}}_{kOr}}.$

At the same time, spherical condition (1) applies. Radius errors are to be minimized. The result of the correction function can be used as input variable Px, i ... z, i in the spherical function. The optimum is found when the 9 coefficients of the first 3x3 matrix for correcting the static deformation, the 9 coefficients of the second 3x3 matrix for correcting the quasi-static deformation with assumed constant acceleration, the 3 components of the probe vector and the radius of the probe ball has determined in such a way that the radius errors cannot be further reduced, in the best case they become zero. Degrees of freedom can also be blocked and the corresponding parameters replaced by default values or constraints. The 3x3 matrices can also be calculated with 6 degrees of freedom each if you define symmetrical matrices. At the same time or alternatively, the radius of the probe ball can be known from an upstream calibration measurement, for example from a calibration certificate supplied. Accordingly, the number of degrees of freedom can be reduced.

When solving the optimization problem, there is always a residual in the real case. This can result, for example, from the fact that the spring characteristics or the measuring force actuators are not linear. These residuals can be assigned to the states, in particular force and acceleration, using known methods and expediently processed, for example with a low pass, filtered, and stored in error tables. Using known methods, these error tables can be saved, transferred, and used for correction during later measurements in the same way as the matrices for correcting the linear effects, in accordance with the current states. The error tables can include a multidimensional matrix in which each dimension corresponds to a component of the force vector and the acceleration vector. The residual errors can also be saved in a space-saving manner with polynomials, splines or transformed into the frequency space and used accordingly for correction. This is also referred to as an error table in the context of the present invention, the term correction table or the usual English term “error map” are also to be regarded as synonymous here. It must be ensured that only the reproducible proportion of these residual errors are used as correction values. This can be achieved by repeated calibration measurements. The residuals can also be used to determine the measurement uncertainty. If a correction table is used, only the non-reproducible portion is used to determine the measurement uncertainty. For this purpose, these residual errors are saved in error tables, as well as for correction, and are used when measuring according to the current conditions to describe the current measurement uncertainty contribution of the tactile sensor used. This measurement uncertainty information can be used as a contribution to the total measurement uncertainty of the measurement system in accordance with the usual procedures.

In Vektor- bzw. Matrixschreibweise können die korrigierten Messwerte $\overrightarrow{P_{kor}}=\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]$

geschrieben werden als $$\begin{array}{l}\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]=\overrightarrow{P_{raw}}+\left[\begin{array}{ccc}{M}_{stat\mathrm{,11}}& M_{stat\mathrm{,12}}& M_{stat\mathrm{,13}}\\ M_{stat\mathrm{,21}}& M_{stat\mathrm{,22}}& M_{stat\mathrm{,23}}\\ M_{stat\mathrm{,31}}& M_{stat\mathrm{,32}}& M_{stat\mathrm{,33}}\end{array}\right]\overrightarrow{F}+\left[\begin{array}{ccc}{M}_{dyn\mathrm{,11}}& M_{dyn\mathrm{,12}}& M_{dyn\mathrm{,13}}\\ M_{dyn\mathrm{,21}}& M_{dyn\mathrm{,22}}& M_{dyn\mathrm{,23}}\\ M_{dyn\mathrm{,31}}& M_{dyn\mathrm{,32}}& M_{dyn\mathrm{,33}}\end{array}\right]\overrightarrow{a}\\ +\left[\begin{array}{ccc}{M}_{ruck\mathrm{,11}}& M_{ruck\mathrm{,12}}& M_{ruck\mathrm{,13}}\\ M_{ruck\mathrm{,21}}& M_{ruck\mathrm{,22}}& M_{ruck\mathrm{,23}}\\ M_{ruck\mathrm{,31}}& M_{ruck\mathrm{,32}}& M_{ruck\mathrm{,33}}\end{array}\right]\overrightarrow{\dot{a}}+\left[\begin{array}{c}{V}_{temp,x}\\ V_{temp,y}\\ V_{temp,z}\end{array}\right]T\\ \\ =\left[\begin{array}{c}{P}_{rawx,i}\\ P_{rawy,i}\\ P_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_z}\end{array}\right]\left[\begin{array}{c}{F}_{x,i}\\ F_{y,i}\\ F_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_z}\end{array}\right]\left[\begin{array}{c}{\dot{a}}_{x,i}\\ {\dot{a}}_{y,i}\\ {\dot{a}}_{z,i}\end{array}\right]+\\ \left[\begin{array}{c}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }T}\end{array}\right]T,\end{array}$$

wobei M_ruck,11...M_ruck,33 zu ermittelnde Koeffizienten des Effektes „Verbiegung durch Ruck“, a_x...z,i bekannte Änderungen der Beschleunigungen des i-ten Antastpunkts, T bekannte Temperaturwerte, und V_temp,x...z zu ermittelnde vektorielle Einflüsse durch die Temperatur sind. Die Änderung der Beschleunigung und Temperatur können gemessen werden und/oder können, beispielsweise von einer Steuerung, vorbestimmt sein.The method can include calibration for at least one further influencing variable. The term “influencing variable” as it is used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can refer, without limitation, in particular to any physical quantity that has an influence on the measurement and thus the measured value. The further influencing variable can be, for example, a temperature or a change in the acceleration, also referred to as a jerk. However, other influencing variables are also conceivable. The further influencing variable can be varied in step a). The further influencing variable can be taken into account in step b). The linear system of equations can be offset by effects such as "bending due to jerk" and / or influences due to temperature: $$\overrightarrow{{\mathrm{P.}}_{kOr}}=\overrightarrow{{\mathrm{P.}}_{raw}}+{\mathrm{M.}}_{stat}\overrightarrow{\mathrm{F.}}+{\mathrm{M.}}_{dyn}\overrightarrow{a}+{\mathrm{M.}}_{ruck}\overrightarrow{\dot{a}}+\overrightarrow{V_{temp}}T.$$

The corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}=\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]$

be written as $$\begin{array}{l}\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]=\overrightarrow{{\mathrm{P.}}_{raw}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{stat\mathrm{,\; 11}}& {\mathrm{M.}}_{stat\mathrm{,\; 12}}& {\mathrm{M.}}_{stat\mathrm{,\; 13}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 21}}& {\mathrm{M.}}_{stat\mathrm{,\; 22}}& {\mathrm{M.}}_{stat\mathrm{,\; 23}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 31}}& {\mathrm{M.}}_{stat\mathrm{,\; 32}}& {\mathrm{M.}}_{stat\mathrm{,\; 33}}\end{array}\right]\overrightarrow{\mathrm{F.}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{dyn\mathrm{,\; 11}}& {\mathrm{M.}}_{dyn\mathrm{,\; 12}}& {\mathrm{M.}}_{dyn\mathrm{,\; 13}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 21}}& {\mathrm{M.}}_{dyn\mathrm{,\; 22}}& {\mathrm{M.}}_{dyn\mathrm{,\; 23}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 31}}& {\mathrm{M.}}_{dyn\mathrm{,\; 32}}& {\mathrm{M.}}_{dyn\mathrm{,\; 33}}\end{array}\right]\overrightarrow{a}\\ +\left[\begin{array}{ccc}{\mathrm{M.}}_{ruck\mathrm{,\; 11}}& {\mathrm{M.}}_{ruck\mathrm{,\; 12}}& {\mathrm{M.}}_{ruck\mathrm{,\; 13}}\\ {\mathrm{M.}}_{ruck\mathrm{,\; 21}}& {\mathrm{M.}}_{ruck\mathrm{,\; 22}}& {\mathrm{M.}}_{ruck\mathrm{,\; 23}}\\ {\mathrm{M.}}_{ruck\mathrm{,\; 31}}& {\mathrm{M.}}_{ruck\mathrm{,\; 32}}& {\mathrm{M.}}_{ruck\mathrm{,\; 33}}\end{array}\right]\overrightarrow{\dot{a}}+\left[\begin{array}{c}{V}_{temp,x}\\ V_{temp,y}\\ V_{temp,z}\end{array}\right]T\\ \\ =\left[\begin{array}{c}{\mathrm{P.}}_{rawx,i}\\ {\mathrm{P.}}_{rawy,i}\\ {\mathrm{P.}}_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_z}\end{array}\right]\left[\begin{array}{c}{\mathrm{F.}}_{x,i}\\ {\mathrm{F.}}_{y,i}\\ {\mathrm{F.}}_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_z}\end{array}\right]\left[\begin{array}{c}{\dot{a}}_{x,i}\\ {\dot{a}}_{y,i}\\ {\dot{a}}_{z,i}\end{array}\right]+\\ \left[\begin{array}{c}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }T}\end{array}\right]T,\end{array}$$

where M _{ruck, 11} ... M _{ruck, 33} coefficients to be determined for the “bending by jerk” effect, a _{x ... z, i} known changes in the accelerations of the i-th touch point, T known temperature _{values, and V temp, x ... z} are vectorial influences to be determined by the temperature. The change in acceleration and temperature can be measured and / or can be predetermined, for example by a controller.

Furthermore, within the scope of the present invention, a computer program is proposed which, when running on a computer or computer network, executes the method according to the invention in one of its configurations.

Furthermore, within the scope of the present invention, a computer program with program code means is proposed in order to carry out the method according to the invention in one of its configurations when the program is executed on a computer or computer network. In particular, the program code means can be stored on a computer-readable data carrier and / or a computer-readable storage medium.

The terms “computer-readable data carrier” and “computer-readable storage medium”, as used here, can in particular refer to non-transitory data storage media, for example a hardware data storage medium on which computer-executable instructions are stored. The computer-readable data carrier or the computer-readable storage medium can in particular be or comprise a storage medium such as a random access memory (RAM) and / or a read-only memory (ROM).

In addition, within the scope of the present invention, a data carrier is proposed on which a data structure is stored which, after being loaded into a working and / or main memory of a computer or computer network, can execute the method according to the invention in one of its configurations.

In the context of the present invention, a computer program product with program code means stored on a machine-readable carrier is also proposed in order to carry out the method according to the invention in one of its configurations when the program is executed on a computer or computer network.

A computer program product is understood to mean the program as a tradable product. It can basically be in any form, for example on paper or a computer-readable data carrier, and can in particular be distributed via a data transmission network.

Finally, within the scope of the present invention, a modulated data signal is proposed which contains instructions that can be executed by a computer system or computer network for executing a method according to one of the described embodiments.

With regard to the computer-implemented aspects of the invention, one, several or even all method steps of the method according to one or more of the embodiments proposed here can be carried out by means of a computer or computer network. Thus, in general, any of the method steps, including the provision and / or manipulation of data, can be carried out by means of a computer or computer network. In general, these steps can comprise any of the method steps, with the exception of the steps which require manual work, for example the provision of measurement objects and / or certain aspects of performing actual measurements.

In a further aspect, a coordinate measuring machine for measuring at least one workpiece is proposed within the scope of the present invention.

The term “workpiece” as used here is a broad term which is to be given its usual and common meaning as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can in particular refer to any object without restriction. The workpiece, in particular a surface of the workpiece, can have strong curvatures, i.e. small radii up to sharp edges. The workpiece can be a freeform surface. For example, the workpiece can be a turbine blade on a blade wheel. However, other workpieces are also conceivable.

The term “coordinate measuring machine” as used here is a broad term to which its usual and common meaning should be assigned, as understood by the person skilled in the art. The term is not limited to any specific or adapted meaning. The term can relate, without limitation, in particular to a device for determining at least one coordinate of the workpiece. The coordinate measuring machine can be a portal measuring machine or a bridge measuring machine. The coordinate measuring machine can have a measuring table for supporting at least one workpiece to be measured. The coordinate measuring machine can have at least one portal which has at least one first vertical column, at least one second vertical column and a cross member connecting the first vertical column and the second vertical column. At least one vertical column selected from the first and second vertical columns can be movably supported on the measuring table. The horizontal direction can be a direction along a y-axis. The coordinate measuring machine can have a coordinate system, for example a Cartesian coordinate system or a spherical coordinate system. Other coordinate systems are also conceivable. An origin or zero point of the coordinate system can be given, for example, by a sensor of the coordinate measuring device, in particular the tactile sensor according to the invention. An x-axis can run perpendicular to the y-axis, in a plane of the support surface of the measuring table. A z-axis, also called a longitudinal axis, can extend perpendicular to the plane of the support surface, in a vertical direction. The vertical columns can extend along the z-axis. The traverse can extend along the x-axis. The coordinate measuring machine can have at least one measuring slide which is movably mounted along the cross member. A “measuring slide” can generally be understood to mean a slide which is set up to receive at least one sensor device directly or by means of further components. A quill movable in a vertical direction, for example along the z-axis, can be mounted in the measuring slide. The tactile sensor, for example, can be arranged at a lower end of the quill, in particular an end pointing in the direction of the support surface. The coordinate measuring machine has the at least one tactile sensor with the at least one probe body. The tactile sensor can be interchangeably connected to the coordinate measuring machine. The coordinate measuring machine has at least one calibration body.

With regard to the definitions and configuration of the components of the coordinate measuring machine such as the tactile sensor and calibration body, reference can be made to the description of the method according to the invention.

The coordinate measuring machine has at least one controller. The controller is set up to move the probe body along at least one trajectory along a surface of the calibration body and to record a plurality of measured values. The control is set up to vary the speed and contact force of the tactile sensor when scanning.

The controller can comprise at least one data processing device, for example at least one computer or microcontroller. The data processing device can have one or more volatile and / or non-volatile data memories, wherein the data processing device can be set up in terms of programming, for example, to control the tactile sensor. The controller can furthermore comprise at least one interface, for example an electronic interface and / or a man-machine interface such as an input / output device such as a display and / or a keyboard. For example, one or more electronic connections can be provided between the tactile sensor and the controller. The control can, for example, be set up centrally or also decentrally. Other configurations are also conceivable.

The coordinate measuring machine has at least one evaluation unit which is set up to evaluate the recorded measured values. The evaluation includes determining a tactile vector, at least one characteristic, geometric variable of the probing body, a static compliance of the tactile sensor and a dynamic compliance of the tactile sensor. The evaluation unit can for example comprise at least one data processing device, for example at least one computer or microcontroller. The data processing device can have one or more volatile and / or non-volatile data memories, wherein the data processing device can be set up, for example, in terms of programming, in order to carry out the one evaluation. The evaluation unit can be part of the control system.

• Ausführungsform 1: Verfahren zum Kalibrieren eines taktilen Sensors mit mindestens einem Antastkörper, wobei das Verfahren die folgenden Schritte aufweist:
  1. a) Erzeugen mindestens eines Datensatzes, wobei das Erzeugen ein Abtasten eines Kalibrierkörpers umfasst, wobei der Antastkörper entlang mindestens einer Trajektorie entlang einer Oberfläche des Kalibrierkörpers bewegt wird und eine Mehrzahl von Messwerten aufgenommen wird, wobei beim Abtasten Geschwindigkeit und Antastkraft des taktilen Sensors variiert werden,
  2. b) Auswerten des Datensatzes, wobei das Auswerten des Datensatzes ein Bestimmen eines Tastvektors, mindestens einer charakteristischen, geometrischen Größe des Antastkörpers, einer statischen Nachgiebigkeit des taktilen Sensors und einer dynamischen Nachgiebigkeit des taktilen Sensors umfasst.
• Ausführungsform 2: Verfahren nach der vorhergehenden Ausführungsform, wobei das Bestimmen des Tastvektors, der charakteristischen, geometrischen Größe des Antastkörpers, der statischen Nachgiebigkeit und der dynamischen Nachgiebigkeit gleichzeitig erfolgt.
• Ausführungsform 3: Verfahren nach einer der vorhergehenden Ausführungsformen, wobei der Kalibrierkörper eine Kalibrierkugel mit bekanntem Radius ist.
• Ausführungsform 4: Verfahren nach einer der vorhergehenden Ausführungsformen, wobei der Antastkörper eine Tastkugel ist.
• Ausführungsform 5: Verfahren nach der vorhergehenden Ausführungsform, wobei die charakteristische, geometrische Größe des Antastkörpers ein Tastkugelradius ist.
• Ausführungsform 6: Verfahren nach einer der vorhergehenden Ausführungsformen, wobei das Auswerten ein Bestimmen von korrigierten Messwerten $\overrightarrow{P_{kor}}$
  
  aus den aufgenommenen Messwerten $\overrightarrow{P_{raw}}$
  
  umfasst, wobei $\overrightarrow{P_{kor}}=\overrightarrow{P_{raw}}+M_{stat}\overrightarrow{F}+M_{dyn}\overrightarrow{a},$
  
  wobei $\overrightarrow{F}$
  
  die Antastkraft und $\overrightarrow{a}$
  
  die Beschleunigung des taktilen Sensors sind und die Matrix M_stat Koeffizienten der statischen Nachgiebigkeit und die Matrix M_dyn Koeffizienten der dynamischen Nachgiebigkeit umfassen.
• Ausführungsform 7: Verfahren nach einer der vorhergehenden Ausführungsformen, wobei das Auswerten ein Lösen des folgenden Minimierungsproblems umfasst: $$min\Vert \sqrt{{\left(P_{x,i}-T{V}_x\right)}^2+{\left(P_{y,i}-T{V}_y\right)}^2{\left(P_{z,i}-T{V}_z\right)}^2}-\left(R_{TK}+R_{KK}\right)\Vert ,$$
  
  wobei P_x...z,i um die zu ermittelnden statischen und dynamischen Verbiegungen korrigierten Messpunkte, TV_x...z der zu bestimmende Tastvektor, R_TK ein zu bestimmender Radius des Antastkörpers, R_KK ein bekannter Radius des Kalibrierkörpers ist.
• Ausführungsform 8: Verfahren nach einer der vorhergehenden Ausführungsformen, wobei das Verfahren ein Kalibrieren auf mindestens eine weitere Einflussgröße umfasst, wobei in Schritt a) die weitere Einflussgröße variiert wird, wobei in Schritt b) die weitere Einflussgröße berücksichtigt wird, wobei die weitere Einflussgröße eine Temperatur oder eine Änderung der Beschleunigung ist.
• Ausführungsform 9: Computerprogramm, welches bei Ablauf auf einem Computer oder Computer-Netzwerk das Verfahren nach einer der vorhergehenden Ausführungsformen ausführt.
• Ausführungsform 10: Koordinatenmessgerät zum Vermessen mindestens eines Werkstücks, wobei das Koordinatenmessgerät mindestens einen taktilen Sensor mit mindestens einem Antastkörper aufweist, wobei das Koordinatenmessgerät mindestens einen Kalibrierkörper aufweist, wobei das Koordinatenmessgerät mindestens eine Steuerung aufweist, wobei die Steuerung eingerichtet ist den Antastkörper entlang mindestens einer Trajektorie entlang einer Oberfläche des Kalibrierkörpers zu bewegen und eine Mehrzahl von Messwerten aufzunehmen, wobei die Steuerung eingerichtet ist beim Abtasten Geschwindigkeit und Antastkraft des taktilen Sensors zu variieren, wobei das Koordinatenmessgerät mindestens eine Auswerteeinheit aufweist, welche eingerichtet ist die aufgenommenen Messwerte auszuwerten, wobei das Auswerten ein Bestimmen eines Tastvektors, mindestens einer charakteristischen, geometrischen Größe des Antastkörpers, einer statischen Nachgiebigkeit des taktilen Sensors und einer dynamischen Nachgiebigkeit des taktilen Sensors umfasst.

In summary, without restricting further possible configurations, the following embodiments are proposed:

• Embodiment 1: A method for calibrating a tactile sensor with at least one probe body, the method comprising the following steps:
  1. a) generating at least one data set, the generating comprising scanning a calibration body, the probe body being moved along at least one trajectory along a surface of the calibration body and a plurality of measured values being recorded, the speed and probing force of the tactile sensor being varied during scanning,
  2. b) evaluating the data record, wherein the evaluation of the data record includes determining a tactile vector, at least one characteristic, geometric variable of the probe body, a static compliance of the tactile sensor and a dynamic compliance of the tactile sensor.
• Embodiment 2: Method according to the preceding embodiment, the determination of the sensing vector, the characteristic, geometric size of the sensing body, the static flexibility and the dynamic flexibility taking place at the same time.
• Embodiment 3: Method according to one of the preceding embodiments, wherein the calibration body is a calibration ball with a known radius.
• Embodiment 4: Method according to one of the preceding embodiments, wherein the probe body is a probe ball.
• Embodiment 5: Method according to the preceding embodiment, the characteristic, geometric size of the probe body being a probe ball radius.
• Embodiment 6: The method according to one of the preceding embodiments, wherein the evaluation includes determining corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}$
  
  from the recorded measured values $\overrightarrow{{\mathrm{P.}}_{raw}}$
  
  includes, where $\overrightarrow{{\mathrm{P.}}_{kOr}}=\overrightarrow{{\mathrm{P.}}_{raw}}+{\mathrm{M.}}_{stat}\overrightarrow{\mathrm{F.}}+{\mathrm{M.}}_{dyn}\overrightarrow{a},$
  
  in which $\overrightarrow{\mathrm{F.}}$
  
  the contact force and $\overrightarrow{a}$
  
  are the acceleration of the tactile sensor and the matrix M _stat comprises coefficients of static compliance and the matrix M _dyn comprises coefficients of dynamic compliance.
• Embodiment 7: The method according to one of the preceding embodiments, wherein the evaluation comprises solving the following minimization problem: $$min\Vert \sqrt{{\left({\mathrm{P.}}_{x,i}-T{V}_x\right)}^2+{\left({\mathrm{P.}}_{y,i}-T{V}_y\right)}^2{\left({\mathrm{P.}}_{z,i}-T{V}_z\right)}^2}-\left({\mathrm{R.}}_{TK}+{\mathrm{R.}}_{KK}\right)\Vert ,$$
  
  where P _{x ... z, i} measuring points corrected for the static and dynamic deflections to be determined, TV _{x ... z is} the probe vector to be determined, R _{TK is} a radius of the probe body to be determined, R _{KK is} a known radius of the calibration body.
• Embodiment 8: Method according to one of the preceding embodiments, wherein the method comprises a calibration for at least one further influencing variable, the further influencing variable being varied in step a), the further influencing variable being taken into account in step b), the further influencing variable being a temperature or a change in acceleration.
• Embodiment 9: Computer program which, when run on a computer or computer network, executes the method according to one of the preceding embodiments.
• Embodiment 10: Coordinate measuring device for measuring at least one workpiece, the coordinate measuring device having at least one tactile sensor with at least one probe body, the coordinate measuring device having at least one calibration body, the coordinate measuring device having at least one controller, the controller being set up the probe body along at least one trajectory to move along a surface of the calibration body and to record a plurality of measured values, the controller being set up to vary the speed and contact force of the tactile sensor during scanning, the coordinate measuring device having at least one evaluation unit which is set up to evaluate the recorded measured values, the evaluation being a Determination of a tactile vector, at least one characteristic, geometric variable of the probing body, a static compliance of the tactile sensor and a dynamic compliance t of the tactile sensor includes.

Brief description of the figures

Further details and features emerge from the following description of exemplary embodiments, in particular in conjunction with the subclaims. The respective features can be implemented individually or in combination with one another. The invention is not restricted to the exemplary embodiments. The exemplary embodiments are shown schematically in the figures. The same reference numbers in the individual figures designate elements that are the same or functionally the same or correspond to one another with regard to their functions.

• 1 ein Ausführungsbeispiel eines erfindungsgemäßen Verfahrens; und
• 2 eine schematische Darstellung eines Ausführungsbeispiels eines erfindungsgemäßen Koordinatenmessgeräts.

Show in detail:

• 1 an embodiment of a method according to the invention; and
• 2 a schematic representation of an embodiment of a coordinate measuring machine according to the invention.

Description of the exemplary embodiments

1 shows an embodiment of a method according to the invention 110 for calibrating a tactile sensor 112 with at least one probe body 114 . The tactile sensor 112 can, as in 2 shown, part of a coordinate measuring machine 116 be. The probe body 114 can be set up to interact with a surface to be touched. The probe body 114 can be set up to mechanically touch a measurement object. For example, the probe body 114 touch a surface of the measurement object, for example by bringing the surfaces into contact, which is referred to as probing or scanning. When there is an interaction, the sensor surface and the surface of the measurement object can touch.

The probe body 114 can basically have any geometry. The probe body can preferably 114 be a probe ball. For example, the probe body 114 be made of ruby, in particular the probe ball can be a ruby ball. Alternatively, other configurations can also be conceivable. For example, the stylus ball can be made of hard metal or silicon nitride.

The tactile sensor 112 can be a switching tactile sensor or a measuring tactile sensor. The tactile sensor 112 can be set up as a result of the interaction of the probe body 114 to generate at least one signal with the measurement object. The signal can trigger a measurement. A measured value can have information about a contact point. In particular, the touch point can be a point of contact. The tactile sensor 112 can be a coordinate system 118 exhibit. The coordinate system 118 can for example be a Cartesian coordinate system or a spherical coordinate system. Other coordinate systems are also conceivable. An origin or zero point of the coordinate system can be in a center, for example in the case of a probe ball as the probe body 114 a center of a sphere. The contact point can be a point in the coordinate system of the tactile sensor 112 be.

The signal can be, for example, an electrical signal, a current signal or a voltage signal. The signal can, in particular, come from an additional sensor system, which for example is connected to the probe body 114 connected, can be generated. The probe body 114 can be attached to a transmission element, for example to a cylindrical shaft. The transmission element can be connected to a probe head via a multi-axis bearing. The probe head can be set up to generate the at least one signal as a result of the interaction between the probe body and the measurement object.

The calibration can include measuring the tactile sensor and / or determining key figures of the tactile sensor 112 include. The calibration can, in particular, be a determination of a probe vector, at least one characteristic, geometric variable of the probe body 114 , a static compliance of the tactile sensor 112 and dynamic compliance of the tactile sensor 112 include. Calibrating the tactile sensor 112 can on a calibration body 120 respectively. The calibration body 120 can be a measurement object whose geometry, for example shape and / or size and / or surface properties, and / or position, is known, in particular known with a high degree of accuracy. The calibration body 120 can be a calibration sphere with a known radius. The calibration body 120 can, for example, be a highly accurate spherical standard, with deviations from a spherical shape smaller than 0.2 µm being possible. The calibration body 120 can be located in a known position.

The probe vector can be a vector from the origin or zero point of the coordinate system 118 of the tactile sensor 112 , for example with a probe ball as the probe body 114 from the center of the sphere to the touch point in the coordinate system of the tactile sensor 112 be. The tactile vector can be information and / or include the point at which the contact was made with respect to a reference point. Alternatively or additionally, the touch vector can be and / or include information about the vector of any tactile sensor, or its sphere center point, with respect to the sphere center point of the so-called reference probe. The characteristic, geometric size of the probe 114 can be a shape and / or extension of the probe body 114 be, in particular on a radius of the stylus ball. Knowledge of the probe ball radius may be necessary in order to be able to touch the known center point of the probe body 114 on the point of contact of the probe 114 and to recalculate the measurement object or to correct a measured value by the stylus ball radius. The static compliance of the tactile sensor 112 can translational and rotational deformation of the tactile sensor 112 due to the forces and / or moments introduced, such as those that occur when the object to be measured is touched. The dynamic compliance of the tactile sensor 112 can translational and rotational deformation of the tactile sensor 112 due to linear and / or rotary accelerations, such as those that occur in particular when the measurement object is scanned.

1. a) Erzeugen mindestens eines Datensatzes (Bezugsziffer 122), wobei das Erzeugen ein Abtasten des Kalibrierkörpers 120 umfasst, wobei der Antastkörper 114 entlang mindestens einer Trajektorie entlang einer Oberfläche des Kalibrierkörpers 120 bewegt wird und eine Mehrzahl von Messwerten aufgenommen wird, wobei beim Abtasten Geschwindigkeit und Antastkraft des taktilen Sensors 114 variiert werden,
2. b) Auswerten des Datensatzes (Bezugsziffer 124), wobei das Auswerten des Datensatzes ein Bestimmen des Tastvektors, der mindestens einen charakteristischen, geometrischen Größe des Antastkörpers, der statischen Nachgiebigkeit des taktilen Sensors 112 und der dynamischen Nachgiebigkeit des taktilen Sensors 112 umfasst.

The procedure 110 has the following steps:

1. a) Generating at least one data record (reference number 122 ), the generating being a scanning of the calibration body 120 comprises, wherein the probe body 114 along at least one trajectory along a surface of the calibration body 120 is moved and a plurality of measured values is recorded, the speed and contact force of the tactile sensor during scanning 114 be varied,
2. b) Evaluation of the data record (reference number 124 ), wherein the evaluation of the data record is a determination of the tactile vector, the at least one characteristic, geometric variable of the probe body, the static flexibility of the tactile sensor 112 and the dynamic compliance of the tactile sensor 112 includes.

The data record can include a plurality of recorded measured values. Step a) can in particular include scanning, also called scanning, of the surface of the calibration body 120 include. The tactile sensor 112 can be continuous and touching the surface of the calibration body 120 be moved along. Measured values can be recorded continuously or discontinuously during the scanning process. The trajectory can be a path and / or a path and / or a path of the tactile sensor, along which the tactile sensor is located 112 emotional. A trajectory can consist of the coordinates of points on the spherical surface. These points can describe any lines on the surface or simple arcs. It can be a continuous line or several individual lines. The control 138 can contain these points, for example in a data memory, and can approach them one after the other. Each point of this line or lines can expediently be transferred to the control system 138 pass the radial direction as normal direction. This enables the controller 138 adjust the measuring force to the specified level and direction.

Varying the speed and the contact force can include changing the speed and the contact force. For example, the calibration body 120 can be scanned at different speeds, which results in a variation of the effective acceleration. The variation can take place at predetermined times, for example using a test or measurement protocol. The contact force can be regulated by actuators, for example power coils. Tactile measuring probes without such actuators usually contain spring kinematics. The spring characteristics are known or can simply be viewed as linear in the work area. With these probes, the measuring force can thus be regulated indirectly via the deflection. This is to be regarded as equivalent here and in the following. The speed can be varied in such a way that acceleration vectors result which cover the permissible range as evenly as possible in terms of magnitude and direction. The force can also be varied. If, for example, a maximum measuring force of 1 N and a minimum of 0.2 N is permissible, the calibration measurement can be carried out with 0.2 N, 0.6 N and 1 N, for example. With hemispherical scanning area, for example, force vectors result in all relevant directions with small, medium and large measuring force. Other measuring forces and variations are also possible. Force and speed can also be varied while scanning a line.

The determination of the probe vector, the characteristic, geometric size of the probe body, the static compliance and the dynamic compliance can in particular take place at the same time. Compared to known two-stage processes, in which first the stylus ball radius, stylus vector and static flexibility of the tactile sensor 112 with single points, or with a scan at slow speed, and then a scan and determination of the dynamic compliance of the tactile sensor 112 is determined, the time for determining the coefficients describing the tactile sensor can be significantly reduced.

aus den aufgenommenen Messwerten $\overrightarrow{P_{raw}}$

umfassen, wobei sich die korrigierten Messwerte sich folgendermaßen zusammensetzen: $$\overrightarrow{P_{kor}}=\overrightarrow{P_{raw}}+M_{stat}\overrightarrow{F}+M_{dyn}\overrightarrow{a},$$

wobei $\overrightarrow{F}$

die Antastkraft und $\overrightarrow{a}$

die Beschleunigung des taktilen Sensors 112 sind und die Matrix M_stat Koeffizienten der statischen Nachgiebigkeit und die Matrix M_dyn Koeffizienten der dynamischen Nachgiebigkeit umfassen. In Vektor- bzw. Matrixschreibweise können die korrigierten Messwerte $\overrightarrow{P_{kor}}=\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]$

geschrieben werden als $$\begin{array}{l}\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]=\overrightarrow{P_{raw}}+\left[\begin{array}{ccc}{M}_{stat\mathrm{,11}}& M_{stat\mathrm{,12}}& M_{stat\mathrm{,13}}\\ M_{stat\mathrm{,21}}& M_{stat\mathrm{,22}}& M_{stat\mathrm{,23}}\\ M_{stat\mathrm{,31}}& M_{stat\mathrm{,32}}& M_{stat\mathrm{,33}}\end{array}\right]\overrightarrow{F}+\left[\begin{array}{ccc}{M}_{dyn\mathrm{,11}}& M_{dyn\mathrm{,12}}& M_{dyn\mathrm{,13}}\\ M_{dyn\mathrm{,21}}& M_{dyn\mathrm{,22}}& M_{dyn\mathrm{,23}}\\ M_{dyn\mathrm{,31}}& M_{dyn\mathrm{,32}}& M_{dyn\mathrm{,33}}\end{array}\right]\overrightarrow{a}\\ =\left[\begin{array}{c}{P}_{rawx,i}\\ P_{rawy,i}\\ P_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_z}\end{array}\right]\left[\begin{array}{c}{F}_{x,i}\\ F_{y,i}\\ F_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right],\end{array}$$

wobei M_statt,11...M_statt,33 zu ermittelnde Koeffizienten der statischen Nachgiebigkeit, F_x...z,i bekannte, vektorielle Antastkräfte des i-ten Antastpunkts, M_dyn,11...M_dyn,33 zu ermittelnde Koeffizienten der dynamischen Nachgiebigkeit und a_x...z,i bekannte, vektorielle Beschleunigungen des i-ten Antastpunkts sind. Die Antastkräfte und Beschleunigungen können gemessen werden und/oder können vorbestimmt sein.The evaluation 124 can determine corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}$

from the recorded measured values $\overrightarrow{{\mathrm{P.}}_{raw}}$

The corrected measured values are composed as follows: $$\overrightarrow{{\mathrm{P.}}_{kOr}}=\overrightarrow{{\mathrm{P.}}_{raw}}+{\mathrm{M.}}_{stat}\overrightarrow{\mathrm{F.}}+{\mathrm{M.}}_{dyn}\overrightarrow{a},$$

in which $\overrightarrow{\mathrm{F.}}$

the contact force and $\overrightarrow{a}$

the acceleration of the tactile sensor 112 and the matrix M _stat comprises coefficients of static compliance and the matrix M _dyn comprises coefficients of dynamic compliance. The corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}=\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]$

be written as $$\begin{array}{l}\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]=\overrightarrow{{\mathrm{P.}}_{raw}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{stat\mathrm{,\; 11}}& {\mathrm{M.}}_{stat\mathrm{,\; 12}}& {\mathrm{M.}}_{stat\mathrm{,\; 13}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 21}}& {\mathrm{M.}}_{stat\mathrm{,\; 22}}& {\mathrm{M.}}_{stat\mathrm{,\; 23}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 31}}& {\mathrm{M.}}_{stat\mathrm{,\; 32}}& {\mathrm{M.}}_{stat\mathrm{,\; 33}}\end{array}\right]\overrightarrow{\mathrm{F.}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{dyn\mathrm{,\; 11}}& {\mathrm{M.}}_{dyn\mathrm{,\; 12}}& {\mathrm{M.}}_{dyn\mathrm{,\; 13}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 21}}& {\mathrm{M.}}_{dyn\mathrm{,\; 22}}& {\mathrm{M.}}_{dyn\mathrm{,\; 23}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 31}}& {\mathrm{M.}}_{dyn\mathrm{,\; 32}}& {\mathrm{M.}}_{dyn\mathrm{,\; 33}}\end{array}\right]\overrightarrow{a}\\ =\left[\begin{array}{c}{\mathrm{P.}}_{rawx,i}\\ {\mathrm{P.}}_{rawy,i}\\ {\mathrm{P.}}_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_z}\end{array}\right]\left[\begin{array}{c}{\mathrm{F.}}_{x,i}\\ {\mathrm{F.}}_{y,i}\\ {\mathrm{F.}}_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right],\end{array}$$

where M _{instead of, 11} ... M _{instead of, 33} coefficients of the static flexibility to be determined, F _{x ... z, i} known vectorial probing forces of the i-th probing point, M _{dyn, 11} ... M _{dyn, 33} to be determined Coefficients of dynamic compliance and a _{x ... z, i are} known vector accelerations of the i-th touch point. The contact forces and accelerations can be measured and / or can be predetermined.

wobei P_x...z,i um die zu ermittelnden statischen und dynamischen Verbiegungen korrigierten Messpunkte, TV_x...z der zu bestimmende Tastvektor, R_TK ein zu bestimmender Radius des Antastkörpers 114, R_KK ein bekannter Radius des Kalibrierkörpers 120 ist.The evaluation can include solving the following minimization problem: $$min\Vert \sqrt{{\left({\mathrm{P.}}_{x,i}-T{V}_x\right)}^2+{\left({\mathrm{P.}}_{y,i}-T{V}_y\right)}^2{\left({\mathrm{P.}}_{z,i}-T{V}_z\right)}^2}-\left({\mathrm{R.}}_{TK}+{\mathrm{R.}}_{KK}\right)\Vert ,$$

where P _{x ... z, i} measuring points corrected for the static and dynamic deflections to be determined, TV _{x ... z} the probe vector to be determined, R _TK a radius of the probe body to be determined 114 , R _{KK is} a known radius of the calibration body 120 is.

Gleichzeitig gilt Kugelbedingung (1). Radienfehler sind zu minimieren. Das Ergebnis der Korrekturfunktion kann als Eingangsgröße Px,i..z,i in der Kugelfunktion verwendet werden. Das Optimum ist dann gefunden, wenn man die 9 Koeffizienten der ersten 3x3 Matrix zur Korrektur der statischen Verformung, die 9 Koeffizienten der zweiten 3x3 Matrix zur Korrektur der quasi-statischen Verformung bei angenommener konstanter Beschleunigung, die 3 Komponenten des Tastvektors sowie den Radius der Tastkugel so bestimmt hat, dass die Radienfehler nicht weiter verkleinert werden können, im besten Fall also Null werden. Es können dabei auch Freiheitsgrade gesperrt und die entsprechenden Parameter durch Vorgabewerte oder Zwangsbedingungen ersetzt werden. So können die 3x3 Matrizen auch mit jeweils 6 Freiheitsgraden berechnet werden, wenn man symmetrische Matrizen definiert. Gleichzeitig oder alternativ kann der Radius der Tastkugel aus einer vorgelagerten Kalibriermessung, also zum Beispiel aus einem mitgelieferten Kalibrierschein, bekannt sein. Entsprechend kann sich also die Zahl der Freiheitsgrade verringern.The resulting system of linear equations with 4 + 9 + 9 = 22 unknowns can be solved with a corresponding permutation of the speed and contact force and a correspondingly high number of recorded measured values. The optimization calculation is based on the "correction function" shown above $\overrightarrow{{\mathrm{P.}}_{kOr}}.$

At the same time, spherical condition (1) applies. Radius errors are to be minimized. The result of the correction function can be used as input variable Px, i..z, i in the spherical function. The optimum is found when the 9 coefficients of the first 3x3 matrix for correcting the static deformation, the 9 coefficients of the second 3x3 matrix for correcting the quasi-static deformation with assumed constant acceleration, the 3 components of the probe vector and the radius of the probe ball has determined in such a way that the radius errors cannot be further reduced, in the best case they become zero. Degrees of freedom can also be blocked and the corresponding parameters replaced by default values or constraints. The 3x3 matrices can also be calculated with 6 degrees of freedom each if you define symmetrical matrices. At the same time or alternatively, the radius of the probe ball can be known from an upstream calibration measurement, for example from a calibration certificate supplied. Accordingly, the number of degrees of freedom can be reduced.

In Vektor- bzw. Matrixschreibweise können die korrigierten Messwerte $\overrightarrow{P_{kor}}=\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]$

geschrieben werden als $$\begin{array}{l}\left[\begin{array}{c}{P}_{x,i}\\ P_{y,i}\\ P_{z,i}\end{array}\right]=\overrightarrow{P_{raw}}+\left[\begin{array}{ccc}{M}_{stat\mathrm{,11}}& M_{stat\mathrm{,12}}& M_{stat\mathrm{,13}}\\ M_{stat\mathrm{,21}}& M_{stat\mathrm{,22}}& M_{stat\mathrm{,23}}\\ M_{stat\mathrm{,31}}& M_{stat\mathrm{,32}}& M_{stat\mathrm{,33}}\end{array}\right]\overrightarrow{F}+\left[\begin{array}{ccc}{M}_{dyn\mathrm{,11}}& M_{dyn\mathrm{,12}}& M_{dyn\mathrm{,13}}\\ M_{dyn\mathrm{,21}}& M_{dyn\mathrm{,22}}& M_{dyn\mathrm{,23}}\\ M_{dyn\mathrm{,31}}& M_{dyn\mathrm{,32}}& M_{dyn\mathrm{,33}}\end{array}\right]\overrightarrow{a}\\ +\left[\begin{array}{ccc}{M}_{ruck\mathrm{,11}}& M_{ruck\mathrm{,12}}& M_{ruck\mathrm{,13}}\\ M_{ruck\mathrm{,21}}& M_{ruck\mathrm{,22}}& M_{ruck\mathrm{,23}}\\ M_{ruck\mathrm{,31}}& M_{ruck\mathrm{,32}}& M_{ruck\mathrm{,33}}\end{array}\right]\overrightarrow{\dot{a}}+\left[\begin{array}{c}{V}_{temp,x}\\ V_{temp,y}\\ V_{temp,z}\end{array}\right]T\\ \\ =\left[\begin{array}{c}{P}_{rawx,i}\\ P_{rawy,i}\\ P_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{F}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{F}_z}\end{array}\right]\left[\begin{array}{c}{F}_{x,i}\\ F_{y,i}\\ F_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_z}\end{array}\right]\left[\begin{array}{c}{\dot{a}}_{x,i}\\ {\dot{a}}_{y,i}\\ {\dot{a}}_{z,i}\end{array}\right]+\\ \left[\begin{array}{c}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }T}\end{array}\right]T,\end{array}$$

wobei M_ruck,11...M_ruck,33 zu ermittelnde Koeffizienten des Effektes „Verbiegung durch Ruck“, a_x...z,i bekannte Änderungen der Beschleunigungen des i-ten Antastpunkts, T bekannte Temperaturwerte, und V_temp,x...z zu ermittelnde vektorielle Einflüsse durch die Temperatur sind. Die Änderung der Beschleunigung und Temperatur können gemessen werden und/oder können vorbestimmt sein.The method can include calibration for at least one further influencing variable. The further influencing variable can be, for example, a temperature or a change in the acceleration, also referred to as a jerk. However, other influencing variables are also conceivable. In step a) 122 the other influencing factor can be varied. In step b) 124 the other influencing factor can be taken into account. The linear system of equations can be offset by effects such as "bending due to jerk" and / or influences due to temperature: $$\overrightarrow{{\mathrm{P.}}_{kOr}}=\overrightarrow{{\mathrm{P.}}_{raw}}+{\mathrm{M.}}_{stat}\overrightarrow{\mathrm{F.}}+{\mathrm{M.}}_{dyn}\overrightarrow{a}+{\mathrm{M.}}_{ruck}\overrightarrow{\dot{a}}+\overrightarrow{V_{temp}}T.$$

The corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}=\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]$

be written as $$\begin{array}{l}\left[\begin{array}{c}{\mathrm{P.}}_{x,i}\\ {\mathrm{P.}}_{y,i}\\ {\mathrm{P.}}_{z,i}\end{array}\right]=\overrightarrow{{\mathrm{P.}}_{raw}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{stat\mathrm{,\; 11}}& {\mathrm{M.}}_{stat\mathrm{,\; 12}}& {\mathrm{M.}}_{stat\mathrm{,\; 13}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 21}}& {\mathrm{M.}}_{stat\mathrm{,\; 22}}& {\mathrm{M.}}_{stat\mathrm{,\; 23}}\\ {\mathrm{M.}}_{stat\mathrm{,\; 31}}& {\mathrm{M.}}_{stat\mathrm{,\; 32}}& {\mathrm{M.}}_{stat\mathrm{,\; 33}}\end{array}\right]\overrightarrow{\mathrm{F.}}+\left[\begin{array}{ccc}{\mathrm{M.}}_{dyn\mathrm{,\; 11}}& {\mathrm{M.}}_{dyn\mathrm{,\; 12}}& {\mathrm{M.}}_{dyn\mathrm{,\; 13}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 21}}& {\mathrm{M.}}_{dyn\mathrm{,\; 22}}& {\mathrm{M.}}_{dyn\mathrm{,\; 23}}\\ {\mathrm{M.}}_{dyn\mathrm{,\; 31}}& {\mathrm{M.}}_{dyn\mathrm{,\; 32}}& {\mathrm{M.}}_{dyn\mathrm{,\; 33}}\end{array}\right]\overrightarrow{a}\\ +\left[\begin{array}{ccc}{\mathrm{M.}}_{ruck\mathrm{,\; 11}}& {\mathrm{M.}}_{ruck\mathrm{,\; 12}}& {\mathrm{M.}}_{ruck\mathrm{,\; 13}}\\ {\mathrm{M.}}_{ruck\mathrm{,\; 21}}& {\mathrm{M.}}_{ruck\mathrm{,\; 22}}& {\mathrm{M.}}_{ruck\mathrm{,\; 23}}\\ {\mathrm{M.}}_{ruck\mathrm{,\; 31}}& {\mathrm{M.}}_{ruck\mathrm{,\; 32}}& {\mathrm{M.}}_{ruck\mathrm{,\; 33}}\end{array}\right]\overrightarrow{\dot{a}}+\left[\begin{array}{c}{V}_{temp,x}\\ V_{temp,y}\\ V_{temp,z}\end{array}\right]T\\ \\ =\left[\begin{array}{c}{\mathrm{P.}}_{rawx,i}\\ {\mathrm{P.}}_{rawy,i}\\ {\mathrm{P.}}_{rawz,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\mathrm{F.}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\mathrm{F.}}_z}\end{array}\right]\left[\begin{array}{c}{\mathrm{F.}}_{x,i}\\ {\mathrm{F.}}_{y,i}\\ {\mathrm{F.}}_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{a}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{a}_z}\end{array}\right]\left[\begin{array}{c}{a}_{x,i}\\ a_{y,i}\\ a_{z,i}\end{array}\right]+\left[\begin{array}{ccc}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }x}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }y}{\mathrm{\Delta }{\dot{a}}_z}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_x}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_y}& \frac{\mathrm{\Delta }z}{\mathrm{\Delta }{\dot{a}}_z}\end{array}\right]\left[\begin{array}{c}{\dot{a}}_{x,i}\\ {\dot{a}}_{y,i}\\ {\dot{a}}_{z,i}\end{array}\right]+\\ \left[\begin{array}{c}\frac{\mathrm{\Delta }x}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }y}{\mathrm{\Delta }T}\\ \frac{\mathrm{\Delta }z}{\mathrm{\Delta }T}\end{array}\right]T,\end{array}$$

where M _{ruck, 11} ... M _{ruck, 33} coefficients to be determined for the “bending by jerk” effect, a _{x ... z, i} known changes in the accelerations of the i-th touch point, T known temperature _{values, and V temp, x ... z} are vectorial influences to be determined by the temperature. The change in acceleration and temperature can be measured and / or can be predetermined.

2 shows an embodiment of a coordinate measuring machine according to the invention 116 . The coordinate measuring machine 116 can be a portal measuring device or a bridge measuring device. The coordinate measuring machine 116 can use a measuring table 126 have for supporting at least one workpiece to be measured. The coordinate measuring machine 116 can have at least one portal 128 have which at least a first vertical column 130 , at least a second vertical column 132 and one the first vertical column 130 and the second vertical column 132 connecting traverse 134 having. At least one vertical column 130 , 132 selected from the first and second vertical columns can be placed on the measuring table 126 be movably mounted. The horizontal direction can be a direction along a y-axis. The coordinate measuring machine 116 can have a coordinate system, for example a Cartesian coordinate system or a spherical coordinate system. Other coordinate systems are also conceivable. An origin or zero point of the coordinate system can, for example, be provided by a sensor of the coordinate measuring device, in particular the tactile sensor according to the invention 112 be given. An x-axis can be perpendicular to the y-axis, in a plane of the support surface of the measuring table 126 run away. A z-axis, also called a longitudinal axis, can extend perpendicular to the plane of the support surface, in a vertical direction. The vertical pillars 130 , 132 can extend along the z-axis. The traverse 134 can extend along the x-axis. The coordinate measuring machine 116 can have at least one measuring slide 136 have, which along the traverse 134 is movably mounted. In the measuring slide 136 a quill movable in a vertical direction, for example along the z-axis, can be mounted. At a lower end of the quill, in particular an end pointing in the direction of the support surface, the tactile sensor can, for example 112 be arranged. The coordinate measuring machine 116 has the at least one tactile sensor 112 with the at least one probe body. The tactile sensor 112 can be interchangeable with the coordinate measuring machine 116 be connected. The coordinate measuring machine 116 has the at least one calibration body 120 on.

The coordinate measuring machine 116 has at least one controller 138 on. The control 138 is set up the probe body 114 along the at least one trajectory along the surface of the calibration body 120 to move and take a plurality of measured values. The control 138 is set up when scanning the speed and force of the tactile sensor 112 to vary.

The control 138 can comprise at least one data processing device, for example at least one computer or microcontroller. The data processing device can have one or more volatile and / or non-volatile data memories, wherein the data processing device can be set up in terms of programming, for example, to control the tactile sensor. The control 138 can furthermore comprise at least one interface, for example an electronic interface and / or a man-machine interface such as an input / output device such as a display and / or a keyboard. For example, one or more electronic connections can be made between the tactile sensor 112 and the control 138 be provided. The control 138 can for example be set up centrally or decentrally. Other configurations are also conceivable.

The coordinate measuring machine 116 has at least one evaluation unit 140 which is set up to evaluate the recorded measured values. The evaluation includes determining a tactile vector, at least one characteristic, geometric variable of the probing body, a static compliance of the tactile sensor and a dynamic compliance of the tactile sensor 112 . The evaluation unit 140 can for example comprise at least one data processing device, for example at least one computer or microcontroller. The data processing device can have one or more volatile and / or non-volatile data memories, it being possible for the data processing device to be set up in terms of programming, for example, to carry out an evaluation. The evaluation unit 140 can be part of the control 138 be.

List of reference symbols

110

Procedure

112

tactile sensor

114

Probe body

116

Coordinate measuring machine

118

Coordinate system

120

Calibration body

122

Step a)

124

Step b)

126

Measuring table

128

portal

130

first vertical column

132

second vertical column

134

traverse

136

Measuring slide

138

control

140

Evaluation unit

QUOTES INCLUDED IN THE DESCRIPTION

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

Patent literature cited

• DE 19861469 [0004]
• CN 103822603 [0005]
• EP 2447665 [0005]
• WO 030308375 [0005]
• WO 2005/090900 [0005]

Claims (10)

Method (110) for calibrating a tactile sensor (112) with at least one probe body (114), the method (110) having the following steps: a) generating at least one data set (122), the generating comprising scanning a calibration body (120), the probe body (114) being moved along at least one trajectory along a surface of the calibration body (120) and a plurality of measured values being recorded, the speed and force of the tactile sensor (112) being varied during scanning, b) evaluating the data record (124), wherein the evaluation of the data record comprises determining a tactile vector, at least one characteristic, geometric variable of the probe body, a static compliance of the tactile sensor (112) and a dynamic compliance of the tactile sensor (112). Method (110) according to the preceding claim, wherein the determination of the sensing vector, the characteristic, geometric size of the sensing body, the static compliance and the dynamic compliance take place simultaneously. Method (110) according to one of the preceding claims, wherein the calibration body (120) is a calibration sphere with a known radius. Method (110) according to one of the preceding claims, wherein the probe body (114) is a probe ball. Method (110) according to the preceding claim, wherein the characteristic, geometric size of the probe body (114) is a probe ball radius. Method (110) according to one of the preceding claims, wherein the evaluation includes determining corrected measured values $\overrightarrow{{\mathrm{P.}}_{kOr}}$

from the recorded measured values $\overrightarrow{{\mathrm{P.}}_{raw}}$

includes, where $\overrightarrow{{\mathrm{P.}}_{kOr}}=\overrightarrow{{\mathrm{P.}}_{raw}}+{\mathrm{M.}}_{stat}\overrightarrow{\mathrm{F.}}+{\mathrm{M.}}_{dyn}\overrightarrow{a},$

in which $\overrightarrow{\mathrm{F.}}$

the contact force and $\overrightarrow{a}$

are the acceleration of the tactile sensor (112) and the matrix M _stat includes coefficients of static compliance and the matrix M _dyn includes coefficients of dynamic compliance. The method (110) according to any one of the preceding claims, wherein the evaluation comprises solving the following minimization problem: $$min\Vert \sqrt{{\left({\mathrm{P.}}_{x,i}-T{V}_x\right)}^2+{\left({\mathrm{P.}}_{y,i}-T{V}_y\right)}^2{\left({\mathrm{P.}}_{z,i}-T{V}_z\right)}^2}-\left({\mathrm{R.}}_{TK}+{\mathrm{R.}}_{KK}\right)\Vert ,$$

where P _{x ... z, i} measuring points corrected by the static and dynamic deflections to be determined, TV _{x ... z} the probe vector to be determined, R _TK a radius of the probe body (114) to be determined, R _KK a known radius of the calibration body is. The method (110) according to any one of the preceding claims, wherein the method comprises a calibration for at least one further influencing variable, the further influencing variable being varied in step a) (122), the further influencing variable being taken into account in step b) (124), where the further influencing variable is a temperature or a change in the acceleration. Computer program which, when run on a computer or computer network, carries out the method (110) according to one of the preceding claims. Coordinate measuring device (116) for measuring at least one workpiece, the coordinate measuring device (116) having at least one tactile sensor (112) with at least one probe body (114), the coordinate measuring device (116) having at least one calibration body (120), the coordinate measuring device ( 116) has at least one controller (138), the controller (138) being set up to move the probe body (114) along at least one trajectory along a surface of the calibration body (120) and to record a plurality of measured values, the controller (138) is set up to vary the speed and contact force of the tactile sensor (112) during scanning, the coordinate measuring device (116) having at least one evaluation unit (140) which is set up to evaluate the recorded measured values, the evaluation being a determination of a feeler vector, at least one characteristic, geometric size of the probe body, a static compliance of the tactile sensor (112) and a dynamic compliance of the tactile sensor (112).

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