DE102019110111B4 - Method for self-calibration of a position measuring device - Google Patents

Abstract

Method for determining a position information (γ), in particular an angle of rotation information, of a moving object (11) with a position measuring device (10), - which has a first sensor (1) for generating a first sensor signal (C) and - along a movement path of the moving object Object (11) relative to the first sensor (1) by a predetermined distance (A), in particular angular distance, arranged offset second sensor (2) for generating a second sensor signal (S), wherein in a calibration process (100) an assignment of a combination of the first sensor signal (C) and the second sensor signal (S) for a position indication (y) of the moving object (11), in particular an indication of the angle of rotation of the moving object (11), is determined and wherein in a measuring process (101 ) based on the determined assignment and the first and second sensor signals (C, S), a position (y) of the moving object (11) is determined, characterized in that to determine the assignment in the calibration process (100), the moving object (11 ) is moved relative to the first and the second sensor (1, 2) and a first time profile (3) of the first sensor signal (C) and a second time profile (4) of the second sensor signal (S) are determined, and a plurality of time point pairs ( 201-227, 301-315) with a first point in time of the first time profile (3) and a second point in time of the second time profile (4), the first sensor signal (C) essentially corresponding to the second sensor signal ( S) at the second point in time, the assignment being determined on the basis of the predetermined distance (A) and on the basis of the pairs of points in time (201-227, 301-315) determined.

Description

The invention relates to a method for determining a position specification, in particular a rotational angle specification, of a moving object with a position measuring device, which offsets a first sensor for generating a first sensor signal and one along a movement path of the object relative to the first sensor by a predetermined distance, in particular angular distance arranged second sensor for generating a second sensor signal, wherein in a calibration process an assignment of a combination of the first sensor signal and the second sensor signal to an indication of the position of the object, in particular an indication of the angle of rotation of the object, is determined and wherein in a measurement process that follows the calibration process on the basis of the determined Assignment and the first and the second sensor signal a position of the object is determined.

A reference sensor that works with increased accuracy is typically used in the calibration process to determine the assignment. A reference measurement is generally carried out by means of such a reference sensor, on the basis of which an indication of the position of the object is determined. This is then assigned to the corresponding values of the first and second sensor signals and stored in a memory, for example as a table. This assignment can be used in the subsequent measurement process in order to determine the most accurate position information possible for the object. Due to the reference sensor, the procedure described entails a certain outlay in terms of equipment.

The U.S. 2011/0 193 552 A1 describes a measuring system for a rotating component, on the surface of which circumferentially aligned bands of magnetizable material are formed, near each of which a magnetic field sensor is arranged which detects a magnetic pattern recorded on the band during rotation.

The US 2015 / 0 077 093 A1 describes a rotation angle detection device with two magnetic sensors arranged offset from one another by 120 degrees about the rotation axis, the functioning/failure of which is determined.
Against this background, the task is to enable a position measuring device of the type mentioned at the outset to be calibrated with little effort.

The object is achieved by a method for determining a position specification, in particular a rotational angle specification, of a moving object with a position measuring device which has a first sensor for generating a first sensor signal and a distance along a movement path of the object relative to the first sensor by a predetermined distance, in particular angular distance , offset arranged second sensor for generating a second sensor signal,
wherein in a calibration process an assignment of a combination of the first sensor signal and the second sensor signal to an indication of the position of the object, in particular an indication of the angle of rotation of the object, is determined and
in a measurement process that follows the calibration process, a position specification of the object is determined on the basis of the determined association and the first and second sensor signals,
wherein for determining the assignment in the calibration process
the object is moved relative to the first and the second sensor and a first time profile of the first sensor signal and a second time profile of the second sensor signal are determined, and
several time pairs are determined with a first time of the first curve and a second time of the second curve, the first sensor signal at the first time essentially corresponding to the second sensor signal at the second time, and
the assignment being determined on the basis of the determined time point pairs.

According to the invention, the assignment in the calibration process can take place without a reference measurement solely on the basis of the sensor signals determined by the first and second sensors of the position measuring device. In this respect one can speak of a self-calibration of the position measuring device. The first time profile of the first sensor signal and the second time profile of the second sensor signal are determined and optionally stored. In the first and the second profile, pairs of points in time are determined, each consisting of two points in time, which are characterized in that the first sensor signal has essentially the same value at the first point in time as the second sensor signal at the second point in time. The pairs of times thus indicate times at which the object or the same section of the object is in each case in the range of the respective sensor. The distance between the sensors is therefore dependent on the distance between the first and the second point in time of each point in time pair. It is therefore possible to use knowledge of the constant distance between the two sensors for calibration. The method according to the invention has the advantage that complex calibration with a reference sensor is not required. The position measuring device can be calibrated in the installed state or during operation take place and enables the calibration to be carried out with reduced equipment costs.

In the calibration process, the object is preferably moved in a translatory or rotary manner, that is to say rotated about an axis of rotation. The movement of the object in the calibration process can cover a complete working area of the object or just a partial area of the working area. In a method for determining an indication of the angle of rotation, the object can be moved by a complete rotation or a rotation range smaller than a complete rotation or by a rotation range greater than a complete rotation.

The calibration process is particularly preferably carried out without a reference sensor, i.e. without a position specification being determined by means of a reference sensor. In particular, the first sensor and the second sensor of the position-measuring device are the only sensors that determine sensor signals dependent on position information of the object in the calibration process.

According to the invention, it is provided that the assignment is additionally determined in the calibration process using the specified distance. The specified distance can be assumed to be known for the calibration, so that it is not available as an unknown variable but as a known parameter during the determination. The distance can be an angular distance, ie an angular range by which a section of the object is rotated and at the start of which the section sweeps past the first sensor and at the end of which the section sweeps past the second sensor.

An embodiment of the method is preferred, wherein in the calibration process each of the points in time of a point in time pair is assigned a position information and the difference in the position information corresponds to the predetermined distance between the first and second sensors.

umfasst, wobei γ_n,1 eine erste Positionsangabe in dem ersten Zeitpunkt des n-ten Zeitpunktpaars (Anfang des zeitlichen Intervalls) und γ_n,2 eine zweite Positionsangabe in dem zweiten Zeitpunkt des n-ten Zeitpunktpaars (Ende des zeitlichen Intervalls) bezeichnet und A der vorgegebene Abstand des ersten und zweiten Sensors ist.An advantageous embodiment of the invention provides that a system of equations with n equations is formed in the calibration process, which has an equation of the form at each point in time $$g_{n\mathrm{,2}}-g_{n\mathrm{,1}}=A$$

comprises, where γ _n,1 denotes a first position indication in the first point in time of the nth point in time pair (beginning of the time interval) and γ _n,2 denotes a second position indication in the second point in time of the nth point in time pair (end of the time interval) and A is the predetermined distance of the first and second sensors.

In this context, it has proven to be advantageous if, in order to reduce unknowns in the system of equations, several, in particular at most half, of the first position information γ _n,1 is replaced by an approximate value which is dependent on at least two further first position information and several in particular at most half of the second position information γ _n,2 is replaced by an approximate value which is dependent on at least two further second position information. Since the system of equations described above comprises two unknowns per equation, in particular the first position specification γ _n,1 at the first time and the second position specification γ _n,2 at the second time, it is possible by reducing the unknowns to find a unique solution to the to get the system of equations. In particular, half of the first position information γ _n,1 is replaced by a first approximate value that depends on at least two adjacent first position information and/or half of the second position information γ _n,2 is replaced by a second approximate value that depends on at least two adjacent second position information is dependent.

It is preferred if the approximate value is a linear approximate value, which makes it possible to determine the approximate value in a particularly simple manner.

According to an advantageous embodiment, it is provided that the approximate value is dependent on at least three, preferably at least four, further first position details. The accuracy can be increased by formulating the approximate value in this way as a function of at least three further first position details.

A preferred embodiment provides that, to reduce unknowns in the system of equations, at least a first and a second of the pairs of points in time are selected such that the second point in time of the first point in time pair is identical to the first point in time of the second point in time pair. A further reduction in unknowns in the above-mentioned system of equations can be achieved by such a choice. In this respect, the intervals defined by the pairs of points in time can be selected in succession without gaps.

An embodiment in which the first sensor and the second sensor are magnetic field sensors has proven to be advantageous. Low-loss and smooth position detection can be enabled via the magnetic field sensors.

An advantageous embodiment of the method provides that the system of equations is solved in order to determine unknowns of the system of equations, in particular first and second position information. A method known per se can be used to solve the system of equations, for example a method for solving the system of equations according to the Gauss algorithm.

According to an advantageous embodiment of the method, it is provided that the first sensor signal is a periodic, in particular sinusoidal, sensor signal and the second sensor signal is a periodic, in particular sinusoidal, sensor signal.

The first sensor signal and/or the second sensor signal is preferably a voltage signal or a current signal. Alternatively, the first sensor signal and/or the second sensor signal can each be an n-tuple, in particular a pair, multiple voltage signals or multiple current signals. As a further alternative, it is possible for the first sensor signal and/or the second sensor signal to be a preprocessed voltage signal or a current signal or a digital signal, for example a voltage signal or a current signal or a digital signal, which is generated by a combination of several, in particular two, Raw signals or measurements is obtained.

An embodiment is advantageous in which first and second sensor signals are assigned to the determined first and second position information on the basis of the first and second profile.

According to a preferred embodiment, it is provided that in the calibration process a continuous assignment of a combination of the first sensor signal and the second sensor signal to a position indication of the object is determined by means of an interpolation algorithm. Such a configuration makes it possible to determine a calibrated position indication even for such combinations of the first and second sensor signals for which no time pairs were formed in the calibration process.

• 1 ein Ausführungsbeispiel einer Positionsmesseinrichtung, bei der das erfindungsgemäße Verfahren Anwendung finden kann;
• 2 zwei beispielhafte zeitliche Verläufe eines ersten und zweiten Sensorsignals mit markierten Zeitpunktpaaren mit einem ersten Zeitpunkt des ersten Verlaufs und einem zweiten Zeitpunkt des zweiten Verlaufs, wobei das erste Sensorsignal in dem ersten Zeitpunkt im Wesentlichen dem zweiten Sensorsignal in dem zweiten Zeitpunkt entspricht;
• 3 eine Darstellung von Zeitpunkten eines Verlaufs zur Veranschaulichung der Bestimmung eines Näherungswerts einer Positionsangabe;
• 4 zwei beispielhafte zeitliche Verläufe eines ersten und zweiten Sensorsignals mit lückenlos aneinandergereihten Zeitpunktpaaren;
• 5 eine beispielhafte Zuordnung eines ersten und eines zweiten Sensorwerts zu einer Positionsangabe;
• 6 eine beispielhafte Tabelle mit Messwerten eines Kalibriervorgangs;
• 7 eine beispielhafte Tabelle mit ersten und zweiten Zeitpunkten mehrerer Zeitpunktpaare; und
• 8 eine beispielhafte Tabelle mit einer Zuordnung jeweils einer Kombination des ersten Sensorsignals und des zweiten Sensorsignals zu einer Positionsangabe des Objekts.

Further details and advantages of the invention will be explained below with reference to the embodiment shown in the drawings. Herein shows:

• 1 an exemplary embodiment of a position measuring device in which the method according to the invention can be used;
• 2 two exemplary time curves of a first and second sensor signal with marked time pairs with a first time of the first curve and a second time of the second curve, the first sensor signal at the first time essentially corresponding to the second sensor signal at the second time;
• 3 a representation of points in time of a course to illustrate the determination of an approximate value of a position specification;
• 4 two exemplary time curves of a first and second sensor signal with pairs of points in time lined up without gaps;
• 5 an exemplary assignment of a first and a second sensor value to a position indication;
• 6 an exemplary table with measured values of a calibration process;
• 7 an exemplary table with first and second times of several pairs of times; and
• 8th an exemplary table with an assignment in each case of a combination of the first sensor signal and the second sensor signal to an indication of the position of the object.

In the 1 an exemplary position measuring device 10 for determining a position indication of a moving object 11, here for determining a rotational position of a rotatable moving object 11, is shown schematically, in which the method according to the invention can be used. Position measuring device 10 includes a first sensor 1 for generating a first sensor signal C and a second sensor 2 for generating a second sensor signal S, which is arranged offset along the movement path of moving object 11 relative to first sensor 1 by a predetermined distance, here an angular distance. The sensors 1, 2 of the position measuring device 10 are arranged offset by an angular distance of 90° and can, for example, be in the form of magnetic field sensors that detect a magnetic field of the moving object 11. For example, the magnetic field sensors can be designed as Hall sensors or as GMR sensors, which are based on the effect of giant magnetoresistance. The moving object 11 can have exactly one magnet with exactly one north pole and exactly one south pole. Alternatively, it is possible for the moving object 11 to comprise a plurality of magnets, so that there is a multi-pole arrangement with north poles and south poles arranged alternately on the moving object 11 .

$$S\left(\gamma \right)=B\cdot \text{sin}\left(\gamma \right)$$

kann der Drehwinkel γ des bewegten Objekts 11 berechnet werden als: $$\gamma \left(t\right)=\text{arctan}\left(\frac{C\left(t\right)}{S\left(t\right)}\right)$$

In the case of the position measuring device 10, the position information can be given in the form of the angle of rotation as a function of the first sensor signal C and the second sensor signal S. With sinusoidal sensor signals C, S with an amplitude 8 according to $$C\left(g\right)=B\cdot \text{cos}\left(g\right)$$

$$S\left(g\right)=B\cdot \text{sin}\left(g\right)$$

the angle of rotation γ of the moving object 11 can be calculated as: $$g\left(t\right)=\text{arctan}\left(\frac{C\left(t\right)}{S\left(t\right)}\right)$$

In conditions in which there is a non-sinusoidal magnetic field or the sensors exhibit non-linearity, however, it is necessary to calibrate the position measuring device 10 in a calibration process, with an assignment of a combination of the first sensor signal C and the second sensor signal S to a rotational angle specification γ of the moving Object 11 is determined. According to the invention, this calibration process can be carried out without a reference sensor being required for detecting the indication of the angle of rotation γ. Rather, it is possible to obtain the assignment solely with the aid of the sensor signals determined during the movement of the moving object 11 .

With the position measuring device 1 an evaluation unit is provided, which can be operated either in a calibration mode, in order to carry out a calibration process 100, or in a measurement mode, in order to carry out a measurement process 101. This circumstance is in 1 represented by two blocks 100, 101, between which it is possible to switch back and forth by means of a plurality of switches 102. In calibration process 100, an assignment of a combination of first sensor signal C and second sensor signal S to a position specification γ of moving object 11 is determined, and in measuring process 101, a position specification is determined using the assignment determined in calibration process 100 and the first and second sensor signals γ of the moving object 11 is determined.

According to a modification of the 1 In the exemplary embodiment shown, the switches 102 can be omitted. In such a modification, the evaluation unit is operated in such a way that a calibration process 100 and a measurement process 101 are carried out at the same time. This makes it possible to calibrate the position measuring device during operation and/or to detect a deterioration in the measuring accuracy during operation.

The representation in 2 FIG. 12 shows a first time profile 3 of the first sensor signal C and a second time profile 4 of the second sensor signal S, as they can be detected as part of the calibration process 100. In this case, the moving object 11 is moved over the entire working range of the position measuring device 10 . In the present case of a position measuring device 10 for determining a rotational position of the rotatable moving object 11, the moving object 11 is rotated through a complete revolution, ie through 360°. In this case, the first sensor signal C of the first sensor 1 and the second sensor signal S of the second sensor 2 are stored together with the respective time values. For example, these time curves 3, 4 can each have 1000 points in time consisting of a value of a sensor signal C, S and the associated time value. An exemplary table with such measured values of a calibration process is in 6 shown.

Typically, the amplitudes of the first sensor signal C and the second sensor signal S are essentially identical. If the amplitudes of the first sensor signal C and the second sensor signal S deviate from one another, the amplitudes of the first and second sensor signals C, S can first be compared. With such an adjustment, an amplification and/or an offset of the first and second sensor signals C, S can be adjusted in such a way that the amplitude, or the maximum and the minimum, are essentially identical for both sensors 1, 2. In addition, outliers caused by high-frequency interference, for example, can be smoothed using a smoothing process.

As an alternative to the in 6 In the table shown with measured values, the time profiles 3.4 can be approximated as a function over time in order to obtain additional values between those in the table 6 to obtain the times shown.

As shown in 2 It can further be seen that the time curves 3, 4 are not ideal sinusoidal curves, but rather show deviations from the ideal sinusoidal shape. The completion of a rotation of the moving object 11 by 360° can be determined by comparing a current pair of values of the first sensor signal C and the second sensor signal S with a stored pair of values of the first sensor signal C and the second sensor signal S. The stored pair of values is preferably a pair of values stored at the beginning of the calibration process 100 .

Based on the first and second profile 1, 2 of the sensor signals C, S, several time pairs each with a first time of the first profile and a second time of the second course determined. The first and second point in time of a point in time pair are selected in such a way that the first sensor signal C at the first point in time essentially corresponds to the second sensor signal S at the second point in time. Thus, these time pairs define time intervals between the beginning and end of which the moving object 11 has rotated exactly by the angular distance between the first and second sensors 1, 2. The number of time point pairs can be freely selected. In the present example 2 a total of 29 such time point pairs are formed, which can also be understood as a time interval.

The pairs of points in time are preferably selected using the following criteria. Since the course of the sensor signals C, S is comparatively flat in the area of the maxima and minima, only slight changes in the sensor signal occur in these areas in the event of changes over time. The pairs of points in time are therefore preferably selected in such a way that their first and second points in time are not in the areas of the maxima and minima. Furthermore, it is preferred if all pairs of points in time form time intervals that lie completely within one revolution of the working area, in this case a rotation of 360°. In the present exemplary embodiment, the last point in time 329, here point in time, is selected in such a way that the second point in time of this point in time has a pair of values from the first and second sensor signal C, S, which is essentially identical to the pair of values from the first and second sensor signal C, S in the first Time of the first time point pair.

The representation in 7 shows an example table with measured values for a total of 72 time point pairs or time intervals.

umfasst, wobei γ_n,1 eine erste Positionsangabe in dem ersten Zeitpunkt des n-ten Zeitpunktpaars und γ_n,2 eine zweite Positionsangabe in dem zweiten Zeitpunkt des n-ten Zeitpunktpaars bezeichnet und A der vorgegebene Abstand des ersten Sensors 1 und zweiten Sensors 2 ist.The assignment of a combination of the first sensor signal C and the second sensor signal S to an indication of the position of the object 11 is now determined based on the specific time pairs and also based on the specified angular distance A, here 90°, of the first and second sensors 1, 2. A system of equations with n equations is formed in the calibration process 100, which has an equation of the form at each point in time $$g_{n\mathrm{,2}}-g_{n\mathrm{,1}}=A$$

where γ _n,1 denotes a first position specification at the first point in time of the nth point in time pair and γ _n,2 denotes a second position specification at the second point in time of the nth point in time pair and A is the specified distance between the first sensor 1 and the second sensor 2 is.

In this respect, a system of equations with n equations and 2n unknowns is initially obtained. In order to solve this system of equations, the number of unknowns is reduced. To reduce unknowns in the system of equations, at most half of the first position information γ _n,1 is replaced by an approximate value that depends on at least two other first position information y _n-1,1 , y _n+1,1 and at most half of the second position information γ _n,2 is replaced by an approximate value which is dependent on at least two further second position information γ _n-1,2 , γ _n+1,2 . In the present exemplary embodiment, every second of the first position information γ _n,1 is replaced by a first approximate value and every second of the second position information is replaced by a second approximate value.

ergibt sich $${\gamma }_n=e_n\cdot {\gamma }_{n-1}+{ƒ}_n\cdot {\gamma }_{n+1}$$

mit $$e_n=\frac{t_{n+1}-t_n}{t_{n+1}-t_{n-1}}$$

und $${ƒ}_n=\frac{t_n-t_{n-1}}{t_{n+1}-t_{n-1}}.$$

A model of the movement of the moving object 11 can be used to calculate the approximation. In order to enable an approximation that is particularly easy to obtain, a linear approximation can be selected as the approximation, in particular a linear approximation between the respective two adjacent first position details γ _n−1,1 , γ _n+1,1 or second position details γ _{n−1 .2} , γn _+1.2 . An example of a linear approximation calculation is given in 3 shown. Here the position information γ _n is estimated using the adjacent first position information γ _n−1 , γ _n+1 . out of the equation $$\frac{g_n-g_{n-1}}{g_{n+1}-g_{n-1}}=\frac{t_n-t_{n-1}}{t_{n+1}-t_{n-1}}$$

surrendered $$g_n=e_n\cdot g_{n-1}+{ƒ}_n\cdot g_{n+1}$$

with $$e_n=\frac{t_{n+1}-t_n}{t_{n+1}-t_{n-1}}$$

and $${ƒ}_n=\frac{t_n-t_{n-1}}{t_{n+1}-t_{n-1}}.$$

By replacing half of the first and second position information γ _n,1 , γ _n,2 with the approximation values described above, the number of unknowns in the system of equations is halved. The system of equations thus comprises a total of n equations with n unknowns and can be solved using one of the usual solution methods, for example using the Gauss algorithm.

According to a deviation from the method steps explained above for determining an approximate value of a first position information γ _{n,1 ,} the approximate value can be dependent on at least three, preferably four, further first position information. Correspondingly, in order to determine an approximate value of a second position information γ _{n,2 ,} the approximate value can be dependent on at least three, preferably four, further second position information.

A reduction of the unknowns in the system of equations is optionally possible. For this purpose, a first point in time, ie a starting point in time, of a first pair of points in time can be selected in such a way that it coincides with a second point in time, ie an end point in time, of a second point in time pair. A first example of such a selection of time point pairs is shown in Fig 2 shown. The first points in time of the point in time pairs or intervals 219 and 220 are identical to the second points in time in the point in time pairs or intervals 214 and 215. Another example of such a selection is in 4 shown. According to 4 the points in time of three pairs of points in time 301, 306, 311 are fixed without gaps. The second point in time of a first point in time pair 301 is selected in such a way that it coincides with the first point in time in a second point in time pair 306 and the first point in time in a third point in time pair 311 is selected in such a way that it coincides with the second point in time of the second point in time pair 306.

If the pairs of points in time are partially defined as adjacent to one another without gaps, as is the case in 4 is shown, it is possible to replace less than half of the first and second position information with a corresponding approximation. In particular, it can be provided that at least a quarter of the first position information γ _n,1 is replaced by a first approximate value, which is dependent on at least two further first position information and at least a quarter of the second position information γ _n,2 is replaced by a second approximate value is, which is dependent on at least two other second position information.

Finally, the system of equations is solved with n equations in order to determine the at most n unknowns. These unknowns are the position information γ _n,1 , γ _n,2 . These position details γ _n,1 γ _n,2 are each assigned to a point in time t _n by the first profile 1 and the second profile 2 and can thus each be assigned to a combination of the first sensor signal C and the second sensor signal S. A table with such an assignment of a combination of the first sensor signal C and the second sensor signal S to a position specification γ of the moving object 11 is in 8th shown.

In order to obtain a constant assignment, an interpolation algorithm is used in the calibration process, which determines a constant assignment of the combination of the first sensor signal C and the second sensor signal S to the position specification γ of the moving object 11 . A graphical representation of such a continuous assignment between the combination of the first sensor signal C and the second sensor signal S to a position specification γ of the object 11 is shown in FIG 5 shown.

In the measurement process, the assignment determined in the calibration process is then determined according to 8th or. 5 and a position specification γ of the moving object 11 is determined on the basis of the first and second sensor signals C, S measured in the measuring process. For this purpose, the value of the position information γ from the table 8th read out, which corresponds to the measured combination of the first and second sensor signals C, S or comes closest to this. Alternatively, the continuous assignment according to 8th used for this.

Reference List

1

first sensor

2

second sensor

3

first timeline

4

second timeline

10

position measuring device

11

moving object

100

calibration process

101

measurement process

201-227

point in time pair

301-315

point in time pair

A

Distance

B

amplitude

C

first sensor signal

S

second sensor signal

γn,1

position indication

γn,2

position indication

g

position indication

Claims (9)

Method for determining a position specification (γ), in particular a rotational angle specification, of a moving object (11) with a position measuring device (10), - a first sensor (1) for generating a first sensor signal (C) and - one along a movement path of the moving object (11) opposite the first sensor (1) by a predetermined distance (A), in particular angular distance , offset arranged second sensor (2) for generating a second sensor signal (S), wherein in a calibration process (100) an assignment of a combination of the first sensor signal (C) and the second sensor signal (S) to a position specification (y) of the moving object (11), in particular an indication of the angle of rotation of the moving object (11), and in a measuring process (101) following the calibration process (100) based on the determined assignment and the first and second sensor signals (C, S), a position indication ( y) of the moving object (11) is determined, characterized in that to determine the assignment in the calibration process (100), the moving object (11) is moved relative to the first and the second sensor (1, 2) and a first time Course (3) of the first sensor signal (C) and a second time course (4) of the second sensor signal (S) is determined, and a plurality of time pairs (201-227, 301-315) with a first time point of the first time course (3) and a second point in time of the second time curve (4), the first sensor signal (C) at the first point in time essentially corresponding to the second sensor signal (S) at the second point in time, the allocation based on the specified distance (A) and is determined on the basis of the determined time point pairs (201-227, 301-315). procedure after claim 1 , characterized in that in the calibration process (100) an equation system with n equations is formed, which at each point in time pair (201-227, 301-315) an equation of the form $$g_{n\mathrm{,2}}-g_{n\mathrm{,1}}=A$$

includes, where γ _n,1 denotes a first position indication at the first point in time of the nth point in time pair and γ _n,2 denotes a second position indication in the second point in time of the nth point in time pair and A is the specified distance between the first sensor (1) and the second sensor (2) is. procedure after claim 2 , characterized in that to reduce unknowns in the system of equations, several, in particular at most half, of the first position information γ _n,1 is replaced by a first approximation value, which is dependent on at least two further first position information and several, in particular at most half , the second position information γ _n,2 is replaced in each case by a second approximate value which is dependent on at least two further second position information. procedure after claim 3 , characterized in that the approximation is a linear approximation. Procedure according to one of claims 3 or 4 , characterized in that the approximate value is dependent on at least three, preferably at least four, further first position data. Procedure according to one of claims 2 until 5 , characterized in that to reduce unknowns in the system of equations, at least a first and a second of the pairs of times (204, 205, 209, 210, 301-315) are selected such that the second point in time of the first pair of points in time is identical to the first point in time of the second time point. Procedure according to one of claims 2 until 6 , characterized in that the system of equations is solved in order to determine unknowns of the system of equations, in particular first and second position information. Method according to one of the preceding claims, characterized in that first and second sensor signals (C, S) are assigned to the determined first and second position information on the basis of the first and second time profile (3, 4). Method according to one of the preceding claims, characterized in that in the calibration process (100) by means of an interpolation algorithm, a continuous assignment of a combination of the first sensor signal (C) and the second sensor signal (S) to a position specification (y) of the moving object (11) is determined.

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