DE102019110111A1 - Method for self-calibration of a position measuring device - Google Patents

Abstract

The invention relates to a method for determining a position specification, in particular a rotation angle specification, of a moving object with a position measuring device, - which has 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 , has an offset arranged second sensor for generating a second sensor signal, an assignment of a combination of the first sensor signal and the second sensor signal to a position specification of the object, in particular a rotation angle specification of the object, being determined in a calibration process, and in a measurement process following the calibration process based on the Determined assignment and the first and the second sensor signal a position indication of the object is determined, wherein to determine the assignment in the calibration process, the object is moved relative to the first and the second sensor d 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 with a first time point of the first profile and a second time point of the second profile are determined, the first sensor signal being essentially at the first time corresponds to the second sensor signal at the second point in time, the assignment being determined on the basis of the specific point in time pairs.

Description

The invention relates to a method for determining a position specification, in particular a rotation angle specification, of a moving object with a position measuring device that 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 a position specification of the object, in particular a rotation angle specification of the object, is determined and wherein in a measurement process following the calibration process based on the determined Assignment and the first and the second sensor signal a position specification of the object is determined.

Typically, a reference sensor operating with increased accuracy is used in the calibration process to determine the assignment. By means of such a reference sensor, a reference measurement is usually carried out, on the basis of which a position specification 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 measuring process in order to determine the position of the object as precisely as possible. Due to the reference sensor, the procedure described involves a certain outlay in terms of equipment.

Against this background, the task arises of enabling the calibration of a position measuring device of the type mentioned at the beginning with little effort.

The object is achieved by a method for determining a position specification, in particular a rotation angle specification, of a moving object with a position measuring device which has a first sensor for generating a first sensor signal and a predetermined distance, in particular angular distance, along a movement path of the object relative to the first sensor , has an offset arranged second sensor for generating a second sensor signal,
wherein an assignment of a combination of the first sensor signal and the second sensor signal to a position specification of the object, in particular a rotation angle specification of the object, is determined in a calibration process, and
wherein in a measuring process following the calibration process, a position specification of the object is determined based on the determined assignment and the first and second sensor signals,
whereby to determine the assignment in the calibration process
the object is moved with respect 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
a plurality of time pairs with a first time of the first profile and a second time of the second profile are determined, 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 specific time 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 curve, time pairs each consisting of two times are determined, which are characterized in that in the first time the first sensor signal has essentially the same value as the second sensor signal in the second time. The point in time pairs thus indicate points in time at which the object or the same section of the object is located in the area 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 calibration of the position measuring device can take place in the installed state or during operation and enables the calibration to be carried out with reduced expenditure on equipment.

The object is preferably moved translationally or rotationally moved in the calibration process, that is to say rotated about an axis of rotation. The movement of the object in the calibration process can encompass a complete working area of the object or even a partial area of the working area. In a method for determining an indication of the angle of rotation, the movement of the object by a complete revolution or a range of rotation can be smaller than a complete revolution or by one The range of rotation is greater than one complete revolution.

The calibration process is particularly preferably carried out without a reference sensor, i. 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 that are dependent on position information of the object in the calibration process.

According to an advantageous embodiment of the invention, it is provided that the assignment in the calibration process is additionally determined on the basis of the predetermined distance. The specified decency can be assumed to be known for 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, i.e. an angular range by which a section of the object is rotated and at the beginning of which the section passes the first sensor and at the end of which the section passes the second sensor.

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

According to an alternative advantageous embodiment, the assignment can take place without knowledge of the predetermined distance. In such an embodiment, the distance is viewed as a further unknown variable which can also be determined with the aid of the method according to the invention.

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 an equation system with n equations is formed in the calibration process, which equation of the form at each time pair $${\gamma }_{n\mathrm{,\; 2}}-{\gamma }_{n\mathrm{,1}}=\mathrm{A.}$$

includes, where γ _{n, 1} a first position specification in the first point in time of the n-th point in time pair (start of the time interval) and γ _{n, 2} a second position specification in the second point in time of the n-th point in time pair (end of the time interval) denotes and A is the predetermined distance between the first and second sensors.

In this context, it has proven to be advantageous if, in order to reduce unknowns in the equation system, several, in particular at most half, of the first position information γ _{n, 1} is replaced by an approximate value that 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 that is dependent on at least two further second position information. Since the system of equations described above includes two unknowns per equation, in particular the first position specification γ _{n, 1} in the first time and the second position information γ _{n, 2} In the second point in time, the reduction of the unknown makes it possible to obtain a unique solution to the system of equations. In particular, half of the first position information γ _{n, 1} each replaced by a first approximate value that is dependent 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 is dependent on at least two adjacent second position information.

It is preferred if the approximate value is a linear approximate value, whereby a particularly simple determination of the approximate value is made possible.

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. Such a formulation of the approximate value as a function of at least three further first position details can increase the accuracy.

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

An embodiment has proven to be advantageous in which the first sensor and the second sensor are magnetic field sensors. The magnetic field sensors enable low-loss and smooth position detection.

An advantageous embodiment of the method provides that the system of equations is solved is to determine unknowns of the equation system, 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 in accordance with the Gaussian 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 in each case 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, a plurality of voltage signals or a plurality of current signals. Further alternatively, it is possible that the first sensor signal and / or the second sensor signal is in each case 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, by means of an interpolation algorithm, a continuous assignment of a combination of the first sensor signal and the second sensor signal to a position specification of the object is determined. Such a configuration makes it possible to also determine a calibrated position specification for combinations of the first and second sensor signals for which no time pairs have been 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 exemplary embodiment shown in the drawings. Herein shows:

• 1 an 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 point in time of the first curve and a second point in time of the second curve, the first sensor signal in the first point in time essentially corresponding to the second sensor signal in the second point in time;
• 3 a representation of points in time of a course to illustrate the determination of an approximate value of a position specification;
• 4th two exemplary time courses 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 specification;
• 6 an exemplary table with measured values of a calibration process;
• 7th an exemplary table with first and second times of a plurality of time pairs; and
• 8th an exemplary table with an assignment of a combination of the first sensor signal and the second sensor signal to a position specification of the object.

In the 1 is a schematic of an exemplary position measuring device 10 for determining a position specification of an object 11 , here to determine a rotational position of a rotatable object 11 , in which the method according to the invention can be used. The position measuring device 10 includes a first sensor 1 for generating a first sensor signal C. and one along the object's trajectory 11 compared to the first sensor 1 Second sensor arranged offset by a predetermined distance, here angular distance 2 for generating a second sensor signal S. having. The sensors 1 , 2 the position measuring device 10 are arranged offset by an angular distance of 90 ° and can, for example, be designed as magnetic field sensors that generate a magnetic field of the object 11 detect. For example, the magnetic field sensors can be designed as Hall sensors or GMR sensors that are based on the effect of the giant magnetoresistance. The object 11 can have exactly one magnet with exactly one north pole and exactly one south pole. Alternatively it is possible that the object 11 comprises several magnets, so that a multi-pole arrangement with alternately arranged north poles and south poles on the object 11 is available.

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

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

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

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

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

In the case of conditions in which a non-sinusoidal magnetic field is present or the sensors have a non-linearity, it is, however, necessary to use the position measuring device 10 to calibrate in a calibration process, an assignment of a combination of the first sensor signal C. and the second sensor signal S. to a rotation angle specification y of the object 11 is determined. According to the invention, this calibration process can be carried out without the need for a reference sensor to detect the rotation angle information γ is required. Rather, it is possible to use the assignment alone when moving the object 11 obtained sensor signals.

For the position measuring device after 1 an evaluation unit is provided which can either be operated in a calibration mode in order to carry out a calibration process 100 perform, or in a measurement mode to perform a measurement 101 perform. This fact is in 1 through two blocks 100 , 101 shown, between which by means of several switches 102 can optionally be switched back and forth. In the calibration process 101 is therefore an assignment of a combination of the first sensor signal C. and the second sensor signal S. for a position specification γ of the object 11 determined and in the measuring process 101 is based on the calibration process 100 determined assignment and the first and the second sensor signal a position information γ of the object 11 certainly.

According to a modification of the in 1 embodiment shown can be on the switch 102 be waived. With such a modification, the evaluation unit is operated in such a way that a calibration process is carried out at the same time 100 and a measurement process 101 be performed. 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 shows a first course over time 3 of the first sensor signal C. and a second time course 4th of the second sensor signal S. as they are as part of the calibration process 100 can be captured. Thereby the object 11 over the entire working range of the position measuring device 10 emotional. In the present case a position measuring device 10 for determining a rotational position of the rotatable object 11 , the object becomes 11 by a complete revolution, ie rotated by 360 °. The first sensor signal from the first sensor 1 and the second sensor signal S. of the second sensor 2 saved together with the respective time values. For example, these time courses 3, 4 can each be 1000 points in time consisting of a value of a sensor signal C. , S. and the associated fair value. An exemplary table with such measured values from a calibration process is shown in FIG 6 shown.

The amplitudes of the first sensor signal are typical C. and the second sensor signal S. essentially identical. Should the amplitudes of the first sensor signal C. and the second sensor signal S. differ from each other, a comparison of the amplitudes of the first and second sensor signals can first be carried out C. , S. respectively. With such a comparison, a gain and / or an offset of the first and second sensor signals can be achieved C. , S. set so that both sensors 1 , 2 the amplitude, or the maximum and the minimum, are essentially identical. In addition, outliers caused by high-frequency interference can be smoothed using a smoothing process.

As an alternative to the in 6 shown table with measured values, the time courses 3, 4 can be approximated as a function over time in order to add additional values between that in the table 6 times shown.

As shown in 2 It can also be seen that the time profiles 3, 4 are not ideal sinusoidal profiles, but rather have deviations from the ideal sinusoidal shape. The completion of a rotation of the object 11 around 360 ° can be determined by making a comparison between a current pair of values of the first sensor signal C. and the second sensor signal S. with a stored value pair of the first sensor signal C. and the second sensor signal S. is carried out. The stored value pair is preferably a value pair stored at the beginning of the calibration process.

Starting from the first and second course 1 , 2 of the sensor signals C. , S. several time pairs are determined, each with a first time of the first profile and a second time of the second profile. The first and second points in time of a point in time pair are selected in such a way that the first sensor signal C. by doing first point in time essentially the second sensor signal S. in the second point in time. Thus, these time pairs define time intervals between the beginning and end of which the object is located 11 exactly by the angular distance between the first and second sensor 1 , 2 turned. The number of time pairs can be freely selected. In the present example after 2 a total of 29 such time pairs are formed, which can also be understood as a time interval.

The selection of the time pairs is preferably made based on 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 with changes over time. The point in time pairs are therefore preferably selected such that their first and second points in time do not lie in the ranges of the maxima and minima. Furthermore, it is preferred if all time pairs form time intervals which lie completely within one revolution of the working area, here one revolution through 360 °. In the present exemplary embodiment, the last, here time pair, is used 329 chosen such that the second point in time of this point in time pair is a value pair from the first and second sensor signal C. , S. which is essentially identical to the pair of values from the first and second sensor signals C. , S. in the first point in time of the first point in time pair.

The representation in 7th shows an exemplary table with measured values for a total of 72 time 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. for a position specification of the object 11 is now based on the specific time pairs and additionally based on the specified angular distance A. , here 90 °, of the first and second sensor 1 , 2 , determined. In this case, an equation system with n equations is formed in the calibration process, which has an equation of the form at each point in time $${\gamma }_{n\mathrm{,\; 2}}-{\gamma }_{n\mathrm{,1}}=\mathrm{A.}$$

includes, where γ _{n, 1} a first position specification in the first point in time of the n-th point in time pair and γ _{n, 2} a second position specification in the second point in time of the nth point in time pair and A denotes the predetermined distance of the first sensor 1 and second sensor 2 is.

In this respect, an equation system with n equations and 2n unknowns is initially obtained. In order to enable this system of equations to be solved, the number of unknowns is reduced. To reduce unknowns in the equation system, at most half of the first position information is used γ _{n, 1} replaced by an approximate value which is dependent on at least two further first position information γ _n-1,1 , γ _{n + 1,1} and at most half of the second position information γ _{n, 2} is replaced by an approximate value that is dependent on at least two further second position details γ _n-1,2 , γ _{n + 1,2} . In the present exemplary embodiment, every second one of the first position information γ _{n, 1} replaced by a first approximate value and every second of the second position information is replaced by a second approximate value.

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

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

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

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

surrendered $${\gamma }_n=e_n\cdot {\gamma }_{n-1}+f_n\cdot {\gamma }_{n+1}$$

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

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

By replacing half of the first and second position information γ _{n, 1} , γ _{n, 2} the number of unknowns in the equation system is halved by the approximate values described above. The equation system 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 Gaussian algorithm.

According to a deviation from the method steps explained above for determining an approximate value of a first position specification γ _{n, 1} the approximate value can be dependent on at least three, preferably four, further first position information. Correspondingly, a second position specification can be used to determine an approximate value 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 equation system is optionally possible. For this purpose, a first point in time, that is to say a start point in time, of a first point in time pair can be selected such that it coincides in time with a second point in time, that is to say an end point in time, of a second point in time pair. A first example of such a selection of time pairs is shown in FIG 2 shown. The first points in time are the point in time pairs or intervals 219 and 220 identical to the second points in time of the point in time pairs or intervals 214 and 215 . Another example of such a selection is in 4th shown. According to 4th are the times of three time pairs 301 , 306 , 311 seamlessly attached to each other. This is the second point in time of a first point in time pair 301 chosen such that it corresponds to the first point in time of a second point in time pair 306 coincides and the first point in time of a third point in time pair 311 is chosen such that it begins with the second point in time of the second point in time pair 306 coincides.

If the time pairs are partially defined contiguous to one another, as shown in 4th is shown, it is possible to replace less than half of the first and second position information with a corresponding approximate value. 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, which is dependent on at least two further second position information.

Finally, the system of equations with n equations is solved in order to determine the maximum n unknowns. These unknowns are the position information γ _{n, 1} , γ _{n, 2} . This position information γ _{n, 1} , γ _{n, 2} are through the first course 1 and the second course 2 each assigned to a point in time t _n and can thus each be a combination of the first sensor signal C. and the second sensor signal S. be assigned. A table with such an assignment of a combination of the first sensor signal C. and the second sensor signal S. for a position specification y of the object 11 is in 8th shown.

In order to obtain a continuous assignment, an interpolation algorithm is used in the calibration process, which continuously assigns the combination of the first sensor signal C. and the second sensor signal S. to the position specification y of the object 11 determined. A graphic representation of such a continuous association between the combination of the first sensor signal C. and the second sensor signal S. for a position specification y of the object 11 is in 5 shown.

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

List of reference symbols

1

sensor

2

sensor

3

temporal course

4th

temporal course

10

Position measuring device

11

object

100

Calibration process

101

Measuring process

201-227

Time pair

301-315

Time pair

A.

distance

B.

amplitude

C.

Sensor signal

S.

Sensor signal

γ _{n, 1}

Position information

γ _{n, 2}

Position information

γ

Position information

Claims (10)

Method for determining a position specification (y), in particular a rotation 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 object (11) with respect to 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 an assignment of a combination of the first sensor signal (C) and the second sensor signal (S) to a position indication (y) of the object (11 ), in particular an indication of the angle of rotation of the object (11), is determined and a position indication (y) of the object (11) is determined in a measuring process following the calibration process based on the determined assignment and the first and second sensor signals (C, S), characterized in that, to determine the assignment in the calibration process, the object (11) is moved relative to the first and second sensors (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) is determined, and several pairs of times (201-227, 301-315) with a first time of the first curve (3) and a second Point in time of the second curve (4), the first sensor signal (C) in the first point in time essentially corresponding to the second sensor signal (S) in the second point in time, the assignment based on the determined point in time pairs (201-227, 301-315 ) is determined. Procedure according to Claim 1 , characterized in that the assignment in the calibration process is additionally determined on the basis of the predetermined distance (A), in particular the predetermined angular distance. Method according to one of the preceding claims, characterized in that an equation system with n equations is formed in the calibration process, which equation of the form at each time pair (201-227, 301-315) $${\gamma }_{n\mathrm{,\; 2}}-{\gamma }_{n\mathrm{,1}}=\mathrm{A.}$$

comprises, where γ _{n, 1} denotes a first position specification in the first point in time of the n-th point in time pair and γ _{n, 2} denotes a second position information in the second point in time of the n-th point in time pair and A is the predetermined distance between the first and second sensors. Procedure according to Claim 3 , characterized in that, 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 a first approximate value that 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 by a second approximate value which is dependent on at least two further second position information. Procedure according to Claim 4 , characterized in that the approximate value is a linear approximate value. Method according to one of the Claims 4 or 5 , characterized in that the approximate value is dependent on at least three, preferably at least four further first position information. Method according to one of the Claims 3 to 6 , characterized in that at least a first and a second of the time pairs (204, 205, 209, 210, 301-315) are selected to reduce unknowns in the equation system such that the second time of the first time pair is identical to the first time of the second time pair. Method according to one of the Claims 3 to 7th , characterized in that the equation system is solved in order to determine unknowns of the equation system, 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 course (3, 4). Method according to one of the preceding claims, characterized in that a continuous assignment of a combination of the first sensor signal (C) and the second sensor signal (S) to a position indication (y) of the object (11) is determined in the calibration process by means of an interpolation algorithm.

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