DE102009019183B4 - Interpolation method for bridging the free-running phase of a setting process - Google Patents

Abstract

Method for determining parameters (a, b, c, d, e, f, g) of an interpolation function (F), which as a function of a number of characteristic variables as interpolation result (Δy) is a measure of the within the freewheeling phase (21) of a positioning process The characteristic variable determines the time interval (x1) between the last current ripple (r-1) of the motor current before the freewheeling phase (21) and the first current ripple (r1) of the motor current after the freewheeling phase (21) and at least one time interval (x2, x3, x4) between two of the freewheeling phase (21) preceding and / or two of the freewheeling phase (21) subsequent current ripples (r-3, r-2, r-1, r1, r2) of the motor current, wherein according to the method - by means of at least one reference setting device (1 ') a multiplicity of reference setting operations are carried out, - one reference for each reference setting process and each characteristic variable erenz amount is determined, - a measured value (Δy ') of the travel distance traveled within the respective free-wheeling phase (21) is detected for each reference setting process independently of the motor current, and - the parameters (a, b, c, d, e, g) of the interpolation function (F) are determined in such a way that the squared error of the interpolation result (.DELTA.y) is compared by taking into account the reference amounts detected for a selection of reference setting operations and the respectively associated measured value (.DELTA.y ') by means of an optimization algorithm is minimized to the measured value (Δy ') in total via the selection of reference setting operations.

Description

The invention relates to a method for determining the setting position of a motor-driven adjusting device for a motor vehicle by means of an interpolation function, which determines a measure of the traversed within the freewheeling phase of a positioning process in dependence on a number of characteristic variables of the time course of a motor current. The invention further relates to a method for determining parameters of such an interpolation function as well as to a setting device operating according to the first-mentioned method.

In a modern motor vehicle, a plurality of motor control devices are usually present. Such an adjusting device is, for example, an electric window, an electric seat adjustment or a device for the motorized adjustment of a vehicle door, a tailgate, a sunroof or a Caprioverdecks.

As part of a setting operation of such a setting often a desired end position must be approached precisely. For this purpose, a precise knowledge of the positioning position of the adjusting device is required. The knowledge of the current parking position, or derived therefrom variables such as the actuating speed or the traversed travel are also often required for the secure detection of a trapping case.

An adjusting device of the above type is often operated by a mechanical commutated direct current motor (commutator). In such a control device, the setting position can be determined by counting the so-called motor current ripple. As a (motor) current ripple here is a characteristic ripple (that is, periodic, pulse-like fluctuation) of the motor current referred to, which is caused by the commutation of the DC motor.

However, the counting of the current ripple is not possible without errors over the entire length of a typical setting process. Thus, a typical setting process is divided into an initial start-up phase, an equilibrium phase (steady state), a freewheeling phase and a final braking phase.

During the start-up phase, the motor speed oscillates at a stable final speed. In the subsequent equilibrium phase, this terminal velocity and thus also the frequency of the current ripple are approximately constant. The freewheeling phase is initiated by the fact that both connections of the commutator motor are switched to ground to complete the adjustment process. The freewheeling phase extends over the duration of this switching operation including a switching-related bounce phase and typically takes about 3 to 4 ms. Due to the switching operation flows in the freewheeling phase - with substantially unchanged positioning speed of the motor - no or only extremely irreproducible motor current. As soon as both motor contacts are stable connected to ground, the freewheeling phase goes into the final braking phase. In the braking phase of the short-circuited to ground electric motor is operated as a generator and braked by the circulating current thus generated.

Due to the collapsing motor current counting the current ripple in the freewheeling phase is not possible. In order nevertheless to be able to precisely determine the setting position over the freewheeling phase, the development of the setting position during the freewheeling phase is often determined by interpolation.

As a rule, the interpolation functions used for this purpose simulate the physical behavior of the actuating device during the freewheeling phase. They therefore usually depend on a number of parameters having a concrete physical meaning. For example, such parameters characterize the mechanical inertia of the drive system of the actuator or a coefficient of friction. Such parameters must be determined individually for each individual setting device due to production-related differences. Adjustment devices that use such interpolation methods are therefore usually individually trained, which causes a significant overhead in the assembly and commissioning of the control devices in a motor vehicle.

In addition, such parameters depend in part in turn on other conditions, such as the ambient temperature or the age of the actuator. Disadvantageously, the consideration of these conditions leads to a high complexity of conventional interpolation methods, and to correspondingly high requirements for the hardware performing such a method. On the other hand, a simplification of conventional interpolation methods by disregarding certain conditions generally leads, in some cases, to not inconsiderable errors of such an interpolation method.

A method of determining the travel using such an interpolation function is, for example, off EP 0 997 341 B1 known.

Out DE 100 28 037 A1 Furthermore, a method for determining the rotational position of the drive shaft of a DC motor by evaluating the current ripple contained in the armature current signal is known, in which in the case of an interruption of the electrical connection between the DC motor and the evaluation an approximate determination of the amount traveled during the outlet of the armature of the DC motor angle of rotation Determination of the number of expected ripples expected during this phase.

The object of the invention is to improve the interpolative determination of the travel path (freewheel travel path) traveled by a motor vehicle adjusting device during the freewheeling phase of a setting process, with a view to simple feasibility and at the same time high fault tolerance.

The invention is based on a method in which the freewheeling travel path is determined by means of an interpolation function which depends on a number of characteristic variables (ie at least one characteristic variable) of the time profile of a motor current quantity and on a number of parameters (ie at least one parameter), and outputs a measure of the freewheeling travel as an interpolation result.

With regard to a method for determining the parameters of this interpolation function (optimization method), the above object is achieved according to the invention by the features of claim 1. Thereafter, it is provided to first carry out a multiplicity of reference setting operations by means of a reference setting device. For each of these reference actuating processes, the time profile of the motor current variable is detected, and from this a reference value is determined for each characteristic variable of the interpolation function. In addition, a measured value for the respective freewheeling travel is recorded for each reference setting process. This measured value is measured independently of the motor current size, ie. H. such that it is neither influenced by the size of the motor current nor influences it. The parameters of the interpolation function are determined by means of an optimization algorithm, taking into account the reference values of the characteristic variable and the respective associated measured value which are detected for a selection of reference setting operations.

The term "motor current quantity" generally designates any current magnitude or voltage magnitude of the motor current which permits a statement about the operating state of the actuating device, in particular a count of motor current ripples. The motor current magnitude is preferably the so-called mutual induction voltage (also counterelectromotive force). Furthermore, however, the current intensity of the motor current or the self-induction component of the motor voltage can also be used as the motor current quantity.

• – einen Spannungs- bzw. Stromstärkewert, den eine vorgegebene Motorstromgröße an einer vorgegebenen Position oder zu einem vorgegebenen Zeitpunkt innerhalb eines Stellvorgangs annimmt, z. B. um den Betrag der Motorstromstärke zu Beginn der Freilaufphase,
• – einen Zeitpunkt, zu dem die Motorstromgröße ein charakteristisches Verhalten zeigt, insbesondere um den Zeitpunkt, zu dem ein bestimmter Stromrippel – z. B. der letzte Stromrippel vor der Freilaufphase – innerhalb der Motorstromgröße auftritt, oder
• – um eine Differenz zwischen zwei solchen Stromstärke- bzw. Spannungswerten oder zwei solchen Zeitpunkten.

Bevorzugt werden hierbei als Kennvariablen die zwischen zwei bestimmten Stromrippeln auftretenden Zeitintervalle herangezogen, wobei die Stromrippel wiederum bevorzugt aus dem Verlauf der Gegeninduktionsspannung ermittelt werden. Grundsätzlich kann die Interpolationsfunktion aber auch von verschiedenartigen Kennvariablen, insbesondere von Kennvariablen unterschiedlicher Motorstromgrößen abhängen.The term "variable" generally refers to

• A voltage or current value which a predetermined motor current quantity assumes at a predetermined position or at a predetermined time within a setting process, e.g. B. by the amount of motor current at the beginning of the freewheeling phase,
• A time when the motor current magnitude shows a characteristic behavior, in particular at the time at which a certain current ripple - z. B. the last current ripple before the freewheeling phase - occurs within the motor current magnitude, or
• By a difference between two such current or voltage values or two such times.

In this case, the time intervals occurring between two specific current ripples are preferably used as characteristic variables, the current ripples in turn preferably being determined from the profile of the mutual induction voltage. In principle, however, the interpolation function can also depend on various characteristic variables, in particular characteristic variables of different motor current variables.

The characteristic variables are those variables of the interpolation function that generally vary from setting process to setting process. In contrast to this, the "parameters" of the interpolation function are those variables or numerical values which are assigned to the interpolation function for the operation of the actuating device as constants, which therefore have the same value for all actuating processes of the actuating device.

The "measure" output as an interpolation result is generally of any size from which the free-wheeling travel is derivable. In an expedient embodiment, this measure gives the number of current ripples again, which would have been expected according to the engine rotation during the freewheeling phase. This execution of the interpolation function makes it possible to use the interpolation result without further conversion as a correction variable for the current ripple counting.

The term "control device" (hereinafter also referred to as "operating control device" for clarity) designates an actuating device that is actually intended for use in a vehicle or installed in a vehicle. In contrast, the or each "reference actuator" is a separate experimental set-up, for example, being stationary in a laboratory, and which is more or less a prototype of the operational controls intended for practical use. According to this nomenclature, positioning operations performed by means of the reference actuator are referred to as reference operations. Furthermore, the amount of a characteristic variable, which is determined for a reference setting process, referred to as a reference amount.

The or each reference setting device is at least substantially identical in construction to the or each operating setting device, but differs from the latter in that the or each reference setting device is assigned the additional measuring arrangement for detecting the measured value of the free-running travel. Also, this measured value is generally any information from which the freewheeling travel is derivable. However, the measured value is expediently generated in such a way that it is directly comparable to the result of the interpolation.

An "optimization algorithm" is generally an arbitrary (analytical or numerical) mathematical algorithm, by means of which the interpolation function is parameterized in such a way that the interpolation result for the considered selection of reference actuating processes is optimally adapted to the associated measured values of the freewheeling travel path. In the case of the optimization algorithm, this is preferably a method in which the squared error of the interpolation result is minimized in comparison with the measured value in total via the selection of reference setting processes, in particular the so-called Gauss-Newton method or the so-called Levenberg -Marquardt algorithm. The term "selection" is to be understood as meaning that preferably all recorded reference setting processes are taken into account in the optimization, but that individual reference setting processes, in particular "outliers", can also be disregarded in the optimization.

The invention is based on the idea of not separately determining the parameters of an interpolation function bridging the freewheel phase as customary for each operating control device by means of individual teach-in, but of specifying them universally for all operating control devices. As is known, the elimination of this individual teach-in process results in a substantial simplification in the assembly and commissioning of the operating control devices. By the optimization method according to the invention for parameterizing the interpolation function, a precise mode of operation of these operating control devices is ensured despite the absence of individual teaching-in of the operating control devices.

In an advantageous embodiment of the method, the time interval between the last current ripple before the freewheeling phase and the first current ripple after the freewheeling phase and at least one further time interval between two freewheeling phase preceding current ripples and / or two of the freewheeling phase following current ripple are used as characteristic variables of the interpolation function. As is known, the use of these time intervals as characteristic variables makes possible an extremely precise calculation of the freewheeling travel path on a purely phenomenological basis. In the context of the interpolation function, therefore, no assumptions have to be made about the physical properties of the setting device or about the physical influence of environmental conditions on the setting device. Rather, by the optimization process, both production-related differences between individual operating control devices and the influence of different environmental conditions are implicitly taken into account insofar as such production-related differences and environmental conditions, as is known, characteristically influence the time intervals between the current ripples in the temporal environment of the free-wheeling phase. Expressed in clear terms, the time intervals between the current ripples in the temporal environment of the freewheeling phase are used as a kind of "fingerprint" for identifying the operating situation of the adjusting device and for determining the freewheeling travel path corresponding to this operating situation.

erwiesen. Hierhin bezeichnen Δy das Interpolationsergebnis, und x₁ bis x₄ folgende Kennvariablen:

• – x₁: Zeitintervall zwischen dem letzten Stromrippel vor der Freilaufphase und dem ersten Stromrippel nach der Freilaufphase
• – x₂: Zeitintervall zwischen dem ersten und zweiten Stromrippel nach der Freilaufphase
• – x₃: Zeitintervall zwischen dem zweitletzten und letzten Stromrippel vor der Freilaufphase
• – x₄: Zeitintervall zwischen dem drittletzten und zweitletzten Stromrippel vor der Freilaufphase

Particularly advantageous here is the use of an interpolation function of the form

proved. Here, Δy denote the interpolation result, and x ₁ to x _{4 the} following characteristic variables:

• - x ₁ : Time interval between the last current ripple before the freewheeling phase and the first current ripple after the freewheeling phase
• X ₂ : time interval between the first and second current ripple after the freewheeling phase
• - x ₃ : time interval between the second last and last current ripple before the freewheeling phase
• X ₄ : Time interval between the third last and second last current ripple before the freewheeling phase

The quantity θ = (a, b, c, d, e, f, g) denotes a set of parameters a, b, c, d, e, f, g. These parameters are not quantities with a concrete physical meaning, but rather phenomenological numbers (floating-point numbers), which are determined empirically in the course of the optimization process.

• – unterschiedliche Umgebungstemperatur,
• – unterschiedliche Luftfeuchtigkeit,
• – unterschiedliche Last, d. h. unterschiedlichen mechanischen Widerstand gegen die Stellbewegung,
• – unterschiedliche Betriebsspannung (z. B. Fahrzeugbatteriespannung), insbesondere innerhalb eines Stellvorgangs schwankende Betriebsspannung
• – unterschiedliche Standzeit, d. h. unterschiedliche Zeitintervalle zwischen zwei Stellvorgängen und/oder
• – unterschiedliches Betriebsalter der Referenz-Stelleinrichtung, insbesondere unterschiedliche Anzahl von vorausgegangen Stellvorgängen.

In a preferred embodiment of the optimization method, the reference setting processes are carried out selectively at least partially under different operating conditions. The varied in the implementation of the reference setting operations operating conditions are characterized in particular

• Different ambient temperature,
• - different humidity,
• Different load, ie different mechanical resistance to the adjusting movement,
• - Different operating voltage (eg., Vehicle battery voltage), in particular within a control operation fluctuating operating voltage
• - Different life, ie different time intervals between two actuations and / or
• - Different operating age of the reference setting device, in particular different number of previous settlements.

Expediently, with regard to one or more of these operating conditions, a range of fluctuations to be expected in normal operation is scanned completely. For example, for a window lift preferably in steps of z. B. 5 ° C reference setting operations at any ambient temperature (inside the vehicle door) between -30 ° C and 80 ° C recorded.

The counterinduction voltage preferably used as the motor current quantity is that voltage component of the motor voltage which is generated by magnetic interaction between the stator and rotor of the servomotor of the actuating device when the rotor rotates. As is known, current ripple can be detected particularly fail-safe from the mutual induction voltage. The mutual induction voltage is determined in an expedient embodiment of the method by means of a numerical motor model from the motor current and the operating voltage.

The measured value of the freewheeling travel is preferably detected by means of a Hall sensor associated with the reference actuator. The Hall sensor acts together with a ring magnet, which is coupled to a drive shaft of the reference actuator.

The number of poles of the ring magnet is preferably selected such that it is an integer multiple n (where n = 1, 2, 3,...) Of the number of current ripples of the motor current magnitude per full motor rotation. In this way, the signal generated by the Hall sensor per motor full rotation on a number of edge changes, which is an integer multiple n (where n = 1, 2, 3, ...) of the current ripple number. The signal of the Hall sensor and the result of the interpolation are therefore particularly easy to compare.

The above object is further achieved according to the invention by a method for determining the setting position of a motorized adjusting device for a motor vehicle (interpolation method), in particular for determining the freewheeling travel, with the features of claim 8. In the course of this method is provided, in a temporal environment of the freewheeling phase a setting process to detect the time course of the motor current magnitude, to determine from this course the respective amount of each characteristic variable of the interpolation function described above and to determine the measure of the freewheeling travel by means of the interpolation function as a function of the characteristic variables as interpolation result. The parameters of the interpolation function are determined according to the optimization method described above in one of its variants.

The above object is also achieved according to the invention by an adjusting device for a motor vehicle, with an electric servomotor and with a control unit for controlling the servomotor, wherein the control unit for implementing the interpolation method described above, d. H. is formed program and / or circuit technology.

The control unit is in particular formed by a microcontroller or comprises at least one such, wherein the interpolation method is implemented by software in the context of a control program in this microcontroller.

An embodiment of the invention will be explained in more detail with reference to a drawing. Show:

1 in a schematic block diagram of a motor-driven actuating device for a motor vehicle, here a window regulator, with a servomotor and with a control unit for controlling the same,

2 in a schematic diagram against time a typical course of the mutual induction voltage of the servomotor during the equilibrium phase, the freewheeling phase and the braking phase of a parking operation, and, derived from the mutual induction voltage current ripple signal,

3 in a schematic block diagram of a part of a in the control unit according to 1 implemented control program for determining the parking position with determination of the freewheeling travel by means of an interpolation function,

4 in illustration according to 1 a reference setting device for determining the parameters of the interpolation function, and

5 in a schematic block diagram in accordance with the control unit 4 implemented optimizer for parameter determination.

Corresponding parts and sizes are always provided with the same reference numerals in all figures.

1 shows an (operating) adjusting device 1 , which is installed in a motor vehicle. At the operating control device 1 is an example of an electric window for adjusting a vehicle window 2 , The adjusting device could alternatively also be an electric seat adjustment or a motorized setting device for a sliding roof, a vehicle door or the like.

The adjusting device 1 includes an electric servomotor 3 in the form of a commutator motor, via an actuating mechanism 4 such with the vehicle window 2 is coupled to the vehicle window 2 through the servomotor 3 within a control range 5 reversible between two end positions, namely an open position 6 and a closed position 7 , is movable.

The adjusting mechanism 4 includes in particular one with a rotor of the servomotor 3 coupled drive shaft 8th that have a gearbox 9 on the vehicle window 2 acts. The adjusting device 1 further comprises a control unit formed by a microcontroller 10 , The control unit 10 acts on relays 11 and 12 , with which the two motor connections of the servomotor 3 reversible between an operating voltage U _b and ground M can be switched. The operating voltage U _b is, in particular, the battery voltage of the motor vehicle.

The control unit 10 On the input side, measured values I ₁ and I _{2 are} supplied to the motor current intensity. These measured values I ₁ and I ₂ are from ammeters 13a and 13b detected, each one of the relay 11 respectively. 12 and ground M are interposed, and thus measure the strength of the outgoing from the respective motor terminal to ground M stream. At the power knives 13a and 13b In the simplest case, these are measuring resistors. In this case, the voltage across the measuring resistors - voltage proportional to the current - is used as measured value I ₁ or I ₂ . Alternatively, the power meters 13a and 13b also be formed by current transformers. The control unit 10 Furthermore, the operating voltage U _b or a measured value proportional thereto is supplied.

In the control unit 10 is a control program 14 implemented by software. This control program 14 On the one hand controls by wiring the relay 11 and 12 the servomotor 3 for performing parking operations, in the course of which the vehicle window 2 towards their open position 6 or towards their closed position 7 is moved.

In the course of each setting, the control program calculates 14 on the other hand from the supplied measured values I ₁ and I ₂ and from the measured operating voltage U _b, the mutual induction voltage U _befm and determines from this the current setting position z of the operating control device 1 ,

A typical course of the mutual induction voltage U _befm during a _setting operation of the operating _actuator 1 is in 2 plotted against the time t in a diagram. In 2 In addition, a _ripple signal R derived from the mutual induction voltage U _bem is shown. The ripple signal R corresponds essentially to the mathematical time derivative of the mutual induction voltage U _bemf , with long-wave components of the mutual induction voltage U _bemf in the ripple signal R being filtered out.

2 it can be seen that in an equilibrium phase 20 of each setting process in which the servomotor 3 moved at a substantially constant actuating speed, the mutual induction voltage U _{bemf has} a uniform sequence of current ripples. The equilibrium phase 20 is terminated by that by the control unit 10 with corresponding switching of the relays 11 and 12 Both motor connections are connected to ground M. The period of time taken up by this switching process, including the bounce phase that concludes the switching process, denotes a so-called free-wheeling phase 21 of the adjustment process. As soon as both motor connections are connected to ground M, the freewheeling phase starts 21 in a braking phase 22 over, in which the servomotor 3 over mass M generates a circulating current. As 2 can be seen, even in the braking phase 22 the mutual induction voltage U _bemf and the ripple signal R are metrologically detected. In contrast, the actuator is 3 in the freewheeling phase 21 from the power supply, and thus in particular from the ammeters 13a and 13b decoupled. This allows in the freewheeling phase 21 neither the mutual induction voltage U _bemf nor the ripple signal R are determined.

The control program 14 generally determines the setting position z by counting the current ripple occurring during the setting process within the ripple signal R. During the free-running phase 21 traversed (freewheel) travel, which can not be taken into account in the ripple count, is from the control program 14 thereby determined interpolatively.

aus den der Steuereinheit 10 zugeführten Messwerten I₁ und I₂ ermittelt. Das Motormodell 23 berechnet die Gegeninduktionsspannung U_bemf hierbei anhand einer numerischen Motormodellgleichung der Form

worin R den Ankerwiderstand, und L die Selbstinduktivität des Stellmotors 3 bezeichnen. Beide Größen sind dem Motormodell 23 als Konstanten vorgegeben.To carry out this interpolation method, the control program comprises 14 according to 3 on (hereinafter referred to as motor model 23 denoted) software _{module which} determines the mutual induction voltage U _bemf from a measured value I of the motor current intensity and a measured value of the operating voltage U _b . The measured value I of the motor current is here, for example, according to the formula

from the control unit 10 supplied measured values I ₁ and I ₂ determined. The engine model 23 calculates the mutual induction voltage U _bemf herein with reference to a numerical motor model equation of the form

where R is the armature resistance, and L is the self-inductance of the servomotor 3 describe. Both sizes are the engine model 23 given as constants.

From the mutual induction voltage U _bemf be in a downstream filter module 24 , which is essentially a numerical low-pass filter, low-frequency components filtered out. The module 24 producing as an output the ripple signal R, the _bemf the high frequency components of the mutual induction voltage U, and thus contains the information about the occurrence of the current ripple.

The ripple signal R is subsequently used as a ripple detector module 25 supplied software module. The rib detector module 25 The ripple signal R continuously examines the occurrence of current ripples and outputs a detection pulse S whenever a current ripple is detected. The rib detector module 25 detects the occurrence of a current ripple in the simplest case by comparing the ripple signal R with a stored threshold, and it outputs the detection pulse S when the amount of the ripple signal R exceeds the threshold. In order to be able to reliably distinguish current ripples from possible disturbances of the ripple signal R, the ripple detector checks 25 optionally in addition one or more further conditions, in particular whether the time derivative of the ripple signal R is within predetermined limits and / or whether the time length of the current ripple, so the period for which the amount of the ripple signal R exceeds the tripping threshold, is within predetermined limits. In this case, the rib detector module generates 25 the detection pulse S only and only if all tested conditions are met.

The detection pulse S becomes a downstream ripple counter module 26 , and on the other hand, a ripple distance detection module 27 fed. In the ripple counter module 26 the current ripples detected during the setting process are counted. The rib counter 26 In this case, it increments a counter reading whenever it receives the detection pulse S. After completion of the adjustment, the ripple counter module outputs 26 the detected Rippelanzahl y as a measure of the traversed during the adjustment process travel.

• – als Kennvariable x₁ das Zeitintervall zwischen dem letzten Stromrippe) r_–1 (2) vor der Freilaufphase 21 und dem ersten Stromrippel r₁ (2) nach der Freilaufphase 21,
• – als Kennvariable x₂ das Zeitintervall zwischen dem ersten Stromrippel r₁ (2) und dem zweiten Stromrippel r₂ (2) nach der Freilaufphase,
• – als Kennvariable x₃ das Zeitintervall zwischen dem letzten Stromrippel r_–1 (2) und in dem zweitletzten Stromrippel r_–2 (2) vor der Freilaufphase 21, sowie
• – als Kennvariable x₄ das Zeitintervall zwischen dem zweitletzten Stromrippel r_–2 (2) und dem drittletzten Stromrippel r_–3 (2) vor der Freilaufphase 21

und übermittelt diese Kennvariablen x₁ bis x₄ an ein nachgeschaltetes Interpolationsmodul 28, in dem die Interpolationsfunktion F gemäß Glg. 1 implementiert ist.In the ripple distance detection module 27 the time duration between each two directly consecutive current ripple, ie the time between each two detection pulses S is detected. The detected time intervals are determined by the ripple interval detection module 27 - For example, in a shift register - cached. After completion of the setting process, or at least after completion of the freewheeling phase 21 , determines the ripple distance detection module 27 based on the cached time intervals

• As characteristic variable x ₁ the time interval between the last current ridge) r _-1 ( 2 ) before the freewheeling phase 21 and the first current ripple r ₁ ( 2 ) after the freewheeling phase 21 .
• As characteristic variable x _2, the time interval between the first current ripple r ₁ ( 2 ) and the second current ripple r ₂ ( 2 ) after the freewheeling phase,
• As characteristic variable x _3, the time interval between the last current ripple r _-1 ( 2 ) and in the second last current ripple r _-2 ( 2 ) before the freewheeling phase 21 , such as
• As characteristic variable x ₄ the time interval between the second last current ripple r _-2 ( 2 ) and the third last current ripple r _-3 ( 2 ) before the freewheeling phase 21

and transmits these identification variables x ₁ to x ₄ to a downstream interpolation module 28 in which the interpolation function F according to Eq. 1 is implemented.

The interpolation module 28 calculated by inserting the characteristic variable x ₁ to x ₄ and the predetermined parameter set θ as interpolation result .DELTA.y the number of current ripples whose occurrence during the freewheeling phase 21 would have been expected.

The from the ripple counter module 26 determined ripple number y and the interpolation result .DELTA.y are a Stellpositionsermittlungsmodul 29 supplied, which updated based on this information, the current parking position z continuously. The one from the rib counter 26 determined ripple number y is in this case corrected after each setting process by the interpolation result Δy: z _new = z _old + D · (y + Δy) Eq. 4

In the above equation, the variable D symbolizes a direction indicator having the value +1 when the vehicle window 2 upwards, ie in the direction of the closed position 7 is moved, and which has the value -1 when the vehicle window 2 downwards, ie towards the open position 6 is moved.

The information about the parking position z is in the course of the tax procedure 14 used to the vehicle window 2 in good time before reaching the closed position 7 or opening position 6 decelerate. The vehicle window 2 In this case, in particular, it is braked in such a way that it is already at a lower limit of the setting range shortly before the stop on the upper window seal or before the stop 5 comes to a halt to the mechanical components of the actuating mechanism 4 to protect. The knowledge of the parking position z is also for one in the context of the control program 14 furthermore provided anti-pinch algorithm required.

The parameters a, b, c, d, e, f and g of the parameter set θ are the operating control device 1 fixed. They are for every plant control device 1 universal, so have for each plant actuator 1 always the same values. The determination of these parameters a to g is independent of the individual operating control device 1 by an optimization method described below.

In the course of this optimization procedure, at a reference setting device 1' , in the 4 is shown, a plurality of reference setting operations performed.

At the reference actuator 1' it is a window lift test setup, which is preferably not built in a motor vehicle, but stationary in a laboratory.

The reference actuator 1' includes a servomotor 3 ' , an actuating mechanism 4 ' with a drive shaft 8th' and a gearbox 9 ' , a control unit 10 ' , Relay 11 ' and 12 ' as well as ammunition 13a ' and 13b ' , The reference actuator 1' acts on a vehicle window 2 ' that are within a parking range 5 ' between an open position 6 ' and 7 ' is adjustable. The reference actuator 1' is with the operating control device 1 essentially identical. With regard to the structure and operation of the reference actuator 1' will be referred to in detail on the corresponding statements 1 directed.

In contrast to the operating control device 1 includes the reference actuator 1' but an additional measuring device 30 , which allows a measurement of the actuating position z 'independent of the motor current and of the actuating path traveled within a setting process. The measuring device 30 includes a ring magnet 31 , which is rotationally fixed with the drive shaft 8th' is attached, as well as one with the ring magnet 31 cooperating Hall sensor 32 , The Hall sensor 32 gives a Hall signal U _H to the control unit 10 ' whose time course is schematically in 2 with is offered.

In contrast to the operating control device 1 is within the reference setting facility 1' as a control unit 10 ' Furthermore, preferably no microcontroller, but powerful test computer, in particular a PC, used in which an optimization method described in more detail below in the form of an optimization program 33 software implemented.

• – die Umgebungstemperatur in 5°C-Schritten zwischen –30°C und 80°C,
• – die Luftfeuchtigkeit in der Umgebung der Referenz-Stelleinrichtung 1' in 5%-Schritten zwischen 10% und 100%, und
• – die Betriebsspannung U_b in Schritten von 1 Volt zwischen 7 V und 15 variiert.

The with the reference actuator 1' performed reference settlements are performed such that they cover as fully as possible an expected range of environmental conditions. For example, in the course of the performed reference setting operations

• The ambient temperature in 5 ° C increments between -30 ° C and 80 ° C,
• - The humidity in the vicinity of the reference actuator 1' in 5% increments between 10% and 100%, and
• - The operating voltage U _b in steps of 1 volt between 7 V and 15 varies.

In addition, the weight of the vehicle window and the friction of the actuating mechanism are selectively varied in the course of the reference setting operations. Optionally, a plurality (eg, at least 5,000) of reference actuators are provided with the same reference actuator 1' carried out in order to simulate the influence of increasing age. Optionally, reference setting operations are carried out after a different service life. In addition, the reference setting processes are preferably not limited to a single reference setting device 1' carried out. Rather, the reference setting operations with multiple reference actuators 1' carried out. These can be done in parallel by a common control unit 10 ' be controlled.

Overall, preferably at least 10,000 reference setting operations are performed.

This in 5 detailed optimization program 33 includes some of the same software modules as the one related to 3 described control program 14 , namely in particular the engine model 23 , the filter module 24 , the rib detector module 25 , the ripple distance detection module 27 and the interpolation module 28 ,

In the course of the optimization program 33 The optimization procedure is carried out according to 5 during each reference setting operation by means of the motor model 23 from the measured value I of the motor current and the measured operating voltage U _b, the mutual induction voltage U _bemf calculated. In the downstream filter module 24 In turn, the ripple signal R is generated from the mutual induction voltage U _bemf , from which in turn the rib detector module 25 each detection of a current ripple generates a detection pulse S. In the turn downstream ripple distance detection module 27 In the manner described above, the characteristic variables x ₁ to x _{4 are} determined for each reference setting process. These variables x ₁ to x ₄ are stored in a database 34 stored.

By means of an edge detection module 35 determines the optimizer 33 parallel to this from the Hall signal U _H, the number of (rising and falling) edges of the Hall signal U _H during the freewheeling phase 21 of each reference setting operation and outputs this quantity as measured value Δy '.

In a preferred embodiment of the reference adjusting device 1' has the ring magnet 31 a pole number that is the number of current ripples per full turn of the servomotor 3 ' equivalent. The measuring device 30 thus generates a Hall signal U _H , the per full rotation of the servomotor 3 ' has a number of edges corresponding to the number of current ripples ( 2 ). The from the edge detection module 35 By measuring the edge change determined measured value Δy 'thus corresponds directly to the expected number of current ripple for a given travel. In an alternative embodiment, the ring magnet has 31 a twice the number of poles compared to the number of current ripples per full turn. In this case, the edge detection module counts 35 only the rising edges of the Hall signal U _H.

The measured value Δy ', which thus - as well as the interpolation result Δy - represents a measure of the freewheeling travel, becomes in the database for each reference setting process 34 stored.

In the database 34 For the subsequent optimization process, the reference amounts of the characteristic variables x ₁ to x ₄ and the measured values Δy 'of at least 10,000 reference setting processes are collected.

This data is then an optimization module 36 fed, which performs the actual optimization process.

The optimization module 36 calculated using the interpolation module 28 based on the reference amounts of the characteristic variable x ₁ to x ₄ detected for each reference setting process, the interpolation result Δy, wherein it specifies a default value θ 'for the parameter set θ. Subsequently, the optimization module forms 36 for each reference setting process the error Δy-Δy 'of the interpolation result Δy to the measured value Δy' and sums the squared error difference on: E = Σ (Δy (θ ') - Δy) ² Eq. 5

The size E denotes the total error of the optimization. The sum F preferably runs over all in the database 34 detected reference actuators, but at least via a selection of these reference actuations.

The optimization module 36 iteratively repeats the error summation, minimizing the total error E until a convergence criterion is reached by changing the default value θ '. The optimization module uses this minimization 36 in particular a common error minimization method, in particular the so-called Levenberg-Marquardt algorithm.

Once the convergence criterion is reached, the optimizer breaks 36 the optimization and outputs the last suggested value θ 'as the final parameter set θ. This parameter set θ is then in the control unit 10 the or each operating device 1 for carrying out the related 3 deposited interpolation method.

LIST OF REFERENCE NUMBERS

1

(Operating) actuator

1'

Reference setting device

2, 2 '

vehicle window

3, 3 '

servomotor

4, 4 '

actuating mechanism

5, 5 '

range

6, 6 '

open position

7, 7 '

closed position

8, 8 '

drive shaft

9, 9 '

transmission

10, 10 '

control unit

11, 11 '

relay

12, 12 '

relay

13a, 13a '

ammeter

13b, 13b '

ammeter

14

control program

20

Equilibrium phase

21

Freewheeling phase

22

braking phase

23

engine model

24

filter module

25

Ripple detector module

26

Ripple counter module

27

Rippel distance detection module

28

interpolation

29

Setting position determination module

30

measuring device

31

ring magnet

32

Hall sensor

33

optimization program

34

Database

35

Edge detection module

36

optimization module

θ

parameter set

θ '

default value

Dy

interpolation

Ay '

reading

_i

Current ripple (i = -3, -2, -1, 1, 2)

t

Time

x _i

Kennvariable (i = 1, 2, 3, 4)

y

Rippel number

z, z '

setting position

F

interpolation

I, I ₁ , I ₂

Measured value (the motor current strength)

M

Dimensions

R

ripple signal

S

detection pulse

U _b

operating voltage

U _bemf

Emf

U _H

Hall signal

Claims (8)

Method for determining parameters (a, b, c, d, e, f, g) of an interpolation function (F) which, as a function of a number of characteristic variables as interpolation result (Δy), provides a measure of the value within the freewheeling phase ( 21 ) of a positioning operation traveled a motorized actuating device ( 1 ) is determined for a motor vehicle, wherein the characteristic variables the time interval (x ₁ ) between the last current ripple (r _-1 ) of the motor current before the freewheeling phase ( 21 ) and the first current ripple (r ₁ ) of the motor current after the freewheeling phase ( 21 ) and at least one time interval (x ₂ , x ₃ , x ₄ ) between two of the freewheeling phase ( 21 ) preceding and / or two of the freewheeling phase ( 21 ) comprise downstream current ripples (r _-3 , r _-2 , r _-1 , r ₁ , r ₂ ) of the motor current, according to the method - by means of at least one reference setting device ( 1' ) a plurality of reference setting operations are carried out, - a reference amount is determined for each reference setting process and each characteristic variable, - for each reference setting process, independent of the motor current, a measured value (Δy ') of the within the respective free-running phase ( 21 ), and - the parameters (a, b, c, d, e, f, g) of the interpolation function (F) taking into account the reference amounts detected for a selection of reference manipulations and the respectively associated measured value ( Δy ') are determined by means of an optimization algorithm in such a way that the squared error of the interpolation result (Δy) is minimized in comparison with the measured value (Δy') in total via the selection of reference setting processes. Method according to Claim 1, in which an interpolation function (F) of the form

where Δy denotes the interpolation result, x ₁ to x ₄ denote the following characteristic variables: - x ₁ : time interval between the last current ripple (r _-1 ) before the free-running phase ( 21 ) and the first current ripple (r ₁ ) after the freewheeling phase ( 21 ) - x ₂ : time interval between the first current ripple (r ₁ ) and the second current ripple (r ₂ ) after the free-running phase ( 21 ) - x ₃ : time interval between the second last current ripple (r _-2 ) and the last current ripple (r _-1 ) before the free-running phase ( 21 ) - x ₄ : time interval between the third last current ripple (r _-3 ) and second last ripple (r-2) before the free-running phase ( 21 ), and where θ = (a, b, c, d, e, f, g) denotes a set of parameters a, b, c, d, e, f, g. The method of claim 1 or 2, wherein the reference setting operations are performed at least partially under different operating conditions. The method of claim 3, wherein the different operating conditions different ambient temperature, different humidity, different load, different operating voltage, different life and / or different operating age of the reference actuator include. Method according to one of claims 1 to 4, wherein the measured value (Δy ') of the during the freewheeling phase ( 21 ) traveled by means of a Hall sensor ( 32 ), which is connected to one with a drive shaft ( 8th' ) of the reference actuator ( 1' ) coupled ring magnets ( 31 ) cooperates. Method according to Claim 5, in which the number of poles of the ring magnet ( 31 ) is selected such that it is an integer multiple of the number of current ripple of the motor current _magnitude (U _bemf ) per full motor _rotation . Method for determining the setting position (z) of a motorized actuating device ( 1 ) for a motor vehicle, - in which before and after a freewheeling phase ( 21 ) of a setting operation of the time points of current ripples (r _-3 , r _-2 , r _-1 , r ₁ , r ₂ ) of the motor current are detected, - in which the time interval (x ₁ ) between the last current ripple (r _-1 ) before the freewheeling phase ( 21 ) and the first current ripple (r ₁ ) after the freewheeling phase ( 21 ) and at least one time interval (x ₂ , x ₃ , x ₄ ) between two of the freewheeling phase ( 21 ) preceding and / or two of the freewheeling phase ( 21 ) subsequent current ripples (r _-3 , r _-2 , r _-1 , r ₁ , r ₂ ) are determined as characteristic variables of a predetermined interpolation function (F), and - in which by means of the interpolation function (F) as a function of these characteristic variables as interpolation result ( Δy) is a measure of the within the freewheeling phase ( 21 ), wherein the interpolation function (F) in addition to the characteristic variables by parameters (a, b, c, d, e, f, g) is determined, which were previously determined according to the method of one of claims 1 to 5. Adjusting device ( 1 ) for a motor vehicle with an electric servomotor ( 3 ) and with a control unit ( 10 ) for controlling the servomotor ( 3 ), which is set up to carry out the method according to claim 7.

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