WO2020120541A1

WO2020120541A1 - Assembly for a vehicle

Info

Publication number: WO2020120541A1
Application number: PCT/EP2019/084580
Authority: WO
Inventors: Daniel Stahl; Berthold Sieg
Original assignee: Huf Hülsbeck & Fürst Gmbh & Co. Kg
Priority date: 2018-12-12
Filing date: 2019-12-11
Publication date: 2020-06-18
Also published as: EP3895317A1; CN113169737A; DE102019133896A1; WO2020120541A4

Abstract

The invention relates to an assembly (10) for a vehicle (1) for detecting an activation action for the activation of a function at the vehicle (1), in particular in a front, side and/or rear region (1.7, 1.4, 1.2) of the vehicle (1) for the activation of the opening and/or unlocking of a hinged closure element (1.3, 1.6) on the vehicle (1), comprising: at least one sensor element (20) for sensing a change, in particular an approach of an activating means (3), in the surroundings of the sensor element (20); a sensor monitoring assembly (170), which is electrically connected to the sensor element (20) in order to provide a sensor signal specific to a parameter of the sensor element (20), the parameter being specific to the sensed change in the surroundings and to a variable load portion; a storage assembly (250), the storage assembly (250) being electrically connected to the sensor monitoring assembly (170) in order to carry out a repeated determination of the parameter of the sensor element (20) by means of the sensor signal (20); a compensation assembly (230) for adjusting the sensor signal in order to compensate the load portion; a connecting assembly (220) for dynamically electrically connecting the storage assembly (250) to the adjusted sensor signal in the event of the repeated determination.

Description

Arrangement for a vehicle

Description

The present invention relates to an arrangement for a vehicle. The invention further relates to a system and a method.

It is known from the prior art that a variable capacitance can be provided by means of a sensor element, such as a sensor electrode, which is specific for changes in the surroundings of the sensor element. This enables changes in the environment to be detected capacitively. In vehicles, such a capacitive detection can be used to detect approaches and / or gestures and thus to activate functions on the vehicle. The capacitive detection is often based on the fact that the sensor element is evaluated by means of a charge transfer. The shifting of electrical charges can, however, cause disruptive emissions (interference effects of the sensor element on the environment). In addition, disturbing influences from the environment (immissions on the sensor) can impair the detection.

In addition, other interferences on the detection are known, e.g. B. disruptive capacitive effects (parasitic capacitances, capacitive loads z. B. the vehicle body, or the like). It is therefore an object of the present invention to at least partially remedy the disadvantages described above. In particular, it is an object of the present invention to provide an improved capacitive detection.

The above object is achieved by an arrangement with the features of the independent device claim, a system with the features of the independent system claim and by a method with the features of the independent method claim. Further features and details of the invention emerge from the respective subclaims, the description and the drawings. Features and details that are described in connection with the arrangement according to the invention apply, of course, also in connection with the system according to the invention and the method according to the invention, and in each case vice versa, so that with respect to the disclosure of the individual aspects of the invention, reference is or can always be made to one another .

The object is achieved in particular by an arrangement for a vehicle for the detection of an activation action in order to activate a function on the vehicle, in particular for the detection of an activation action in a front, side and / or rear area of the vehicle for the activation of an opening and / or Unlocking a flap (each as the function) on the vehicle.

An arrangement according to the invention can have at least the following components, which are connected in particular to a circuit board of the arrangement:

at least one (in particular electrically conductive) sensor element for detecting a change, in particular an approach by an activation means, in an environment of the sensor element,

a (in particular electronic) sensor control arrangement which is electrically connected to the sensor element in order to provide a sensor signal which is specific for a parameter of the sensor element, the parameter preferably being specific for the detected change in the environment and for a variable load component,

a (in particular electronic) memory arrangement, the memory arrangement being electrically connected to the sensor control arrangement in order to be repeated To determine the parameter of the sensor element using the sensor signal,

a compensation arrangement for the (electrical) adaptation of the sensor signal, preferably to compensate for the load component, and in particular to provide compensation thereby,

a connection arrangement in order to electrically connect the memory arrangement to the adapted sensor signal during repeated determination (in particular dynamically and / or via the interconnection).

This has the advantage that the load component can be reliably compensated for during the repeated determination. In particular, compensation can also be carried out in stages by the compensation arrangement, so that a plurality of compensation stages are provided, in which different (predetermined) portions of the maximum permissible capacitive load are dissipated by the sensor signal. Each level can have a fixed proportion, with the proportions of different levels differing from one another. E.g. a first stage has a share of 10%, a second stage has a share of 20%, and a third stage has a share of 30%, this share always being removed (during the determination) from the sensor signal. Accordingly, the adaptation of the sensor signal and thus in particular of the charge transfers to the memory arrangement caused thereby can be understood as a derivative of the portion (of the sensor signal or the charge transferred thereby) according to a compensation specification. In other words, the sensor signal is reduced by this proportion with regard to a signal strength (e.g. current strength or voltage amplitude). It can be provided that the compensation arrangement is signal-connected to a control device, which also carries out the evaluation of the memory arrangement. Thus, the level and thus the proportion is known during the evaluation. E.g. a quantity of charge in the memory arrangement is evaluated during the evaluation, the quantity of charge being influenced by the sensor signal. The sensor signal can e.g. B. Initiate charge transfers to the storage arrangement so that the amount of charge transferred to the storage arrangement is proportional to the signal strength of the sensor signal. For this purpose, the sensor signal is designed as an electrical current and / or voltage signal. On the other hand, the amount of charge transferred can be reduced by the predetermined amount for each charge transfer, depending on the activated stage of the compensation arrangement. This enables a defined and adaptable attenuation of the sensor signal by the Compensation arrangement, which can be taken into account accordingly in the evaluation. Due to the compensation, the storage arrangement can also only have a smaller storage capacity, so that the costs for the storage arrangement can be reduced.

The “dynamic” connection refers in particular to the fact that the connection can be made adaptable and / or repeated and / or synchronized during the determination. For example, it is possible to use a control signal with a specific characteristic (such as a frequency and / or signal shape) to control the sensor element. The dynamic connection of the sensor signal, that is to say in particular the connection of the memory arrangement to a transmission path of the sensor signal, can then take place synchronized with the control signal and / or adapted to this characteristic. The connection arrangement can bring about a rectification of the sensor signal through the dynamic, in particular synchronized and / or controlled, connection, and thus can be designed as a rectifier arrangement.

It is also advantageous if the vehicle is designed as a motor vehicle, in particular as a hybrid vehicle or as an electric vehicle, preferably with a high-voltage electrical system and / or an electric motor. It may also be possible for the vehicle to be designed as a fuel cell vehicle and / or passenger vehicle and / or semi-autonomous or autonomous vehicle. Advantageously, the vehicle has a security system, which, for. B. enables communication by communication with an identification transmitter (ID transmitter). Depending on the communication and / or the authentication, at least one function of the vehicle can be activated. If the authentication of the ID transmitter is necessary for this, the function can be a safety-relevant function, such as unlocking the vehicle and / or enabling an engine start. The security system can thus also be designed as a passive access system which initiates the authentication and / or the activation of the function upon detection of the approach of the ID transmitter to the vehicle without active manual actuation of the ID transmitter. For this purpose, for example, a wake-up signal is repeatedly sent out by the security system, which can be received by the ID transmitter when approaching, and then triggers the authentication. The function can also activate vehicle lighting and / or actuate (open and / or close) a flap (e.g. front or rear or Side flap or door). E.g. the vehicle lighting is automatically activated when the approach is detected and / or the flap is actuated when a gesture of a user is detected.

It is also conceivable that - for the activation of the function on the vehicle - an activation action is detected by an arrangement according to the invention. In particular, this can be an activation action outside the vehicle (which therefore does not take place in the vehicle interior). In other words, the environment of the sensor element in which the change is detected can be outside the vehicle. If the activation action is successfully detected by the arrangement according to the invention, the function can be triggered and / or the authentication initiated by the arrangement (in particular by a control device). In the activation act, it can be e.g. B. the approach and / or the gesture, which is carried out by means of the activating agent. The activation means or the activation action can advantageously also be detected if the activation means is a non-electronic object (and therefore also not an ID transmitter). Instead, the activating agent can be designed as a non-electrical and / or non-metallic and / or biological substance, such as. B. a body part of a user. The use of a capacitive detection for the detection of the activation action is therefore particularly advantageous, since this does not require any special precautions on the activation agent.

An arrangement according to the invention is advantageously designed as an electronic circuit (circuit arrangement) and has electronic components which are at least partially arranged on a printed circuit board and can be connected to one another via electrical conductor tracks. At least one of these components can also be designed as an integrated circuit (such as a control device in the form of a microcontroller). Some of the components can also be designed as SMD (surface-mounted device) components. The sensor element can be electrically conductive, for. B. may be formed as a conductor track or as a flat electrode on the circuit board, or also connected to the circuit board via a supply line (such as an electrical line). In the latter case, the sensor element is designed, for example, as part of a cable (such as a coaxial cable), as a flat electrode or as an elongated conductor. The sensor element can also be understood as a capacitive antenna because of the sensor element a variable sensor capacity is provided. Furthermore, the variable sensor capacitance can optionally also be provided by a plurality of sensor elements which are operated simultaneously or alternately. The circuit board and / or the sensor element is, for. B. integrated in a door handle or in a bumper. The sensor element can be arranged in such a way that the arrangement of the sensor element defines a detection area for the activation action.

In an arrangement according to the invention, it is possible for the sensor element to be designed as a sensor electrode in order to provide the parameter specific for the detection as a variable capacitance (also referred to as sensor capacitance), the change in the capacitance being specific for the change in the surroundings of the sensor element can. At least one shield element can in turn serve to shield a change in a region to be shielded from the sensor element, so that this change does not lead to a significant change in the capacitance.

In addition, it can be provided that a control signal is used for the control of the sensor element and a sensor signal is used for the evaluation of the sensor element. The sensor signal can be dependent on the control signal. A charge transfer in the sensor element can also depend on the control signal, since, for. B. an electrical voltage on the sensor element follows the control signal (or corresponds to the electrical voltage of the control signal).

It can be provided that the sensor signal and / or the charge transfers in the sensor element essentially

- Has the same frequency (working frequency) as the control signal, and / or

has the same signal shape as the control signal, preferably a sinusoidal shape and / or a periodic oscillating shape, and / or

has a frequency in an operating frequency range, the frequency (operating frequency) of the control signal also being in this operating frequency range,

is carried out in phase or polarity,

has the same direct voltage and / or direct current offset (or DC offset), - Has a reduced frequency spectrum, which is adapted by a filter arrangement and / or an evaluation filter arrangement.

Furthermore, it is conceivable that the sensor signal is present as alternating current (or alternating voltage) at least after (or by) filtering an evaluation filter arrangement. Filtering by the evaluation filter arrangement can also be implemented as bandpass filtering. On the other hand, the control signal can be filtered, in particular by the filter arrangement, as low-pass filtering in order to maintain a DC voltage component in the control signal.

Furthermore, it may be possible that the evaluation filter arrangement is designed to carry out a transconductance conversion of the sensor signal as an alternative or in addition to the bandpass filtering. In the context of the invention, a transconductance conversion is understood in particular to mean that an electrical voltage is converted into an electrical current which is proportional and preferably the same. Functionally, this can correspond to the function of a transconductance amplifier, possibly with an amplification factor (proportionality factor) of at most 1. However, in contrast to the transconductance amplifier, the evaluation filter arrangement cannot have an operational amplifier, but rather the transconductance conversion by means of the complex resistor and in particular through the connection in series with the virtual one Achieve zero.

The frequency of the sensor signal (as a periodic signal) can be dependent on an operating frequency, ie in particular the frequency of the control signal at the output of a filter arrangement of the control arrangement. A single working frequency can advantageously be used for the entire arrangement according to the invention both for the control and for the evaluation, in particular capacitive sensor evaluation, of the sensor element in order to carry out the control and evaluation of the sensor element with a predetermined working frequency range. For this purpose, filtering is used in particular in the electrical control (by the filter arrangement) and in the evaluation (by an evaluation filter arrangement), the filtering being adapted to the working frequency (e.g. forming a low and / or bandpass to pass the working frequency range ). This enables an optimal evaluation regarding EMC (electromagnetic compatibility) conditions (with emissions) and disturbing influences (with immissions). Can also by generating the control signal and / or the adaptation of the signal shape and / or frequency of the control signal, an emission of the sensor element and a susceptibility to interference for immissions can be set very precisely. However, in order to be able to use these set properties also in the sensor evaluation, the sensor signal can also be adapted in accordance with the control signal. For this purpose, the sensor signal can be specific for the charge transfers and nevertheless has the set properties. For this, z. B. uses a (the) sensor control arrangement, which outputs the control signal as a function of the charge transfers (and thus the sensor capacitance of the sensor element) as the sensor signal. This is e.g. B. possible by using an operational amplifier in the sensor control arrangement, which has negative feedback by means of a capacitor.

The memory arrangement can preferably be designed as an electronic integrator, in particular in order to accumulate received charges. Preferably, several charge transfers after several charges and discharges of the sensor element can be used to charge the memory arrangement.

A further advantage within the scope of the invention can be achieved if a control arrangement is electrically connected to the sensor element via the sensor control arrangement, in order to provide electrical control of the sensor element via the sensor control arrangement, and in order to carry out charge transfers between the sensor control arrangement and the storage arrangement as one , in particular to provide a sinusoidal and / or oscillating, periodic signal in order to initiate the charge transfers alternately in different current directions, the connection arrangement being designed to electrically connect the memory arrangement to the adapted sensor signal only during the charge transfers in one of the current directions, or in the case of the Charge transfers in both of the current directions via a full-wave rectification to electrically connect the memory arrangement to the adapted sensor signal. In this way, the dynamic connection can be made in order to allow only charge transfers in the direction of the storage arrangement. This makes it possible to charge the memory arrangement as a function of a signal strength of the sensor signal, in order to evaluate the parameter of the sensor element on the basis of the state of charge of the memory arrangement. In order to use the sensor signal to charge the memory arrangement, an evaluation filter arrangement for filtering and / or Transconductance conversion of the sinusoidal signal between the sensor control arrangement and the memory arrangement.

According to an advantageous development of the invention, it can be provided that an evaluation filter arrangement is provided which is electrically connected to the sensor control arrangement in order to filter the output of the provided sensor signal to the memory arrangement, and preferably in dependence on one generated for charging and / or discharging the sensor element electrical voltage signal (in particular control signal) of a signal generator arrangement to filter the sensor signal and / or to provide the sensor signal as an electrical current signal for carrying out charge transfers to the memory arrangement as a function of the parameter of the sensor element. The current signal can essentially have the signal shape, preferably a sinusoidal shape, corresponding to the voltage signal. The connection arrangement is preferably switched in a synchronized manner depending on the signal form, so that only the charge transfers in a given current direction are passed on unchanged to the storage arrangement and / or the charge transfers in the other of the current directions are rectified synchronously. The sensor signal can be at the output of the sensor control arrangement z. B. in the form of a voltage signal, which is converted by the evaluation filter arrangement (z. B. by means of a transconductance conversion and in particular due to the serial connection with the memory arrangement) in a current signal. This enables the parameter to be evaluated on the basis of the charge transfers to the storage arrangement. The filtering can also be dependent on the control signal since, according to a bandpass filtering, it only allows the operating frequency of the control signal (or an operating frequency range with the operating frequency) to pass.

In an arrangement according to the invention it can be provided that only a certain half-wave of the sensor signal or current signal is forwarded to the memory arrangement and the other half-wave is blocked, so that the connection arrangement forms a rectifier arrangement. In other words, the compensation arrangement is not connected directly and permanently to the input of the memory arrangement. Rather, it is provided that the compensation arrangement (possibly via a virtual zero point) is repeatedly connected to the storage arrangement and then separated from it again. Accordingly, it can be a special feature of the invention that the Compensation arrangement is only connected to the storage arrangement if a specific (like the negative or positive) half-wave is also passed through the connection arrangement, in particular a rectifier arrangement. Otherwise, the compensation arrangement is electronically separated from the storage arrangement and is therefore not effective for the storage arrangement or the charge stored therein. In other words, the compensation on the memory arrangement takes place only when the connection arrangement (rectifier arrangement) is switched. The storage arrangement thus “sees” either the virtual zero point or a ground potential, so that no currents flow back from the storage arrangement to the storage element. The integration and thus the evaluation of the parameter can thus be more robust and / or less prone to failure and / or more reliable.

It can be provided in the context of the invention that the connection arrangement is designed as a rectifier arrangement in order to pass on charge transfers by the adapted sensor signal in the direction of the storage arrangement by repeated switching. In this case, in particular, the compensation arrangement can be connected to the memory arrangement only during this forwarding, and preferably otherwise the memory arrangement and / or the compensation arrangement and / or the evaluation filter arrangement can be connected to a ground potential. The switching can be effected by repeatedly changing the switching state of the switching arrangement between a closed (low resistance) and an open switching state (high resistance, blocking resistance). In this way it can be ensured that the storage arrangement is only charged and not discharged by the sensor signal. In other words, charge accumulation is effected for successive charge transfers, in which only charge transfers in one direction to the storage arrangement are permitted. The connection to ground potential can thereby relieve the evaluation filter arrangement, so that the filtering of the sensor signal can be carried out more reliably.

In addition, it is conceivable within the scope of the invention that the connection arrangement is designed to connect the compensation arrangement and / or an evaluation filter arrangement to the storage arrangement via a virtual zero point, so that, depending on the switching state of the connection arrangement, the compensation arrangement and / or an evaluation filter arrangement preferably have either a ground potential or the virtual zero point connected is. Since a connection to a ground potential can always be provided in this way, at least approximately, which is provided either by the “real” ground potential or the virtual zero point, relief of the evaluation filter arrangement can be made possible, so that the filtering of the sensor signal can be carried out more reliably.

Advantageously, it can be provided in the context of the invention that the compensation arrangement is designed to always derive a defined portion of the transferred charge in the case of repeated charge transfers by the adapted sensor signal to the storage arrangement, the compensation arrangement preferably being connected to a control device in order to reduce the defined portion in To be determined depending on the load share according to a compensation specification. To carry out this determination, e.g. B. to select the compensation specification, the control device can evaluate the determined parameter and, depending on this, set the compensation specification. In this way, the proportion depending on the (changeable) load proportion can be flexibly determined in order to reliably enable the evaluation even when the load proportion changes.

Furthermore, it can be provided within the scope of the invention that a control device is connected to the memory arrangement and to the compensation arrangement in order to determine a compensation specification for the compensation arrangement as a function of the currently determined parameter. The currently determined parameter is e.g. B. determined by means of a measurement such as an analog-digital conversion or the like by the control device in that a voltage across the memory arrangement is detected. In this way, an optimal portion can always be derived. The compensation specification is, for example, a specification of the level at which the portion of the sensor signal is derived. The compensation specification can e.g. B. be a control signal of the control device for the compensation arrangement.

Furthermore, it can be provided that the compensation arrangement has different compensation stages in order to activate them in a controlled manner by a compensation specification and / or by a control device, and in order to derive different defined fixed portions of the sensor signal, in particular a charge transmitted by the sensor signal, in the different compensation stages , whereby the adapted sensor signal is provided. In particular, if one or more limit values are exceeded by the amplitude of the voltage on the storage arrangement (or another parameter specific for the amount of charge in the storage arrangement), a switch is made to another compensation stage, in which a higher proportion of the transmitted charge is derived. If another limit value is exceeded again, you can switch again. In this way, a multi-stage load component compensation can be provided.

According to a further possibility, it can be provided that the compensation arrangement has at least three or at least four or at least five or at least 10 or at least 16 (in particular according to 4-bit) different compensation stages, in order to have different defined fixed portions of the transferred charge for different load components during the charge transfers to derive. The compensation levels can e.g. B. in the form of a circuit adaptation in the compensation arrangement (z. B. by the interconnection and / or connection of different resistors). This ensures reliable compensation.

It is also conceivable within the scope of the invention that the sensor element is designed as a sensor electrode in order to provide the parameter specific for the detection as a variable capacitance. The change in capacity can be specific to the change in the environment. It is possible for the sensor control arrangement to be electrically connected to the sensor element and the memory arrangement in order to provide the sensor signal for repeated determination and to output it to the memory arrangement, in particular in the form of an integrator, as a function of a charge transfer between the sensor element and the sensor control arrangement. This is achieved, for example, by generating the sensor signal with a signal strength which is dependent on the charge transfer. In this way, the sensor signal is generated by amplifying the control signal or a voltage on the sensor element, the amplification being dependent on the capacitance. An electrical charge that is transmitted and in particular accumulated by the sensor signal in the memory arrangement is correspondingly specific for the change in capacitance. This has the advantage that the change in capacity can be evaluated in a simple manner using the memory arrangement. It is also conceivable that a control device is connected to the memory arrangement in order to evaluate an electrical charge stored by the memory arrangement in order to determine the parameter specific for the detection, preferably by an analog-digital conversion of a voltage in the memory arrangement, preferably by means of the Evaluation to define a compensation specification. In addition to or as an alternative to analog-to-digital conversion, the evaluation can also use other measurement methods to obtain the most accurate measurement possible for the voltage.

It is also advantageous if a shield element is provided to shield the sensor element in order to reduce the load component, an electronic shield control arrangement being preferably provided for this purpose in order to set an electrical potential on the shield element on the basis of the electrical potential of the sensor element. The shield element can optionally be connected directly to the potential of the sensor element by means of the shield control arrangement. In this way, the potential of the shield element follows the potential of the sensor element. The shield control arrangement can have a voltage follower or the like for correspondingly guiding the potential of the shield element.

Provision can preferably be made for the arrangement as a capacitive sensor arrangement to be at least partially fastened in a bumper of the vehicle in order to monitor the rear area of the vehicle and to function as the function on the vehicle of the tailgate (and / or front flap and / or sliding door on one side) ) to open the vehicle, in particular to output an opening signal and / or

Initiate authentication check, the position of the arrangement on the vehicle correlating with the load share. For example, the arrangement in the vicinity of structures of the vehicle can increase the load share. In the same way, a side or front area can also be used instead of the rear area in order to enable convenient activation of the function.

It can preferably be provided within the scope of the invention that the sensor control arrangement for the electrical signal transmission is connected to the sensor element in order to repeatedly transmit electrical charges from and / or into the sensor element by the signal transmission, and to use this Charge transfers to provide the sensor signal. In particular, the amount of charge in the sensor element depends on the parameter (for example the sensor capacity), so that the charge transfers provide a reliable possibility for capacitive detection and evaluation.

It can optionally be provided that the sensor control arrangement for the electrical signal transmission (in particular charge transfers) is connected to the sensor element via a first connection, to which an electrical input signal (in particular in the form of an electrical voltage) is present depending on the signal transmission. Furthermore, the sensor control arrangement can be electrically connected to the memory arrangement via a second connection in order to provide the sensor signal. In other words, the sensor signal can be present at the second connection. The sensor control arrangement can have an amplifier arrangement in order to output the sensor signal in the form of the input signal amplified as a function of the parameter of the sensor element at the second connection. Specifically, the input signal can be amplified as a function of and, in particular, proportional to the variable sensor capacitance, and thus represent the sensor signal specific for the sensor capacitance.

It can advantageously be provided within the scope of the invention that a control device, in particular at least one microcontroller, is electrically connected to a signal generator arrangement in order to provide the sensor signal as a, in particular sinusoidal, oscillating and / or periodic signal, and in particular is electrically connected to the memory arrangement to evaluate the amount of the charge stored in the storage arrangement and / or accumulate after several charge transfers after a charge transfer by the sensor signal to the storage arrangement, and to carry out the detection based on the evaluation, preferably to output an activation signal to activate the function on the vehicle when the Amount of charge exceeds a limit. The signal generator arrangement can e.g. B. influence the signal shape and / or frequency of the sensor signal in that the signal generator arrangement outputs a control signal which is present at a connection of the sensor control arrangement. The control signal can have the signal shape and / or frequency which is used for the control of the sensor element and for the sensor signal. For this is the Connection of the sensor control arrangement, to which the sensor signal is present, e.g. B. connected via an operational amplifier to the connection of the sensor control arrangement to which the control signal is present.

The invention also relates to a system comprising:

an arrangement according to the invention,

a control device for outputting an activation signal in the event of detection of the activation action (by the arrangement according to the invention, the control device being connected to the arrangement according to the invention for this purpose),

a control unit, which is connected to the control device (in particular in terms of signal technology) in order to carry out the function on the vehicle when the activation signal is received.

The system according to the invention thus brings with it the same advantages as have been described in detail with reference to an arrangement according to the invention.

The invention also relates to a method for a vehicle for detecting an activation action for activating a function on the vehicle, in particular in a front, side and / or rear area of the vehicle for activating an opening and / or unlocking of a flap on the vehicle.

It is provided here that the following steps are carried out, preferably in succession in the order specified or in any order, individual steps also being able to be carried out repeatedly:

Performing a provision of a sensor signal that is specific to a parameter of the sensor element, the parameter being specific for the detected change in the environment and for a variable load component,

Adjust the sensor signal to compensate for the load component

Carrying out a repeated determination of the parameter of the sensor element on the basis of the sensor signal by means of a memory arrangement in order to carry out the detection of the activation action,

wherein performing the repeated determination comprises the following step:

Initiate an electrical connection of the memory arrangement with the adapted sensor signal dynamically during the repeated determination. The method according to the invention thus brings with it the same advantages as have been described in detail with reference to an arrangement according to the invention. In addition, the method can be suitable for operating an arrangement according to the invention.

It can further be provided in a method according to the invention that, for an initial precharging of the memory arrangement in particular, the compensation arrangement is connected to an electrical potential as a precharge potential, in particular a ground potential which differs from an electrical potential at the memory arrangement in order to charge a capacitor of the memory arrangement , wherein preferably to adjust the charge transfers, the compensation arrangement is connected to an electrical potential that differs from the precharge potential. This enables a particularly cost-saving precharge solution. The subpoena is z. B. performed to provide an initial state, which is necessary for the evaluation.

Further advantages, features and details of the invention result from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination. Show it:

FIG. 1 shows a schematic view of a rear area of a vehicle with an arrangement and a system according to the invention,

FIG. 2 shows a schematic side view of a vehicle with an arrangement according to the invention and a system according to the invention,

Figure 3 is a schematic diagram of parts of an inventive

Arrangement,

Figure 4 is a schematic diagram of parts of an inventive

Arrangement, Figure 5 is a schematic representation of parts of an inventive

Arrangement or a system according to the invention,

Figure 6 is a schematic representation of parts of an inventive

Arrangement or a system according to the invention, and

Figure 7 is a schematic representation for the visualization of an inventive

Systems.

In the following figures, the same reference numerals are used for the same technical features of different exemplary embodiments.

FIG. 1 shows a view of a rear area 1.2 of a vehicle 1 with a system according to the invention. An arrangement 10 according to the invention can be integrated in a bumper 1.1 of the vehicle 1 in order to detect an activation action by an activation means 3 (such as a leg 3) of a user 2 in the area of the bumper 1.1. For this purpose, the arrangement 10 has a sensor element 20, which can be designed, for example, as an elongated and / or cable-shaped electrode 20 or as a flat electrode 20 (i.e. flat electrode) or as a capacitive antenna. It is also possible that a cable, such as a coaxial cable, is used to form the sensor element 20. Detection of the activation action can lead to a tailgate 1.3 of the vehicle 1 being opened. For this purpose, the arrangement 10 can have a signal connection to a control unit 8 of the vehicle 1 in order to output an activation signal to the control unit 8 via the signal connection, which initiates the opening of the tailgate 1.3. Successful authentication with an identification transmitter 5 may be required for the opening. In the same way, a flap, in particular door 1.6, in the front area 1.7 and / or in the side area 1.4 of the vehicle can also be activated by an arrangement 10 according to the invention, whereby the arrangement 10 then z. B. is integrated in the door handle 1.5 or also in the bumper 1.1 or on a side sill.

In Figure 2, a vehicle 1 is shown schematically in a side view. The side area 1.4 and / or the front area 1.7 of the vehicle 1 can have an arrangement 10 according to the invention as an alternative or in addition to the rear area 1.2. E.g. is this Sensor element 20 integrated in the side area 1.4 in a door handle 1.5 of the vehicle in order to detect the activation action in the area of the door handle 1.5. For example, an approach to the sensor element 20 can be detected by the arrangement 10 in the side region 1.4 as an activation action. This activation action can include reaching an activation means 3 (such as a hand) into a door handle recess of the door handle 1.5. The arrangement of the sensor element 20 in the front region 1.7 can in turn be provided in the bumper 1.1 in order to, for. B. when detecting the activation action in the front area 1.7 to open a front flap. Another possible function, which can be activated by an activation action, can be the opening of sliding doors 1.6 of vehicle 1, e.g. B. by approaching a side sill of the vehicle.

In principle, the activation action can include an approach to the sensor element 20 or a gesture or the like. In particular for the detection of gestures, in addition to a single sensor element 20, at least one further sensor element 20 'can be provided and arranged adjacent to the sensor element 20. This makes it possible to recognize a movement of the activation means through the different detection of the sensor elements 20, 20 '. A shield element 160 for shielding can also be arranged adjacent to the sensor element 20 and / or further sensor element 20 ′. In Figure 1, this arrangement is shown as an example in the bumper 1.1.

FIG. 3 shows an arrangement 10 according to the invention for a vehicle 1 which is used to detect an activation action for the activation of a function on the vehicle 1, in particular as described in accordance with FIGS. 1 and 2 for detecting the activation action in a front, side and / or Rear area 1.7, 1.4, 1.2 of vehicle 1 for activating an opening and / or unlocking of a flap 1.3, 1.6, in particular door 1.6, on vehicle 1.

The arrangement 10 according to the invention can have at least one sensor element 20 for detecting a change in an environment of the sensor element 20. This change is caused, for example, by the activation action, for example an approach by an activation means 3. The sensor element 20 can be an electrical conductor, such as an electrically conductive surface (in particular when the arrangement 10 is installed in the door handle 1.5) or an elongated and if necessary, planar electrode (in particular when mounting in the bumper 1.1). The sensitivity of the sensor element 20 to changes in the environment and thus to the activation action can be explained in a simplified manner, for example, as follows. Compared to the environment and / or a ground potential 21, the sensor element 20 can form a capacitance (hereinafter also referred to as sensor capacitance CS). By generating an electrical potential (by means of an electrical control described below) on the sensor element 20, an electrical field can arise in the environment. The sensor capacity CS is influenced by the change in the environment and is therefore variable. In other words, the change in the sensor capacitance CS correlates with the change in the environment, ie the presence of an activation action. The variable capacitance CS can be evaluated in particular by evaluating the amount of charge stored in the sensor element 20 and can draw conclusions about the change in the environment, and thus serve to detect the activation action. Thus, carrying out charge transfers from and to the sensor element 20 is particularly suitable for providing a sensor signal on the basis of the charge transfers (such as the amount of charge transferred and / or the current intensity and / or voltage that can be detected), which can be evaluated for the determination of the variable capacitance CS .

A control arrangement 100 (in the sense of a control arrangement 100) can be used to carry out the electrical control. The control arrangement 100 can be electrically connected to the sensor element 20 for the electrical control of the sensor element 20 via a control path KP in order to provide (ie enable) the detection. Due to the electrical control z. B. a (positively driven) charging and discharging of the sensor element 20 can be initiated via charge transfers in order to allow capacitive detection based on this activation of the sensor element 20. The electrical connection can, for. B. can be realized by means of an electrical connection via conductor tracks of a circuit board. The arrangement 10 according to the invention can be arranged at least in part on this printed circuit board as an electrical circuit. The sensor element 20 and / or the further sensor element 20 'and / or the at least one shield element 160 can be electrically connected to the control arrangement 100 of the arrangement 10 via conductor tracks via an electrical connection of the printed circuit board, or can itself be designed as a conductor track. The detection is provided, for example, in that an electrical potential through the control arrangement 100 on the sensor element 20 is generated to charge the sensor element 20, and thus as previously described, for. B. allows the evaluation of the variable capacity CS. It can also be a changing potential, so that an electrical voltage on the sensor element 20 z. B. is generated as a periodic and / or sinusoidal voltage. To evaluate the sensor element 20, an evaluation arrangement 200 is provided, which carries out a repeated determination of at least one parameter of the sensor element 20 which is specific for the detection, in order to carry out the detection of the activation action. In the example specifically described, the variable capacitance CS is regarded as this parameter.

In addition, it is possible that at least one shield element 160 is provided, which is arranged adjacent to the sensor element 20 to shield the sensor element 20 (and thus in the effective range). In order to enable shielding by the shield element 160, a shield control arrangement 150 with a connection 150.A is provided for the shield element 160. The shield control arrangement 150 can be electrically connected to the control path KP and thus also to the shield element 160 via a shield control input 150.B for providing the (previously described) electrical control of the control arrangement 100 for the shield element 160. In other words, the shield control arrangement 150 can provide the same electrical control for the shield element 160 that is also used for the sensor element 20. For this purpose, an electrical output voltage at the output 150.A of the shield control arrangement 150, which is electrically connected to the shield element 160, follows an input voltage at the input 150.B of the shield control arrangement 150, which in turn is electrically connected to the control path KP and thus also to the sensor element 20 is connected. In this way, the same control signal can be used for the sensor element 20 and for the shield element 160 in order to set the potential on the sensor element 20 and on the shield element 160 in the same way by means of the control signal.

A connection point on the control path KP can be used to connect the shield control arrangement 150 to the control path KP. Various positions on the control path KP come into question, e.g. B. directly on the current path to the sensor element 20 or between a filter arrangement 140 and a sensor control arrangement 170. In FIG. 3, two possible ones are exemplary and not conclusively with a broken line Connection points of the shield control input 150.B shown with the shield control arrangement 150. When using the connection point at the connection 170.C of the sensor control arrangement 170, the control signal which is output by the filter arrangement 140 can be used to set the potential on the shield element 160. When using the connection point directly on the current path to the sensor element 20, the (essentially) the same potential that is present on the sensor element 20 is used to set the potential on the shield element 160.

In order to adapt the electrical control in a particularly reliable manner and in particular not to place excessive loads on the components at the connection point (such as the sensor element 20 or the control arrangement 100), the shield control arrangement 150 can have an operational amplifier 150.1 for electrically guiding the shield element 160. This can be used to connect the control path KP to the shield element 160 and thus to generate the output voltage (also referred to as shield voltage) on the shield element 160 equal to the input voltage on the control path KP. The input voltage corresponds to a control voltage which is specific and / or proportional to the electrical voltage at sensor element 20. The shield control arrangement 150 can preferably form a voltage follower so that an electrical potential on the shield element 160 follows the electrical potential on the control path KP and in particular on the sensor element 20. Correspondingly, a direct negative feedback of the operational amplifier 150.1 can be provided in order to obtain an amplification factor of 1. The shield control input 150.B can be (directly) electrically connected to the positive (non-inverting, high-resistance) input of the operational amplifier 150.1, so that the input resistance of the shield control input 150.B is very large in order to only slightly load the voltage at the shield control input 150.B. . The shield element connection 150.A, on the other hand, can be (directly) electrically connected to the output of the operational amplifier 150.1 and, due to the negative feedback, possibly also to the inverting input of the operational amplifier 150.1, in order to provide an output which is low-impedance compared to the input resistance.

It can also be seen from FIG. 3 that the control arrangement 100 has a signal generator arrangement 130 which is electrically connected to the sensor element 20 for the electrical control of the sensor element 20 in order to repeatedly generate an electrical signal for charging the sensor element 20. This electrical Signal, also referred to below as a control signal, can serve for the described electrical control, and thus for the sensor element 20, possibly also for the further sensor element 20 ', and in particular also for the at least one shield element 160 for setting the electrical potential and / or electrical charging and discharging can be provided. This provision is made, for. B. by the transmission of the electrical signal via at least part of the control path KP to a sensor control arrangement 170 and / or to a shield control arrangement 150. The generation of the activation signal by the signal generator arrangement 130 thus has the effect that the activation signal (possibly previously changed, in particular filtered) is present at connection 170.C. The sensor control arrangement 170 and / or the shield control arrangement 150 can in turn be used to control the sensor element 20, the further sensor element 20 ′ and / or the shield element 160 on the basis of the control signal. For this purpose, a charge transfer (charging and / or discharging) is initiated on the sensor element 20 or the further sensor element 20 ′ and / or the shield element 160 (and thus also the creation of an electric field is initiated) on the basis of the control signal. The evaluation of the amount of the transferred charge can enable an evaluation of the variable sensor capacitance CS. The time course of this charge transfer can be influenced by the shaping of the electrical signal. For this purpose, the signal generator arrangement 130 z. B. a digital-to-analog converter 130.1, which can also be implemented as part of a control device 300 such as a microcontroller. The signal generator arrangement 130 can optionally also be completely part of the control device 300. It is also conceivable that the signal generator arrangement 130 is only partially integrated in the control device 300, and z. B. the digital-to-analog converter 130.1 is formed separately therefrom. A certain signal form of the control signal can thus be determined very reliably and precisely. This signal shape can optionally be further shaped and / or improved by subsequent filtering, so that the control signal subsequently has, for example, a sinusoidal shape according to an operating frequency. The control arrangement 100 can therefore have a filter arrangement 140, in particular an active filter 140 e.g. B. have a low pass filter. As shown, this can be connected downstream of the signal generator arrangement 130 in order to filter the control signal for the electrical control of the sensor element 20 via the control path KP to the sensor control arrangement 170, in particular by low-pass filtering. In this way, the control signal can be shaped with a specific operating frequency, so that preferably an emission of the sensor element 20 by the Filter arrangement 140 is adapted. In this way, EMC (electromagnetic compatibility) specifications can advantageously be implemented during the operation of the arrangement 10. In other words, the control arrangement 100 can have a filter arrangement 140, in particular an active filter 140, which connects the signal generator arrangement 130 to the control path KP in order to filter, in particular low-pass filtered, and / or shaped an electrical signal generated by the signal generator arrangement 130 on the control path KP to provide, and thereby to provide as a filtered electrical signal, preferably a sine signal. Active filtering is preferably made possible by an operational amplifier 140.1 and by filter elements 140.2 such as at least one capacitor and / or at least one resistor and / or at least one coil.

The electrical signal (control signal) on the control path KP and in particular on the connection 170.C can now optionally be output to the sensor element 20 via further components such as the sensor control arrangement 170 and via a switching element 180 (possibly via a connection 180.A). In order to interrupt the charge transfer thereby caused to the sensor element 20 and z. B. to charge at least one further sensor element 20 ', the switching element 180 can be opened in a clocked manner and then closed again. The sensor control arrangement 170 can have an amplifier and / or a voltage follower and / or a voltage multiplier in order to generate an electrical potential at the connection 170.C in the same way on the sensor element 20, preferably so that the electrical potential at the sensor element 20 corresponds to the electrical potential at the connection 170 .C follows. For this purpose, the sensor control arrangement 170 z. B. an operational amplifier 170.1 and / or at least one filter element 170.2, such as a capacitor 170.2. Another switching element 180 may e.g. B. in the path between the connection 170.A and the further sensor element 20 ', and z. B. can be switched alternately with the switching element 180.

The sensor control arrangement 170 can have the operational amplifier 170.1 as a transmission element 170.1, which is electrically connected to the signal generator arrangement 130 in order to initiate repeated charge transfers at the sensor element 20 on the basis of the control signal (at the connection 170.C). This enables at least partial charging and discharging of the sensor element 20, and thus an evaluation of the charge stored in the sensor element 20. For this purpose, for example Amount (number) of the transferred charges and / or a current during the charge transfers are evaluated. The amount of charge and / or current strength is then specific for sensor capacitance CS, in particular for the change in sensor capacitance CS. For this evaluation of the sensor element 20, the sensor control arrangement 170 can furthermore have the at least one filter element 170.2 as a reinforcing means 170.2, which is electrically connected to the evaluation arrangement 200 (and also to the sensor element 20) and thus provides the sensor signal on the basis of the charge transfers. The sensor signal is specific to the (e.g. proportional to) the sensor capacitance CS. Specifically, the sensor signal is e.g. B. specifically for the current strength of the electrical current and / or a voltage which is present at the connection 170.A, and thus specifically for the charge transfers or the sensor capacitance CS.

In order to enable conclusions to be drawn about the sensor capacitance CS on the basis of the sensor signal, the amplification means 170.2, as shown in FIG. 3, can be electrically connected to the sensor element 20 in order to provide charge transfers (ie an electrical current flow) between the sensor element 20 and the amplification means 170.2. Furthermore, the amplification means 170.2 can electrically connect an output of the transmission element 170.1 to an (in particular inverting) first input of the transmission element 170.1, so that the amplification means 170.2 forms a negative feedback for the transmission element 170.1. The negative feedback enables the charge transfers to be controlled by the control signal when the control signal is present at the other (in particular non-inverting) second input of the transmission element 170.1. If the first input is electrically connected directly to the connection 170.A, as is also shown in FIG. 3, the sensor control arrangement 170 thus provides a voltage follower for the sensor element 20, so that the voltage at the (in particular low-resistance) connection 170 .A follows the control signal at (in particular high-resistance) connection 170.C. This corresponds to the control of the charge transfers at connection 170.A by the control signal, and thus a (particularly low-resistance) sensor supply. By contrast, the sensor signal can be provided by means of the arrangement (amplifier arrangement) comprising the transmission element 170.1 and the amplification means 170.2, which can be an electronic amplifier. The transmission element 170.1 is preferably designed as an operational amplifier 170.1. The reinforcing means 170.2, on the other hand, has at least one or two filter elements 170.2, in which, however, a capacitor C (for example with respect to a resistor R) can dominate. The configuration of the arrangement comprising the transmission element 170.1 and the amplifying means 170.2 can thus also be regarded as an integrating circuit. The capacitor C makes it possible to provide an electronic amplifier through this arrangement, in which the sensor signal is generated in the form of an electrical voltage proportional to the sensor capacitance CS based on the charge transfers. In other words, the sensor control arrangement 170 has the arrangement of the transmission element 170.1 and the amplification means 170.2 in order to provide the sensor signal with an amplification. This means that the sensor signal is dependent on, and is preferably proportional to, a voltage U1 at a first connection 170.A of the sensor control arrangement 170 (or at the first input of the operational amplifier 170.1), amplified by an amplification factor. The amplification factor can be dependent on, and preferably be proportional to, a ratio of the sensor capacitance CS to the capacitance Cmess of the capacitor C. The voltage U1 (the output signal) at the terminal 170.A can in turn be avoided by using the voltage follower or a direct negative feedback Control signal in the form of a voltage U0 at connection 170.C essentially correspond. This results in the following relationship for the sensor signal, which can be present as voltage U2 at connection 170.B of sensor control arrangement 170:

U2 = U0 * (1 + CS / Cmess)

It can be seen that the sensor signal U2 is amplified as a function of the variable sensor capacitance CS and the capacitance Cmess, that is to say is generated as an amplified voltage U0. Consequently, the sensor signal can be used to determine the sensor capacitance CS. In order to enable the linearity shown between the sensor signal and the sensor capacitance CS, the resistance R of the amplification means 170.2 is chosen to be as large as possible compared to (1 / (2 * TT * fO * CSmax)), with fO being the working frequency, in particular the (middle ) Frequency of the control signal, and CSmax is the maximum value of the sensor capacitance CS. The capacitance Cmess can, if necessary, be selected to be identical to the maximum sensor capacitance. The setting of Cmess consequently also enables the setting of a dynamic range when evaluating the sensor element 20. In addition, the arrangement of the transmission element 170.1 and the amplifying means 170.2 in cooperation with the sensor capacitance CS provides a filter behavior (in particular bandpass behavior) which is adapted to the working frequency can.

The maximum variable sensor capacitance is, for example, the capacitance (the capacitance value) which the sensor capacitance CS can maximally assume during the activation action.

It is also conceivable that the amplification means 170.2 has at least one filter element 140.2 a capacitor C and / or a resistor R, the capacitor C (or the capacitance Cmess of the capacitor C) and / or the resistance R to a maximum variable sensor capacitance CS is adjusted. The capacitance Cmess of the capacitor C can preferably correspond to the maximum variable sensor capacitance. The capacitor C can be designed for negative feedback in the transmission element 170.1 (in particular operational amplifier 170.1) of the sensor control arrangement 170, and thus preferably form a feedback capacitor C. Via capacitor C, the output of transmission element 170.1 and in particular output 170.B, to which the sensor signal is present, can be fed back to an input of transmission element 170.1. In addition, this input can be connected directly to the connection 170.A, to which the sensor element 20 is connected (possibly via a switching element 180), and thus the output signal or an electrical voltage of the sensor element 20 is present. In this way, the output signal can be generated via a direct negative feedback corresponding to the control signal (follow this). In addition, the drive signal or the output signal can be amplified in this way depending on the charge transfers (initiated by the output signal) on the sensor element 20 (with an amplification factor that depends on the sensor capacity), and then outputted as the sensor signal amplified at the terminal 170.B.

For the evaluation of the parameter specific for the detection and in particular the variable sensor capacitance CS, the charge transfer from the sensor element 20 (or the further sensor element 20 ′) to the sensor control arrangement 170 is provided in accordance with the above statements in order to carry out this charge transfer using the Evaluate sensor signal by an evaluation arrangement 200. For repeated determination, a charge transfer from the sensor element 20 to the sensor control arrangement 170 is carried out repeatedly in order to charge a storage arrangement 250, preferably an integrator 250, of the evaluation arrangement 200 depending on the amount of the charge transferred in the process. In other words, the memory arrangement 250 is charged as a function of, and preferably in proportion to, the sensor signal. In this way, the electrical charge stored by the storage arrangement 250 can be specific for the change in the capacitance CS. For this purpose, the memory arrangement 250 can e.g. B. provide a storage capacity CL by means of a storage capacitor.

The control device 300 can be connected via a connection 250.A to the storage arrangement 250 of the evaluation arrangement 200 in order to evaluate the electrical charge stored by the storage arrangement 250 in order to determine the parameter specific for the detection. An evaluation signal that is specific to the parameter and / or the stored electrical charge is thus detected and evaluated. The evaluation signal can, for. B. be a voltage across a capacitor of the memory array 250.

It can also be seen in FIG. 3 that the shield control arrangement 150 and the sensor control arrangement 170 are electrically connected to the same signal generator arrangement 130 and the same filter arrangement 140 via the control path KP. As a result, an electrical signal (the control signal) generated by the signal generator arrangement 130 and / or filtered by the filter arrangement 140 is used on the control path KP both for controlling the sensor element 20 and the shield element 160, preferably with an essentially identical signal form of the signal, preferably one at least approximately sinusoidal, so that an electrical potential difference between the sensor element 20 and the shield element 160 is always minimized during the operation of the arrangement 10 during the control and / or detection. The shield element 160 can be designed as an active shield element 160 (so-called “active shield”) for actively shielding the sensor element 20, so that an electrical potential on the shield element 160 actively tracks the electrical potential on the sensor element 20 by means of the shield control arrangement 150. This makes it possible to improve shielding of the sensor element 20 from the vehicle 1 and thus to reduce a load, that exists between the sensor element 20 and the vehicle 1. This load usually leads to a relatively large proportion of the evaluation signal, which is evaluated by the control device 300. The variable portion of the evaluation signal due to the changeable sensor capacity CS is thus reduced and can therefore only be evaluated with difficulty. A compensation arrangement 230 is optionally used to improve the evaluation. This branches z. B. depending on the amplitude of the evaluation signal, a part of the electrical current from the memory arrangement 250. The use of a shield element 160, which has the same potential for shielding as the sensor element 20, can further reduce the described difficulties in the evaluation.

The sensor element 20 can be repeatedly charged and discharged via the first connection 170.A of the sensor control arrangement 170 by means of the charge transfers. These repeated charges and discharges can be controlled by the control signal (due to a periodically changing voltage amplitude of the control signal). Depending on the charge transfers, an electrical sensor signal can be output via the second connection 170.B of the sensor control arrangement 170. It is possible for the sensor signal to be electrically filtered. Correspondingly, filtering for the evaluation branch during the transmission of the sensor signal to the memory arrangement 250 can be involved, which therefore has no influence on the electrical signal of the electrical control (on the control path KP) and thus on the charging of the sensor element 20. For this purpose, an evaluation filter arrangement 210 can be used to carry out filtering (such as, for example, bandpass filtering) of the electrical sensor signal. This enables the evaluation filter arrangement 210 to filter out disturbing immissions from the surroundings of the sensor element 20. The evaluation filter arrangement 210 can thus provide EMC filtering of immissions. For this purpose, the evaluation filter arrangement 210 z. B. a complex resistor and additional filter elements. It is conceivable that the described form (eg sinusoidal form) of the electrical signal of the electrical control on the control path KP (ie the control signal) relates to the electrical voltage of the signal. The voltage of the sensor signal at connection 170.B can have the same shape, but possibly an amplified amplitude (proportional to the sensor capacitance CS). However, the evaluation may depend on the charge transfer and thus the electrical current when the sensor signal is transferred to the memory arrangement 250. The evaluation filter arrangement 210 can therefore be one Have transconductance converters in order to carry out a transconductance conversion of the sensor signal at connection 170.B. Such a transconductance conversion is understood to mean that a voltage is converted into a current proportional to it. In other words, the evaluation filter arrangement 210 can be designed and / or connected in the evaluation arrangement 200 in such a way that an electrical current is generated from the voltage of the electrical signal (sensor signal) at the second connection 170.B in the form described (e.g. sinusoidal form) with this shape at the output 210.A of the evaluation filter arrangement 210 is formed. The transconductance converter is e.g. B. designed as a transconductance amplifier (using an operational amplifier), but preferably provides the transconductance conversion without an operational amplifier due to the interconnection with the memory arrangement 250. This is e.g. B. possible by the circuit configuration of the evaluation filter arrangement 210 in series with the memory arrangement 250. Furthermore, the downstream components 220, 250 can be low-resistance, and / or the storage arrangement 250, for. B. at input 250. B have the inverting input (-) of an amplifying element, and in particular operational amplifier. The reinforcing element of the memory arrangement 250 can be designed such that countermeasures are initiated immediately if a voltage occurs at the input 250. For this purpose, an operational amplifier can regulate the differential voltage of its inputs to zero by means of feedback. These precautions and / or the arrangement of the evaluation arrangement 200 in series with the memory arrangement 250 have the effect that almost no voltage drops at the input 250.B or output 210.A. In other words, there is almost a ground potential at this point (at the input 250. B or at the output 210. A, if these are connected to one another, for example via a switch of the rectifier arrangement 220), so that this point is regarded as a virtual zero point can be.

The block 220 shown in FIG. 3 can relate to one or more rectifiers, and thus a rectifier arrangement 220. The rectifier arrangement 220 can possibly do without diodes or the like, so that essentially no (or almost no) voltage drop occurs at the rectifier arrangement 220. This can be implemented, for example, by performing the rectification by means of at least one electronic switch which is switched in a clocked manner. In this way, when establishing the electrical connection between the output 210.A and the input 250.B, the rectifier arrangement 220 and in particular the at least one switch can provide a virtual zero point for the input 250.B or output 210.A ( if the switch is closed). If, on the other hand, the at least one switch is opened, the output 210.A of the evaluation filter arrangement 210 can be connected to a ground potential 21. E.g. For this purpose, the switch connects the output 210.A to the ground potential 21 as a changeover switch. In this way, a ground potential can always be present at the output 210.A at least approximately, regardless of the switch position of the at least one switch in the rectifier arrangement 220 Evaluation filter arrangement 210 significantly reduced.

The rectification described can be a “coherent” rectification by the at least one rectifier. This means that the at least one rectifier forwards the electrical signal (sensor signal) from the evaluation filter arrangement 210 to the memory arrangement 250, preferably in a phase-synchronized manner with the electrical control. This has the effect that the sensor signal is coherently rectified to the control signal. For this purpose, each of the rectifiers can have at least one electronic switch. The clock can in each case be predetermined in such a way that only positive (or alternatively negative) half-waves of a respectively predetermined fundamental or harmonic of the electrical signal (e.g. with the first harmonic as the fundamental of the frequency, which is generated by the evaluation filter arrangement 210 as the center frequency is allowed to pass through, and possibly further harmonics). The respective clock can therefore be synchronized with the signal generator arrangement 130 in order to be matched to the shape of the electrical signal (control signal) of the electrical control. Taking into account the filtering by the evaluation filter arrangement 210, the phase shift between voltage (corresponding to the electrical signal of the electrical control on the control path KP) and current (corresponding to the signal at the output 210.A of the evaluation filter arrangement 210) is taken into account in this synchronization. Furthermore, rectification can also be carried out “incoherently” using diodes.

It is also possible that the rectification takes place in the form of a one-way rectification, or alternatively that both the positive and the negative half-wave of the sensor signal are used for charge transfer to the memory arrangement 250.

In addition, it can be provided that a frequency of the sensor signal (as a periodic signal) is dependent on an operating frequency, ie the frequency of the Control signal at connection 170. C (or at the output of filter arrangement 140). Thus, a single operating frequency can be used for the entire arrangement 10 both for the activation and for the evaluation of the sensor element 20, in order to carry out the activation and evaluation of the sensor element 20 with a predetermined operating frequency range. For this purpose, filtering is used in the electrical control (by the filter arrangement 140) and in the evaluation (by the evaluation filter arrangement 210), the filtering being adapted to the working frequency (for example a low and / or bandpass to pass the working frequency range trains). This enables an optimal evaluation with regard to EMC conditions (for emissions) and interfering effects (for immissions).

FIG. 5 shows a possible embodiment of the arrangement 10 according to the invention when it is used with an elongated sensor element 20. Such a design is used, for example, when the sensor element 20 is to be used in a bumper 1.1 on a front or rear side of the vehicle 1. This makes it possible to detect a movement of the activation means 3 below the bumper 1.1 as an activation action, as is also illustrated in FIG. 6. In contrast to an embodiment of the sensor element 20 as a conductor track of a printed circuit board, as can be useful in the arrangement in the door handle 1.5 to provide a spatially rather limited detection area, a separate sensor element 20 is connected to the printed circuit board in the case of a larger detection area. For this purpose, e.g. B. a sensor element connection 180.A of the circuit board can be used, which provides an electrical connection to the switching element 180. This in turn can provide the electrical connection via the sensor control arrangement 170 and the control path KP and the filter arrangement 140 to the signal generator arrangement 130 (for charging) or via the evaluation filter arrangement 210 and the rectifier arrangement 220 to the memory arrangement 250 (for evaluation). The components 170, 140, 130, 210, 220, 250 mentioned can also be arranged on the circuit board.

The printed circuit board with the components, in other words the control arrangement 100 and / or the evaluation arrangement 200, can be understood as a common component, which is referred to below as the sensor switching arrangement 400. It is optionally possible for this sensor switching arrangement 400 to be designed as an individually manageable part that can be mounted on the vehicle. The sensor switching arrangement 400 can be used for Assembly of the arrangement 10 according to the invention can be electrically connected to the sensor element 20 and possibly to at least one further sensor element 20 ′ via at least one sensor feed line 410. The at least one further sensor element 20 ′ can in this case optionally be connected to the sensor switching arrangement 400 via at least one further sensor feed line 410. It is also optionally possible for the sensor switching arrangement 400 to be electrically connected to at least one shield element 160 or further shield element via a shield line 420, in particular shield feed line 420, or for the shield line 420 to form the shield element 160 (ie possibly also a further shield element).

As an exemplary embodiment of the arrangement 10 according to the invention, a coaxial cable 450 is shown schematically in FIG. 5, whose outer conductor 450.2 is used as a sensor element 20. In other words, the shield 450.2 of the coaxial cable 450 forms the sensor element 20. For this purpose, the sensor lead 410 can be electrically connected to the outer conductor 450.2 via the connection 180.A of the sensor switching arrangement 400. The connection 180.A transmits the electrical signal of the electrical control, which is predetermined (ie generated and possibly filtered) by the signal generator arrangement 130 and / or the filter arrangement 140 and can also be output by a sensor control arrangement 170 at the connection 180.A. In the same way, a shield lead 420 can be connected to a shield element 160 via a shield element connection 150.A of the sensor switching arrangement 400 (see FIG. 6) or the shield line 420 connected to the shield element connection 150.A itself the shield element 160 (or possibly also a further shield element ) form. In the latter case and shown in FIG. 5 in particular, it can be useful if the shield element 160 is operated as a passive shield element 160. The inner conductor 450.1 (i.e. the core) of the coaxial cable 450 can possibly remain disconnected.

When operating as a passive shield element 160, the shield element 160 is connected to a predetermined constant electrical potential via the shield element connection 150.A during operation (always or during the charging and / or discharging of the sensor element 20). The electrical potential of the shield element 160 can correspond to a ground potential 21 or be a different potential. In contrast to this, when operating as an active shield element 160, the electrical potential of the shield element 160 can be tracked and varied depending on the electrical potential of the sensor element 20. It is illustrated by an arrow in FIG. 5 that the leads 410, 420 can be twisted to mount the arrangement 10 according to the invention on the vehicle 1. First of all, the shield element 160 in the form of a shield line 420 as an elongated shield electrode 160 can run parallel to the sensor feed line 410. The twist can e.g. B. by twisting against each other and helically wrapping the sensor lead 410 with the shield line 420. The twisted supply lines 410, 420 are highlighted with a dashed and continuous line. In this way, the sensitivity to external electromagnetic interference on the leads 410, 420 can be reduced. Subsequently, the sensor feed line 410 can be electrically connected to the outer conductor 450.2 for assembly, so that the outer conductor 450.2 forms the sensor element 20. The shield line 420 and the core 450.1 of the coaxial cable 450 may remain disconnected. Alternatively, the shield line 420 is electrically connected to the core 450.1. With this configuration, it is advantageous if the shield element 160 is used as a passive shield element 160.

Alternatively, operation of the shield element 160 or the shield line 420 as an active shield element 160 also makes sense. For this purpose, a different connection on the coaxial cable 450 may be selected. The sensor supply line 410 can be electrically connected to the core 450.1 (ie the inner conductor 450.1) of the coaxial cable 450, so that the core 450.1 serves as a sensor supply line. The shield line 420, in this case possibly as a shield lead 420, can be electrically connected to the outer conductor 450.2 (i.e. with the shield) of the coaxial cable 450, so that the outer conductor 450.2 forms the active shield element 160. The coaxial cable 450 with the core 450.1 can serve as a lead to the sensor element 20, which, however, is then implemented separately from the coaxial cable 450. The outer conductor 450.2 acts as an active shield element 160 to improve the shielding of the sensor feed line 410. The feed line 410, 420 to the coaxial cable 450 can be twisted as described above, or it can be a parallel lead.

A separate sensor element 20, which, for. B. via the previously described twisted leads 410, 420 and / or via the coaxial cable 450 with the outer conductor 450.2 as an active shield element 160 and / or via a variant which deviates therefrom, with the Sensor switching arrangement 400 is connected is shown by way of example in FIG. 6. The sensor element 20 may e.g. B. as an electrically conductive surface (so-called flat electrode 20) and / or as an electrically conductive line or the like. The sensor element 20 is shown in an assembled arrangement (for example in the rear area) in the vicinity of further parts of the vehicle 1. Part of the vehicle 1 which can be regarded as ground potential 21 is indicated schematically. The vehicle 1 can cause a load on the sensor element 20, which can be counteracted by a shield. The electrical field is illustrated by arrows, which can occur between a shield element 160 and the sensor element 20 (and can be reduced or eliminated as far as possible by operating the shield element 160 as an active shield element 160) and which is used to record the activation action or the activating agent 3 is used.

The shape of the (active) shield element 160 shown is particularly advantageous. The shape is, for example, a U-shape, with the two opposite side parts 160.2 of the shield element 160 shielding a side region and a center part 160.1 of the shield element 160 shielding the center region or the vehicle side . In this way, the detection area can be defined very precisely by the open area 160.3 of the shield element 160 between the side parts 160.2. The shield element 160 can e.g. B. can be operated as an active shield element 160 in that it is electrically connected to the shield (to) line 420 or to an outer conductor 450.2 of the coaxial cable 450 (if this is used as a feed line). The sensor element 20 can also be electrically connected to the sensor lead 410 and / or to the core 450.1 of the coaxial cable 450 (if this is used as a lead). Alternatively, the shape can also be designed differently from a U shape, in particular if the shield element 160 is wider than the sensor element 20.

As can be seen from the schematic circuit diagram in FIG. 3, the sensor control arrangement 170, which is electrically connected to the sensor element 20, can provide the sensor signal at the connection 170.B which is specific for the parameter of the sensor element 20. The parameter is specific for the detected change in the environment, but possibly also for a variable load component. E.g. During the detection, depending on the environment and / or the arrangement of the sensor element 20 and / or interference from the environment, a certain influence on the sensor element 20 and on the parameter (such as the sensor capacitance CS), which has no meaningfulness with regard to the activation action. The sensor signal at connection 170.B is in particular a voltage, the amplitude of which can be dependent and possibly proportional to the sensor capacitance CS. Furthermore, the sensor signal at connection 250. B can be present as an electrical current, the current strength of which is dependent and possibly proportional to the sensor capacitance CS. The amplitude and / or the current intensity can possibly have a certain proportion due to the load component, which is not specific for the change in the environment. The compensation arrangement 230 can therefore be used to adapt the sensor signal in order to compensate for the load component. For this purpose, for example, a certain portion of each of the repeated charge transfers is derived by the sensor signal to the compensation arrangement 230. An adapted sensor signal is thus generated from the sensor signal. If necessary, the derivation can take place continuously. A connection arrangement 220 can, for evaluation purposes, electrically connect the memory arrangement 250 to the adapted sensor signal during the repeated determination (in particular dynamically).

FIG. 4 shows schematically that the compensation arrangement 230 can have a plurality of compensation stages. A first compensation stage 230.1 and a second compensation stage 230.2 are shown as examples. Since the load component can be variable (e.g. depending on a change in disturbing influences from the environment), it is possible to switch between the compensation stages in order to change the component which is then always dissipated in the sensor signal. The switchover can be initiated, for example, by means of the control device 300. In order to make the decision whether a switchover should be initiated, the control device 300 can e.g. B. evaluate the determined parameter.

The steps of a method according to the invention are visualized schematically in FIG. According to a first method step 501, the provision of a sensor signal can be carried out, the sensor signal being specific for a parameter of the sensor element 20, and the parameter being specific for the detected change in the environment and for a variable load component. The sensor signal can then be adjusted in accordance with a second method step 502 in order to compensate for the load component. Then, in a third method step 503, the parameter of the sensor element 20 can be repeatedly determined on the basis of the sensor signal by means of a memory arrangement 250, in order to thereby carry out the detection of the activation action. The third method step 503, that is to say performing the repeated determination, can also include the following step: initiating an electrical connection of the memory arrangement 250 with the adapted sensor signal (in particular dynamically) during the repeated determination.

The above explanation of the embodiments describes the present invention exclusively in the context of examples. Of course, if technically meaningful, individual features of the embodiments can be freely combined with one another without departing from the scope of the present invention.

Referen ce l i st

1 vehicle

1.1 bumpers

1.2 rear area

1.3 tailgate

1.4 side area

1.5 door handle

1.6 door

1.7 Front area

2 users

3 activators

5 identifiers

8 control unit

10 arrangement

20 sensor element, sensor electrode

20 ‘another sensor element

21 ground potential

100 control order

130 signal generator arrangement, signal generator

130.1 Digital-to-analog converter

140 filter arrangement, active filter, sine filter

140.1 operational amplifier

140.2 filter element

150 shield control arrangement

150.A shield element connection 150.1 operational amplifier

160 shield element

160.1 middle part

160.2 side part, thigh

160.3 Detection area, open area

170 sensor control arrangement, voltage follower 170. A first connection of 170

170.B second connection of 170

170.1 operational amplifier

170.2 filter element

180 switching element

180.A output of 180, sensor element connection

200 evaluation arrangement

210 evaluation filter arrangement

210. A first connection or output of 210

220 rectifier arrangement, connection arrangement 230 compensation arrangement

250 memory array, integrator

250. A first connection

250. B second connection, input

300 control device, microcontroller

400 sensor switching arrangement

410 sensor cable

420 shield cable 450 coaxial cables

450.1 Inner conductor, soul

450.2 outer conductor 501 first process step

502 second process step

503 third process step

CL storage capacity CS sensor capacity KP control path

Claims

Patent claims

1. Arrangement (10) for a vehicle (1) for the detection of an activation action for the activation of a function on the vehicle (1), in particular for the detection of an activation action in a front, side and / or rear area (1.7, 1.4, 1.2) of the vehicle (1) for activating an opening and / or unlocking of a flap (1.3, 1.6) on the vehicle (1), comprising:

at least one sensor element (20) for detecting a change, in particular an approach by an activation means (3), in an environment of the sensor element (20),

a control arrangement (100) which is electrically connected to the sensor element (20) in order to provide an electrical sensor signal which is specific for a parameter of the sensor element (20), the parameter in turn being specific for the detected change in the environment,

an evaluation arrangement (200) for repeatedly determining the parameter of the sensor element (20) by means of a transmission of the sensor signal to a memory arrangement (250) in order to carry out the detection of the activation action,

an evaluation filter arrangement (210) of the evaluation arrangement (200) for bandpass filtering and / or for transconductance conversion of the sensor signal for transmission to the memory arrangement (250).

2. Arrangement (10) according to claim 1,

characterized,

that the control arrangement (100) provides an activation signal for an electrical activation of the sensor element (20) in order to initiate charge transfers at the sensor element (20) by means of the activation signal, the evaluation filter arrangement (210) providing the bandpass filtering with a center frequency and bandwidth, which is adapted to a frequency and in particular signal form of the control signal, in order to avoid interference, preferably disruptive To suppress emissions to the arrangement (10) from the environment, during the repeated determination and / or during the transmission to the storage arrangement (250).

3. Arrangement (10) according to one of the preceding claims,

characterized,

that a sensor control arrangement (170) of the control arrangement (100) is electrically connected to the sensor element (20) in order to initiate charge transfers between the sensor element (20) and the sensor control arrangement (170) and to provide the sensor signal on the basis of the charge transfers, the evaluation filter arrangement (210) is electrically connected to the memory arrangement (250) and to the sensor control arrangement (170) in order to filter and transmit the filtered signal to the memory arrangement (250).

4. Arrangement (10) according to one of the preceding claims,

characterized,

that the memory arrangement (250) is connected in series with the evaluation filter arrangement (210) via an input (250. B), and an input resistance of the memory arrangement (250) is so low that a virtual zero point forms at the input (250. B), so that preferably the sensor signal, filtered by the evaluation filter arrangement (210), is present at the input (250.B) as an electrical current signal with the signal shape and / or frequency, which has an electrical voltage signal from the sensor element (20) and / or a control signal.

5. Arrangement (10) according to one of the preceding claims,

characterized,

that the evaluation filter arrangement (210) is designed as a passive or active filter.

6. Arrangement (10) according to one of the preceding claims,

characterized,

that the evaluation filter arrangement (210) has a bandwidth in the range from 100 kHz to 1 MHz, preferably 250 kHz to 450 kHz and / or a center frequency of essentially 333 kHz.

7. Arrangement (10) according to one of the preceding claims,

characterized,

that the control arrangement (100) has a filter arrangement (140), in particular an active filter (140) and / or a low-pass filter, in order to provide an electrical control signal for the electrical control of the sensor element (20) filtered, in particular low-pass filtered, and / or shaped, so that an emission of the sensor element (20) by the filter arrangement (140) is preferably adapted.

8. Arrangement (10) according to one of the preceding claims,

characterized,

that the control arrangement (100) has a filter arrangement (140), in particular an active filter (140), which connects a signal generator arrangement (130) via a control path (KP) to the sensor element (20) in order to be replaced by the signal generator arrangement (130) to provide the generated electrical control signal on the control path (KP), in particular low-pass filtered, and / or shaped for the sensor element (20), and thereby to provide it as a filtered electrical signal, preferably a sinusoidal signal.

9. Arrangement (10) according to one of the preceding claims,

characterized,

that the evaluation filter arrangement (210) is provided in addition to a filter arrangement (140) of the control arrangement (100) in order to additionally filter immissions on the sensor element (20) for determining the parameter, the filter arrangement (140) preferably for filtering a control signal for the sensor element (20) and the evaluation filter arrangement (210) are designed to filter the sensor signal for the memory arrangement (250).

10. Arrangement (10) according to one of the preceding claims,

characterized,

that the sensor element (20) is designed as a sensor electrode (20) in order to provide the parameter specific for the detection as a variable capacitance (CS), the change in the capacitance (CS) being specific for the change in the environment, the Arrangement (10) is designed for the repeated determination:

- to initiate repeated charge transfers by means of a control signal between the sensor element (20) and a sensor control arrangement (170), and as a function thereof

- repeatedly initiating charge transfers by means of the sensor signal between the sensor control arrangement (170) and the memory arrangement (250), in particular an integrator (250), of the evaluation arrangement (200),

so that the electrical charge stored by the storage arrangement (250) is specific to the change in capacitance (CS).

11. Arrangement (10) according to one of the preceding claims,

characterized,

that a control device (300) is connected to the memory arrangement (250) of the evaluation arrangement (200) in order to evaluate an electrical charge stored by the memory arrangement (250) in order to determine the parameter specific for the detection, preferably by an analog-digital conversion of a Voltage in the memory arrangement (250), preferably by an analog-digital converter of the control device (300).

12. Arrangement (10) according to one of the preceding claims,

characterized,

that the arrangement (10) as a capacitive sensor arrangement is at least partially integrated in a bumper (1.1) of the vehicle (1) in order to monitor the rear area (1.2) of the vehicle (1) and to function as the function on the vehicle (1) To open the tailgate (1.3) of the vehicle (1), in particular to initiate an output of an opening signal and / or an authentication check.

13. Arrangement (10) according to one of the preceding claims,

characterized,

that the arrangement (10) is designed to repeatedly charge and discharge the sensor element by electrically actuating the sensor element (20) and to carry out charge transfers by the sensor signal to the memory arrangement (250) as a function of this charging and / or discharging, wherein a control device (300), in particular at least one microcontroller, is electrically connected to a signal generator arrangement (130) in order to initiate the electrical activation in the signal generator arrangement (130) and / or is electrically connected to the memory arrangement (250) in order to a charge transfer to evaluate the amount of the charge stored in the storage arrangement (250) and / or accumulated after several charge transfers, and to carry out the detection based on the evaluation, preferably to output an activation signal for activating the function on the vehicle (1) if the charge amount is a limit value exceeds.

14. Arrangement (10) according to one of the preceding claims,

characterized,

that a sensor control arrangement (170) is electrically connected to the sensor element (20) in order to use an activation signal and / or charge transfers on the sensor element (20) to produce an electrical voltage signal with a specific frequency and / or signal shape, preferably a sinusoidal shape, at an output (170.B), the evaluation filter arrangement (210) being designed to convert the voltage signal into an electrical current signal with the essentially the same signal form and / or frequency for charge transfers to the storage arrangement (250), so that the sensor signal changes as that gives electrical current signal through the transconductance conversion, wherein preferably the signal shape and / or frequency of the voltage signal corresponds to the signal shape and / or frequency of the control signal.

15. Arrangement (10) according to one of the preceding claims,

characterized,

that a rectifier arrangement (220) is connected between the evaluation filter arrangement (210) and the memory arrangement (250), in order to forward charge transfers by the sensor signal in the direction of the memory arrangement (250) to the memory arrangement (250), and preferably only in this case, by repeated switching Forwarding to connect a virtual zero point (250.B) of the memory arrangement (250) to the evaluation filter arrangement (210) and in particular to a compensation arrangement (230), and preferably otherwise to connect the evaluation filter arrangement (210) to a ground potential (21).

16. Having system:

an arrangement (10) according to one of the preceding claims,

a control device (300) for outputting an activation signal in the case of

Detection of the activation action,

a control unit (8) which is connected to the control device (300) in order to carry out the function on the vehicle (1) when the activation signal is received.

17. Method for a vehicle (1) for the detection of an activation action for the activation of a function on the vehicle (1), in particular in a front, side and / or rear area (1.2, 1.4, 1.7) of the vehicle (1) for the Activation of an opening and / or unlocking of a flap (1.3, 1.6) on the vehicle (1), with a sensor element (20) for detecting a change, in particular an approach by an activation means (3), in an environment of the sensor element (20), following the steps below:

Providing an electrical sensor signal which is specific for a parameter of the sensor element (20), the parameter in turn being specific for the detected change in the environment,

Performing a repeated determination of the parameter of the sensor element (20) on the basis of a transmission of the sensor signal to a memory arrangement (250), performing bandpass filtering and / or transconductance conversion of the sensor signal for the transmission to the memory arrangement (250).

18. The method according to any one of the preceding claims,

characterized,

that an arrangement (10) is operated according to one of the preceding claims.