Capacitive sensor array and vehicle door with capacitive sensor array

Abstract

Capacitive sensor arrangement (1) for detecting at least one approaching object (2), wherein the sensor arrangement (1) comprises a main electrode (S) and a plurality of auxiliary electrodes (H) spaced apart from one another, and an evaluation unit (3), wherein - each main electrode (S) and each auxiliary electrode (H) has a predetermined capacitance and is connected to the evaluation unit (3), which detects changes in the capacitance of the respective main electrode (S) or auxiliary electrode (H), - the main electrode (S) and / or the auxiliary electrodes (H) is / are designed as a touch sensor(s) and / or as a proximity sensor(s). - the evaluation unit (3) is set up to monitor all electrodes (1.1 to 1.9) together in such a way that changes in the capacitances of the several auxiliary electrodes (H) and changes in the capacitance of the main electrode (S) are recorded and compared with each other and / or with predefined reference values, wherein the evaluation unit (3) is set up, - to determine and evaluate a time offset and / or sequence of changes in the capacitances of the main electrode (S) and / or the auxiliary electrodes (H) in such a way that a user gesture is detected, characterized in that the evaluation unit (3) is set up, - to detect the gesture as a swiping movement of the user's hand when the time offset exceeds a certain threshold and a predefined sequence of changes in the capacitances of the main electrode (S) and / or auxiliary electrodes (H) is determined by the evaluation unit (3), wherein the evaluation unit (3) is configured to activate a vehicle function (F) when a swiping movement or an actuation of the main electrode (S) is detected, wherein the activation of the vehicle function (F) includes automatically unlocking a vehicle door, automatically locking a vehicle door, automatically closing or opening a vehicle window, automatically opening or closing and locking a sliding door of the vehicle, and / or switching on a ventilation, seat heating, and / or auxiliary heating system, wherein the auxiliary electrodes (H) and the main electrode (S) are arranged in a circle,wherein the main electrode (S) is arranged centrally and the auxiliary electrodes (H) are each arranged adjacent to the main electrode (S) and are designed as circular arcs.

Description

[0001] The invention relates to a capacitive sensor arrangement for detecting at least one approaching object and a vehicle door with such a capacitive sensor arrangement.

[0002] Capacitive sensor arrangements are commonly known as proximity or touch sensors for capacitive touch detection, for example to detect an approaching hand or hand presence / operation on a handle, such as an exterior vehicle handle, and to enable or disable a function, such as a locking or unlocking function.

[0003] From DE 10 2017 215 333 A1, a capacitive sensor arrangement for detecting an approaching object is known, wherein the sensor arrangement comprises a plurality of electrodes, each designed as a planar electrode, which are aligned relative to and spaced apart from one another. Each electrode has a predetermined capacitance and is connected to an evaluation unit. One of the electrodes is a main electrode, and the other electrodes are auxiliary electrodes. Furthermore, the evaluation unit is configured to monitor all electrodes together in such a way that changes in the capacitances of the multiple auxiliary electrodes and changes in the capacitance of the main electrode are detected and compared with each other or with predetermined reference values.

[0004] From DE 10 2017 105 957 B3, an operating element for switching or controlling an electronic device is known, wherein the operating element has a surface with a first touch-sensitive area and a second touch-sensitive area, wherein the first touch-sensitive area and the second touch-sensitive area are spaced apart from each other such that the first touch-sensitive area and the second touch-sensitive area can each be contacted by each finger of two adjacent fingers of an operator's hand, and wherein a first tactile actuator is assigned to the first touch-sensitive area so that tactile information can be imprinted on one of the operator's fingers that contacts the first touch-sensitive area, wherein the operating element is configured in such a way thatthat when both touch-sensitive areas are contacted by a finger, the electronic device is switched or controlled and the tactile information is imprinted on the finger contacting the first touch-sensitive area.

[0005] The object of the present invention is to provide a capacitive sensor arrangement for detecting at least one approaching object, with which a user's gesture can be detected. Furthermore, a vehicle door with an improved capacitive sensor arrangement is to be provided.

[0006] The problem is solved according to the invention by a capacitive sensor arrangement with the features of claim 1. With regard to the vehicle door, the problem is solved according to the invention by the features of claim 5.

[0007] Advantageous embodiments of the invention are the subject of the dependent claims.

[0008] The capacitive sensor arrangement for detecting at least one approaching object comprises a main electrode, a plurality of auxiliary electrodes spaced apart from one another, and an evaluation unit, wherein each main and auxiliary electrode has a predetermined capacitance and is connected to the evaluation unit, which detects changes in the capacitance of the respective electrode, wherein the main electrode and / or the auxiliary electrodes are configured as a touch sensor(s) and / or as a proximity sensor(s), wherein the evaluation unit is configured to monitor all electrodes jointly such that changes in the capacitances of the multiple auxiliary electrodes and changes in the capacitance of the main electrode are detected and compared with each other.Furthermore, the evaluation unit is configured to determine and evaluate a time offset and / or sequence of changes in the capacitances of the main electrode and / or the auxiliary electrodes in such a way that a user gesture is detected, wherein the evaluation unit is configured to record the gesture as a swiping movement of the user's hand if the time offset exceeds a certain threshold and / or a previously specified sequence of changes in the capacitances of the main and / or auxiliary electrodes is determined by the evaluation unit.

[0009] According to the invention, the auxiliary electrodes and the main electrode are arranged in a circular pattern, with the main electrode being arranged centrally and the auxiliary electrodes being arranged adjacent to the main electrode and the auxiliary electrodes being designed as circular arcs.

[0010] The advantages achieved with the invention lie in the fact that, due to a combination of auxiliary electrodes and a main electrode, a measured or sensor signal from the main electrode can be checked for plausibility by the measured or sensor signals from the auxiliary electrodes. This check enables the reliable triggering or locking of a switching function, such as an unlocking or locking function, upon identified contact or approach of an object to the main electrode.

[0011] Furthermore, the invention offers the advantage that a time offset and / or sequence of changes in the capacitance of the main electrode and / or the auxiliary electrodes can be determined and evaluated, so that a user gesture can be detected. This detection of the gesture, for example a user's hand swiping motion, enables further vehicle functions, such as switching on the vehicle's ventilation, to be executed automatically.

[0012] In one possible embodiment, the evaluation unit is configured to detect activation of the main electrode based on the measured changes in the capacitance of the main electrode and / or auxiliary electrodes. The main electrode serves as the measuring electrode, which must be activated or touched to trigger a function. The auxiliary electrodes monitor the environment surrounding the main electrode. For example, the auxiliary electrodes detect false signals caused by mechanical stress such as dust, rain, or dirt, and suppress false activation of the main electrode. For instance, activation of the main electrode is detected when the change in capacitance of the main electrode exceeds a predefined threshold, and when changes in capacitance of the main electrodes do not exceed a predefined threshold.

[0013] A further development of the invention provides that the evaluation unit is configured to activate a vehicle function, for example, the automatic opening of a vehicle door, when a swiping motion or an actuation of the main electrode is detected. Such automatic activation of the function significantly increases user-friendliness and user satisfaction.

[0014] According to a further embodiment of the invention, the activation of the vehicle function includes automatically unlocking a vehicle door, automatically locking a vehicle door, automatically closing or opening a vehicle window, automatically opening or closing and locking a sliding door of the vehicle, and / or switching on ventilation, seat heating, and / or auxiliary heating. Thus, the sensor arrangement can, for example, activate several vehicle functions, thereby increasing ease of use.

[0015] Another embodiment provides that a vehicle door is automatically unlocked or locked when the activation of the main electrode is detected and the measured changes in the capacitance of the auxiliary electrodes do not exceed a predetermined threshold. For example, the main electrode can continue to be activated in the rain, even though the evaluation unit detects changes in the capacitance of the auxiliary electrodes.

[0016] Furthermore, a vehicle window will automatically close or open; a sliding door will automatically open or close and lock; and / or ventilation, seat heating, and / or auxiliary heating will be activated if the detected swiping motion matches a predefined swiping motion. For example, a downward swipe will automatically close the vehicle window.

[0017] The capacitive sensor arrangement is particularly suitable for use on vehicle doors, where an outer surface of the main electrode and / or an outer surface of the vehicle door on which the main electrode is located is designed to differ from an outer surface of the auxiliary electrodes, making the position of the main electrode easily identifiable by the user. For example, the outer surface of the vehicle door on which the main electrode is located has a different color than the outer surface of the auxiliary electrodes. This makes it easier for the user to recognize the sensor arrangement and to activate the main electrode or to correctly perform a swiping motion.

[0018] Exemplary embodiments of the invention are explained in more detail with reference to the drawings. These show: Fig. 1 schematically a possible embodiment of a capacitive sensor arrangement, Fig. 2 schematically another possible embodiment of the capacitive sensor arrangement and Fig. 3 schematically shows another possible embodiment of the capacitive sensor arrangement.

[0019] Corresponding parts are marked with the same reference symbols in all figures.

[0020] Fig. 1 to Fig. Figure 3 schematically shows exemplary embodiments of a capacitive sensor arrangement 1 for detecting an object 2 or a gesture of the object 2.

[0021] The capacitive sensor arrangement 1 comprises, for example, nine electrodes 1.1 to 1.9, each designed as a surface electrode and arranged in relation to and spaced apart from one another. The sensor arrangement 1 is, for example, mounted on a vehicle door, in particular on a vehicle door without a handle.

[0022] Each electrode 1.1 to 1.9 has a predetermined capacitance. Depending on the type and design of the electrodes 1.1 to 1.9, the capacitive sensor arrangement 1, or at least one of the electrodes 1.1 to 1.9, is configured as a touch sensor and / or as a proximity sensor that reacts to the approach and / or contact of the object 2, in particular by changing its capacitance. For example, the changing electrical capacitance of the electrode 1.1 to 1.9 is determined in comparison to the environment or to a reference electrode. For example, each electrode 1.1 to 1.9 is configured as part of an oscillator, in particular an LC resonant circuit, which changes its oscillation frequency when the object 2 approaches. Consequently, the changing capacitance can be determined.

[0023] Each electrode 1.1 to 1.9 is connected to an evaluation unit 3. The evaluation unit 3 is, for example, an integrated circuit or a microprocessor. The evaluation unit 3 detects, for example, the changes in capacitance or oscillation frequency of the respective electrode 1.1 to 1.9 as a measurement signal.

[0024] In a simple embodiment, one of the electrodes 1.1 is configured as the main electrode S. The other electrodes 1.2 to 1.9 are configured as auxiliary electrodes H or reference electrodes. The auxiliary electrodes H and / or the main electrode S are further configured as touch sensors and / or proximity sensors.

[0025] In the illustrated embodiments, the auxiliary electrodes H and the main electrode S are arranged in a circle, with the main electrode S positioned centrally and the auxiliary electrodes H each located adjacent to the main electrode S, and the auxiliary electrodes H being shaped as circular arcs. However, the auxiliary electrodes H and the main electrode S can also be arranged in another suitable shape, for example, in the form of a rectangle.

[0026] This arrangement of auxiliary electrodes H around the main electrode S enables at least partial monitoring and acquisition of the area surrounding the main electrode S. This allows the measurement signal of the main electrode S to be reliably verified and evaluated for plausibility by comparing the measurement signals of the auxiliary electrodes H and thus signals from the area surrounding the main electrode S.

[0027] In one embodiment, an outer surface AS of the main electrode S differs from an outer surface AH of the auxiliary electrodes H, so that the position of the main electrode S is recognizable to the user. For example, the surface color of the main electrode S and the auxiliary electrodes H differs. For example, the surface profile of the main electrode S differs from a surface profile of the auxiliary electrodes H and / or from an outer surface of the vehicle door on which the main electrode S is located.

[0028] Evaluation unit 3 is configured to monitor all electrodes 1.1 to 1.9 together. For this purpose, electrodes 1.1 to 1.9 are coupled to evaluation unit 3 in the conventional manner.

[0029] The evaluation unit 3 is set up in such a way that changes in the capacitances of the several auxiliary electrodes H and changes in the capacitance of the main electrode S are recorded and compared with each other.

[0030] Evaluation unit 3 is configured to detect activation of the main electrode S based on the determined changes in the capacitance of the main electrode S and / or auxiliary electrodes H. For example, activation of the main electrode S is detected when a hand or finger of a vehicle user touches a surface of the main electrode S.

[0031] To ensure the safe triggering or locking of a switching function, such as an unlocking or locking function, upon identified contact or approach of the object 2 to the main electrode S, the environment of the main electrode S is monitored by means of the auxiliary electrodes H.

[0032] The evaluation unit 3 monitors the changes in the capacitances of the auxiliary electrodes H and the main electrode S, for example, in such a way that false signals, which are caused, for example, by an influence, in particular a mechanical stress or exposure to dust, rain or dirt, are detected and a false triggering is suppressed by blocking or suppressing a triggering of function F.

[0033] If the capacitance of the main electrode S – electrode 1.1 – changes beyond the predefined reference value due to the presence of a hand as an approaching object 2, and thus more significantly than the changes in capacitance at the auxiliary electrodes H – electrodes 1.2 to 1.9 – then activation of the main electrode S is detected. Therefore, even in the event of rain, the evaluation unit 3 can reliably detect the approach or contact of a desired object 2.

[0034] Furthermore, the evaluation unit 3 is set up to determine a time offset and / or a sequence of changes in the capacitances of the main electrode S and / or the auxiliary electrodes H and to evaluate them in such a way that a gesture, for example of the user, is detected.

[0035] Furthermore, the evaluation unit 3 is set up to detect the gesture as a swiping movement of object 2, for example a swiping movement of a hand of the user of the vehicle, if the time offset exceeds a certain threshold and / or a previously specified sequence of changes in the capacitances of the main electrode S and / or the auxiliary electrodes H is determined by the evaluation unit 3.

[0036] The evaluation unit 3 of the exemplary embodiment in Fig. For example, device 1 detects a swiping motion from left to right if it first detects the change in capacitance of electrode 1.7, followed by changes in the capacitance of electrodes 1.4 and 1.5, electrode 1.1, electrodes 1.2 and 1.3, and finally electrode 1.6. Similarly, it is possible to detect a swiping motion from right to left, from top to bottom, from bottom to top, or diagonally.

[0037] Evaluation unit 3 can activate a function F when it detects a swiping motion or actuation of the main electrode S. For example, evaluation unit 3 generates a control signal SI to trigger or disable the corresponding function F.

[0038] Activating function F includes, for example, automatically unlocking a vehicle door, automatically locking a vehicle door, automatically closing or opening a vehicle window; automatically opening or closing and locking a sliding door of the vehicle and / or switching on ventilation, seat heating and / or auxiliary heating.

[0039] Evaluation unit 3 unlocks or locks, for example, a vehicle door when the activation of the main electrode S is detected and the measured changes in the capacitance of the auxiliary electrodes H do not exceed a predefined threshold. The measured values ​​of electrodes 1.1 to 1.9 can be compared with each other. Additionally, the measured values ​​of electrodes 1.1 to 1.9 can also be compared with threshold values ​​stored for each electrode 1.1 to 1.9. Multiple threshold values ​​can be stored for each electrode 1.1 to 1.9 to allow for differentiated detection of objects 2. For example, the main electrode S can still be activated by object 2 in the rain, even though evaluation unit 3 has detected changes in the capacitance of the auxiliary electrodes H.

[0040] In one embodiment, the evaluation unit 3 automatically opens or closes a vehicle window and / or automatically opens, closes, and locks a vehicle sliding door and / or switches a ventilation system, seat heating, and / or auxiliary heater on or off when a swiping motion detected by the evaluation unit 3 matches a predefined swiping motion. For example, the vehicle window closes automatically with a swipe from bottom to top. For example, the sliding door closes and locks automatically with a swipe from left to right.

[0041] Furthermore, the detection accuracy of the wiping motion can be influenced by the sensor geometry and / or by the arrangement of the main electrode S and the auxiliary electrodes H. For example, the exemplary embodiment in Fig. 3. Due to a higher number of auxiliary electrodes H and their arrangement, a higher detection accuracy is achieved than in the embodiments in Fig. 1 and Fig. 2. REFERENCE MARK LIST 1 Sensor arrangement 1.1 to 1.9 Electrode 2 objects 3 evaluation unit F function H Auxiliary electrodes S Main electrode AH Outer surface Auxiliary electrode AS outer surface main electrode SI control signal

Claims

[1] Capacitive sensor arrangement (1) for detecting at least one approaching object (2), wherein the sensor arrangement (1) comprises a main electrode (S) and a plurality of auxiliary electrodes (H) arranged at a distance from one another, and an evaluation unit (3), wherein - each main electrode (S) and each auxiliary electrode (H) has a predetermined capacitance and is connected to the evaluation unit (3), which detects changes in the capacitance of the respective main electrode (S) or auxiliary electrode (H), - the main electrode (S) and / or the auxiliary electrodes (H) are designed as a touch sensor(s) and / or as a proximity sensor(s) - the evaluation unit (3) is designed to monitor all electrodes (1.1 to 1.9) together in such a way that changes in the capacitances of the plurality of auxiliary electrodes (H) and changes in the capacitance of the main electrode (S) are recorded and compared with one another and / or with predetermined reference values, wherein the evaluation unit (3) is designed, - to determine a temporal offset and / or a sequence of changes in the capacitances of the main electrode (S) and / or the auxiliary electrodes (H) and to evaluate them in such a way that a gesture of a user is detected, characterized by that the evaluation unit (3) is set up, - to detect the gesture as a swiping movement of a user's hand if the time offset exceeds a certain threshold value and a predetermined sequence of changes in the capacitances of the main electrode (S) and / or auxiliary electrodes (H) is determined by the evaluation unit (3), wherein the evaluation unit (3) is configured to activate a vehicle function (F) if a swiping movement or actuation of the main electrode (S) is detected, wherein the activation of the vehicle function (F) comprises automatically unlocking a vehicle door, automatically locking a vehicle door, automatically closing or opening a vehicle window, automatically opening or closing and locking a sliding door of the vehicle, and / or switching on ventilation, seat heating, and / or auxiliary heating, wherein the auxiliary electrodes (H) and the main electrode (S) are arranged in a circle,wherein the main electrode (S) is arranged centrally and the auxiliary electrodes (H) are each arranged adjacent to the main electrode (S) and are formed as circular arcs., [2] Capacitive sensor arrangement (1) according to claim 1, wherein the evaluation unit (3) is configured to detect an actuation of the main electrode (S) as a function of the determined changes in the capacitance of the main electrode (S) and / or auxiliary electrodes (H). [3] Capacitive sensor arrangement (1) according to claim 2, wherein the evaluation unit (3) is configured to detect an actuation of the main electrode (S) if the determined change in the capacitance of the main electrode (S) exceeds a predetermined threshold value and the determined changes in the capacitance of the auxiliary electrodes (H) do not exceed a predetermined threshold value. [4] Capacitive sensor arrangement (1) according to one of the preceding claims, wherein a vehicle window is automatically closed or opened; a sliding door of the vehicle is automatically opened or closed and locked; and / or ventilation, seat heating and / or auxiliary heating is switched on when a detected wiping movement corresponds to a predetermined wiping movement. [5] Vehicle door with a capacitive sensor arrangement (1) according to one of the preceding claims, wherein an outer surface (AS) of the main electrode (S) and / or an outer surface of the vehicle door on which the main electrode (S) is arranged is designed such that it differs from an outer surface (AH) of the auxiliary electrodes (H), so that a position of the main electrode (S) can be recognized by the user.

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