Steering wheel arrangement, vehicle with the steering wheel arrangement, and method for checking a skeleton connection in the steering wheel arrangement

Description

[0001] The invention relates to a steering wheel assembly, a vehicle with the steering wheel assembly, and a method for checking a skeletal connection of the steering wheel assembly.

[0002] In semi-autonomous or fully autonomous driving systems, monitoring whether a driver is holding the steering wheel or leaving it unattended is crucial for driving safety. Hands-off detection (HOD) systems are now widely installed and often rely on measuring the steering wheel's capacitance, which changes when at least one hand is placed on it.

[0003] German patent application DE 102014223128 A1 discloses a steering wheel with a sensor assembly for detecting occupancy of a heated contact surface, comprising: a contact surface that forms at least a part of the outer layer of the steering wheel; a steering wheel skeleton; a sensor section in which at least one sensor electrode for occupancy detection and at least one heating wire are arranged; and a potential layer that is arranged between the sensor heating layer and the steering wheel skeleton, wherein a defined potential can be applied to the potential layer.

[0004] Furthermore, a steering wheel arrangement with the features in the preamble of claim 1 is known from generic US 2021 / 270637 A1.

[0005] It is an object of the invention to propose a steering wheel assembly whose status can be checked simply and cost-effectively. This object is achieved by a steering wheel assembly with the features of claim 1, by a vehicle with the features of claim 10, and by a method for checking a skeletal connection with the features of claim 11. Advantageous or preferred embodiments of the invention will become apparent from the dependent claims, the following description, and the figures.

[0006] The invention relates to a steering wheel assembly suitable for or designed for use in a vehicle. The vehicle can be a passenger car, a truck, but also a bicycle, tricycle, two-wheeler, etc.

[0007] The steering wheel assembly includes a steering mechanism, which preferably comprises a steering wheel rim, also called a steering wheel ring, which is particularly round. However, it is also possible for the steering mechanism to be reduced to two grip areas and / or designed in the shape of a figure eight. Furthermore, it is possible for the steering mechanism to be designed as a handlebar with two handlebar ends or horns. In particular, the steering mechanism is designed as a human-machine interface through which the driver of the vehicle mechanically transmits a steering command to the vehicle.

[0008] The steering mechanism includes a steering wheel frame. The steering wheel frame is preferably made of a metallic material. For example, the steering wheel frame is made of an aluminum alloy and / or a magnesium alloy. The steering wheel frame includes, for example, the steering wheel rim, which is connected to a hub via spokes. The steering wheel rim, the spokes, and the hub together form the steering wheel frame.

[0009] Furthermore, the steering wheel assembly comprises a first guide layer and a second guide layer. Each guide layer forms at least one conductive conductor section. The conductive conductor section can be configured as a single conductor, a conductor grid, or the like. Preferably, the conductive conductor section is integrated into a grip area of ​​the steering wheel assembly. For example, the conductive conductor section comprises a metallic conductor. Preferably, the first guide layer, the second guide layer, and the steering wheel frame are arranged concentrically and / or layer by layer in a cross-section relative to each other, with the second guide layer being arranged, particularly in a grip area of ​​the steering wheel frame and / or at the rim of the steering wheel frame, between the first guide layer and the steering wheel frame.

[0010] An intermediate layer capacitance is formed between the first and second conductor layers. In particular, the first and second conductor layers form an intermediate layer capacitor.

[0011] A skeletal capacitor is formed between the second guide layer and the steering wheel frame. In particular, the second guide layer and the steering wheel frame form a skeletal capacitor, or at least partially form one.

[0012] The steering wheel frame is coupled to the vehicle's ground via a skeletal connection. This connection can be galvanically linked to the vehicle's ground. Alternatively, a connection capacitance, preferably a connection capacitor, is arranged in the skeletal connection to the vehicle's ground. Preferably, the connection capacitance is at least 10 times greater than the intermediate layer capacitance or the frame capacitance. From a structural perspective, the skeletal connection preferably includes a cable section, which is connected to the steering wheel assembly and can be connected to the vehicle. Optionally, the ground capacitance is arranged in series within, before, or after the cable section and / or is particularly preferably designed as a capacitor component or capacitor component group.

[0013] The interlayer capacitance and the skeletal capacitance together form a capacitive voltage divider for the voltage applied to the first conductor layer. Due to this capacitive voltage division, a partial voltage, particularly of the voltage applied to the first conductor layer, is applied to the second conductor layer, allowing it to be tapped. The second conductor layer, in particular, forms a center tap on the capacitive voltage divider.

[0014] Within the scope of the invention, it is proposed that the steering wheel assembly includes an evaluation unit. In particular, the evaluation unit is designed as a digital data processing unit. Optionally, the evaluation unit can also include analog components. Alternatively, the evaluation unit is implemented as an analog circuit.

[0015] The evaluation unit is specifically designed, in terms of software and / or circuitry, to detect the partial voltage at the second conductor layer and, based on this detection, to assess the stator connection as OK (iO) or not OK (niO). The partial voltage can be represented as a voltage value, e.g., in volts. Alternatively, the partial voltage can be represented as an analog or digital reference value to the voltage value. The stator connection can also be coupled to the vehicle's ground via the evaluation unit.

[0016] The assessment can be output as a control signal to a monitoring unit for further processing and / or displayed to the driver as a light signal.

[0017] One aspect of the invention is that the basic design of such a steering wheel assembly already incorporates all the components of a capacitive voltage divider. Furthermore, the invention recognizes that in the event of a defect in the skeletal connection, the voltage conditions in the capacitive voltage divider change so significantly that such a defect can be reliably detected in a simple manner by checking the partial voltage or a reference value based on the partial voltage.

[0018] A further consideration of the invention is that conventional hand recognition devices operate on a capacitive basis, with the capacitance depending on the steering wheel frame coupled to ground. If the frame connection is defective or, for example, missing due to incorrect assembly, hand recognition via the hand recognition device cannot be performed, or at least not reliably. The steering wheel arrangement according to the invention allows the status of the steering wheel arrangement with regard to the frame connection to be checked reliably and cost-effectively, without or with only minimal additional hardware.

[0019] In a preferred embodiment of the invention, the steering wheel assembly includes a control unit. The control unit is preferably configured as a digital data processing unit. Alternatively, the control unit can also include analog components. Alternatively, the control unit can be configured as an analog circuit. The control unit is preferably configured, either programmatically or circuit-wise, to bring the first control layer and the second control layer into a defined initial voltage state in a first phase. It is possible for the initial voltage state to be different for the two control layers. However, it is preferred that the voltage state be the same for both control layers.

[0020] The control unit is further configured, particularly through programming and / or circuitry, to decouple the second conductor layer in a second phase, in particular to a high impedance, specifically such that a floating potential results in the first conductor layer, and to bring the first conductor layer into a second voltage state, wherein the second voltage state differs from the first voltage state. The evaluation unit is configured, particularly through programming and / or circuitry, to measure the partial voltage in the second phase.

[0021] In the first phase, both conductor layers are set to a defined potential. In the second phase, the first conductor layer is decoupled and / or subjected to a high resistance, specifically such that a floating potential results in the first conductor layer, while the second conductor layer is set to a different potential. Due to the arrangement as a capacitive voltage divider, the partial voltage in the second conductor layer changes depending on the applied capacitances. In particular, the skeletal capacitance differs between a defective and a functioning skeletal connection, so that the skeletal connection can be assessed as either good or bad based on the measured partial voltage.

[0022] In one possible embodiment of the invention, the first and / or second conductor layer is connected to ground in the first voltage state. In the second voltage state and / or in the second phase, a DC voltage is applied to the first conductor layer. Preferably, the second conductor layer is electrically insulated. This dynamic change in voltage states results in a change in the partial voltage, which can be measured by the evaluation device.

[0023] In an alternative embodiment of the invention, the first voltage state corresponds to a DC voltage, wherein, after disconnecting the second conductor layer and setting it to high resistance, the second voltage state of the first conductor layer corresponds to another DC voltage or to ground. In this process sequence as well, a defect in the skeleton connection can be reliably detected via the partial voltage.

[0024] The assessment of the partial stress in relation to the status of the skeletal connection (OK / not OK) can be carried out, for example, by comparing the partial stress with a stored, in particular predefined or learned, reference value.

[0025] Optionally, the steering wheel assembly has an ambient capacitance, wherein the ambient capacitance is formed between the first guide layer and the steering wheel skeleton.

[0026] In one possible embodiment of the invention, the evaluation unit and the control unit are designed as a single data processing device. In particular, these are designed as a single ECU and / or as a single chip, specifically a microcontroller, or as a single chip on a single ECU. By designing it as a single data processing device, the monitoring of the skeletal connection can be implemented particularly cost-effectively.

[0027] It is particularly advantageous that the connection of the first conductor layer is configured as a first GPIO and / or the connection of the second conductor layer as a second GPIO on the common data processing device (GPIO = General-purpose input / output). Such interfaces are inexpensive to implement on the chip or are already abundant, so that the hardware implementation can be realized at virtually no cost.

[0028] In a preferred, near-product implementation, the first layer is configured as a sensor layer for a Hands Off Detection (HOD) function. In particular, the steering wheel assembly includes a hand detection device for implementing the HOD function. The hand detection device is specifically designed as a capacitive hand detection device. As already explained, with a capacitive hand detection device, defining the potential at the steering wheel frame is particularly important for reliable hand detection. The steering wheel assembly according to the invention allows the status of the steering wheel assembly, especially the status of the frame connection, to be reliably checked, thereby ensuring the HOD function. For example, if the frame connection is deemed faulty, the hand detection device can be classified as defective or inactive.

[0029] In a preferred embodiment of the invention, the hand recognition device is integrated into the common data processing device, particularly the common chip. This embodiment further emphasizes the advantage that the functionality of the skeletal connection can be verified in a virtually hardware-neutral manner.

[0030] In principle, the steering wheel assembly can be limited to two guide layers. In a possible alternative of the invention, the steering wheel assembly has at least or exactly one third guide layer, wherein the third guide layer is arranged between the second guide layer and the steering wheel frame. The frame capacitance is then formed by a single capacitance between the second and third guide layers and a second single capacitance between the third guide layer and the steering wheel frame. Preferably, the third guide layer is configured as a heating layer.

[0031] It may be provided that the second conductor layer is designed as a heating layer and / or as a guard layer for checking the functionality of the first conductor layer / sensor layer.

[0032] Another object relates to a vehicle, wherein the vehicle has the steering wheel assembly. A further object of the invention relates to a method for checking the skeletal connection with the steering wheel assembly as previously described, wherein the partial stress at the second conductor layer is detected and, based on the detected partial stress, the skeletal connection is judged as either OK or not OK.

[0033] Further features, advantages and effects of the invention will become apparent from the following exemplary embodiments and the accompanying figures: Figure 1 a schematic representation of a steering wheel arrangement as an embodiment of the invention; Figures 2a , b , cEquivalent circuit diagrams of a first embodiment of the steering wheel arrangement in the Figure 1 in a basic phase, first phase and second phase to illustrate the procedure; Figure 3 an equivalent circuit diagram of a second embodiment of the steering wheel arrangement in the Figure 1 in a basic phase.

[0034] The Figure 1 Figure 1 shows a schematic representation of a steering wheel arrangement 1 with a steering wheel assembly 2 as an embodiment of the invention. The steering wheel assembly 2 serves to steer a vehicle (not shown).

[0035] The steering mechanism 2 comprises a steering wheel frame 3 with – in this embodiment – ​​a circumferential steering wheel rim 4 (or steering ring), which is schematically shown in a longitudinal section with its positions. The steering wheel rim 4 can be formed integrally with the steering wheel frame 3; alternatively, the steering wheel rim 4 and the steering wheel frame 3 are two separate components that are, however, electrically connected to each other.

[0036] An outer spacer layer 5, such as a leather or plastic covering, is arranged on the steering wheel rim 4. Adjacent to or adjacent to this is a first conductive layer 6, which optionally forms a sensor layer 7. Separated by an insulating layer, a second conductive layer 8 is arranged. The layered structure is electrically insulated from the steering wheel rim 4 and thus from the steering wheel frame 3 by a foam layer 9. The first conductive layer 6 and the second conductive layer 8 are – as can be seen on the left side of the Figure 1 This can be seen in a cross-section through the steering wheel assembly 2 – arranged concentrically around the steering wheel rim 4 and thus around the steering wheel frame 3 in a grip area for the driver. Other insulating layers can also be used.

[0037] The cross-section shown reveals that the first conductor layer 6 and / or the second conductor layer 8 is formed by a conductive wire wound around the steering wheel rim 4. Thus, the first and / or the second conductor layer 6, 8 forms at least one conductive sensor section.

[0038] An intermediate layer capacitance C_Layer_12 is formed between the first guide layer 6 and the second guide layer 8. A skeletal capacitance C_Skeleton is formed between the second guide layer 8 and the steering wheel skeleton 3. Optionally, an ambient capacitance C_Layer_1amb can be formed between the steering wheel skeleton 3 and the first guide layer 6.

[0039] The steering wheel assembly 1 includes a digital data processing device 10, which is implemented, for example, as an ECU, wherein the first control layer 6 is connected to a first terminal 11 of the digital data processing device 10, such that a voltage V_Layer_1 is applied to or provided at the first terminal 11. The second control layer 8 is connected via a second terminal 12 of the digital data processing device 10, such that a voltage V_Layer_2 is applied to or provided at the second terminal 12.

[0040] The steering wheel frame 3, and in particular the steering wheel rim 4, is connected via a skeleton connection 13 to a third terminal 14 of the digital data processing devices 10, such that a voltage V_Skeleton is applied to the third terminal 14. The third terminal 14 is connected or connectable to a vehicle ground, so that the steering wheel frame 3 is coupled to ground via the skeleton connection 13. Alternatively, the skeleton connection 13 is coupled or connectable to ground without the digital data processing device 10. The skeleton connection 13 is, for example, designed as a cable.

[0041] The Figures 2a , b , c Each shows an equivalent circuit diagram of the steering wheel arrangement 1 in the Figure 1, where the same components are provided with the same reference numerals or designations. Additionally, a vehicle capacitance C_Skel2chass is shown, which describes the capacitance between the vehicle and the steering wheel frame 3. Galvanic isolation from the vehicle's ground is preferably provided.

[0042] The digital data processing device 10 has four switches S1...S4, where switch S1 connects the first conductor 6 and switch S2 connects the second conductor 8 to ground M. Switch S3 connects the first conductor 6 to a DC voltage Vdd, for example, a supply voltage, and switch S4 connects the second conductor 8 to an analog-to-digital converter (ADC). "Connect" means that the respective switch establishes a conductive connection when closed and is open when open. Switches S1...S4 primarily serve to illustrate the function and can also be configured as double switches, changeover switches, etc.

[0043] The Figure 2a This shows a possible basic phase P0, where all switches S1...S4 are open. This basic phase is not mandatory.

[0044] In the basic phase P0, all switches S1...S4 are open, so that the first conductor layer 6 and the second conductor layer 8 are electrically isolated and connected to the digital data processing device 10. The basic phase P0 is not mandatory but is optional.

[0045] The Figure 2b Figure 1 shows a first phase P1, in which switches S1 and S2 are closed and switches S3 and S4 are open. The first conductor layer 6 and the second conductor layer 8 are connected to the ground M of the digital data processing unit 10. The skeleton connection 13 is connected to the same ground M in the digital data processing unit 10. Optionally, the ground M of the digital data processing unit 10 is conductively connected to a ground of the vehicle. In the first phase P1, the first conductor layer 6 and the second conductor layer 8 are thus brought to a common initial voltage state, namely ground M.

[0046] The Figure 2c Figure 2 shows a second phase P2, with switches S1 and S2 open. After switches S1 and S2 open, switches S3 and S4 close. Thus, the DC voltage Vdd, for example 5 V, is applied to the first layer 6. The second layer 8, on the other hand, has a high impedance and is connected to the analog-to-digital converter (ADC).

[0047] The switch between the first phase P1 and the second phase P2 results in a partial voltage being present in the capacitive divider, which is defined by the intermediate layer capacitance C_Layer_12 and the skeletal capacitance C_Skeleton at the center tap formed by the second conductor layer 8. This partial voltage is measured by the analog-to-digital converter (ADC).

[0048] If the skeletal connection 13 is OK (iO), a reference value for this partial voltage is obtained. This reference value is stored in the digital data processing unit 10. If the skeletal connection 13 is defective, i.e., not OK (niO), a different value is obtained for the partial voltage. For example, the skeletal connection 13 is not OK in its configuration as a cable if the cable is broken or not connected. By comparing the partial voltage in the second phase P2 with the previously determined reference value, a defect in the skeletal connection 13 can thus be reliably determined.

[0049] The digital data processing device 10 functionally comprises a control unit 15, which controls the actuation of switches S1...S4. Furthermore, the digital data processing device 10 includes an evaluation unit 16, wherein the evaluation unit 16 measures the partial voltage using the analog-to-digital converter (ADC) and performs an assessment by comparison with the reference value as to whether the skeleton connection 13 is OK or not OK (OK / NOK). Optionally, the digital data processing device 10 includes a hand detection device 17, wherein the hand detection device 17 uses the first position 6 as the sensor position 7 and determines via a capacitive measurement whether the driver is holding a hand on the steering wheel assembly 2, in particular on the steering wheel rim 4, specifically within the grip area of ​​the steering wheel rim 4, or whether the driver is not touching the steering wheel assembly 2 or the steering wheel rim 4.For example, the assessment of the evaluation unit 16 can be forwarded to the hand recognition devices 17, whereby if the skeleton connection 13 is assessed as not OK (NIO), the hand recognition devices 17 are classified as not ready for use and / or, for example, an error message is displayed to the driver via an optical signaling device (not shown).

[0050] The first pin 11 and the second pin 12 can each be configured as a GPIO (general purpose input / output), with the functions of connecting to ground M of the digital data processing device 10, connecting to the DC voltage Vdd, and / or connecting to the analog-to-digital converter ADC being implemented circuit-wise by the GPIOs. Such GPIOs are either already present in typical chips, especially microcontrollers, or can be implemented very cost-effectively, so that monitoring of the skeleton connection 13 can be implemented virtually hardware-neutrally and therefore cost-neutrally. In particular, the digital data processing device 10 is configured as a microcontroller with the GPIOs.

[0051] The Figure 3 shows an equivalent circuit diagram of the steering wheel arrangement 1 in the Figure 1in a modified embodiment, wherein the skeleton connection 13 is connected to the mass of the digital data processing device 10 and / or the mass of the vehicle via a connection capacitance C_SekI2ECU.

[0052] The following is a model calculation showing how the difference between the reference value of the partial stress and the partial stress in a skeleton joint 13, which is not in order, is calculated: Phase P1: In the first phase P1, VLayer_1 and VLayer_2 are set to zero voltage relative to ECU ground (ground M). Phase P2 with intact skeleton connection 13: In phase 2, VLayer_1 and VLayer_2 are first disconnected from ECU ground (ground M). Then, VLayer_1 is connected to the DC voltage VDD of the ECU, i.e., the digital data processing device 10, and after a short charging period, the following partial voltage is established at VLayer_2, which forms the reference value: V Layer _ 2 = V DD C Layer _ 12 C Skeleton + C Layer _ 12 Phase P2 with interrupted skeleton connection 13: If the connection from steering wheel skeleton 3 to ECU Gnd (ground) is interrupted, then in phase P2, after recharging, a voltage other than 0 (ground M) is established at the now interrupted skeleton connection 13 on the steering wheel skeleton side: V Skleleton broke = V DD C Layer 1 amb + C Layer 12 C Skleton C Skel 2 Chass + C Layer 1 amb + C Layer 12 C Skleton mit C Layer _ 12 C Skleton = C Layer _ 12 ∗ C Skleton C Layer _ 12 + C Skleton

[0053] For the measured partial voltage at the second conductor layer 8, the following results are obtained with an interrupted skeleton connection 13: V Layer _ 2 = V DD − V Skleleton _ broke C Layer _ 12 C Skeleton + C Layer _ 12 Δ V Layer 2 = V DD − V Skleleton broke C Layer 12 C Skeleton + C Layer 12 − V DD C Layer 12 C Skeleton + C Layer 12 = − V Skleleton _ broke C Layer _ 12 C Skeleton + C Layer _ 12 Δ V Layer _ 2 = − V DD 1 1 + C Skel 2 Chass C Layer _ 1 amb + C Layer _ 12 C Skleton C Layer _ 12 C Skeleton + C Layer _ 12

[0054] For typical steering wheel applications such as in the Figure 1 can be assumed based on geometric conditions: C Skel 2 Chass < C Layer _ 1 amb < C Layer _ 12 und C Skeleton 1 3 C Skeleton < C Layer _ 12 < 3 C Skeleton

[0055] This means the following for steering wheel applications: 5 36 V DD < Δ V Layer _ 2 < 21 44 V DD

[0056] This means that in all common steering wheel configurations the interrupted skeleton connection 13 to the steering wheel skeleton 3 can be reliably measured, as it has a voltage difference of at least 5 / 36 V_DD at the second connection 12 of the second conductor layer 8 / Layer_2. Example:

[0057] For a 10-bit analog-to-digital converter (ADC), the loss of the skeleton connection results in a difference of at least 5 / 36 * 1023 bits = 142 bits in the sampling of VLayer_2.

[0058] The following table lists various applications of skeleton diagnostics. It should be noted that in layers where the HOD and heating functions are shared with the skeleton diagnostics, the two functions cannot be executed simultaneously. HOD and skeleton diagnostics therefore require their own time windows in which the function is performed. With the three-layer system, the heating can be performed simultaneously with the skeleton diagnostics. This requires that the second electrical layer has a capacitive connection to the steering wheel skeleton 3. This is always the case when the heating layer does not form a closed sphere around the steering wheel skeleton 3. During evaluation, only switching transients of the heating need to be considered, which can be eliminated by multiple sampling. Table: Application possibilities of skeleton diagnostics in different steering wheel configurations steering wheel assembly Function of the electrically conductive layers in the steering wheel Skeleton Broken Diagnosis Two-layer HOD Double-layer HOD / heating Double-layer HOD / heating Three-layer HOD / heating First electrically conductive layer 6 Layer 1 HOD Sensor HOD Sensor HOD Sensor HOD Sensor Second electrically conductive layer 8 Layer 2 HOD Support Situation (Guard) Heating Heating / HOD Auxiliary Position (Guard) HOD Support Situation (Guard) Third electrically conductive layer - - - Heating Steering wheel frame Skeleton Skeleton Skeleton Skeleton Skeleton

[0059] Galvanic separation in the skeletal connection 13 according to Figure 3 : Is the connection to the steering wheel skeleton 13 via the capacity CSkle2ECU ( Figure 3 If the function is performed as described above, the preceding formulas apply with minor deviations as soon as the capacitance is much larger (>ten times) than the other capacitances involved. Therefore, the diagnosis of the loss of the skeleton connection 13 also works reliably with capacitive coupling. Reference sign

[0060] 1 Steering wheel assembly 2 Steering wheel device 3 Steering wheel skeleton 4 Steering wheel rim 5 Outer spacer layer 6 First guide layer 7 Sensor layer 8 Second guide layer 9 Foam layer 10 Digital data processing device 11 First connection of the digital data processing device 12 Second connection of the digital data processing device 13 Skeleton connection 14 Third connection of the digital data processing device 15 Control unit 16 Evaluation unit 17 Hand detection device P0 Basic phase P1 First phase P2 Second phase S1...S4 Switch C_Layer_12 Intermediate layer capacitance C_Skeleton Skeleton capacitance C_Layer_1amb Ambient capacitance C_Skel2chass Vehicle capacitance C_SekI2ECUA Connection capacitance MMass

Claims

1. A steering wheel arrangement (1) for a vehicle, comprising a steering wheel device (2), the steering wheel device (2) including - a steering wheel skeleton (3), - a first conductive layer (6), and - a second conductive layer (8), wherein an intermediate layer capacity (C_Layer_12) is formed between the first conductive layer (6) and the second conductive layer (8), wherein a skeleton capacity (C_Skeleton) is formed between the second conductive layer (6) and the steering wheel skeleton (3), wherein the steering wheel skeleton (3) can be and / or is coupled to ground (M) of the vehicle via a skeleton connection (13), wherein the intermediate layer capacity (C_Layer_12) and the skeleton capacity (C_Skeleton) form a capacitive voltage divider for a voltage applied to the first conductive layer (6), wherein a partial voltage can be tapped at the second conductive layer (8), characterized by an evaluation device (16), wherein the evaluation device (16) is designed to detect the partial voltage at the second conductive layer (8) and to assess the skeleton connection (13) as being in order or out of order based on the detected partial voltage.

2. The steering wheel arrangement (1) according to claim 1, characterized by a control device (15), the control device (15) being designed to bring, in a first phase (P1), the first conductive layer (6) and the second conductive layer (8) into a defined and / or common first voltage state and to decouple, in a second phase (P2), the second conductive layer (8) and to bring the first conductive layer (6) into a second voltage state, the evaluation device (16) being designed to measure the partial voltage in the second phase (P2).

3. The steering wheel arrangement (1) according to claim 2, characterized in that the first voltage state corresponds to ground (M) and the second voltage state corresponds to DC voltage (VDD).

4. The steering wheel arrangement (1) according to any one of the preceding claims, characterized in that an ambient capacity (C_Layer_1amb) is formed between the first conductive layer (6) and the steering wheel skeleton (3).

5. The steering wheel arrangement (1) according to any one of the preceding claims, characterized in that the evaluation device (16) and the control device (15) are formed as a joint data processing device (10).

6. The steering wheel arrangement (1) according to any one of the preceding claims, characterized in that the terminal (11) of the first conductive layer (6) is designed as a first GPIO and / or the second terminal (12) is designed at the second conductive layer (8) as a second GPIO.

7. The steering wheel arrangement (1) according to any one of the preceding claims, characterized in that the first layer (6) is designed as a sensor layer (7) for a HoD detection, and that the steering wheel arrangement (1) includes a hand detection device (17).

8. The steering wheel arrangement (1) according to claim 7, characterized in that the hand detection device (17) is formed in the joint data processing device (10).

9. The steering wheel arrangement (1) according to any one of the preceding claims, characterized by a third layer, wherein the third layer is arranged between the second conductive layer (8) and the steering wheel skeleton (3), wherein the skeleton capacity (C_Skeleton) is formed by a first single capacity between the second conductive layer (8) and the third conductive layer and a second single capacity between the third conductive layer and the steering wheel skeleton (3).

10. A vehicle, characterized by a steering wheel arrangement (1) according to any one of the preceding claims.

11. A method for verifying a skeleton connection (13) in a steering wheel arrangement (1) according to any one of the claims 1 to 9 and / or in a vehicle according to claim 10, wherein the partial voltage is detected at the second conductive layer (8) and the skeleton connection (13) is assessed as OK or not OK based on the detected partial voltage.

12. The method according to claim 11, characterized in that, in a first phase (P1), each of the first conductive layer (6) and the second conductive layer (8) is brought into a defined first voltage state and, in a second phase (P2), the second conductive layer (8) is decoupled and the first conductive layer (6) is brought into a second voltage state, wherein the second voltage state is designed to be different from the first voltage state, and then the partial voltage is measured in the second phase.