Steering wheel hand leaving detection method, program product, device, system and carrier

Abstract

The invention relates to the field of vehicle instruments, in particular to a method, a program product, a device, a system and a carrier for detecting hand separation of a steering wheel. A first excitation signal is input to an induction electrode, and a second excitation signal is input to an anti-phase electrode coupled with the induction electrode, and the phase of the second excitation signal is opposite to that of the first excitation signal; the first excitation signal on the induction electrode is obtained, when the driver leaves the hand, the steering wheel induction electrode and the anti-phase electrode cannot form coupling, the excitation signal on the steering wheel induction electrode cannot be counteracted by the anti-phase signal on the anti-phase electrode and cannot be weakened, and therefore it is judged that the driver leaves the hand. According to the method, a current mutual inductance principle is adopted, a backflow path formed by connecting a detection system to a steering wheel metal framework, a vehicle body, a driver seat metal framework and a driver is not depended on, the vehicle is prevented from being disassembled when the hand-leaving detection function is installed, and the hand-leaving detection function adopting a self-inductance scheme on an original vehicle is not interfered; and the compatibility is high.

Description

Technical Field

[0001] The present application relates to the field of vehicle equipment, and more particularly to a method, program product, device, system and vehicle for detecting hands-off-the-steering-wheel. Background Art

[0002] Hands On / Off Detection (HOD) technology is used to detect whether the driver is holding the steering wheel. With the development of autonomous driving technology, starting from level 3, the system needs to accurately identify whether the driver is holding the steering wheel to determine whether the vehicle is in active driving or autonomous driving. This technology is of great significance to ensure driving safety, comply with regulatory requirements, and improve driving experience.

[0003] The current mainstream method for detecting hands-off the steering wheel is a self-sensing detection scheme that uses the return path formed by "the detection system is connected to the metal frame of the steering wheel → the vehicle body → the metal frame of the driver's seat → and the driver himself" to determine whether the driver has taken his hands off the steering wheel. However, when the metal frame of the steering wheel and the vehicle body are insulated, or the metal frame of the driver's seat and the vehicle body are insulated, or when the detection system cannot be connected to the metal frame of the steering wheel in a non-destructive installed aftermarket HOD, or when any modification or addition causes the metal frame structure to be unable to cover this return path, this return path will be disconnected, rendering this mainstream method of detecting hands-off the steering wheel ineffective. Therefore, the solution of using the self-sensing detection principle to realize steering wheel hands-off detection in the prior art has certain limitations, a small scope of application, and low compatibility, and needs further improvement. Summary of the invention

[0004] In order to solve or at least partially solve the above technical problems, the present application provides a steering wheel hands-off detection method, comprising:

[0005] Inputting a first excitation signal to the sensing electrode;

[0006] Inputting a second excitation signal to an inverting electrode coupled to the sensing electrode, wherein the second excitation signal has a phase opposite to that of the first excitation signal;

[0007] Acquire a first excitation signal on the sensing electrode, and determine a hands-off state of the steering wheel according to a change in the first excitation signal disturbed by the second excitation signal;

[0008] The sensing electrode and the anti-phase electrode are arranged on the steering wheel or on an attachment near the steering wheel.

[0009] Optionally, the steering wheel hands-off detection method further includes:

[0010] The step of obtaining the second excitation signal is as follows: obtaining the first excitation signal, inverting and amplifying the first excitation signal, and obtaining a second excitation signal which is opposite in phase to the first excitation signal and is amplified.

[0011] Optionally, judging the hands-off state of the steering wheel according to the acquired change of the first excitation signal disturbed by the second excitation signal includes:

[0012] Based on detecting that the first excitation signal strength of the sensing electrode is lower than a preset value range, it is determined that the steering wheel is in a hands-on state,

[0013] Based on detecting that the strength of the first excitation signal of the sensing electrode is within a preset value range, it is determined that the steering wheel is in a hands-off state.

[0014] Optionally, the steering wheel hands-off detection method further includes:

[0015] Signal adjustment step: in response to an increase in the disturbance intensity of the environment on the first excitation signal, increasing the intensity of the second excitation signal; in response to a decrease in the disturbance intensity of the environment on the first excitation signal, reducing the intensity of the second excitation signal.

[0016] Optionally, the steering wheel hands-off detection method further includes:

[0017] A shielding signal is input to the shielding layer of at least part of the electronic component to which the excitation signal is input, and the phase of the shielding signal is consistent with the excitation signal in the electronic component wrapped by the shielding layer.

[0018] Optionally, the electronic component includes the sensing electrode and a cable connected to the sensing electrode; and / or,

[0019] The electronic component includes the counter electrode and a cable connected to the counter electrode.

[0020] Optionally, the step of inputting a shielding signal to a shielding layer of at least part of the electronic components to which the excitation signal is input comprises:

[0021] Acquire the excitation signal and input the excitation signal into the shielding layer as the shielding signal;

[0022] The excitation signal is compensated to maintain the strength of the excitation signal.

[0023] Optionally, the sensing electrode at least partially surrounds the anti-phase electrode; or,

[0024] The inverting electrode at least partially surrounds the sensing electrode.

[0025] The present application provides a computer program product, including a computer program or instructions, which implement the above-mentioned steering wheel hand-off detection method when executed by a processor.

[0026] The present application provides a steering wheel hands-off detection device, comprising:

[0027] A sensing electrode, disposed on the steering wheel or on an attachment near the steering wheel, for receiving a first excitation signal;

[0028] an anti-phase electrode, disposed on the steering wheel or on an attachment near the steering wheel, coupled with the sensing electrode, and used to receive a second excitation signal with a phase opposite to that of the first excitation signal;

[0029] The HOD detection unit is electrically connected to the sensing electrode and the inverting electrode, and is used to obtain the first excitation signal of the sensing electrode, and determine the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal.

[0030] Optionally, the steering wheel hands-off detection device further includes:

[0031] The first inverting amplifier unit is electrically connected to the HOD detection unit and the inverting electrode, and is used to invert and amplify the first excitation signal to obtain the second excitation signal which has an opposite phase to the first excitation signal and is amplified.

[0032] Optionally, the HOD detection unit is configured as:

[0033] Based on detecting that the intensity of the first excitation signal of the sensing electrode is lower than a preset value range, determining that the steering wheel is in a hands-on state;

[0034] Based on detecting that the strength of the first excitation signal of the sensing electrode is within a preset value range, it is determined that the steering wheel is in a hands-off state.

[0035] Optionally, the steering wheel hands-off detection device further includes:

[0036] The signal adjustment unit is connected to the path of the second excitation signal, and is used to adjust the intensity of the second excitation signal to increase or decrease the disturbance intensity of the first excitation signal.

[0037] Optionally, the steering wheel hands-off detection device further includes:

[0038] A first shielding layer is disposed between the sensing electrode and the steering wheel frame and receives a first shielding signal having a phase consistent with the first excitation signal to shield the sensing electrode;

[0039] The second shielding layer is arranged between the inverting electrode and the steering wheel frame, and receives a second shielding signal having a phase consistent with the second excitation signal to shield the inverting electrode.

[0040] Optionally, the steering wheel hands-off detection device further includes:

[0041] The signal holding unit is connected to the first shielding layer, receives the first excitation signal, performs compensation processing on the first excitation signal, and inputs the signal as the first shielding signal into the first shielding layer.

[0042] Optionally, the cable connected to the sensing electrodes has a third shielding layer, and the signal holding unit is connected to the third shielding layer to input the first shielding signal into the third shielding layer.

[0043] Optionally, the steering wheel hands-off detection device further includes:

[0044] The second inverting amplifying unit is connected to the second shielding layer, receives the first excitation signal, inverts and amplifies the first excitation signal, and inputs the first excitation signal as the second shielding signal to the second shielding layer.

[0045] Optionally, the cable connected to the inverting electrode has a fourth shielding layer, and the second inverting amplifying unit is connected to the fourth shielding layer to input the second shielding signal into the fourth shielding layer.

[0046] The present application provides a steering wheel hands-off detection system, comprising:

[0047] A first signal input module, used for inputting a first excitation signal to the sensing electrode;

[0048] A second signal input module, configured to input a second excitation signal having a phase opposite to that of the first excitation signal to an inverting electrode coupled to the sensing electrode;

[0049] The hands-off judgment module is used to obtain the first excitation signal of the sensing electrode, and judge the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal.

[0050] The sensing electrode and the anti-phase electrode are arranged on the steering wheel or on an attachment near the steering wheel.

[0051] The present application provides a carrier, on which is provided:

[0052] A computer program product as described above; or,

[0053] The hands-off steering wheel detection device as described above; or,

[0054] A hands-off steering wheel detection system as described above.

[0055] The present application arranges the sensing electrode and the reverse phase electrode on the steering wheel or on an attachment near the steering wheel, inputs a first excitation signal to the sensing electrode, inputs a second excitation signal to the reverse phase electrode coupled to the sensing electrode, wherein the second excitation signal is opposite in phase to the first excitation signal, and obtains the first excitation signal on the sensing electrode. When the driver takes his hands off the steering wheel, neither the steering wheel sensing electrode nor the steering wheel reverse phase electrode is held, and no coupling is formed. The excitation signal on the steering wheel sensing electrode will not be offset by the reverse phase signal on the reverse phase electrode, and will not be weakened, thereby judging that the driver has taken his hands off the steering wheel. This method is different from the traditional current self-inductance detection scheme. It adopts the principle of current mutual inductance and does not rely on the return path formed by "the detection system is connected to the metal frame of the steering wheel → the vehicle body → the metal frame of the driver's seat → and the driver himself". Therefore, it avoids the disassembly of the vehicle when the hand-off detection function is installed, and will not interfere with the hand-off detection function using the self-inductance scheme on the original vehicle. It has strong compatibility and a wide range of applications, and is particularly suitable for vehicles equipped with hand-off detection functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the implementation of the present application, the following is a brief introduction to the relevant drawings. It is understood that the drawings described below are only used to illustrate some implementations of the present application, and those skilled in the art can also obtain many other technical features and connection relationships not mentioned in this document based on these drawings.

[0057] Figure 1 A schematic diagram of a flow chart of an embodiment of the steering wheel hands-off detection solution of the present application;

[0058] Figure 2 A flowchart of another embodiment of the steering wheel hands-off detection solution of the present application;

[0059] Figure 3 This is a schematic diagram of the structural connection of the steering wheel hands-off detection device of this application;

[0060] Figure 4 is a waveform diagram of the first excitation signal of the sensing electrode in the hand-off state;

[0061] Figure 5 is a waveform diagram of the second excitation signal of the inverting electrode in the hand-off state;

[0062] Figure 6 This is a waveform diagram of the first excitation signal of the sensing electrode when the hand is not released.

[0063] Description of reference numerals:

[0064] 10. Sensing electrode; 20. Inverting electrode; 30. HOD detection unit; 31. Sensing terminal; 32. Excitation shielding terminal; 40. First inverting amplifying unit; 50. Signal holding unit; 60. Second inverting amplifying unit; 71. First shielding layer; 72. Second shielding layer; 73. Third shielding layer; 74. Fourth shielding layer. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0066] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0067] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0068] The technical solutions in the embodiments of the present application will be described in detail below in conjunction with the drawings in the embodiments of the present application.

[0069] Example 1

[0070] In order to realize the steering wheel hand-off detection function, the present embodiment provides a steering wheel hand-off detection method. Before the implementation steps of the method of the present embodiment, the present embodiment sets a sensing electrode 10 and a counter electrode 20 on the steering wheel. The sensing electrode 10 and the counter electrode 20 are coupled so that the electrical signals of the two can be coupled or interfered through external conditions.

[0071] like Figure 1 As shown, the method comprises the following steps:

[0072] Step 1: inputting a first excitation signal to the sensing electrode 10;

[0073] Step 2: inputting a second excitation signal to the inverting electrode 20 coupled to the sensed electrode 10, wherein the second excitation signal has a phase opposite to that of the first excitation signal;

[0074] Step 3: Acquire the first excitation signal on the sensing electrode 10, and determine the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal.

[0075] In this embodiment, since the steering wheel has the sensing electrode 10 and the anti-phase electrode 20, the sensing electrode 10 and the anti-phase electrode 20 are coupled to each other so that the driver's hand can hold the sensing electrode 10 and the anti-phase electrode 20 at the same time when grasping the steering wheel. The sensing electrode 10 carries a first excitation signal, and the anti-phase electrode 20 carries a second excitation signal. It is worth mentioning that the phase of the second excitation signal is opposite to that of the first excitation signal. When the driver's hand holds the sensing electrode 10 and the anti-phase electrode 20, the first excitation signal is coupled with the second excitation signal, and the second excitation signal will correspondingly offset a part of the first excitation signal, so that the first excitation signal is weakened. Therefore, by detecting whether the first excitation signal on the sensing electrode 10 is weakened, the hand-off state of the steering wheel can be detected, such as Figure 4 , Figure 5 , Figure 6 As shown in the figure, the horizontal axis t is time, and the vertical axis f is the amplitude or intensity of the excitation signal.

[0076] Specifically, in one embodiment, the sensing electrode 10 is disposed on the upper surface of the steering wheel, and the anti-phase electrode 20 is disposed on the lower surface of the steering wheel. The upper surface of the steering wheel may be the side of the steering wheel facing the face of the person, and the lower surface of the steering wheel may be the side of the steering wheel facing the vehicle computer. When the driver holds the steering wheel, both the sensing electrode 10 and the anti-phase electrode 20 are held by the hand. At this time, the first excitation signal on the sensing electrode 10 is coupled with the second excitation signal on the anti-phase electrode 20. Since the second excitation signal is in opposite phase to the first excitation signal, the first excitation signal will be offset by the second excitation signal and then weakened. At this time, the first excitation signal is in a significantly weakened state, such as Figure 6 As shown, the intensity of the first excitation signal is significantly smaller than Figure 4Therefore, when it is detected that the first excitation signal on the sensing electrode 10 reaches the expected weakening condition, it is determined that the steering wheel is in the state of not leaving the hand. When the driver's hand is off the steering wheel, the sensing electrode 10 and the inverting electrode 20 are not held by the hand, and the first excitation signal on the sensing electrode 10 and the second excitation signal on the inverting electrode 20 will not be coupled. At this time, the first excitation signal on the sensing electrode 10 will not be affected by the coupling of the second excitation signal, such as Figure 4 As shown, the intensity of the first excitation signal is significantly greater than Figure 6 Therefore, when it is detected that the first excitation signal on the sensing electrode 10 is not significantly weakened or is at an expected strength value, it is determined that the steering wheel is in a hands-off state.

[0077] This method uses the principle of current mutual induction. Unlike traditional current self-induction detection schemes, the method of the present application does not rely on the return path formed by "the detection system is connected to the metal frame of the steering wheel → the vehicle body → the metal frame of the driver's seat → and the driver himself". Therefore, it avoids the disassembly of the vehicle when installing the hands-off detection function, and will not interfere with the hands-off detection function of the original vehicle that uses a self-induction scheme. It has strong compatibility and a wide range of applications, and is particularly suitable for vehicles equipped with hands-off detection functions.

[0078] Step 1 and step 2 mentioned in this embodiment may be performed sequentially or simultaneously. For example, while a first excitation signal is input to the sensing electrode 10, a second excitation signal is input to the inverting electrode 20. When the first excitation signal and the second excitation signal are in place, the first excitation signal on the sensing electrode is detected through step 3, that is, the steering wheel hand-off detection method in this embodiment, and the execution steps are not particularly limited.

[0079] In this embodiment, a HOD detection unit 30 may be provided, and the HOD detection unit 30 is electrically connected to the sensing electrode 10 and the inverting electrode 20, respectively, and is used to output a first excitation signal to the sensing electrode 10 and a second excitation signal to the inverting electrode 20. The HOD detection unit 30 can not only output a signal, but also detect the first excitation signal on the sensing electrode 10 through signal feedback, and generate a corresponding feedback signal according to whether the first excitation signal is weakened, so as to realize the hand-off state judgment of the steering wheel.

[0080] In one embodiment, the HOD detection unit 30 determines the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal, and the specific determination method is as follows:

[0081] Based on detecting that the first excitation signal strength of the sensing electrode 10 is lower than a preset value range, determining that the steering wheel is in a hands-on state;

[0082] Based on detecting that the strength of the first excitation signal of the sensing electrode 10 is within a preset value range, it is determined that the steering wheel is in a hands-off state.

[0083] The preset value range in this embodiment is determined based on the first excitation signal when it is not coupled and weakened by the second excitation signal. When the first excitation signal is not coupled and weakened by the second excitation signal, it is at a first intensity value, and when the first excitation signal is coupled and weakened by the second excitation signal, it is at a second intensity value, and the second intensity value is less than the first intensity value. An appropriate threshold range can be taken between the second intensity value and the first intensity value as the preset value range of this embodiment. The preset value range can be calibrated and set according to the required sensitivity of the adjustment detection.

[0084] It is worth mentioning that, since the signal itself is unstable during transmission, the first excitation signal itself also has certain fluctuations, so the amplitude of the first excitation signal is not a fixed value, so this embodiment does not mean that as long as the amplitude of the first excitation signal is weakened, it is judged that the hand has not left the hand. Based on this, according to the characteristics of the first excitation signal itself and the degree of influence of the coupling of the second excitation signal, the preset value range is reasonably designed, which can effectively avoid the situation where the first excitation signal is detected to be weakened and misjudged.

[0085] The sensing electrode 10 and the inverting electrode 20 of the present embodiment are not limited to being arranged on the steering wheel body. The sensing electrode 10 and the inverting electrode 20 may be a part of the steering wheel body, or may be a device attached to the steering wheel or an attachment near the steering wheel, such as a steering wheel cover. The sensing electrode 10 and the inverting electrode 20 as described above are arranged on the steering wheel cover, and the steering wheel cover is installed on the steering wheel. At the same time, the method can be implemented to achieve the hand-off detection function.

[0086] Example 2

[0087] This embodiment provides a method for detecting hands-off steering wheel. This method is based on the above-mentioned embodiment 1 and further improves the acquisition of the second excitation signal.

[0088] The method steps of this embodiment also include: obtaining a second excitation signal step, that is, obtaining the first excitation signal, performing inversion processing on the first excitation signal, and obtaining a second excitation signal with a phase opposite to the first excitation signal.

[0089] In this embodiment, no additional excitation signal is provided, but a signal identical to the first excitation signal of the sensing electrode 10 is obtained, and the first excitation signal is converted into a second excitation signal with an opposite phase and output to the anti-phase electrode 20 .

[0090] like Figure 2As shown, in one embodiment, the step of obtaining the second excitation signal includes: obtaining the first excitation signal, inverting and amplifying the first excitation signal, and obtaining a second excitation signal with a phase opposite to the first excitation signal and an amplified signal.

[0091] In this embodiment, the second excitation signal may be amplified or not. After amplification, the first excitation signal is weakened more obviously when the hand is not released, which is more conducive to determining that the hand is not released.

[0092] In one embodiment, Figure 3 As shown, the HOD detection unit 30 has a sensing terminal 31 and an excitation shielding terminal 32. The sensing terminal 31 is connected to the sensing electrode 10 through a coaxial cable to input a first excitation signal to the sensing electrode 10. The excitation shielding terminal 32 is connected to the inverting electrode 20 through a coaxial cable, and a first inverting amplifier unit 40 is connected between the excitation shielding terminal 32 and the inverting electrode 20. The excitation shielding terminal 32 outputs the first excitation signal to the first inverting amplifier unit 40. The first inverting amplifier unit 40 inverts and amplifies the first excitation signal to obtain a second excitation signal with a phase opposite to the first excitation signal and amplified signal, and the second excitation signal is input to the inverting electrode 20 through the cable.

[0093] In this way, the sensing electrode 10 and the inverting electrode 20 can be connected to the same signal source, which can reduce power consumption and save energy accordingly. Moreover, the excitation shielding terminal 32 of the HOD detection unit 30 is placed in the first excitation signal to be converted into the second excitation signal for use, which can also meet the low voltage requirement and reduce the withstand voltage requirement of the entire detection system. Moreover, compared with the traditional multiple signal sources, this method also has the advantage of low radiation.

[0094] The first inverting amplifier unit 40 in this embodiment includes a circuit or electronic component with inverting and amplifying functions, as long as it can achieve phase inversion and signal amplification of the electrical signal.

[0095] Of course, this embodiment is not limited to converting the first excitation signal into the second excitation signal by inverting and amplifying, but can also connect other signals different from the first excitation signal, such as a third excitation signal, etc. If the third excitation signal has the same phase as the second excitation signal, the third excitation signal can be amplified or reduced. If the third excitation signal has an opposite phase to the second excitation signal, the third excitation signal is correspondingly inverted and amplified or reduced.

[0096] In this embodiment, the intensity of the second excitation signal may be the same as or different from that of the first excitation signal.

[0097] In the method for detecting hands-off steering wheel in this embodiment, the second excitation signal may also be adjusted in magnitude to change the intensity of disturbance of the first excitation signal by the second excitation signal.

[0098] Specifically, the signal adjustment step includes: in response to an increase in the disturbance intensity of the environment on the first excitation signal, increasing the intensity of the second excitation signal; in response to a decrease in the disturbance intensity of the environment on the first excitation signal, reducing the intensity of the second excitation signal.

[0099] That is to say, when the external environment has little effect on the detection of the first excitation signal and the first excitation signal on the sensing electrode 10 is easy to be detected, the strength of the second excitation signal can be appropriately reduced, which can relatively reduce the disturbance of the second excitation signal to the first excitation signal and reduce power consumption.

[0100] When the external environment affects the first excitation signal and the first excitation signal on the sensing electrode 10 is not easy to be detected, it is necessary to increase the strength of the second excitation signal to increase the disturbance intensity of the second excitation signal on the first excitation signal. In this way, the weakening of the first excitation signal is more obvious, which is conducive to improving the accuracy of hand-off detection.

[0101] For example, in a high-noise environment or an environment with large temperature changes, the ability to distinguish a hand from being removed can be greatly improved, thereby improving the detection performance.

[0102] Example 3

[0103] The present embodiment provides a method for detecting hands-off the steering wheel, in which the above-mentioned embodiment is further optimized through a shielding step, which can reduce interference and improve the accuracy of hands-off detection. For example, when there are components in the steering wheel such as a heating device, a steering wheel hub, etc. that may interfere with the electrodes, it is necessary to add a shielding design.

[0104] The method of this embodiment also includes a signal shielding step:

[0105] A shielding signal is input to the shielding layer of at least part of the components to which the excitation signal is input, and the phase of the shielding signal is consistent with the excitation signal in the components wrapped by the shielding layer.

[0106] In this embodiment, a shielding signal is input into the shielding layer of the electronic component having the above-mentioned first excitation signal or the second excitation signal, and the phase of the shielding signal is consistent with the excitation signal in the electronic component wrapped by the shielding layer, so as to form a positive excitation shielding for the first excitation signal or the second excitation signal, reduce the interference of the first excitation signal or the second excitation signal by the outside world, thereby ensuring the strength of the first excitation signal and the second excitation signal, ensuring the accuracy of the detection data, and improving the accuracy of hand-off detection.

[0107] Preferably, the signal shielding step can be performed simultaneously with the above steps 1 and 2.

[0108] In one embodiment, the electronic component includes a sensing electrode 10 and a cable connected to the sensing electrode 10 ; and also includes a counter electrode 20 and a cable connected to the counter electrode 20 .

[0109] like Figure 3 As shown, in one embodiment, since the sensing electrode 10 and the counter electrode 20 of the steering wheel are arranged to be distributed on the upper and lower surfaces of the steering wheel, it is preferred to arrange the sensing electrode 10 toward the palm of the hand during implementation, and the two themselves will be coupled by the metal skeleton or metal wiring inside the steering wheel, so a first shielding layer 71 is arranged below the steering wheel sensing electrode 10. In the signal shielding step of this embodiment, an excitation signal having the same magnitude and phase as the first excitation signal of the sensing electrode 10 is input to the first shielding layer 71, and the steering wheel sensing electrode 10 is excited and shielded. Similarly, a second shielding layer 72 is arranged below the counter electrode 20 of the steering wheel, and an excitation signal having the same magnitude and phase as the second excitation signal of the counter electrode 20 is input to the second shielding layer 72, and the steering wheel counter electrode 20 is excited and shielded.

[0110] In one embodiment, the first shielding layer 71 and the second shielding layer 72 are metal shielding layers.

[0111] Furthermore, in an embodiment of the method, an excitation signal may be acquired and input into the shielding layer as a shielding signal, and the excitation signal may be compensated to maintain the strength of the excitation signal.

[0112] like Figure 3 As shown, the present embodiment is further provided with a signal holding unit 50, the input end of the signal holding unit 50 is connected to the excitation shielding terminal 32 for receiving the first excitation signal, and the output end of the signal holding unit 50 is connected to the first shielding layer 71. The signal holding unit 50 performs compensation processing on the first excitation signal of the excitation shielding terminal 32 and then inputs the first shielding layer 71. In this way, the first shielding layer 71 and the sensing electrode 10 maintain the excitation signal of the same magnitude and phase, which can reduce the coupling from the metal skeleton or metal wiring inside the steering wheel, and improve the shielding effect.

[0113] The signal holding unit 50 is used to keep the output excitation signal unchanged, so that the first excitation signal received by the first shielding layer 71 is consistent with the first excitation signal of the sensing electrode 10; of course, in some embodiments, the output excitation signal can also be adjusted to be consistent with the first excitation signal.

[0114] In one embodiment, the signal holding unit 50 may be a follower or other device.

[0115] like Figure 3 As shown, the present embodiment is further provided with a second inverting amplifier unit 60, the input end of the second inverting amplifier unit 60 is connected to the excitation shielding terminal 32 for receiving the first excitation signal, and the output end of the second inverting amplifier unit 60 is connected to the second shielding layer 72. The second inverting amplifier unit 60 is the same as the first inverting amplifier unit 40, and converts the first excitation signal into a second excitation signal after inverting and amplifying the first excitation signal, and inputs the second excitation signal into the second shielding layer 72. Similarly, the second shielding layer 72 maintains the excitation signal of the same magnitude and phase as the inverting electrode 20, which can reduce the coupling from the metal skeleton or metal wiring inside the steering wheel, and improve the shielding effect.

[0116] In this embodiment, the first excitation signal and the second excitation signal are transmitted through a cable. When the cable transmits the first excitation signal and the second excitation signal, coupling may occur, resulting in signal weakening. Therefore, in this embodiment, Figure 3 As shown, the cable connected to the sensing electrode 10 has a third shielding layer 73, and the cable connected to the reverse electrode 20 has a fourth shielding layer 74. The signal holding unit 50 is electrically connected to the third shielding layer 73, and the third shielding layer 73 has a shielding signal identical to the first excitation signal, and the coaxial cable for transmitting the first excitation signal to the steering wheel is excited and shielded; the second inverting amplification unit 60 is electrically connected to the fourth shielding layer 74, and the fourth shielding layer 74 has a shielding signal identical to the second excitation signal, and the coaxial cable for transmitting the second excitation signal to the steering wheel is excited and shielded.

[0117] In the above embodiment, the sensing electrodes and the inverting electrodes are arranged using metal wires. When the inverting electrodes are arranged in multiple partitions, in order to reduce coupling interference between the partitions, the sensing electrodes are arranged to at least partially surround the inverting electrodes.

[0118] In one embodiment, the inverting electrode is arranged in a circuitous manner on the steering wheel or on an attachment near the steering wheel, and the sensing electrode is arranged around the outside of the inverting electrode to surround the inverting electrode. The area surrounded by the sensing electrode forms a detection area, and there are at least a plurality of such detection areas on the steering wheel or on an attachment near the steering wheel. When there are multiple detection areas and inverting electrodes, the sensing electrode can be arranged around the inverting electrode of each detection area respectively, or around the inverting electrodes of multiple detection areas.

[0119] In one embodiment, the anti-phase electrode may also be arranged to at least partially surround the sensing electrode in the same manner as described above, which will not be described in detail herein.

[0120] Example 4

[0121] This embodiment provides a computer program product, including a computer program or instructions. When the computer program or instructions are executed by a processor, the above-mentioned steering wheel hand-off detection method is implemented. Therefore, the computer program product provided by this embodiment also has all the advantages described above.

[0122] Example 5

[0123] This embodiment provides a steering wheel hands-off detection device, such as Figure 3 As shown, the device includes a sensing electrode 10, an anti-phase electrode 20 and a HOD detection unit 30. The sensing electrode 10 and the anti-phase electrode 20 are respectively arranged on the steering wheel or on an attachment near the steering wheel, the sensing electrode 10 is used to receive a first excitation signal, and the anti-phase electrode 20 is coupled to the sensing electrode 10 to receive a second excitation signal with a phase opposite to the first excitation signal.

[0124] The HOD detection unit 30 is electrically connected to the sensing electrode 10 and the inverting electrode 20, and is used to obtain the first excitation signal of the sensing electrode 10, and determine the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal.

[0125] In this embodiment, a first excitation signal is input to the sensing electrode 10, and a second excitation signal is input to the inverting electrode 20 coupled to the sensing electrode 10, wherein the second excitation signal is opposite in phase to the first excitation signal, and the first excitation signal on the sensing electrode 10 is obtained. When the driver takes his hands off the steering wheel, neither the steering wheel sensing electrode 10 nor the steering wheel inverting electrode 20 is held, and no coupling is formed. The excitation signal on the steering wheel sensing electrode 10 will not be offset by the inverting signal on the inverting electrode 20, and will not be significantly weakened, thereby judging that the driver has taken his hands off. This method is different from the traditional current self-inductance detection scheme. It adopts the principle of mutual inductance of capacitance and does not rely on the return path formed by "the detection system is connected to the metal frame of the steering wheel → the vehicle body → the metal frame of the driver's seat → and the driver himself". Therefore, it avoids the disassembly of the vehicle when installing the hand-off detection function, and will not interfere with the hand-off detection function using the self-inductance scheme on the original vehicle, and has strong compatibility.

[0126] like Figure 3 As shown, in one embodiment, the device has a first inverting amplifier unit 40, which is electrically connected to the HOD detection unit 30 and the inverting electrode 20, and is used to invert and amplify the first excitation signal to obtain the second excitation signal which has an opposite phase to the first excitation signal and is amplified.

[0127] Specifically, the HOD detection unit 30 has a sensing terminal 31 and an excitation shielding terminal 32. The sensing terminal 31 is connected to the sensing electrode 10 through a coaxial cable to input a first excitation signal to the sensing electrode 10. The excitation shielding terminal 32 is connected to the inverting electrode 20 through a coaxial cable. The first inverting amplifier unit 40 is connected between the excitation shielding terminal 32 and the inverting electrode 20. The excitation shielding terminal 32 outputs the first excitation signal to the first inverting amplifier unit 40. The first inverting amplifier unit 40 inverts and amplifies the first excitation signal to obtain a second excitation signal with a phase opposite to the first excitation signal and amplified signal, and inputs the second excitation signal to the inverting electrode 20 through the cable.

[0128] The sensing electrode 10 and the inverting electrode 20 of this embodiment can be connected to the same signal source, and the excitation signal is invertedly amplified by the first inverting amplifier unit 40 to obtain an inverted excitation signal, which has the advantages of low power consumption, low withstand voltage requirement, and low radiation. For details, please refer to the description in Example 2, which will not be repeated here.

[0129] In this embodiment, the HOD detection unit 30 determines that the steering wheel is in a hands-on state based on detecting that the first excitation signal strength of the sensing electrode 10 is lower than a preset value range, and determines that the steering wheel is in a hands-off state based on detecting that the first excitation signal strength of the sensing electrode 10 is within a preset value range.

[0130] The preset value range in this embodiment is determined based on the first excitation signal when it is not coupled and weakened by the second excitation signal. When the first excitation signal is not coupled and weakened by the second excitation signal, it is at a first intensity value, and when the first excitation signal is coupled and weakened by the second excitation signal, it is at a second intensity value, and the second intensity value is less than the first intensity value. An appropriate threshold range can be taken between the second intensity value and the first intensity value as the preset value range of this embodiment. The preset value range can be calibrated and set according to the required sensitivity of the adjustment detection.

[0131] The HOD detection unit 30 may be any chip with an HOD detection function. The HOD detection unit 30 may send a signal to an external feedback mechanism so that when it is determined that the hands are off the steering wheel, the external feedback mechanism may make a corresponding reminder to ensure driving safety.

[0132] In one embodiment, the equipment has a signal adjustment unit connected to the transmission path of the second excitation signal and used to adjust the intensity of the second excitation signal to increase or decrease the disturbance intensity of the first excitation signal.

[0133] When the external environment has little effect on the detection of the first excitation signal and the first excitation signal on the sensing electrode 10 is easy to be detected, the signal adjustment unit can appropriately reduce the strength of the second excitation signal, thereby relatively reducing the disturbance of the second excitation signal to the first excitation signal and reducing power consumption.

[0134] When the external environment affects the first excitation signal and the first excitation signal on the sensing electrode 10 is not easy to be detected, the signal adjustment unit can be used to increase the intensity of the second excitation signal so that the disturbance intensity of the second excitation signal on the first excitation signal increases. In this way, the weakening of the first excitation signal is more obvious, which is beneficial to improving the accuracy of hand-off detection.

[0135] like Figure 3 As shown, in one embodiment, the device further comprises a first shielding layer 71 and a second shielding layer 72, wherein the first shielding layer 71 is disposed between the sensing electrode 10 and the steering wheel frame, and receives a first shielding signal having a phase consistent with the first excitation signal, so as to shield the sensing electrode 10. The second shielding layer 72 is disposed between the anti-phase electrode 20 and the steering wheel frame, and receives a second shielding signal having a phase consistent with the second excitation signal, so as to shield the anti-phase electrode 20.

[0136] The input end of the signal holding unit 50 is connected to the excitation shielding terminal 32 for receiving the first excitation signal, and the output end of the signal holding unit 50 is connected to the first shielding layer 71. The signal holding unit 50 performs compensation processing on the first excitation signal of the excitation shielding terminal 32 and then inputs the first shielding layer 71. In this way, the first shielding layer 71 and the sensing electrode 10 maintain the excitation signal of the same magnitude and phase, which can reduce the coupling from the metal frame or metal wiring inside the steering wheel and improve the shielding effect.

[0137] The input end of the second inverting amplifier unit 60 is connected to the excitation shielding terminal 32 for receiving the first excitation signal, and the output end of the second inverting amplifier unit 60 is connected to the second shielding layer 72. The second inverting amplifier unit 60 is the same as the first inverting amplifier unit 40, and converts the first excitation signal into a second excitation signal after inverting and amplifying, and inputs the second excitation signal into the second shielding layer 72 through a cable. Similarly, the second shielding layer 72 maintains the excitation signal of the same magnitude and phase as the inverting electrode 20, which can reduce the coupling from the metal skeleton or metal wiring inside the steering wheel, thereby improving the shielding effect.

[0138] Furthermore, in one embodiment, the shielding layer further includes a third shielding layer 73 of the cable connected to the sensing electrode 10 , and a fourth shielding layer 74 of the cable connected to the counter electrode 20 .

[0139] like Figure 3As shown, the output end of the signal holding unit 50 is connected to the third shielding layer 73, the third shielding layer 73 has a shielding signal that is the same as the first excitation signal, and the coaxial cable that transmits the first excitation signal to the steering wheel is excited and shielded; the output end of the second inverting amplification unit 60 is connected to the fourth shielding layer 74, the fourth shielding layer 74 has a shielding signal that is the same as the second excitation signal, and the coaxial cable that transmits the second excitation signal to the steering wheel is excited and shielded.

[0140] Example 6

[0141] This embodiment provides a steering wheel hands-off detection system, which includes a first signal input module, a second signal input module, and a hands-off judgment module.

[0142] Among them, the first signal input module is used to input a first excitation signal to the sensing electrode 10, and the second signal input module is used to input a second excitation signal with a phase opposite to the first excitation signal to the inverting electrode 20 coupled to the sensing electrode 10; the hand-off judgment module is used to obtain the first excitation signal of the sensing electrode 10, and judge the hand-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal.

[0143] The sensing electrode 10 and the anti-phase electrode 20 are arranged on the steering wheel or on an attachment near the steering wheel, and the sensing electrode 10 and the anti-phase electrode 20 are coupled. When the driver holds the steering wheel, both the sensing electrode 10 and the anti-phase electrode 20 are held by the hand. At this time, the first excitation signal on the sensing electrode 10 is coupled with the second excitation signal on the anti-phase electrode 20. Since the second excitation signal is opposite to the first excitation signal in phase, the first excitation signal will be offset by the second excitation signal and then significantly weakened. At this time, the first excitation signal is in a significantly weakened state. Therefore, when it is detected that the first excitation signal on the sensing electrode 10 reaches the expected weakening state, it is determined that the steering wheel is in a state where the driver does not leave the hand.

[0144] When the driver's hands are off the steering wheel, the sensing electrode 10 and the inverting electrode 20 are not held by the hands, and the first excitation signal on the sensing electrode 10 and the second excitation signal on the inverting electrode 20 will not be coupled. At this time, the first excitation signal on the sensing electrode 10 will not be significantly weakened by the coupling of the second excitation signal. Therefore, when it is detected that the first excitation signal on the sensing electrode 10 has not been weakened as expected, it is determined that the steering wheel is in a hands-off state.

[0145] The system can be installed on the vehicle steering wheel, or set on an attachment near the steering wheel, such as inside the steering wheel cover. The system can realize vehicle hand-off detection, does not rely on disassembly of the vehicle body, is applicable to various vehicle models, and has strong compatibility.

[0146] Example 7

[0147] This embodiment provides a vehicle, on which is disposed a computer program product as described in Embodiment 4; or, the vehicle is disposed with the steering wheel hands-off detection device as described in Embodiment 5; or, the vehicle is disposed with the steering wheel hands-off detection system as described in Embodiment 6. Since the vehicle includes the products of the above embodiments, the vehicle also has all the advantages of the products in the above embodiments.

[0148] In addition, it is worth mentioning that vehicles include not only cars, but also various other means of transportation, such as cars, aircraft, ships, etc. In addition, the vehicles mentioned in this application also include some simulation equipment that simulates traditional means of transportation and carries people, such as operation experience equipment that simulates the operation experience of racing, airplanes or ships, teaching equipment, VR game equipment, etc. As long as it is a device that carries people and is prone to relatively large vibrations, it can meet the definition of the vehicle of this application.

[0149] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0150] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0151] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting hands-off steering wheel, characterized in that: include: Inputting a first excitation signal to the sensing electrode (10); Inputting a second excitation signal to an inverting electrode (20) coupled to the sensing electrode (10), wherein the second excitation signal has a phase opposite to that of the first excitation signal; Acquiring a first excitation signal on the sensing electrode (10), and judging the hands-off state of the steering wheel according to a change in the first excitation signal disturbed by the second excitation signal; The sensing electrode (10) and the reverse electrode (20) are arranged on a steering wheel or on an attachment near the steering wheel.

2. The method for detecting hands-off steering wheel according to claim 1, characterized in that: Also includes: The step of obtaining the second excitation signal is as follows: obtaining the first excitation signal, inverting and amplifying the first excitation signal, and obtaining a second excitation signal which is opposite in phase to the first excitation signal and is amplified.

3. The method for detecting hands-off steering wheel according to claim 1, characterized in that: The step of determining the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal comprises: Based on detecting that the intensity of the first excitation signal of the sensing electrode (10) is lower than a preset value range, it is determined that the steering wheel is in a hands-on state; Based on detecting that the first excitation signal strength of the sensing electrode (10) is within a preset value range, it is determined that the steering wheel is in a hands-off state.

4. The method for detecting hands-off steering wheel according to claim 1, characterized in that: Also includes: Signal adjustment step: in response to an increase in the disturbance intensity of the environment on the first excitation signal, increasing the intensity of the second excitation signal; In response to a reduction in the intensity of disturbance of the first excitation signal by the environment, the intensity of the second excitation signal is reduced.

5. The method for detecting hands-off steering wheel according to any one of claims 1 to 4, characterized in that: Also includes: A shielding signal is input to the shielding layer of at least part of the electronic component to which the excitation signal is input, and the phase of the shielding signal is consistent with the excitation signal in the electronic component wrapped by the shielding layer.

6. The method for detecting hands-off steering wheel according to claim 5, characterized in that: The electronic component comprises the sensing electrode (10) and a cable connected to the sensing electrode (10); and / or, The electronic component comprises the counter electrode (20) and a cable connected to the counter electrode (20).

7. The method for detecting hands-off steering wheel according to claim 5, characterized in that: The step of inputting a shielding signal to the shielding layer of at least part of the electronic components to which the excitation signal is input comprises: Acquire the excitation signal and input the excitation signal into the shielding layer as the shielding signal; The excitation signal is compensated to maintain the strength of the excitation signal.

8. The method for detecting hands-off steering wheel according to claim 1, characterized in that: The sensing electrode (10) at least partially surrounds the anti-phase electrode (20); or, The inverting electrode (20) at least partially surrounds the sensing electrode (10).

9. A computer program product, comprising a computer program or instructions, characterized in that: When the computer program or instruction is executed by a processor, the method for detecting hands-off steering wheel as claimed in any one of claims 1 to 8 is implemented.

10. A steering wheel hands-off detection device, characterized in that: include: A sensing electrode (10) is arranged on the steering wheel or on an attachment near the steering wheel, and is used to receive a first excitation signal; an anti-phase electrode (20), arranged on the steering wheel or on an attachment near the steering wheel, coupled to the sensing electrode (10), and used to receive a second excitation signal having a phase opposite to that of the first excitation signal; The HOD detection unit (30) is electrically connected to the sensing electrode (10) and the inverting electrode (20), and is used to obtain the first excitation signal of the sensing electrode (10), and to determine the hands-off state of the steering wheel according to a change in the first excitation signal disturbed by the second excitation signal.

11. The device for detecting hands-off the steering wheel according to claim 10, characterized in that: Also includes: The first inverting amplifier unit (40) is electrically connected to the HOD detection unit (30) and the inverting electrode (20), and is used to invert and amplify the first excitation signal to obtain the second excitation signal which has an opposite phase to the first excitation signal and is amplified.

12. The device for detecting hands-off the steering wheel according to claim 10, characterized in that: The HOD detection unit (30) is configured as follows: Based on detecting that the intensity of the first excitation signal of the sensing electrode (10) is lower than a preset value range, determining that the steering wheel is in a hands-on state; Based on detecting that the first excitation signal strength of the sensing electrode (10) is within a preset value range, it is determined that the steering wheel is in a hands-off state.

13. The device for detecting hands-off steering wheel according to claim 10, characterized in that: Also includes: The signal adjustment unit is connected to the path of the second excitation signal, and is used to adjust the intensity of the second excitation signal to increase or decrease the disturbance intensity of the first excitation signal.

14. The device for detecting hands-off steering wheel according to claim 10, characterized in that: Also includes: A first shielding layer (71) is arranged between the sensing electrode (10) and the steering wheel frame and receives a first shielding signal having a phase consistent with the first excitation signal to shield the sensing electrode (10); The second shielding layer (72) is arranged between the inverting electrode (20) and the steering wheel frame, and receives a second shielding signal having a phase consistent with the second excitation signal, so as to shield the inverting electrode (20).

15. The device for detecting hands-off the steering wheel according to claim 14, characterized in that: Also includes: The signal holding unit (50) is connected to the first shielding layer (71), receives the first excitation signal, performs compensation processing on the first excitation signal, and inputs the signal as the first shielding signal into the first shielding layer (71).

16. The device for detecting hands-off steering wheel according to claim 15, characterized in that: The cable connected to the sensing electrode (10) has a third shielding layer (73), and the signal holding unit (50) is connected to the third shielding layer (73) to input the first shielding signal into the third shielding layer (73).

17. The device for detecting hands-off steering wheel according to claim 14, characterized in that: Also includes: The second inverting amplifier unit (60) is connected to the second shielding layer (72), receives the first excitation signal, inverts and amplifies the first excitation signal, and inputs the first excitation signal as the second shielding signal to the second shielding layer (72).

18. The device for detecting hands-off the steering wheel according to claim 17, characterized in that: The cable connected to the inverting electrode (20) has a fourth shielding layer (74), and the second inverting amplifying unit (60) is connected to the fourth shielding layer (74) to input the second shielding signal into the fourth shielding layer (74).

19. A steering wheel hands-off detection system, characterized in that: include: A first signal input module, used for inputting a first excitation signal to the sensing electrode (10); A second signal input module, used for inputting a second excitation signal having a phase opposite to that of the first excitation signal to an inverting electrode (20) coupled to the sensing electrode (10); The hands-off judgment module is used to obtain the first excitation signal of the sensing electrode (10), and judge the hands-off state of the steering wheel according to the change of the first excitation signal disturbed by the second excitation signal. The sensing electrode (10) and the reverse electrode (20) are arranged on a steering wheel or on an attachment near the steering wheel.

20. A carrier, characterized in that: It is equipped with: A computer program product as claimed in claim 9; or The hands-off-steering-wheel detection device according to any one of claims 10 to 18; or The hands-off-steering-wheel detection system as claimed in claim 19.

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