Steering control device, touch information hands-off detection method, system, vehicle

Abstract

This invention discloses a steering control device, a method for detecting touch information leaving the hand, a system, and a vehicle. The steering control device has a first conductive layer and a second conductive layer that are mutually insulated. The first conductive layer is embedded within the steering control device, and the second conductive layer is configured to form a conductive relationship with the hand through direct or indirect contact. The method for detecting touch information leaving the hand based on the steering control device includes the steps of: applying an excitation signal to the first conductive layer; acquiring a first electrical signal generated by the first conductive layer and a second electrical signal generated by the second conductive layer; and determining the contact state between the hand and the steering control device based on the change in the relationship between the first and second electrical signals. This invention can detect the contact state between the hand and the steering control device and has higher sensitivity compared to capacitive sensor measurement technology.

Description

Technical Field

[0001] This invention relates to a direction control device, a method and system for detecting touch information leaving the hand, and a vehicle. Background Technology

[0002] Steering wheels are widely used in vehicle steering control. Detecting whether the driver's hands are off the steering wheel is an important research direction. Taking automobiles as an example, when driver assistance is activated, it is necessary to monitor whether the driver's hands are on the steering wheel.

[0003] Currently, capacitive sensor measurement technology is a commonly used steering wheel hands-off detection technology. This technology uses a thin metal film as electrodes, which are placed under the leather of the steering wheel. The hand does not directly contact the electrodes. Force is applied to the steering wheel by the hand, causing a change in the capacitance value of the electrodes relative to ground. This change in capacitance value is then analyzed to determine the contact state between the hand and the steering wheel. Because the electrodes must be encased under the interior trim, often three fingers are needed to contact the steering wheel simultaneously to detect the hand's presence. In other words, the sensitivity of capacitive sensor measurement technology is relatively poor. This invention aims to provide a hands-off detection method applicable to steering wheels and other steering control devices. This method can detect the contact state between the hand and the steering control device and offers higher sensitivity compared to capacitive sensor measurement technology. Summary of the Invention

[0004] To improve the sensitivity of off-hand detection, this invention proposes a direction control device, a method for detecting off-hand touch information, a system, and a vehicle. The direction control device is configured such that its outer surface generates an electrical conductivity when in contact with the skin, so that as long as the skin touches the outer surface of the direction control device, a change in the electrical signal generated by the direction control device can be triggered.

[0005] This invention is achieved through the following technical solution:

[0006] Firstly, a method for detecting the removal of touch information based on a direction control device is provided, for detecting the contact state between the hand and the direction control device; the method for detecting the removal of touch information based on a direction control device includes the following steps:

[0007] An excitation signal is applied to the first conductive layer embedded in the direction control device;

[0008] The first electrical signal generated by the first conductive layer and the second electrical signal generated by the second conductive layer under the induction of the first electrical signal are obtained, wherein the second conductive layer of the direction control device is configured to form a conductive relationship with the hand through direct or indirect contact;

[0009] The contact state between the hand and the direction control device is determined based on the change in the relationship between the first electrical signal and the second electrical signal.

[0010] Optionally, determining the contact state between the hand and the direction control device based on the change in the relationship between the first electrical signal and the second electrical signal specifically includes the following steps:

[0011] A difference signal is generated based on the first electrical signal and the second electrical signal;

[0012] The difference signal is compared with a preset fixed electrical signal to obtain an output signal, and the output signal changes with the amplitude of the second electrical signal.

[0013] The contact state between the hand and the direction control device is determined based on the changes in the output signal.

[0014] Optionally, generating a difference signal based on the first electrical signal and the second electrical signal specifically includes the following steps:

[0015] A first result is obtained by amplifying the driving current of the first electrical signal, and a second result is obtained by amplifying the driving current of the second electrical signal. The difference signal is obtained by performing a differential operation on the first result and the second result.

[0016] Optionally, the first result is obtained through a first in-phase amplifier; the second result is obtained through a second amplifier; and the difference signal is obtained through a subtraction amplifier.

[0017] Optionally, comparing the difference signal with a preset fixed electrical signal to obtain the output signal specifically includes the following steps:

[0018] The difference signal is controlled to be input to the non-inverting input of the comparator, and a fixed electrical signal is controlled to be input to the inverting input of the comparator, so that the output signal is generated through the output terminal of the comparator.

[0019] Optionally, the voltage value of the fixed electrical signal is preset in either of the following two ways:

[0020] When the hand and the second conductive layer do not form a conductive relationship, the voltage value of the difference signal is always higher than the voltage value of the fixed electrical signal. When the hand and the second conductive layer form a conductive relationship, within one cycle of the difference signal, at least for a portion of the time period, the voltage value of the difference signal is lower than the voltage value of the fixed electrical signal.

[0021] When the hand and the second conductive layer do not form a conductive relationship, the voltage value of the difference signal is always lower than the voltage value of the fixed electrical signal. When the hand and the second conductive layer form a conductive relationship, within one cycle of the difference signal, at least for a portion of the time period, the voltage value of the difference signal is higher than the voltage value of the fixed electrical signal.

[0022] Optionally, determining the contact state between the hand and the direction control device based on changes in the output signal specifically includes the following steps:

[0023] Obtain the output signal;

[0024] When the output signal is detected to have a first level or when the output signal is detected to be periodically changing between a first level and a second level, a signal is generated indicating that the hand is on the direction control device. When the output signal is detected to be always at a high level for a preset time period, a signal is generated indicating that the hand is off the direction control device. The preset time period is not less than one cycle of the excitation signal.

[0025] Optionally, the excitation signal is a 400Hz~100KHz square wave signal.

[0026] Secondly, a touch information detection system is provided, which is applied in the touch information removal detection method based on the orientation control device as described in any of the above claims.

[0027] The touch information detection system includes a direction control device;

[0028] The direction control device has a first conductive layer and a second conductive layer that are insulated from each other. The first conductive layer is built into the direction control device, and the second conductive layer is configured to form a conductive relationship with the hand through direct or indirect contact.

[0029] Optionally, the touch information detection system further includes a detection device, which includes a control module and a signal processing module. The output of the control module is used to transmit the excitation signal, and the input of the signal processing module is used to receive the first electrical signal and the second electrical signal. The output of the signal processing module is connected to the input of the control module. The output signal of the signal processing module changes with the amplitude of the second electrical signal. The control module determines the contact state between the direction control device and the skin based on the output signal.

[0030] Thirdly, a direction control device is provided, including a direction control body and a touch-sensitive structure, wherein the touch-sensitive structure includes a first conductive layer and a second conductive layer, and the direction control device uses the touch information off-hand detection method based on the direction control device described in the first aspect of the present invention to perform off-hand detection.

[0031] Fourthly, a vehicle is provided, including the touch information detection system as described in the second aspect above or the steering control device as described in the third aspect.

[0032] The present invention has the following beneficial effects:

[0033] In this invention, the direction control device is configured as a device having a first conductive layer and a second conductive layer that are mutually insulated. After an excitation signal is emitted to the first conductive layer, the first conductive layer generates a first electrical signal under the influence of its equivalent capacitance to ground. The second conductive layer generates a second electrical signal under the influence of the first electrical signal. When the skin forms a conductive relationship with the second conductive layer, the human body capacitance causes a change in the second electrical signal. The contact state between the hand and the direction control device is determined based on the change in the relationship between the first and second electrical signals, which has higher sensitivity than capacitive sensor measurement technology. Attached Figure Description

[0034] To more clearly illustrate the embodiments of the present invention, the relevant accompanying drawings will be briefly described below. It should be understood that the drawings described below are only for illustrating some embodiments of the present invention, and those skilled in the art can obtain many other technical features and connections not mentioned herein based on these drawings.

[0035] Figure 1 This is a cross-sectional view of one position of the touch-sensitive structure according to an embodiment of the present invention.

[0036] Figure 2 This is a cross-sectional view of another location of a touch-sensitive structure according to an embodiment of the present invention;

[0037] Figure 3 This is a cross-sectional view of a partial unfolded portion of a touch-sensitive structure according to an embodiment of the present invention;

[0038] Figure 4 This is a cross-sectional view of a partial unfolded portion of a touch-sensitive structure according to an embodiment of the present invention;

[0039] Figure 5 This is a diagram showing the correspondence of a steering wheel device according to an embodiment of the present invention. Part a is a cross-sectional view of a portion of the steering wheel device after it has been unfolded, and part b is a cross-sectional view of a portion of the steering wheel device.

[0040] Figure 6 This is a schematic diagram of a steering wheel device according to an embodiment of the present invention;

[0041] Figure 7 This is a cross-sectional view of a partial location of a touch information detection system according to an embodiment of the present invention.

[0042] Figure 8 This is a cross-sectional view of a partial location of a touch information detection system according to an embodiment of the present invention.

[0043] Figure 9 This is a schematic diagram of a touch information detection system according to an embodiment of the present invention;

[0044] Figure 10 This is a schematic diagram of a touch information detection system according to an embodiment of the present invention;

[0045] Figure 11 This is a circuit diagram of a touch information detection system according to an embodiment of the present invention;

[0046] Figure 12 This is an excitation signal diagram of a touch information detection system according to an embodiment of the present invention;

[0047] Figure 13 This is a first electrical signal diagram of a touch information detection system according to an embodiment of the present invention;

[0048] Figure 14 This is a second electrical signal diagram of a touch information detection system according to an embodiment of the present invention;

[0049] Figure 15 This is a difference signal diagram of a touch information detection system according to an embodiment of the present invention;

[0050] Figure 16 This is a comparison diagram of the differential signal and the fixed electrical signal when the hand is not in contact with the steering wheel in one embodiment of the present invention;

[0051] Figure 17 This is a comparison diagram of the time difference signal and the fixed electrical signal when the hand touches the steering wheel in one embodiment of the present invention;

[0052] Figure 18 This is a flowchart of a touch information removal detection method based on a direction control device according to an embodiment of the present invention;

[0053] Figure 19 This is a flowchart of a touch information removal detection method based on a direction control device according to an embodiment of the present invention.

[0054] The reference numerals and names in the figure are as follows:

[0055] 1. First insulating substrate; 11. First surface; 12. Second surface; 2. First conductive layer; 21. Inner clearance through hole; 3. Second conductive layer; 31. Outer clearance through hole; 4. Second insulating substrate; 5. Third conductive layer; 6. Steering wheel hub; 61. Hand operation area; 7. Insulating spacer layer; 8. Detection device; 81. First wire; 82. Second wire; 83. First rivet; 84. First washer; 85. Second rivet; 86. Second washer. Detailed Implementation

[0056] The technical solutions of the present invention will be described in detail below with reference to the accompanying drawings.

[0057] Before further explanation, let’s first explain the term “touch-type” in this invention. The object being touched is the “touch-type sensing structure” described below. The object being touched generally refers to any part of the human body with skin. The human body is not limited to the skin of the hands, feet and face. For ease of description, the object being touched will be referred to as “control unit” in the following description.

[0058] This invention is based on the technical concept that a conductive relationship is formed when the skin and the product surface come into contact, and the opening and closing of this conductive relationship causes a change in the electrical signal output by the product. It proposes a touch-sensitive structure that can be laid on the surface of an object. When the skin comes into contact with the touch-sensitive structure, at least one of the electrical signals generated by the touch-sensitive structure changes. Further analysis of the change in the electrical signal can detect the contact relationship between the skin and the product.

[0059] refer to Figure 1 and Figure 2 This invention provides a touch-sensitive structure, including a first insulating substrate 1, a first conductive layer 2, and a flexible second conductive layer 3. The first insulating substrate 1 is made of a flexible material and has corresponding first surfaces 11 and second surfaces 12. The first conductive layer 2 is disposed on the first surface 11; the first conductive layer 2 can be attached to the first insulating substrate 1, or it can simply be bonded to the first insulating substrate 1; the first conductive layer 2 can be disposed adjacent to the first surface 11, or it can be indirectly connected to the first surface 11 through other structures, that is, there can be other layers between the first conductive layer 2 and the first surface 11.

[0060] The second conductive layer 3 is attached to the first insulating substrate 1. Specifically, the second conductive layer 3 is attached to the first insulating substrate 1 by a processing technology, such as coating a conductive material onto the second surface 12 to form the second conductive layer 3, or by bonding a film-like second conductive layer 3 onto the second surface 12.

[0061] In some embodiments, the first or second conductive layer located in the inner layer may be made of a conventional conductive material. The following example illustrates this by taking the second conductive layer 3 located in the outer layer that is directly accessible to the control part (e.g., a finger).

[0062] In use, the second conductive layer 3 is closer to the control unit than the first conductive layer 2; the second conductive layer 3 is configured to form a conductive relationship with the control unit through direct or indirect contact; compared with capacitive electrodes, the second conductive layer 3 is more sensitive to the control unit. As long as a local part of the control unit (such as a finger) touches (including direct and indirect contact) the second conductive layer 3, the electrical signal generated by the second conductive layer 3 will change, thus the touch sensing structure has higher sensitivity.

[0063] The first conductive layer 2 forms an equivalent capacitance to ground. When an excitation signal is applied to the first conductive layer 2, a new electrical signal is generated under the action of the equivalent capacitance. The new electrical signal changes in parameters relative to the excitation signal. The first conductive layer 2 and the second conductive layer 3 are insulated from each other by the first insulating substrate 1. Therefore, after the first conductive layer 2 generates an electrical signal, it will affect the second conductive layer 3 to also generate an electrical signal. In this embodiment of the invention, one of the first conductive layer 2 and the second conductive layer 3 is used to receive the excitation signal and generate a first electrical signal according to the excitation signal, and the other is used to generate a second electrical signal according to the first electrical signal. For example, after an excitation signal is applied to the first conductive layer 2, the first conductive layer 2 generates a first electrical signal, and the second conductive layer 3 generates a second electrical signal under the action of the first electrical signal. The DC bias of the first electrical signal and the second electrical signal are the same.

[0064] The human body acts like a capacitor. When the control unit is not in contact with the second conductive layer 3, the second electrical signal is unaffected and has a large amplitude. However, when the control unit forms a conductive relationship with the second conductive layer 3, the amplitude of the second electrical signal decreases due to the influence of the human body's capacitance. In other words, the amplitude of the second electrical signal varies depending on the contact relationship between the control unit and the second conductive layer 3. The touch-sensitive structure, combined with the control unit, can calculate the relationship between the first and second electrical signals to determine whether the hand is released.

[0065] The touch-sensitive structure is flexible; correspondingly, the structure formed by the first insulating substrate 1, the first conductive layer 2, and the second conductive layer 3 is also flexible, allowing it to adhere to the surface of an object and be used as a wrapping material. This enables a person to directly or indirectly contact the second conductive layer 3 and establish a conductive relationship with it. Of course, the touch-sensitive structure also serves as an interior decoration feature.

[0066] As can be seen from the above description, the flexible touch sensing structure provided by the present invention has a first conductive layer 2 and a second conductive layer 3 respectively insulatingly arranged on both sides of the first insulating substrate 1, and the flexible second conductive layer 3 can form an electrical connection or electrical connection with the control part, and one of the conductive layers can receive an excitation signal, providing structural support for detecting whether the second conductive layer 3 is in contact with the control part. When the touch sensing structure is applied to the surface of an object, it can detect the contact between the object and the control part.

[0067] In this embodiment of the invention, the first conductive layer 2 can cover the entire first surface 11 or partially cover the first surface 11. It should be noted that the first conductive layer 2 covers the first surface 11 as a whole, but some small holes are reserved on the first conductive layer 2 for connection or avoidance reasons. From the perspective of those skilled in the art, when the area of ​​these small holes is much smaller than the area of ​​the first surface 11, although the first surface 11 is not covered at the position of these small holes, this situation is also understood as the first conductive layer 2 covering the entire first surface 11.

[0068] In this embodiment of the invention, the second conductive layer 3 can cover the entire second surface 12 or partially cover the second surface 12. It should be noted that the second conductive layer 3 covers the second surface 12 as a whole, but some small holes are reserved on the second conductive layer 3 for connection or avoidance reasons. From the perspective of those skilled in the art, when the area of ​​these small holes is much smaller than the area of ​​the second surface 12, although the second surface 12 is not covered at the position of these small holes, this situation is also understood as the second conductive layer 3 covering the entire second surface 12.

[0069] In some embodiments, only one layer, the first insulating substrate 1, is disposed between the first conductive layer 2 and the second conductive layer 3. In other embodiments, multiple layers are disposed between the first conductive layer 2 and the second conductive layer 3, as long as the insulating relationship between the first conductive layer 2 and the second conductive layer 3 is maintained.

[0070] In some embodiments, the touch-sensitive structure includes a first conductive skin, on which a first insulating substrate 1 and a second conductive layer 3 are provided. The insulating portion of the first conductive skin is the first insulating substrate 1, and the conductive portion located on the second surface 12 of the insulating portion is the second conductive layer 3. The conductive skin has high sensitivity; a single finger touching the second conductive layer 3 can cause a change in the second electrical signal. Using a leather material to cover the surface of an object provides a better tactile experience for the control unit.

[0071] In some embodiments, the first conductive layer uses a double-layer conductive layer, with the first conductive layer 2 also being part of the first conductive layer. The cost of the double-layer conductive layer is lower than that of capacitive sensor measurement technology (around 60 yuan), thus giving the touch sensing structure a price advantage. For example... Figure 3As shown, in some other embodiments, as a first alternative, the first conductive layer is a single-layer conductive layer, and the touch-sensitive structure also includes a single-layer second conductive layer. The second conductive layer has a first conductive layer 2 and a second insulating substrate 4, such that the first conductive layer 2 is bonded to the first insulating substrate 1 (in some other embodiments, the second insulating substrate 4 can also be directly bonded to the first insulating substrate 1). In some other embodiments, as a second alternative, the first conductive layer is a single-layer conductive layer, and the first conductive layer 2 is made of metal conductive cloth. In some other embodiments, as a third alternative, the first conductive layer 2 is made of metal foil, that is, the first conductive layer 2 can be made of other existing conductive materials.

[0072] In this embodiment of the invention, the second conductive layer 3 can be used as a touch layer, allowing the control unit to directly contact the second conductive layer 3. Alternatively, one or more new conductive layers can be coated on the second conductive layer 3, with the outermost new conductive layer serving as the touch layer. The control unit indirectly contacts the second conductive layer 3 through this new conductive layer. This method allows for adjustment of the sensitivity of the touch-sensitive structure. Specifically, as... Figures 1 to 3 As shown, the second conductive layer 3 is exposed, allowing the control unit to directly contact it, thus achieving higher sensitivity by utilizing the good conductivity of the conductive layer. Figure 4 As shown, as an alternative, the surface of the second conductive layer 3 is coated with a third conductive layer 5. The conductivity of the third conductive layer 5 is lower than that of the second conductive layer 3. The third conductive layer 5 is exposed, and the control unit achieves electrical connection with the second conductive layer 3 by directly touching the third conductive layer 5.

[0073] The first and second electrical signals generated by the touch-sensitive structure are transmitted through wires. Correspondingly, the first conductive layer 2 and the second conductive layer 3 need to establish an electrical connection with the wires, and it is necessary to prevent the first conductive layer 2 and the second conductive layer 3 from becoming electrically conductive. For example... Figure 1 As shown, the second conductive layer 3 has an external clearance through-hole 31, which serves as a connection clearance space between the first conductive layer 2 and its corresponding wire, to prevent electrical conduction between the first conductive layer 2 and the second conductive layer 3; as Figure 2 As shown, the first conductive layer 2 has an inner clearance through hole 21, which serves as a connection clearance space between the second conductive layer 3 and its corresponding wire, to prevent electrical conduction between the first conductive layer 2 and the second conductive layer 3; the outer clearance through hole 31 and the inner clearance through hole 21 can be at least partially staggered, thereby further improving the reliability of the touch sensing structure.

[0074] The above details the touch-sensitive structure. Although the present invention proposes the above-mentioned touch-sensitive structure based on improving the accuracy of hand-off detection of the vehicle steering wheel, it can be understood from the design concept of the present invention and common knowledge that the touch-sensitive structure can be set on any object that needs to make contact with the skin. For example, the touch-sensitive structure can be applied to the surface of wearable devices, or it can be set on the pedals, or it can be set on the steering control device (such as the steering wheel device, handle).

[0075] refer to Figure 5 Understood. This invention also provides another steering wheel device, including the touch-sensitive structure and steering wheel hub 6 provided in any of the above embodiments, with the touch-sensitive structure covering the surface of the steering wheel hub 6.

[0076] The steering wheel hub 6 has a hand operation area 61 for applying force to the steering wheel hub 6, such as Figure 6 As shown, hand operation areas 61 are provided on the left and right sides of the steering wheel, the touch-sensitive structure covers at least a part of the surface of the steering wheel, and the second conductive layer 3 covers all hand operation areas 61.

[0077] In some embodiments, the touch-sensitive structure covers the entire outer surface of the steering wheel hub 6, and the second conductive layer 3 also covers the entire outer surface of the steering wheel hub 6. Any hand placed on the steering wheel hub 6 can be detected, thus obtaining accurate hand-off information.

[0078] In some other embodiments, as an alternative, the touch-sensitive structure only covers the hand operation area 61 of the steering wheel hub 6, the second conductive layer 3 covers all hand operation areas 61, and the other areas of the steering wheel hub 6 are wrapped with interior trim to achieve a visual style effect different from the previous two alternative methods.

[0079] refer to Figure 5 Understood. In some embodiments, the steering wheel device further includes an insulating spacer layer 7, with an insulating spacer layer 7 separating the touch-sensitive structure and the steering wheel hub 6. The steering wheel hub 6 is grounded, forming an equivalent capacitance with the first conductive layer 2 (or, as can be understood, the first conductive layer 2 and ground forming an equivalent capacitance). Therefore, after an excitation signal is applied to the first conductive layer 2, the rise and fall edges of the first electrical signal become slower relative to the excitation signal (see reference). Figure 12 and Figure 13 (Understood). The insulating spacer layer 7 can be made of foam or insulating cloth.

[0080] This invention also provides a steering control device, which can be installed on a vehicle to control the vehicle's direction of travel. The steering control device can be the aforementioned steering wheel device, handle, or other products used to control direction. The steering control device includes a touch-sensitive structure and a steering control body as provided in any of the above embodiments, with the touch-sensitive structure encased in the steering control body. The steering control body is the core component used to control direction; vehicle direction control can be achieved by moving the steering control body (e.g., rotating, flipping, and linear movement). When the steering control device is a steering wheel device, the steering control body is the steering wheel body, which includes the aforementioned steering wheel hub 6.

[0081] In some embodiments, the second conductive layer 3 covers the entire outer surface of the direction control body, allowing detection of any surface location where the control unit contacts the direction control device, thus more reliably determining whether the control unit has contacted the touch-sensitive structure. In other embodiments, as a first alternative, the direction control body has a direction control operation area (equivalent to the hand operation area 61 in a steering wheel device), and the control unit controls the direction by applying force to the direction control operation area. The second conductive layer 3 is disposed at the position corresponding to the direction control operation area, and the other surfaces of the direction control body do not have touch-sensitive structures. In other embodiments, as a second alternative, the difference from the first alternative is that the entire surface of the direction control body is covered with a touch-sensitive structure, but the second conductive layer 3 is only present at the position of the direction control operation area.

[0082] It should be emphasized that the touch sensing structure with a double conductive layer on the steering control body also has a strong anti-interference effect. Specifically, when the touch sensing structure and the heating device are used together on the steering wheel, the heating device heats the steering wheel and generates electromagnetic interference. This electromagnetic interference has a small impact on the second conductive layer 3. Compared with the single conductive layer sensing structure, the touch sensing structure provided in any of the above embodiments has a stronger anti-interference ability against this electromagnetic interference.

[0083] This invention also provides a touch information detection system, including a detection device 8 and a direction control device provided in any of the above embodiments. The first conductive layer 2 and the second conductive layer 3 are electrically connected to the detection device 8. The detection device 8 is used to emit an excitation signal and to determine the hand-off status of the second conductive layer 3 by analyzing the second electrical signal or the relationship between the first and second electrical signals. It is readily understood that the detection device 8 includes a control module to realize the functions of emitting the excitation signal and determining the hand-off status. The control module can be implemented using various types of processing chips in the prior art, such as a microcontroller (MCU) or a programmable logic controller (PLC). For example, a chip of model AC78013MDQA can be used. The signal algorithm programmed into the control module has already been described in well-known technical solutions in the field of steering wheel hand-off detection and is not the focus of this invention; therefore, it will not be elaborated further.

[0084] Based on the above technical solution, the detection device 8 of the present invention may further include a first wire 81 and a second wire 82; the first wire 81 is fixedly connected to the touch-sensitive structure through a first fixing structure, the first wire 81 is electrically connected to the first conductive layer 2, and is insulated from the second conductive layer 3. The second wire 82 is fixedly connected to the touch-sensitive structure through a second fixing structure, the second wire 82 is electrically connected to the second conductive layer 3, and is insulated from the first conductive layer 2. The positional relationship between the first wire 81 and the second wire 82 and the steering wheel hub 6 is referenced. Figure 6 The connection relationship between the first wire 81 and the second wire 82 and the contact induction structure is referenced. Figure 7 and Figure 8 .

[0085] refer to Figure 7 Understood. In some embodiments, the first fixing structure includes a first rivet 83 and a first washer 84. The first rivet 83 passes through the first washer 84, the first conductive layer 2, and the first insulating substrate 1 in sequence at the outer clearance through hole 31 of the second conductive layer 3. The first wire 81 is pressed between the head of the first rivet 83 and the first washer 84. The first rivet 83 and the first conductive layer 2 are in contact to form a conductive relationship. The first rivet 83 and the second conductive layer 3 are not in contact to insulate them from each other, or an insulating part is arranged between the first rivet 83 and the second conductive layer 3 to insulate them from each other.

[0086] refer to Figure 8Understood. In some embodiments, the second fixing structure includes a second rivet 85 and a second washer 86. The second rivet 85 passes sequentially through the second washer 86, the second conductive layer 3, and the first insulating substrate 1 at the inner clearance through hole 21 of the first conductive layer 2. The second wire 82 is pressed between the head of the second rivet 85 and the second washer 86. The second rivet 85 and the second conductive layer 3 are in contact to form a conductive relationship. The second rivet 85 and the first conductive layer 2 do not contact each other to keep them insulated from each other. Of course, in some embodiments, an insulating part can also be arranged between the second rivet 85 and the first conductive layer 2 to keep them insulated from each other. There are many ways to keep them in contact in the above embodiments, such as through holes, or the length of the rivet cannot extend to the first conductive layer or the second conductive layer.

[0087] In other embodiments, considering that the second electrical signal is relatively weak and also contains noise, the first and second electrical signals can be calculated to obtain their relationship, and then the contact status between the control unit and the second conductive layer 3 can be determined based on the change in the relationship, so as to obtain a more accurate contact status.

[0088] refer to Figure 9 To understand this, the detection device 8 may also include a control module and a signal processing module. The output of the control module is used to transmit the aforementioned excitation signal to the first conductive layer 2. The first conductive layer 2 generates a first electrical signal under the influence of the steering wheel hub 6, and the second conductive layer 3 generates a second electrical signal under the influence of the first electrical signal. The input of the signal processing module is used to receive the first and second electrical signals. The signal processing module processes the first and second electrical signals to generate an output signal. The output of the signal processing module is connected to the input of the control module. The output signal of the signal processing module changes with the change of the second electrical signal. The control module determines the hands-off information of the steering control device based on the output signal.

[0089] refer to Figure 9 and Figure 10 Understood. In some embodiments, the signal processing module includes a subtraction unit and a comparison unit. The subtraction unit obtains a difference signal based on a first electrical signal and a second electrical signal. For example, the subtraction unit directly performs a subtraction operation on the first and second electrical signals to obtain the difference signal. Alternatively, the subtraction unit processes the first electrical signal to obtain a first result, processes the second electrical signal to obtain a second result, and then performs a subtraction operation on the first and second results and amplifies them to obtain the difference signal. The comparison unit compares the difference signal with a fixed electrical signal and obtains an output signal. The fixed electrical signal is a pre-set threshold for the comparison unit. In a transient state, the output result corresponding to the difference signal being greater than the fixed electrical signal is different from the output result corresponding to the difference signal being less than the fixed electrical signal. Thus, the control module can determine the contact status between the control unit and the second conductive layer 3 through the change information of the output signal.

[0090] refer to Figure 11 Understood. In some embodiments, the subtraction unit includes a first non-inverting amplifier, a second non-inverting amplifier, and a subtraction amplifier. The first non-inverting amplifier is used to increase the drive current of the first electrical signal and output the first result described above; the second non-inverting amplifier is used to increase the drive current of the second electrical signal and output the second result described above. Based on the above information, it can be seen that the DC bias of the first result and the second result is the same. The inverting input of the subtraction amplifier is connected to the output of the first non-inverting amplifier, the non-inverting input of the subtraction amplifier is connected to the output of the second non-inverting amplifier, and the output of the subtraction amplifier is connected to the comparator unit. The subtraction amplifier performs a difference operation on the first result and the second result and amplifies it to obtain the difference signal.

[0091] The first non-inverting amplifier includes resistors R1 and R2, and operational amplifier U1. The non-inverting input of operational amplifier U1 is connected to a first wire 81, and the inverting input of operational amplifier U1 is connected between resistors R1 and R2 connected in series. The output of operational amplifier U1 is also connected to the other end of resistor R2, and the other end of resistor R1 is grounded. The second non-inverting amplifier includes resistors R3 and R4, operational amplifier U2, resistors R11, R12, and R13. Resistors R11 and R12 form a voltage divider circuit, and the voltage divider terminal is connected to the non-inverting input of operational amplifier U2 through resistor R13. A second wire 82 is connected between resistor R13 and the non-inverting input of operational amplifier U2. The output of operational amplifier U2 is also connected to resistor R4. The subtraction amplifier includes resistors R6, R7, and R8, as well as operational amplifier U3. The output of operational amplifier U1 is connected to the inverting input of operational amplifier U3 via resistor R5. The output of operational amplifier U2 is connected to the non-inverting input of operational amplifier U3 via resistor R7. Resistor R8 is connected between resistor R7 and the non-inverting input of operational amplifier U3. One end of resistor R6 is connected between resistor R5 and operational amplifier U3, and the other end is connected to the output of operational amplifier U3.

[0092] The comparison unit includes comparator U4 and a comparison circuit. The comparison circuit outputs a fixed electrical signal to the inverting input of the comparator, and the non-inverting input of the comparator is connected to the output of the subtraction amplifier. The comparison circuit includes resistors R9 and R10. The inverting input of comparator U4 is connected between resistors R9 and R10, the non-inverting input of comparator U4 is connected to the output of operational amplifier U3, and the output of comparator U4 is connected to the input of the control module.

[0093] The output of the control module is connected to the non-inverting input of operational amplifier U1 via resistor R14. A first wire 81 is connected between resistor R14 and operational amplifier U1, so that after the control module transmits an excitation signal, the non-inverting input of operational amplifier U1 receives the first electrical signal instead of the excitation signal. The input of the control module receives the output signal of comparator U4. The control module analyzes the output signal to determine the contact status of the control unit and the second conductive layer 3. When the control module determines that the control unit has been removed from the hand, it can send an alarm command to the alarm device of the touch information detection system and a display command to the display device of the touch information detection system.

[0094] When a touch information detection system is applied to a car, it is used to detect when the steering wheel is removed from the hands; this can also be called a steering wheel hands-off detection system. The structure of the hands-off detection system is described in the above introduction to touch information detection systems. The following section will refer to the appendix... Figures 11 to 17 The working principle of the steering wheel hands-off detection system is systematically explained, including... Figures 12-17 In the diagram, the horizontal axis represents time t, and the vertical axis represents the electrical signal or voltage signal V.

[0095] The control module outputs an excitation signal, which is a 400Hz~100KHz square wave signal, such as... Figure 12 As shown. The excitation signal is transmitted to the first conductive layer 2 after passing through resistor R14. The influence of the steering wheel hub 6 on the excitation signal formation parameters causes the rising and falling edges of the waveform to become slower, causing the first conductive layer 2 to generate a first electrical signal, such as... Figure 13 As shown. The first electrical signal is input to the non-inverting input of operational amplifier U1 through the first wire 81, and operational amplifier U1 outputs the first result. The second conductive layer 3 is induced by the first electrical signal to generate a second electrical signal with the same DC bias, and the waveform of the second electrical signal is as shown. Figure 14 As shown, the second electrical signal is input to the non-inverting input of operational amplifier U2 through the second wire 82, and operational amplifier U2 outputs the second result. The first and second results are fed into operational amplifier U3 for difference calculation, and operational amplifier U3 outputs the difference signal, as shown. Figure 15 As shown, comparator U4 combines the difference signal and the fixed electrical signal to generate an output signal, which is then transmitted to the input of the control module.

[0096] refer to Figure 16 Understood. When the hand is not in contact with the second conductive layer 3, the second conductive layer 3 is unaffected. The second electrical signal is relatively larger, while the difference between the first and second electrical signals is smaller. The amplitude of the difference signal is relatively small and cannot fall below the preset fixed electrical signal. Therefore, the non-inverting input of comparator U4 is higher than the inverting input, and comparator U4 always outputs a high level. It should be noted that... Figure 16The diagram illustrates differential signals and fixed electrical signals. The horizontally extended signal represents the fixed electrical signal, while the periodically changing signal with rising and falling edges represents the differential signal.

[0097] refer to Figure 17 Understanding. When the hand operates the steering wheel, a conductive relationship is established between the hand and the second conductive layer 3. Due to the influence of the human body's capacitance, the amplitude of the second electrical signal decreases, while the difference between the first and second electrical signals increases. The amplitude of the difference signal increases, and its trough is lower than that of the fixed electrical signal. The output signal corresponding to the portion of the input at the non-inverting input of comparator U4 that is lower than that at the inverting input is low-level, meaning that the output signal has both low-level and high-level phases within one signal cycle. When the control module detects a low-level input or an input signal with alternating high and low levels, it determines that the hand is on the steering wheel. When the control module detects that the input is consistently high-level within a preset time period, and the preset time period is not less than one cycle of the excitation signal, it can determine that the hand has been removed from the steering wheel. It should be noted that... Figure 17 The diagram illustrates the difference signal and the fixed electrical signal. The horizontally extended signal represents the fixed electrical signal, while the periodically changing signal with rising and falling edges represents the difference signal. The difference signal changes from a high level to a low level. When the voltage value of the difference signal is greater than that of the fixed electrical signal, comparator U4 outputs a high level. When the voltage value of the difference signal is less than that of the fixed electrical signal, comparator U4 outputs a low level. When the control module receives a low-level electrical signal within a preset time period, the hand is not removed from the steering wheel.

[0098] This invention also provides a vehicle, including the touch information detection system or the direction control device provided in any of the above embodiments. The number of wheels is not limited; three-wheeled vehicles, four-wheeled vehicles (such as automobiles), and vehicles with other numbers of wheels are all acceptable. The power source of the vehicle is not limited; gasoline, diesel, electric, and hybrid power are all acceptable. The application scenario of the vehicle is not limited; it can carry passengers or cargo.

[0099] This invention also provides a touch information removal detection method based on a direction control device (hereinafter referred to as the "detection method"), used to detect the contact state between the skin and the direction control device provided in any of the above embodiments. Correspondingly, the touch information detection system with a direction control device provided in any of the above embodiments can also be applied to the detection method. To avoid repetition, the hardware-related parts of the description of the detection method refer to the above description of the touch sensing structure, direction control device, and touch information detection system, as well as the appendix. Figures 1 to 17 Accordingly, the reference numerals used in the following figures are shown in the appendix. Figures 1 to 17 .

[0100] As can be seen from the above description of the direction control device, the direction control device has a first conductive layer and a second conductive layer that are mutually insulated. The first conductive layer is built into the direction control device, and the second conductive layer is configured to form a conductive relationship with the hand through direct or indirect contact.

[0101] Combination Figure 1-19 Understood. The detection method of this invention includes the following steps:

[0102] S10. Apply an excitation signal to the first conductive layer 2; the excitation signal is a 400Hz~100KHz square wave signal. As mentioned above, the first conductive layer 2 is built into the direction control device, and the excitation signal is emitted by the control module.

[0103] S20. Obtain the first electrical signal generated by the first conductive layer 2 and the second electrical signal generated by the second conductive layer 3. The principle of generating the first and second electrical signals is described above in the explanation of the touch sensing structure, direction control device and touch information detection system.

[0104] S30. Determine the contact state between the hand and the direction control device based on the change in the relationship between the first electrical signal and the second electrical signal.

[0105] Specifically, step S30, which involves determining the contact state between the hand and the direction control device based on the change in the relationship between the first and second electrical signals, includes the following steps:

[0106] S31. Generate a difference signal based on the first electrical signal and the second electrical signal. Specifically, this step includes: amplifying the drive current of the first electrical signal through a first inverting amplifier to obtain a first result; amplifying the drive current of the second electrical signal through a second amplifier to obtain a second result; and performing a differential operation on the first result and the second result through a subtraction amplifier to obtain the difference signal.

[0107] S32. The difference signal is compared with a preset fixed electrical signal to obtain an output signal. The output signal is set to change with the amplitude of the second conductive layer.

[0108] One way to obtain the output signal by comparing the difference signal with a preset fixed electrical signal is to control the difference signal to be input to the non-inverting input of the comparator, control the fixed electrical signal to be input to the inverting input of the comparator, and generate the output signal through the output of the comparator.

[0109] The voltage value of the fixed electrical signal is preset to be: when the hand and the second conductive layer do not form a conductive relationship, the voltage value of the difference signal is always higher than the voltage value of the fixed electrical signal; when the hand and the second conductive layer form a conductive relationship, within one cycle of the difference signal, at least for a portion of the time period, the voltage value of the difference signal is lower than the voltage value of the fixed electrical signal.

[0110] S33. Determine the contact state between the hand and the direction control device based on changes in the output signal. This step specifically includes the following steps:

[0111] S331. Obtain the output signal through the control module;

[0112] S332. When a low level is detected in the output signal or when the output signal is detected to be periodically changing between high and low levels, a signal is generated indicating that the hand is on the direction control device. When the output signal is detected to be high for a preset time period, a signal is generated indicating that the hand is off the direction control device. The preset time period is not less than one cycle of the excitation signal.

[0113] The above embodiments illustrate the case where the hand-off signal is high-level. That is, if the control module input detects a low-level signal within a preset time period, the hand is on the steering wheel; if a high-level signal is consistently detected, the hand is considered to have left the steering wheel. Of course, in some embodiments, if the hand-off signal is low-level, then if the control module consistently detects a low level, the hand is considered to have left the steering wheel. This can be achieved by adjusting the voltage connected to the inverting input of the comparator and the bias voltage of the non-inverting input of amplifier U2. Therefore, determining whether the hand has left the steering wheel by detecting a consistently low-level signal within a preset time period constitutes an equivalent embodiment of the high-level detection method described above. When a low-level signal is used for hand-off detection, correspondingly, when the hand and the second conductive layer do not form a conductive relationship, the voltage value of the difference signal is always lower than the voltage value of the fixed signal. When the hand and the second conductive layer form a conductive relationship, within one cycle of the difference signal, at least for a portion of the time period, the voltage value of the difference signal is higher than the voltage value of the fixed signal. At this time, when a high-level signal or a periodic change between a low-level signal and a high-level signal is detected, it is considered that the hand is on the steering wheel. When a low-level signal is detected continuously within a preset cycle, it is considered that the hand has been removed from the steering wheel.

[0114] It should be understood that in this application, the control module outputs an excitation signal to the first conductive layer or the second conductive layer to obtain the changes in the electrical signals of the first conductive layer and the second conductive layer respectively. Then, the difference signal is obtained by subtraction operation, and the difference signal and the preset electrical signal are connected to the comparator and the signal is output.

[0115] The hand-off detection method described in this application can sensitively detect the contact between a single finger and the second conductive layer. When a single finger contacts the second conductive layer of the direction control device, the amplitude of the second electrical signal increases, allowing the control module to receive a first-level signal within a preset time threshold. Once the hand no longer contacts the direction control device, the control device continuously receives the second-level signal within the preset time threshold, thus determining that the hand has left the direction control device. This application can keenly sense changes in electrical signals, improving the sensitivity of hand-off detection. In specific implementation, based on the above idea, the entire... Figure 11 The circuit structure in this application can be transformed or modified by equivalent means. By using electronic components such as operational amplifiers, differentials, and comparators, various circuits with the same function as this application can be constructed. This application will not elaborate on this part.

[0116] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for detecting the removal of a hand from a touch information device based on a directional control device, used to detect the contact state between the hand and the directional control device, characterized in that, The touch information release detection method based on a direction control device includes the following steps: An excitation signal is applied to the first conductive layer embedded in the direction control device; The first electrical signal generated by the first conductive layer and the second electrical signal generated by the second conductive layer under the induction of the first electrical signal are obtained, wherein the second conductive layer of the direction control device is configured to form a conductive relationship with the hand through direct or indirect contact; A difference signal is generated based on the first electrical signal and the second electrical signal; The difference signal is compared with a preset fixed electrical signal to obtain an output signal, and the output signal changes with the amplitude of the second electrical signal. The contact state between the hand and the direction control device is determined based on the changes in the output signal.

2. The touch information removal detection method based on a direction control device as described in claim 1, characterized in that, Generating a difference signal based on the first electrical signal and the second electrical signal specifically includes the following steps: A first result is obtained by amplifying the driving current of the first electrical signal, and a second result is obtained by amplifying the driving current of the second electrical signal. The difference signal is obtained by performing a differential operation on the first result and the second result.

3. The touch information removal detection method based on a direction control device as described in claim 2, characterized in that, The first result is obtained through a first in-phase amplifier; the second result is obtained through a second amplifier; and the difference signal is obtained through a subtraction amplifier.

4. The touch information removal detection method based on a direction control device as described in claim 1, characterized in that, The process of comparing the difference signal with a preset fixed electrical signal to obtain the output signal specifically includes the following steps: The difference signal is controlled to be input to the non-inverting input of the comparator, and a fixed electrical signal is controlled to be input to the inverting input of the comparator, so that the output signal is generated through the output terminal of the comparator.

5. The touch information removal detection method based on a direction control device as described in claim 4, characterized in that, The voltage value of the fixed electrical signal is preset in either of the following two ways: When the hand and the second conductive layer do not form a conductive relationship, the voltage value of the difference signal is always higher than the voltage value of the fixed electrical signal. When the hand and the second conductive layer form a conductive relationship, within one cycle of the difference signal, at least for a portion of the time period, the voltage value of the difference signal is lower than the voltage value of the fixed electrical signal. When the hand and the second conductive layer do not form a conductive relationship, the voltage value of the difference signal is always lower than the voltage value of the fixed electrical signal. When the hand and the second conductive layer form a conductive relationship, within one cycle of the difference signal, at least for a portion of the time period, the voltage value of the difference signal is higher than the voltage value of the fixed electrical signal.

6. The touch information removal detection method based on a direction control device as described in claim 4, characterized in that, The step of determining the contact state between the hand and the direction control device based on changes in the output signal specifically includes the following steps: Obtain the output signal; When the output signal is detected to have a first level or when the output signal is detected to be periodically changing between a first level and a second level, a signal is generated indicating that the hand is on the direction control device. When the output signal is detected to be at the second level for a preset time period, a signal is generated indicating that the hand is off the direction control device. The preset time period is not less than one cycle of the excitation signal.

7. The touch information removal detection method based on a direction control device as described in any one of claims 1 to 6, characterized in that, The excitation signal is a 400Hz~100KHz square wave signal.

8. A touch information detection system, characterized in that, The touch information detection system is applied in the touch information removal detection method based on a direction control device as described in any one of claims 1 to 7; The touch information detection system includes a direction control device; The direction control device has a first conductive layer and a second conductive layer that are insulated from each other. The first conductive layer is built into the direction control device, and the second conductive layer is configured to form a conductive relationship with the hand through direct or indirect contact.

9. The touch information detection system as described in claim 8, characterized in that, The touch information detection system further includes a detection device, which includes a control module and a signal processing module. The output of the control module is used to transmit the excitation signal, and the input of the signal processing module is used to receive the first electrical signal and the second electrical signal. The output of the signal processing module is connected to the input of the control module. The output signal of the signal processing module changes with the amplitude of the second electrical signal. The control module determines the contact state between the direction control device and the skin based on the output signal.

10. A direction control device, characterized in that, The device includes a direction control body and a touch-sensitive structure, wherein the touch-sensitive structure includes a first conductive layer and a second conductive layer, and the direction control device uses the touch information off-hand detection method based on the direction control device according to any one of claims 1-7 to perform off-hand detection.

11. A vehicle, characterized in that, Includes the touch information detection system as described in claim 8 or 9, or the orientation control device as described in claim 10.

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