Self-adaptive capacitive sensor and adjusting method thereof

Abstract

The invention relates to the technical field of seats, in particular to a self-adaptive capacitive sensor and an adjusting system thereof, one or more capacitive sensors are arranged in a seat, and an electrode layer, a first adhesive layer, a dielectric layer, a second adhesive layer and a grounding electrode layer are sequentially stacked on each capacitive sensor in the direction from far to near to a human body. A capacitor is formed between the electrode layer and the grounding electrode layer, and the grounding electrode layer is grounded. The adjusting method comprises the following steps: S1, presetting a comfortable pressure threshold value; presetting a supporting strength threshold value; presetting a tracking sensitivity threshold value; a seat occupying pressure threshold value is preset. And S2, reading a seat occupation sensor, judging whether the seat is occupied or not, and if so, starting an adaptive function. Compared with the prior art, the influence of the human body as an electrode on the capacitive sensor is eliminated, the detection precision is improved, the pressure can be more accurately controlled, the corresponding sensitivity is higher, the pressure change of the human body and the seat is fed back in real time, and the pressure balance of the human body and the seat is kept.

Description

Technical Field

[0001] The invention relates to the technical field of seats, in particular to an adaptive capacitance sensor and an adjustment method thereof. Background Art

[0002] Capacitive sensors are commonly used to detect the capacitance value between the human body and the sensor as the basis for pressure detection. The human body is one of the electrodes, the sensor is the other electrode, and the dielectric material between the two electrodes is human clothing, seat leather, and the comfortable sponge on the leather. When the contact area between the human body and the sensor is large and the contact pressure is small, and when the contact area between the human body and the sensor is small but the contact pressure is large, the capacitance values ​​may be close in these two states. It is impossible to accurately judge the pressure of the human body on the seat, which may lead to misjudgment when the human body moves in a large range. The thickness of human clothing will also affect the detection of capacitance values. When using a barometer as a pressure sensor, when the air bag pressure is relatively small, the pressure change is very small and cannot adapt to the perception of small pressure. The control accuracy is low.

[0003] The adaptive support components can only be inflated to a predetermined pressure when the human body is ready, and cannot maintain the current pressure by following the human body's movements. When the human body's posture changes, the pressure between the body and the seat changes accordingly, and the support changes, which may not be able to effectively support the human body, and easily cause muscle fatigue. Summary of the invention

[0004] In order to solve the problems raised in the above-mentioned background technology, the purpose of the present invention is to provide an adaptive capacitive sensor, including a seat and a capacitive sensor. One or more capacitive sensors are arranged in the seat. The capacitive sensor is stacked with an electrode layer, an adhesive layer one, a dielectric layer, an adhesive layer two and a ground electrode layer in sequence from far to near the human body. A capacitor is formed between the electrode layer and the ground electrode layer, and the ground electrode layer is grounded.

[0005] The dielectric layer is made of elastic material.

[0006] The area of ​​the dielectric layer is greater than or equal to the area of ​​the electrode layer and the area of ​​the grounding electrode layer.

[0007] The area of ​​the ground electrode layer is larger than the area of ​​the electrode layer.

[0008] The electrode layer and the ground electrode layer are provided with electrode pins, and the electrode pins of the ground electrode layer are aggregated into a main pin.

[0009] The adjustment method comprises the following steps:

[0010] S1. Different pressure values ​​are generated according to different acceleration values ​​and bumpy force values ​​of the vehicle under different road conditions, and a comfort pressure threshold is preset; a support strength threshold is preset according to the pressure value that changes due to the movement of the human body caused by the bumps of the vehicle; a tracking sensitivity threshold is preset according to the pressure value reduced by tracking the inflation triggered by the human body leaving the seat according to different groups of people; and a seat occupation pressure threshold is preset according to the pressure value generated by different groups of people occupying the seat.

[0011] S2. Read the seat occupancy sensor to determine whether the seat is occupied. If so, start the adaptive function; if not, do not start the adaptive function.

[0012] The step adaptive function comprises the following steps:

[0013] S21, read the capacitance sensor value and calculate the real-time pressure value.

[0014] S22, determine whether the real-time pressure value is greater than the occupied seat threshold pressure value, if it is determined to be yes, proceed to step S23; if it is determined to be no, repeat step S21.

[0015] S23, start the air pump to inflate the airbag.

[0016] S24, determine whether the real-time pressure value is greater than or equal to the comfortable pressure threshold. If it is determined to be yes, proceed to step S25; if it is determined to be no, repeat step S23.

[0017] S25: The air pump stops inflating and is locked.

[0018] S26, read the capacitance sensor value and calculate the real-time pressure value. The specific formula is the same as step S21.

[0019] S27: Determine whether the real-time pressure value minus the support strength threshold is greater than the comfort pressure threshold. If so, perform the airbag exhaust function; if not, proceed to step S28.

[0020] S28, determine whether the real-time pressure value plus the tracking sensitivity threshold is less than the comfortable pressure threshold. If it is determined to be yes, perform the airbag inflation function, if not, proceed to step S29.

[0021] S29, switch to the hold state, keep the airbag inflated, and return to step S26.

[0022] The pressure threshold of the maintained state in the S29 is provided with a static mode and a dynamic mode. In the static mode, the comfortable pressure threshold is lowered and the tracking sensitivity threshold is increased; in the dynamic mode, the comfortable pressure threshold is increased and the sensitivity threshold is lowered.

[0023] In step S21, the capacitance of the capacitor is calculated using the following formula: C represents the capacitance of the capacitor, "ε" represents the dielectric constant, "S" represents the area covered by the electrode layer and the ground electrode layer 2, "d" represents the distance between the electrode layer and the ground electrode layer, "π" is the circumference of a circle, and "k" is the electrostatic constant. The pressure value is calculated by the change in capacitance.

[0024] The airbag exhaust function in step S27 includes the following steps: S41, exhausting the airbag. S42, judging whether the real-time pressure is less than the comfortable pressure threshold. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S43. S43, judging whether the airbag is empty. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S41.

[0025] The airbag inflation function in step S28 includes the following steps: S31, start the air pump to inflate the airbag. S32, determine whether the real-time pressure value is greater than or equal to the comfortable pressure threshold. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S33. S33, determine whether the airbag is full. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S31.

[0026] Compared with the prior art, the present invention eliminates the influence of the human body as an electrode on the capacitive sensor, improves detection accuracy, can control pressure more accurately, has higher corresponding sensitivity, and can provide real-time feedback on pressure changes between the human body and the seat to maintain pressure balance between the human body and the seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a front view and a cross-sectional view of the structure of the first embodiment of the capacitive sensor;

[0028] Figure 2 It is a front view and a cross-sectional view of the structure of the second embodiment of the capacitive sensor;

[0029] Figure 3 is a schematic diagram of an adaptive capacitive sensor;

[0030] Figure 4 It is a schematic diagram of the structure of the adaptive capacitive sensor system installed on the seat;

[0031] Figure 5 A flowchart of the adjustment method;

[0032] Figure 6 is a flow chart of the adaptive function;

[0033] See also Figure 1 , 1. Dielectric layer, 2. Ground electrode layer, 3. Electrode layer, 4. Adhesive layer 2, 5. Adhesive layer 1, 6. Electrode pin, 7. Total pin. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the accompanying drawings.

[0035] Embodiment 1

[0036] like Figure 1 An adaptive capacitive sensor includes a seat and a capacitive sensor. One or more capacitive sensors are arranged in the seat. The capacitive sensor is stacked with an electrode layer 3, an adhesive layer 1 5, a dielectric layer 1, an adhesive layer 2 4 and a ground electrode layer 2 in order from far to near the human body. The electrode layer 3 and the dielectric layer 1 are connected by the adhesive layer 1 5, and the ground electrode layer 2 and the dielectric layer 1 are connected by the adhesive layer 2 4. The adhesive layer 1 5 and the adhesive layer 2 4 are made of double-sided adhesive materials, and a capacitor is formed between the electrode layer 3 and the ground electrode layer 2. The ground electrode layer 2 is grounded. Multiple capacitive sensors are vertically arranged in the seat, and each capacitive sensor is spaced apart from each other.

[0037] The electrode layer 2 and the ground electrode layer 3 may be made of conductive cloth and / or conductive coating and / or electroplating layer, and the dielectric layer 1 may be made of elastic material to improve the sensitivity of the capacitive sensor and the comfort of the seat.

[0038] The area of ​​the dielectric layer 1 is greater than or equal to the area of ​​the electrode layer 3 and the area of ​​the ground electrode layer 2, thereby improving the accuracy of detection.

[0039] The area of ​​the ground electrode layer 2 is larger than that of the electrode layer 3 to prevent the signal electrode from erroneously detecting the capacitance value of the human body.

[0040] like Figure 3 The capacitance sensor is connected to the capacitor detection control unit, the capacitor detection control unit is connected to a separate LAN cable, a ground cable and a power supply, the airbag is connected to a shape memory alloy drive module (SMA drive module), the SMA drive module is connected to the air pump, and the SMA drive module is connected to a separate LAN cable, a main LAN cable, a ground cable and a power supply.

[0041] The electrode layer 3 and the ground electrode layer 2 are provided with electrode pins 6, which are independently connected to the capacitor detection control unit. The electrode pins 6 of the ground electrode layer 2 are aggregated to a total pin 7, which is then connected to the negative electrode of the capacitor detection control unit.

[0042] like Figure 4 The seat frame, airbag, seat hard foam material, seat soft foam material, heating layer and seat surface material are arranged in sequence from far to near the human body. The capacitive sensor can be arranged between the seat hard foam material and the seat soft foam material, or between the seat soft foam material and the heating layer, so as to improve the stability and durability of the capacitive sensor and enhance the comfort and support of the seat. The ground electrode layer 2 is arranged facing the human body, and the electrode layer 3 is arranged facing the seat soft foam material or the seat hard foam material.

[0043] like Figure 5 to Figure 6 , the adjustment method comprises the following steps:

[0044] S1. Preset a comfort pressure threshold according to different pressure values ​​generated by different acceleration values ​​and bump force values ​​of the vehicle under different road conditions; preset a support strength threshold according to the pressure value that changes due to the movement of the human body caused by the bumps of the vehicle, in order to avoid affecting the airbag pressure retention and prevent incorrect exhaust; preset a tracking sensitivity threshold according to the pressure value reduced by the human body leaving the seat to trigger inflation based on different groups of people; preset a seat occupation pressure threshold according to the pressure value generated by different groups of people occupying the seat.

[0045] S2. Read the seat occupancy sensor to determine whether the seat is occupied. If so, start the adaptive function; if not, do not start the adaptive function.

[0046] The step adaptive function includes the following steps:

[0047] S21, read the capacitance sensor value and calculate the real-time pressure value.

[0048] S22, determine whether the real-time pressure value is greater than the seat pressure threshold, if it is determined to be yes, proceed to step S23; if it is determined to be no, repeat step S21.

[0049] S23, start the air pump to inflate the airbag.

[0050] S24, determine whether the real-time pressure value is greater than or equal to the comfortable pressure threshold. If it is determined to be yes, proceed to step S25; if it is determined to be no, repeat step S23.

[0051] S25: The air pump stops inflating and is locked.

[0052] S26, read the capacitance sensor value and calculate the real-time pressure value. The specific formula is the same as step S21.

[0053] S27: Determine whether the real-time pressure value minus the support strength threshold is greater than the comfort pressure threshold. If so, perform the airbag exhaust function; if not, proceed to step S28.

[0054] S28, determine whether the real-time pressure value plus the tracking sensitivity threshold is less than the comfortable pressure threshold. If it is determined to be yes, perform the airbag inflation function, if not, proceed to step S29.

[0055] S29, switch to the hold state, keep the airbag inflated, and return to step S26.

[0056] Step S21, calculating the capacitance of the capacitor, the calculation formula is as follows: C represents the capacitance of the capacitor, "ε" represents the dielectric constant, "S" represents the area covered by the electrode layer and the ground electrode layer 2, "d" represents the distance between the electrode layer and the ground electrode layer 2, "π" is the circumference, and "k" is the electrostatic constant. The pressure value is calculated by the change in capacitance.

[0057] The airbag exhaust function in step S27 includes the following steps: S41, exhausting the airbag. S42, judging whether the real-time pressure is less than the comfortable pressure threshold. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S43. S43, judging whether the airbag is empty. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S41.

[0058] The airbag inflation function in step S28 includes the following steps: S31, start the air pump to inflate the airbag. S32, determine whether the real-time pressure value is greater than or equal to the comfortable pressure threshold. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S33. S33, determine whether the airbag is full. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S31.

[0059] The pressure threshold for maintaining the state in step S29 is provided with a static mode and a dynamic mode. In the static mode, the comfortable pressure threshold is lowered and the tracking sensitivity threshold is increased; in the dynamic mode, the comfortable pressure threshold is increased and the sensitivity threshold is lowered.

[0060] The present invention eliminates the influence of the human body as an electrode on the capacitive sensor, and the sensor can accurately detect the pressure between the human body and the seat. After the passenger sits down, based on the detection of the sensor, the capacitive sensing system senses the change in the distance 2 between the electrode layer 3 and the ground electrode layer, and feeds back the pressure change between the human body and the seat in real time, calculates the real-time capacitance value and pressure value, and controls the corresponding air valve to inflate or deflate until the preset pressure or the pressure set by the passenger is reached. Automatically inflate and deflate according to the posture of the human body to maintain a constant pressure between the seat support and the human body.

[0061] Embodiment 2

[0062] like Figure 2 , an adaptive capacitive sensor, other features are the same as those of the first embodiment, except that: multiple capacitive sensors are vertically arranged in the seat, multiple capacitors share a whole surface of dielectric layer 1, adhesive layer 2 4 and ground electrode layer 2, and electrode layer 3 and adhesive layer 1 5 of multiple capacitors are provided with a certain spacing. The area of ​​ground electrode layer 2 is larger than that of electrode layer 3, and the area of ​​dielectric layer 1 is larger than that of electrode layer 3 and ground electrode layer 2.

Claims

1. An adaptive capacitive sensor, comprising a seat and a capacitive sensor, characterized in that: One or more capacitive sensors are arranged in the seat, and the capacitive sensors are stacked in order from far to near the human body, including an electrode layer (3), an adhesive layer 1 (5), a dielectric layer (1), an adhesive layer 2 (4) and a grounding electrode layer (2), a capacitor is formed between the electrode layer (3) and the grounding electrode layer (2), and the grounding electrode layer (2) is grounded.

2. The adaptive capacitive sensor according to claim 1, characterized in that: The dielectric layer (1) is made of elastic material.

3. The adaptive capacitive sensor according to claim 1, characterized in that: The area of ​​the dielectric layer (1) is greater than or equal to the area of ​​the electrode layer (3) and the area of ​​the grounding electrode layer (2).

4. The adaptive capacitive sensor according to claim 1, characterized in that: The area of ​​the grounding electrode layer (2) is larger than the area of ​​the electrode layer (3).

5. The adaptive capacitive sensor according to claim 1, characterized in that: The electrode layer (3) and the grounding electrode layer (2) are provided with electrode pins (6), and the electrode pins (6) of the grounding electrode layer (2) are gathered into a main pin (7).

6. The method for adjusting the adaptive capacitive sensor according to any one of claims 1 to 5, comprising the following steps: S1. Different acceleration values ​​and bump force values ​​of the vehicle are obtained according to different road conditions to generate different pressure values, and a comfortable pressure threshold is preset; The support strength threshold is preset according to the pressure value changed by the movement of the human body caused by the bumps of the vehicle; The tracking sensitivity threshold is preset according to the pressure value reduced by tracking the inflation triggered by the human body leaving the seat; the seat occupation pressure threshold is preset according to the pressure value generated by different groups of people occupying the seat. S2. Read the seat occupancy sensor to determine whether the seat is occupied. If so, start the adaptive function; if not, do not start the adaptive function. The step adaptive function comprises the following steps: S21, read the capacitance sensor value and calculate the real-time pressure value. S22, determine whether the real-time pressure value is greater than the occupied seat pressure threshold, if it is determined to be yes, proceed to step S23; if it is determined to be no, repeat step S21. S23, start the air pump to inflate the airbag. S24, determine whether the real-time pressure value is greater than or equal to the comfortable pressure threshold. If it is determined to be yes, proceed to step S25; if it is determined to be no, repeat step S23. S25: The air pump stops inflating and is locked. S26, read the capacitance sensor value and calculate the real-time pressure value. The specific formula is the same as step S21. S27: Determine whether the real-time pressure value minus the support strength threshold is greater than the comfort pressure threshold. If so, perform the airbag exhaust function; if not, proceed to step S28. S28, determine whether the real-time pressure value plus the tracking sensitivity threshold is less than the comfortable pressure threshold. If it is determined to be yes, perform the airbag inflation function, if not, proceed to step S29. S29, switch to the hold state, keep the airbag inflated, and return to step S26.

7. The adaptive capacitive sensor and the adjustment method thereof according to claim 6, characterized in that: In step S21, the capacitance of the capacitor is calculated using the following formula: C represents the capacitance of the capacitor, "ε" represents the dielectric constant, "S" represents the area covered by the electrode layer and the ground electrode layer 2, "d" represents the distance between the electrode layer (3) and the ground electrode layer (2), "π" is the circumference, and "k" is the electrostatic constant. The pressure value is calculated from the change in capacitance.

8. The adaptive capacitive sensor and the adjustment method thereof according to claim 6, characterized in that: The airbag exhaust function in step S27 includes the following steps: S41, exhausting the airbag. S42, judging whether the real-time pressure is equal to the comfortable pressure threshold. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S43. S43, judging whether the airbag is empty. If the judgment is yes, proceed to step S29, if the judgment is no, proceed to step S41.

9. The adaptive capacitive sensor and the adjustment method thereof according to claim 6, characterized in that: The airbag inflation function in step S28 is: The method comprises the following steps: S31, starting the air pump to inflate the airbag. S32, judging whether the real-time pressure value is greater than or equal to the comfortable pressure threshold. If the judgment is yes, proceed to step S29; if the judgment is no, proceed to step S33. S33, judging whether the airbag is full. If the judgment is yes, proceed to step S29; if the judgment is no, proceed to step S31.

10. The adaptive capacitive sensor and the adjustment method thereof according to claim 6, characterized in that: The pressure threshold for maintaining the state in step S29 is provided with a static mode and a dynamic mode. In the static mode, the comfortable pressure threshold is lowered and the tracking sensitivity threshold is increased; in the dynamic mode, the comfortable pressure threshold is increased and the sensitivity threshold is lowered.

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