CN114327054A - Gesture recognition device based on FDC2214 - Google Patents
Gesture recognition device based on FDC2214 Download PDFInfo
- Publication number
- CN114327054A CN114327054A CN202111593574.0A CN202111593574A CN114327054A CN 114327054 A CN114327054 A CN 114327054A CN 202111593574 A CN202111593574 A CN 202111593574A CN 114327054 A CN114327054 A CN 114327054A
- Authority
- CN
- China
- Prior art keywords
- mode
- gesture recognition
- fdc
- main control
- control unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001514 detection method Methods 0.000 claims description 19
- 239000004973 liquid crystal related substance Substances 0.000 claims description 16
- 239000011159 matrix material Substances 0.000 claims description 14
- 238000012549 training Methods 0.000 claims description 12
- 230000004044 response Effects 0.000 claims description 11
- 238000001914 filtration Methods 0.000 claims description 7
- 238000004080 punching Methods 0.000 claims description 4
- 230000008054 signal transmission Effects 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 230000006386 memory function Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 description 10
- 108091022873 acetoacetate decarboxylase Proteins 0.000 description 7
- 230000003993 interaction Effects 0.000 description 6
- 241000282414 Homo sapiens Species 0.000 description 5
- 230000008859 change Effects 0.000 description 5
- 230000000875 corresponding effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000005070 sampling Methods 0.000 description 4
- 230000007613 environmental effect Effects 0.000 description 3
- 239000004744 fabric Substances 0.000 description 3
- 230000006698 induction Effects 0.000 description 3
- 239000004575 stone Substances 0.000 description 3
- 238000012937 correction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000001960 triggered effect Effects 0.000 description 2
- 101710096655 Probable acetoacetate decarboxylase 1 Proteins 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 210000000988 bone and bone Anatomy 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
Images
Landscapes
- User Interface Of Digital Computer (AREA)
- Position Input By Displaying (AREA)
Abstract
The invention relates to the technical field of gesture recognition, and discloses a gesture recognition device based on FDC 2214. The system detects through the capacitance sensing plane and FDC2214 and outputs to the single chip microcomputer, and converts into frequency through a specific formula, and finally, the action is judged through the difference value analysis with the initial frequency. The whole system has the functions of learning and manual calibration, can accurately and quickly judge the action in a certain range, and can realize the function of controlling the LED small lamp and the LCD screen through gestures by the control of a single chip microcomputer.
Description
Technical Field
The invention relates to the technical field of gesture recognition, in particular to a gesture recognition device based on FDC 2214.
Background
Human Computer Interaction (HCI) is of self-evident importance in people's work and life. Achieving natural human-to-human interaction with a work system is a basic goal of human-to-computer interaction, wherein gestures are one of the most basic features of human beings, are one of the easiest and most convenient control ways of human beings, and are always considered to be a more natural, creative and intuitive interaction means for communicating with our computers. The application of the gesture recognition system in daily life is more and more extensive, and particularly, the market application prospect of the gesture recognition system is more and more extensive due to the continuous development of the era of the internet of things.
Due to the complexity and changeability and the great significance of gestures, the method not only relates to cultural traditions in different regions, but also designs the difference of personal habits, and has the characteristics of complex human bone structure of human hands and low recognition rate of a gesture recognition system, so that the method becomes a research subject of interdisciplinary study. In modern society, people pay more and more attention to convenience of human-computer interaction and attractive portability of human-computer interaction equipment, research on gesture recognition systems follows up with development trend, and certain achievements have been achieved in many fields, but still many problems which cannot be solved exist, such as: the gesture recognition system is inconvenient to miniaturize, high in cost, complex in programming and the like, and has extremely important significance for solving the existing problems through research and development of the gesture recognition system.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides a gesture recognition device based on an FDC 2214. The specific technical scheme is as follows:
the utility model provides a gesture recognition device based on FDC2214, includes C8051F020 main control unit, FDC2214 capacitive sensing chip, TFT liquid crystal display and electric capacity sensing plane, uses C8051F020 main control unit as control core, uses FDC2214 capacitive sensing chip as data acquisition unit, and TFT liquid crystal display is display module, uses six blocks of capacitive sensing planes as induction panel, C8051F020 main control unit is as MCU control core, and it is equipped with the LED charactron and is used for showing the induction value, is furnished with LED status indicator simultaneously and is used for the status indication, is furnished with the key matrix and is used for setting up different detection mode, TFT liquid crystal display is used for showing state information and makes the different responses of gesture to the difference.
Furthermore, the C8051F020 main control unit is connected with the LED nixie tube, the LED state display lamp and the key matrix by utilizing a printed circuit board manufacturing process, and the C8051F020 main control unit is connected with the TFT liquid crystal display and the FDC2214 capacitive sensing chip by utilizing a DuPont wire through an IO pin LED out by the ADC detection unit.
Further, after the led-out IO pin is configured to be in an ADC detection mode, the FDC2214 capacitive sensing chip and the six capacitive sensing planes are uniformly welded and connected by using six voltage signal transmission lines, and voltage signals are collected and filtered by using a digital filtering algorithm to output a corresponding judgment result.
Further, the C8051F020 main control unit is used as an MCU control core, the peripheral IO port is set to an ADC detection mode, a driver chip is provided for driving the LED nixie tube, the IO port is configured to a push-pull output mode for the LED status indicator, the IO port is configured to an input mode for the key matrix, and a TFT liquid crystal display screen driven by the ILI 9341-based driver is provided for displaying status information and making different responses for different gestures.
Further, the key matrix may be used for configuration of different modes, which includes: the training mode, the gesture judging mode, the gesture control mode, the finger guessing game mode and the punching game mode with the self-adaptive memory function.
Furthermore, the capacitance sensing plane is connected by six copper-clad conducting layers and two transparent insulating cover plates through a fixed shaft, and each copper-clad conducting layer is divided by an insulating dividing layer.
Compared with the prior art, the invention has the following beneficial effects:
six capacitive sensing planes are used as sensing panels to replace 1 capacitive sensing plane on the market, in the aspects of data acquisition and subsequent data processing, in order to eliminate pulse interference in accidental errors, a mode of combining a median filtering method with an amplitude limiting filtering method is selected, in order to eliminate environmental fixed errors, the gesture recognition system based on the FDC2214 selects 100 sampling points in a training mode, and obtains a relatively stable value by taking an average mode after removing the maximum value and the minimum value, and the value obtained by subtracting the two numbers is used as a correction factor, so that errors caused by environmental factors can be effectively removed. The controller adopts a C8051F020 main control unit with low cost and high performance, and the capacitance detection chip adopts a novel capacitance detection chip FDC2214 with low power consumption and high recognition rate. Compared with the method for single-channel detection by using the MS3110 capacitance detection chip based on STM32, DSP and other controllers in the prior art, the method reduces the cost and improves the identification precision and the real-time property.
Drawings
FIG. 1 is a system diagram of an FDC 2214-based gesture recognition apparatus according to the present invention;
FIG. 2 is a functional block diagram of an FDC 2214-based gesture recognition apparatus according to the present invention;
FIG. 3 is a schematic diagram of an FDC2214 non-contact capacitive sensor of an FDC 2214-based gesture recognition apparatus of the present invention;
FIG. 4 is a flow chart of a FDC 2214-based gesture recognition method of the present invention;
FIG. 5 is a flowchart of a gesture control mode subroutine of the FDC 2214-based gesture recognition apparatus according to the present invention;
FIG. 6 is a block diagram of a functional circuit of a C8051F020 main control unit ADC0 of the FDC 2214-based gesture recognition device of the present invention;
in the figure: the device comprises a 1-TFT liquid crystal display screen, a 2-LED nixie tube, a 3-FDC2214 capacitive sensing chip, a 4-capacitive sensing plane, a 5-LED state indicator lamp, a 6-key matrix, a 7-C8051F020 main control unit, an 8-ADC detection unit, a 9-DuPont wire, a 10-voltage signal transmission line, an 11-transparent insulating cover plate, a 12-fixed shaft, a 13-copper-coated conducting layer and a 14-insulating partition layer.
Detailed Description
The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art.
As shown in fig. 1-6, the FDC 2214-based gesture recognition apparatus of the present invention uses a C8051F020 main control unit 7 as a control core, an FDC2214 capacitive sensing chip 3 as a data acquisition unit, a TFT liquid crystal display 1 as a display module, and six capacitive sensing planes 4 as sensing panels. The C8051F020 main control unit 7 is used as an MCU control core, is provided with an LED nixie tube 2 for displaying induction numerical values, is provided with an LED state indicator lamp 5 for state indication, is provided with a key matrix 6 for setting different detection modes, and is provided with a TFT liquid crystal display screen 1 driven by an ILI9341 driver for displaying state information and making different responses aiming at different gestures. The C8051F020 main control unit 7 is connected with the LED nixie tube 2, the LED state display lamp 5 and the key matrix 6 by utilizing a printed circuit board manufacturing process, and the C8051F020 main control unit 7 is connected with the IO pin LED out by the ADC detection unit 8 by utilizing a DuPont wire 9 through the TFT liquid crystal display screen 1 and the FDC2214 capacitive sensing chip 3. After the lead-out IO pins are configured into an ADC detection mode, the FDC2214 capacitive sensing chip 3 and the six capacitive sensing planes 4 are uniformly welded and connected by using six voltage signal transmission lines 10, and voltage signals are collected and filtered by using a digital filtering algorithm to output corresponding judgment results.
The C8051F020 main control unit 7 is used as an MCU control core, an external IO port is set to be in an ADC detection mode, a driving chip is arranged for driving the LED nixie tube 2, the IO port is configured to be in a push-pull output mode for the LED state indicator lamp 5, the IO port is configured to be in an input mode for the key matrix 6, and the TFT liquid crystal display screen 1 driven by the ILI 9341-based driver is configured to display state information and make different responses aiming at different gestures, wherein the responses refer to screen cutting, horse race lamps, love heart drawing and the like.
Wherein the key matrix 6 can be used for configuration of different modes, here said different modes comprising: the training mode, the gesture judging mode, the gesture control mode, the finger guessing game mode and the punching game mode with the self-adaptive memory function. The response mode mainly comprises the change of the states of the marquee and the TFT liquid crystal display screen 1, response signals can be transmitted to the control terminal in a wired/wireless mode, and then corresponding actions are executed, wherein the control terminal is hardware equipment such as a mobile phone, a notebook computer and the like.
The capacitance sensing plane 4 is connected by six copper-clad conductive layers 13 and two transparent insulating cover plates 11 through a fixed shaft 12, and in order to ensure that the six copper-clad conductive layers 13 are not connected, the copper-clad conductive layers are divided by superfine insulating dividing layers 14.
The working process is as follows:
as shown in fig. 6, the C8051F020 main control unit 7 is equipped with two analog-to-digital converters, ADC0 and ADC 1. The ADC0 is a 12-bit analog-to-digital converter with a sampling speed of 100ksps, and the accuracy and sampling speed are sufficient for the system. In use, when the AD0EN enable bit is set to "1", the on-chip ADC0 is allowed to perform acquisition conversion operation, otherwise the ADC0 operates in the low power consumption shutdown mode. The calculation formula is as follows, assuming that the analog input signal is V, the digital output is D, and the reference voltage is VREF, since the ADC is 12 bits, the range of the digital output D is 0 to 4095, the relationship between the digital output D and the analog input V is:
a block diagram of the functional circuit of the ADC0 is shown in fig. 6.
As shown in fig. 3, each FDC2214 capacitive sensor chip 3 includes 2 detection input channels, and a capacitor and an inductor are connected to an input end of each channel to form an LC oscillating circuit. The measured capacitance in fig. 3 is connected to an LC oscillator circuit to generate an oscillation frequency fs and transmit the data to the Core. Core and reference frequency fREFComparing to obtain a result, will
Is set to D, and the resulting capacitance value is calculated by the following formula. Then the voltage is converted into voltage by an external circuit, and the voltage is sent into a self-contained AD converter of C8051F020 through an I2C interface to be converted into a numerical value.
The measured frequency value can be obtained according to the following formula:
according to fsThe capacitance value to be measured is calculated by the following formula:
wherein, L and C are respectively the inductance and capacitance connected with the input end.
The gesture can be judged by detecting the capacitance and frequency change when the hand approaches the sensing interface of the copper-clad plate.
In view of the principle that the FDC2214 capacitive sensing chip realizes capacitive sensing detection and can be known by referring to a data manual, the FDC2214 capacitive sensing chip has the following characteristics: the larger the area of the sensing plane and the lower the gesture placement position are, the larger the detected frequency change is, but the more environmental noise is introduced by the effect of the change.
In addition, because the system response speed requirement is high, the requirements of high precision and low time delay are required to be met simultaneously, errors which mainly exist in the system can be accidental errors and environment fixed errors, and the parameter measurement change speed is low, therefore, the gesture recognition device based on the FDC2214 selects a mode of combining a median filtering method and an amplitude limiting filtering method in the aspect of eliminating the accidental errors, the pulse interference caused by accidental factors can be effectively overcome, and the system stability is improved. In the aspect of environment fixed error, the invention selects 100 sampling points in a training mode, removes the maximum value and the minimum value, and then takes an average mode to obtain a relatively stable value, and takes the value of the difference between the two numbers as a correction factor, thereby effectively removing the error caused by environment factors.
As shown in fig. 4, the "training mode" is entered after pressing "10" of the key matrix 6. In this mode, the system performs input learning of various gestures. According to the characteristics of the FDC2214 capacitive sensing chip, different gestures have different areas on the sensor, so that different capacitance values and corresponding oscillation frequency values are obtained, the maximum value and the minimum value of the data are removed, and the average value is taken as a judgment standard. The tester must make corresponding gesture in the specified sensing plane according to the suggestion content in the LCD display screen, and sensing device gathers tester's training data, and every gesture can automatic acquisition 3 times, gets the average and saves in the singlechip for follow-up comparison.
The "gesture determination mode" is entered after the key "11" is pressed. In the mode, the system defaults to a punching mode, namely, a tester can randomly make gestures of '1', '2', '3', '4' and '5' in a specified sensing plane, the system compares detected data with stored data in a 'training mode', and a judgment result is displayed in an LCD screen; when the tester presses the key 15, the system is changed into a finger-guessing mode, the tester can randomly make gestures 'stone', 'scissors' and 'cloth' in a specified sensing plane, the system compares the detected data with the stored data in the 'training mode', and the judgment result is displayed in the LCD screen. The mode can be matched with a learning result of a training mode system to correct, the accuracy of the system can be effectively improved, when the device is placed for too long time, the copper-clad plate can be corroded, the mode can be adopted for calibration, and the stability of the system is improved
The "gesture control mode" is entered after pressing the key "12". In this mode, the tester can show different gestures in the designated sensing plane, the system performs certain control on the system after detection and determination, for example, a horse race lamp is triggered when the system determines that the gesture is "stone", and an LCD screen switching operation is triggered when the system determines that the gesture is "cloth", and the flowchart is shown in FIG. 5.
The "guessing boxing match mode" is entered after the key "14" is pressed. In this mode, two testers respectively draw gestures "stone", "scissors" and "cloth" on two designated copper-clad plate sensing planes. Wherein each gesture made by the tester should be the same as the gesture recorded by the system in the training mode. The system will make a game decision in no more than 1 second and display it on the LCD screen.
The "punch match mode" is entered after the key "15" is pressed. In this mode, two testers gesture "1", "2", "3", "4", "5" at two designated sensing planes, respectively. Wherein each gesture made by the tester should be the same as the gesture recorded by the system in the training mode. The system will make a game decision in no more than 1 second and display it on the LCD screen. And (4) judging the standard: "5" > "4", "4" > "3", "3" > "2", "2" > "1", and "1" > "5".
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (6)
1. An FDC 2214-based gesture recognition device comprises a C8051F020 main control unit (7), an FDC2214 capacitive sensing chip (3), a TFT liquid crystal display screen (1) and a capacitive sensing plane (4), and is characterized in that: use C8051F020 main control unit (7) as control core, regard FDC2214 capacitive sensing chip (3) as data acquisition unit, TFT liquid crystal display (1) is display module, regard as sensing panel with six electric capacity sensing planes (4), C8051F020 main control unit (7) are as MCU control core, and it is equipped with LED charactron (2) and is used for showing the response numerical value, is furnished with LED status indicator lamp (5) simultaneously and is used for status indication, is furnished with key matrix (6) and is used for setting up different detection mode, TFT liquid crystal display (1) are used for showing status information and make different responses to different gestures.
2. The FDC 2214-based gesture recognition apparatus of claim 1, wherein: C8051F020 main control unit (7) and LED charactron (2), LED state display lamp (5), button matrix (6) utilize printed circuit board manufacturing process to be connected, the IO pin that C8051F020 main control unit (7) and TFT liquid crystal display (1), FDC2214 capacitive sensing chip (3) adopt ADC detecting element (8) to draw utilizes dupont line (9) to connect.
3. The FDC 2214-based gesture recognition apparatus of claim 2, wherein: after the lead-out IO pins are configured into an ADC detection mode, the FDC2214 capacitive sensing chip (3) and the six capacitive sensing planes (4) are uniformly welded and connected through six voltage signal transmission lines (10), and voltage signals are collected and filtered by a digital filtering algorithm to output corresponding judgment results.
4. The FDC 2214-based gesture recognition apparatus of claim 2, wherein: the C8051F020 main control unit (7) is used as an MCU control core, an external IO port is set to be in an ADC detection mode, a driving chip is arranged for driving the LED nixie tube (2), the IO port is configured to be in a push-pull output mode for the LED status indicator lamp (5), the IO port is configured to be in an input mode for the key matrix (6), and the TFT liquid crystal display screen (1) driven by the ILI9341 driver is configured to display status information and make different responses aiming at different gestures.
5. The FDC 2214-based gesture recognition apparatus of claim 1, wherein: the key matrix (6) can be used for different modes of configuration, including: the training mode, the gesture judging mode, the gesture control mode, the finger guessing game mode and the punching game mode with the self-adaptive memory function.
6. The FDC 2214-based gesture recognition apparatus of claim 1, wherein: the capacitance sensing plane (4) is formed by connecting six copper-clad conductive layers (13) and two transparent insulating cover plates (11) through a fixed shaft (12), and each copper-clad conductive layer is divided by an insulating dividing layer (14).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111593574.0A CN114327054A (en) | 2021-12-21 | 2021-12-21 | Gesture recognition device based on FDC2214 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111593574.0A CN114327054A (en) | 2021-12-21 | 2021-12-21 | Gesture recognition device based on FDC2214 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114327054A true CN114327054A (en) | 2022-04-12 |
Family
ID=81055556
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111593574.0A Pending CN114327054A (en) | 2021-12-21 | 2021-12-21 | Gesture recognition device based on FDC2214 |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114327054A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109241876A (en) * | 2018-08-20 | 2019-01-18 | 苏州大学 | A kind of gesture recognition system and method based on k nearest neighbor algorithm |
| CN109343422A (en) * | 2018-09-07 | 2019-02-15 | 浙江理工大学 | A kind of automatic lifting table gesture identification and position regulator |
| CN110275614A (en) * | 2019-05-30 | 2019-09-24 | 福建工程学院 | A kind of non-contact gesture identification device and its method |
-
2021
- 2021-12-21 CN CN202111593574.0A patent/CN114327054A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109241876A (en) * | 2018-08-20 | 2019-01-18 | 苏州大学 | A kind of gesture recognition system and method based on k nearest neighbor algorithm |
| CN109343422A (en) * | 2018-09-07 | 2019-02-15 | 浙江理工大学 | A kind of automatic lifting table gesture identification and position regulator |
| CN110275614A (en) * | 2019-05-30 | 2019-09-24 | 福建工程学院 | A kind of non-contact gesture identification device and its method |
Non-Patent Citations (2)
| Title |
|---|
| 于燕秀 等: "基于FDC2214的非接触式手势识别装置", 工业技术创新, vol. 05, no. 05, 25 October 2018 (2018-10-25), pages 76 - 81 * |
| 张辉 等: "基于FDC2214电容传感器的手势识别装置的设计与实现", 巢湖学院学报, vol. 20, no. 6, 25 November 2018 (2018-11-25), pages 84 - 90 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104679367B (en) | Sender unit and its control method | |
| CN102004126A (en) | Electrochemical biosensor and detecting method thereof | |
| CN110658241A (en) | Multiple gas detection device | |
| CN107102773A (en) | A kind of Touch-control error prevention method, terminal and computer-readable recording medium | |
| CN203758766U (en) | Cardiopulmonary resuscitation machine detection device | |
| CN206399476U (en) | A kind of water analysis circuit | |
| CN202870789U (en) | Remote control | |
| CN114487784A (en) | Capacitance detection circuit, touch chip and electronic equipment | |
| CN211978749U (en) | Multiple gas detection device | |
| CN204302672U (en) | A kind of intelligent watch | |
| CN114327054A (en) | Gesture recognition device based on FDC2214 | |
| CN206369726U (en) | A kind of Intelligent monitoring device with NB IOT gas collecting functions | |
| CN201594148U (en) | Environment detection device | |
| CN217085101U (en) | Capacitance detection circuit, touch control chip and electronic equipment | |
| CN216290869U (en) | Multifunctional remote controller capable of being wakened up by hand-holding induction | |
| CN203241128U (en) | Multifunctional body scale | |
| CN201724923U (en) | Electrochemical biosensor | |
| CN1181320C (en) | Multiple-parameter vibration measuring pen | |
| CN204143375U (en) | A kind of multifunctional intellectual wrist strap | |
| CN104720789A (en) | Electrocardio measuring instrument with single switch and measuring method | |
| EP3338165A1 (en) | Universal contactless gesture control system | |
| US20080266260A1 (en) | Apparatus Having Handwriting and Mouse Input Functions | |
| CN202330439U (en) | Blood-glucose detection device and blood-glucose detection system | |
| CN101150311A (en) | A simplified circuit for touch control | |
| CN204468077U (en) | Single switch cardiographic detector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |