Circumferential array type capacitive proximity sensor based on sector ring structure

Abstract

The invention discloses a circumferential array type capacitive proximity sensor based on a fan-shaped ring structure. The circumferential array type capacitive proximity sensor comprises a fan-shaped capacitor structure, an electronic measurement system and signal acquisition and processing software, the fan-shaped capacitor structure is connected with the electronic measurement system through a communication line, and the signal acquisition and processing software is connected with the electronic measurement system through a communication line. The fan-shaped capacitor structure is composed of a mechanical capacitor structure formed by a single electrode array, the fan-shaped capacitor structure comprises 12 electrode units, each electrode unit is a fan-shaped annular plate capacitor, and the fan-shaped annular plate capacitors are arranged at equal angles according to a circumferential array. According to the invention, signal acquisition and processing software design is carried out, and visualization and storability of capacitance value, distance information and angle information of the capacitive proximity sensor are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and particularly relates to a circular array capacitive proximity sensor based on a sector ring structure. Background Art

[0002] With the rapid development of modern industry, automation, and robotics technologies, sensors, as an indispensable component in these fields, are playing an increasingly important role. Sensors are used to detect, measure, and record various physical quantities, thereby achieving environmental perception and information transmission. Among them, proximity sensors have been widely used in many fields such as industrial automation, security monitoring, and smart homes because they can detect the proximity or presence of objects non-contactingly.

[0003] Capacitive proximity sensors are an important type of proximity sensors, and their working principle is based on the change in capacitance to detect the proximity of objects. Specifically, when the object to be measured approaches the sensing surface of the capacitive proximity sensor, due to the formation of mutual capacitance between the object and the sensor, the capacitance value of the sensor also changes accordingly. This change in capacitance value can be converted into an electrical signal output through a circuit, thereby achieving the detection of the proximity of the object.

[0004] In the past few decades, capacitive proximity sensor technology has been continuously improved and optimized. On the one hand, with the progress of materials science, new types of sensing electrode materials and dielectric materials have been applied to capacitive proximity sensors, improving the sensitivity and stability of the sensors. On the other hand, with the development of microelectronics technology and signal processing technology, the circuit design and signal processing capabilities of capacitive proximity sensors have also been significantly improved, enabling the sensors to detect the proximity of objects more accurately and work stably in complex environments. However, despite the significant progress made in capacitive proximity sensor technology, there are still some challenges and problems. For example, existing capacitive proximity sensors cannot detect the distance to the approaching object in real time and cannot detect the approaching angle of the object. Summary of the Invention

[0005] Aiming at the defects existing in the prior art, the purpose of the present invention is to achieve real-time detection of the distance to the approaching object and detection of the approaching angle of the object. The technical solution adopted by the present invention is as follows:

[0006] A circular array capacitive proximity sensor based on a sector ring structure, the sensor comprising:

[0007] A sector capacitor structure, an electronic measurement system, and signal acquisition and processing software; the sector capacitor structure is connected to the electronic measurement system through a communication line, and the signal acquisition and processing software and the electronic measurement system are connected through a communication line.

[0008] Among them, the sector capacitor structure is composed of a mechanical capacitor structure formed by a single electrode array. Specifically, the sector capacitor structure includes 12 electrode units, and each electrode unit is a sector-shaped flat capacitor. These sector-shaped flat capacitors are arranged at equal angles in a circular array; each electrode unit (i.e., the sector-shaped flat capacitor) has the following characteristics:

[0009] (1) The shapes of the upper and lower electrode plates are sector rings and are of equal size.

[0010] (2) The total angle covered by each electrode unit is 30°, including 28° of sector copper foil plus 1° of sector gaps on both sides, ensuring that all electrode units in the circular array can completely cover the entire circumference of 360° without interference.

[0011] (3) The inner radius of the sector copper foil is 12 mm and the outer radius is 30 mm, thus forming an annular region with a width of 18 mm.

[0012] The sector-shaped flat capacitors are arranged in an equally divided circular array with a straight line passing through the center of the sector ring and perpendicular to the plane where the flat capacitor is located as the axis. Since each electrode unit and its gap altogether occupy an angle of 30°, 12 such electrode units can be arranged at equal intervals on the circumference, ensuring that the angles between each electrode unit are equal, all being 30°. This layout ensures the uniform distribution of the electrode units on the circumference, and their extension lines intersect at one point, that is, the center of the circle. To sum up, this structure designs a circular array composed of 12 sector-shaped flat capacitors of the same size. Each capacitor unit covers a circumferential angle of 30°, including a 28° effective capacitance region and a 2° gap. The upper and lower electrode plates are of equal size, with an inner radius of 12 mm and an outer radius of 30 mm. This structure realizes high-precision detection of approaching objects through an equal-angle and uniform distribution method.

[0013] The electronic measurement system includes: a capacitance detection chip, a microprocessor MCU, and a communication chip. Among them,

[0014] The capacitance detection chip is connected to the sector-shaped flat capacitor and also connected to the microprocessor MCU for converting the analog capacitance value into a digital capacitance value. The microprocessor MCU is connected to the capacitance detection chip and the communication chip for configuring with the capacitance detection chip, reading data, and performing preliminary data decoding. The communication chip is connected to the microprocessor MCU and the communication line for sending the decoded capacitance value to the signal acquisition and processing software.

[0015] The signal acquisition and processing software and the electronic measurement system are connected through a communication line.

[0016] Preferably, the preparation process of the mechanical capacitor structure includes PCB process, soft lithography / soft etching technology, and polymer molding technology.

[0017] Preferably, the capacitance detection chip models include MDC04, FDC1004, and AD7147, the microprocessor MCU model includes STM32RCT6, and the communication chip includes CP2102-GMR.

[0018] Preferably, the signal acquisition and processing software transfers data with the electronic system through the USB communication protocol, and can store the acquired and processed data, and visually display it on the display in the form of charts such as line charts and bar charts.

[0019] To achieve the above object, the working process of a capacitive proximity sensor based on a fan-shaped structure is as follows:

[0020] (1) When a hand or finger approaches the fan-shaped mechanical structure of the sensor, the capacitance values of the capacitors in the array change;

[0021] (2) The capacitance detection chip detects the change in the capacitance value, converts the capacitance value into a digital signal, the microprocessor MCU communicates with the capacitance detection chip, obtains the digital information in its register, and sends the digital information to the signal acquisition and processing software through the communication chip;

[0022] (3) The signal acquisition and processing software receives the digital signal related to the capacitance value, performs digital filtering, classification, and sorting, then visually presents it on the display, and saves the acquired original information.

[0023] Based on the above technical solutions, compared with the prior art, the advantages of the present invention are as follows: The array of fan-shaped flat capacitors is carried out, the capacitance detection chip, microprocessor MCU, and communication chip are used to digitize the capacitance value, and the signal acquisition and processing software is designed, making it possible for the capacitive proximity sensor to visualize and store the capacitance value, distance information, and angle information. Description of the Drawings

[0024] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] By reading the detailed description of the non-restrictive embodiments with reference to the following drawings, other features, objects, and advantages of the present application will become more obvious:

[0026] Figure 1The system block diagram and capacitive mechanical structure diagram of a capacitive proximity sensor based on a fan-shaped structure showing an embodiment of the present application;

[0027] Figure 2 The electronic measurement system block diagram of a capacitive proximity sensor based on a fan-shaped structure showing an alternative embodiment of the present application;

[0028] Figure 3 It is a schematic flow diagram of the electronic measurement system and the signal acquisition and processing software. Detailed implementation manners

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0030] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] As Figure 1 The block diagram and fan-shaped capacitance structure diagram of a capacitive proximity sensor based on a fan-shaped structure showing an embodiment of the present application, wherein the sensor 1 includes:

[0032] A fan-shaped capacitance structure 11, an electronic measurement system 12, and a signal acquisition and processing software 13, wherein,

[0033] The fan-shaped capacitance structure 11 refers to a mechanical capacitance structure formed by a single electrode array. The single electrode type refers to a fan-shaped flat capacitor. The sizes of the upper and lower plates of the fan-shaped flat capacitor are equal. The array means that a single fan-shaped ring electrode is equally divided into a circular array with a straight line passing through the center of the fan-shaped ring and perpendicular to the plane where the flat capacitor is located as the axis. The equal division means that the angles between each single electrode are equal, and this angle is a divisor of 360. Due to the adoption of the fan-shaped flat capacitor design and combined with the arrangement method of the circular array, by measuring the change in capacitance, the direction and distance of the approaching object can be accurately sensed and measured. Since the capacitive mechanical structure is integrated on the PCB board, the possibility of the capacitive connection wires of the CDC chip being interfered by the outside is reduced. This design enables the sensor to maintain stable performance in a complex environment, improves the measurement accuracy, and can achieve high-precision capacitance measurement.

[0034] As Figure 2 The electronic measurement system block diagram of a capacitive proximity sensor based on a fan-shaped structure showing an alternative embodiment of the present application, wherein the electronic measurement system 2 includes:

[0035] The electronic measurement system includes: a capacitance detection chip 22, a microprocessor MCU 21, and a communication chip 23. Among them, the capacitance detection chip 22 is connected to the microprocessor MCU, the capacitance detection chip 22 is connected to the capacitor 14, the microprocessor MCU 21 is connected to the capacitance detection chip 22, and the communication chip 23 is connected to the microprocessor MCU 21. Among some of the advantages and functions, the capacitance detection chip 22 can achieve high-precision capacitance value measurement. The system can accurately read the values of multiple capacitors, providing a reliable basis for subsequent data processing and analysis. The addition of the communication chip 23 enables the system to connect to external devices or networks through the communication chip 23 to achieve remote data transmission and monitoring, facilitating the centralized management and analysis of data. The entire system adopts a modular design, and the connections between components are stable and reliable, not easily affected by the external environment, ensuring the accuracy of measurement and the stability of the system.

[0036] Such as Figure 3 Shown is a software architecture diagram of a signal acquisition and processing software for a circular array capacitive proximity sensor based on a sector ring structure according to an optional embodiment of the present application. The signal acquisition and processing software receives the digital signal of the capacitance value sent by the electronic measurement system, filters and classifies the signal, and visualizes it on a display in the form of charts such as line charts and bar charts.

[0037] Preferably, the manufacturing process of the mechanical structure 11 includes PCB process, soft lithography / soft etching technology, and polymer molding technology.

[0038] Preferably, the capacitance detection chip models include MDC04, FDC1004, AD7147, the microprocessor MCU model includes STM32RCT6, and the communication chip includes CP2102-GMR.

[0039] Furthermore, the data acquisition and processing software performs data transmission with the electronic system through the USB communication protocol, and can store the acquired and processed data and visualize it on a display.

[0040] The working process of a circular array capacitive proximity sensor based on a sector ring structure is as follows:

[0041] (1) When a hand or finger approaches the sector-shaped mechanical structure 14 of the sensor, it causes the capacitance values of the capacitors in the array to change. The maximum change in capacitance is 3.18 pF, and the angular sensitivity can reach 0.02185 (pF / °), and the actual measured angular resolution is approximately 5°.

[0042] (2) The capacitance detection chip 22 detects the change in capacitance value, converts the capacitance value into a digital signal. The microprocessor MCU21 communicates with the capacitance detection chip 22 to obtain the digital information Code in its register, and decodes it through the microprocessor MCU21. The decoding formula is as follows:

[0043]

[0044] And the digital information is sent to the data acquisition and processing software through the communication chip 23.

[0045] (3) The data processing software receives the digital signal related to the capacitance value, performs digital filtering, classification and sorting, visualizes it on the display, and saves the original information collected.

[0046] It should be noted that in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0047] The above are only specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A circular array capacitive proximity sensor based on a fan ring structure, characterized in that: The sensor comprises: A fan-shaped capacitor structure (11), an electronic measurement system (12), and a signal acquisition and processing software (13); the fan-shaped capacitor structure is connected to the electronic measurement system via a communication line, and the signal acquisition and processing software is connected to the electronic measurement system via a communication line; The fan-shaped capacitor structure (11) is composed of a mechanical capacitor structure composed of a single electrode array, and the fan-shaped capacitor structure (11) includes 12 electrode units, each of which is a fan-shaped flat plate capacitor, and the fan-shaped flat plate capacitors are arranged at equal angles in a circular array.

2. The circular array capacitive proximity sensor based on the fan ring structure according to claim 1, characterized in that: The fan-shaped annular flat plate capacitor has upper and lower plates in the shape of fan-shaped rings of equal size; each electrode unit covers a total angle of 30°, including 28° of fan-shaped ring copper foil plus a fan-shaped gap of 1° on both sides; the inner radius of the fan-shaped ring copper foil is 12mm, and the outer radius is 30mm, forming an annular area with a width of 18mm.

3. The circular array capacitive proximity sensor based on the fan ring structure according to claim 2, characterized in that: The fan-shaped flat-plate capacitors are arranged in an array by equally dividing the circumference with a straight line passing through the center of the fan-shaped ring and perpendicular to the plane where the flat-plate capacitors are located as the axis.

4. The circular array capacitive proximity sensor based on the fan ring structure according to claim 3, characterized in that: The electronic measurement system includes: a capacitance detection chip, a microprocessor MCU and a communication chip; the capacitance detection chip is connected to the fan-shaped flat plate capacitor and to the microprocessor MCU, and converts the analog capacitance value into a digital capacitance value; the microprocessor MCU is connected to the capacitance detection chip and the communication chip, and is used for configuration and data reading of the capacitance detection chip and preliminary data decoding, and the communication chip sends the decoded capacitance value to the signal acquisition and processing software.

5. The circular array capacitive proximity sensor based on a fan ring structure according to claim 4, characterized in that: The signal acquisition and processing software transmits data with the electronic system through the USB communication protocol, stores the acquired and processed data, and displays them visually on the display.

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