Design and development of intelligent shoe cabinet control board

With the advent of the smart age, smart home has become an important topic and main direction for people from all walks of life to discuss and conduct in-depth research. However, there are very few smart solutions for shoe cabinets in smart homes. The existing electronic smart shoe cabinets on the market There are disadvantages such as single function and insufficient sterilization and deodorization strength for shoes. Therefore, this paper improves and strengthens the functional types, heating and dehumidification, sterilization and deodorization of the shoe cabinet.

The STM32F103RBT6 single-chip microcomputer is used as the core control processor, the external data is collected through the peripheral sensor, and the corresponding functions are realized after processing by the single-chip microcomputer.

On the one hand, this design realizes closed-loop feedback control by controlling the peripheral sensor module. On the other hand, it uses a 220V to 12V switching power supply or a solar panel to switch between these two modes, which can be directly powered by 220V or placed on a balcony, etc. Charging in places with high light intensity and large light area is not only safe and reliable, but also energy-saving and environmentally friendly.

1. The overall design scheme of the intelligent shoe cabinet system

The whole system is powered by solar panels or 220V switching power supply. The whole shoe cabinet is composed of wooden boards. The drawings are designed by SolidWorks and processed by engraving machine. There are 4 self-locking universal wheels under the shoe cabinet for easy movement. ;By using ozone generator, negative ion generator, temperature and humidity sensor, PTC heating ceramic chip, smoke alarm and other sensors for data collection, STM32F103RBT6 single-chip microcomputer is selected as the core control processor for data processing to realize closed-loop feedback control, using TFT LCD screen Display parameters, realize wireless communication through Bluetooth, and display test data on the mobile terminal to achieve expected results.

2. Hardware design of intelligent disinfection shoe cabinet system

This system is mainly composed of optocoupler isolation circuit, heating and dehumidification, disinfection, display screen and other external circuits. The power supply is powered by switching power supply or solar panel, and the data is returned in real time by Bluetooth.

2.1 Minimum system circuit of single chip microcomputer

The intelligent energy-saving shoe cabinet system uses STM32F103RBT6 as the main controller. There are three reasons for choosing this single-chip model: (1) Its powerful processing speed is much higher than that of 51 series single-chip microcomputers and MSP430 series single-chip microcomputers; (2) There are relatively many GPIO ports , which fully meets the requirement of numerous pins for our peripheral sensors; (3) In the process of programming, the overall program framework is clearer and more modular.

2.2 Power supply and optocoupler isolation circuit design

(1) Selection of solar panels and switching power supply: The solar panel adopts the 12V household monocrystalline solar panel of the photovoltaic power generation system. Monocrystalline silicon solar cells have the highest photoelectric conversion efficiency among all types of solar cells. The switching power supply adopts a finished module with an input voltage of 115~223V, an input current of 0.45~0.8A, an output voltage of -12~+12V, and an output current of 3A. The step-down circuit is designed with LM2940 chip, which can drop the 12V voltage to 5V.

(2) Optocoupler isolation circuit design: The optocoupler isolation circuit has a good isolation effect on the input and output electrical signals. The chip type used in the optocoupler circuit in this design is HCPL-2630, which can realize the isolation of two-way signals .

2.3 Temperature and humidity detection and gas concentration detection system

Temperature detection selects DS18B20 sensor, which has the advantages of low cost and low power consumption. Humidity detection uses DHT11 sensor, which is accurate in measurement, easy to operate, and low in price. The gas concentration detection uses the MQ135 sensor, which can detect the gas concentration inside the shoe cabinet in real time.

2.4 Heating and dehumidification system

The heating part uses high-efficiency and energy-saving PTC heating ceramics and cooling fans to heat and dehumidify the inside of the shoe cabinet. The PTC heating element has the advantages of small thermal resistance and high heat exchange efficiency. The ventilation fan adopts a 5V low-power chassis cooling fan, which can not only save energy but also have the effect of ventilation.

2.5 Sterilization, deodorization and dust removal system

The ozone generated by the ozone generator oxidizes and decomposes the gas components such as ammonia and methyl mercaptan contained in the odor in the shoes, so as to achieve the purpose of deodorization. The negative ions generated by the negative ion generator settle the bacteria and dust floating in the air after the shoe shine, so as to achieve the purpose of dust removal.

2.6 Display system

The display module used in this design is a 2.7-inch TFT LCD screen, which can display screen information at high speed, high brightness, and high contrast.

2.7 Wireless Transmission System

Use the HC-05 Bluetooth module to communicate with the mobile terminal, and the mobile terminal controls the shoe cabinet through the serial port assistant. This type of Bluetooth has the advantages of fast speed and simple pairing.

3. Software design of intelligent disinfection shoe cabinet system

C language is used as the code language, and the keil5 platform is used for writing and development. The program is written based on STM32F103RBT6, which has many pins and rich internal resources, and the modular programming is easy to understand. The overall solution is that the single-chip microcomputer initializes the entire system, and the temperature and humidity sensor works first. When the humidity in the cabinet is too high, the heating and dehumidification system is triggered, and the DS18B20 senses the temperature to control the stop of the heating system; when the MQ135 detects that the gas concentration in the cabinet is too high, it triggers The ozone generator module deodorizes, and then the shoe shine system is processed. The negative ion generator will settle the bacteria and dust in the air; detect the concentration of gas odor, judge the current cleanliness of the shoes, and feed back the information to the single chip microcomputer Thereby triggering the exhaust air shoe-shining module to start cleaning the shoes.

3.1 Heating and dehumidification program design

In the program design of heating and dehumidification, firstly, the microcontroller is initialized, and DHT11 collects the temperature in the cabinet. When the value exceeds the predetermined threshold, the PTC heating system is triggered. The temperature value after heating is monitored by DS18B20. When the temperature value is greater than the predetermined threshold, then Stop the heating of the PTC ceramic sheet. After the dehumidification is completed, the exhaust and shoe shine module will be triggered. The relevant data will be transmitted to the mobile terminal through Bluetooth. The mobile terminal user can also control the shoe cabinet through the serial port assistant.

3.2 Sterilization, deodorization and dust removal program design

In the program design of sterilization, deodorization and dust removal, the single-chip microcomputer is initialized, and the MQ135 detects the gas concentration in the cabinet. When the gas concentration is greater than the predetermined threshold, the ozone generator is triggered to generate ozone to oxidize the relevant components in the gas. After oxidation and shoe cleaning, there are bacteria and dust in the air, which are settled by the negative ion generator and then discharged through the ventilation duct.

4. System debugging of disinfection shoe cabinet

The system is tested, and the data collected by the temperature and humidity sensor is compared with the target value. When the humidity exceeds the predetermined threshold, the PTC ceramics will start heating and dehumidification, and the heating will stop when the temperature exceeds the threshold to prevent system damage caused by overheating. Detect the gas concentration. When the gas concentration in the cabinet is greater than the threshold, the ozone generator starts to work. At the same time, the negative ion generator performs sedimentation and dust removal.

After actual testing, all peripheral sensors can work normally (ON-work, OFF-stop). According to observations and related data, compared with ordinary electronic disinfection shoe cabinets, this system increases the efficiency of heating, dehumidification, sterilization and disinfection. In addition, the solar power supply plays the role of energy saving and environmental protection. During the debugging process, in view of the problem that the frequent reading of DS18B20 leads to inaccuracy, which causes the heating system to work all the time, a set of algorithm is added in the design, that is, a target value is set. If the temperature does not reach it, it will continue to rise. Once it reaches or When the threshold is exceeded, the heating system will be stopped immediately through the relay, and then the relay will be turned on again while the sterilization and deodorization system is being carried out, thus solving the problem of system abnormality caused by the occasional abnormal operation of DS18B20. According to the overall debugging and data display, each sensor is within the controllable range, realizing feedback control, and the entire system meets the expected requirements.

Summarize

The energy-saving shoe cabinet system designed based on closed-loop feedback control theory realizes the functions of temperature and humidity feedback, heating and dehumidification, sterilization and deodorization, and exhaust cleaning, effectively improving the intelligence, practicability, energy saving and environmental protection and low cost of home shoe cabinets At the same time, the system can carry out simple human-computer interaction through the wireless system, and has the characteristics of easy control. It has certain application value and innovative significance in the field of intelligent energy-saving shoe cabinets and even home furnishing.

The above is an example of the design and development of the closed-loop feedback control energy-saving shoe cabinet system based on the STM32 microcontroller introduced by Shenzhen Zuchuang Microelectronics Co., Ltd. If you have a need for the development of an intelligent disinfection shoe cabinet solution, you can rest assured to entrust it to us. We represent a variety of single-chip microcomputers, voice chips, dual-mode Bluetooth ICs, and wifi chips. Brands include Songhan MCU, Yingguang MCU, Jerry Bluetooth, Ankai Bluetooth, Allwinner, and Realtek. Our technical services include: PCB design, MCU development, Bluetooth solution, software and hardware custom development, APP development, small program development, WeChat official account development, etc. It can also undertake the design of intelligent electronic products, the development of living appliances, the research and development of beauty equipment, the application of Internet of things platform, the smart home control system, the development of TWS earphones, Bluetooth earphone speakers, the development of children's educational toys, the design of electronic education products, etc.