With the rise of smart home systems, adding APP remote control functionality to disinfection cabinet control boards has become a mainstream upgrade trend. This function allows users to start/stop sterilization programs, adjust working modes, and check device status remotely via mobile phones. The implementation process mainly involves hardware upgrade, firmware development, APP development, and data communication docking, which is detailed as follows:

1. Hardware Upgrade of Disinfection Cabinet Control Boards

The original control board of traditional disinfection cabinets only supports button operation, so hardware expansion is the foundation for realizing APP remote control. The core is to add a wireless communication module and optimize the peripheral circuit to ensure stable data transmission.

1.1 Select a Suitable Wireless Communication Module

According to application scenarios and cost budgets, three mainstream modules are available for selection:

WiFi Module (e.g., ESP8266, ESP32): Suitable for household disinfection cabinets with stable home WiFi coverage. It features low cost, easy development, and direct connection to the home router to realize remote control via the public network. ESP32 is preferred for its dual-core processor and richer I/O interfaces, which can simultaneously handle communication and control tasks.

Bluetooth Module (e.g., Bluetooth 5.0 BLE): Suitable for short-range control scenarios (within 10 meters), such as small desktop disinfection cabinets. Users need to connect the mobile phone to the device's Bluetooth to operate. It has low power consumption and is suitable for battery-powered portable disinfection cabinets.

NB-IoT Module (e.g., BC28): Suitable for commercial disinfection cabinets in public places (e.g., restaurants, hospitals) without WiFi coverage. It uses the operator's cellular network for data transmission, supports remote control across regions, but has higher communication costs.

1.2 Optimize the Control Board Peripheral Circuit

Microcontroller (MCU) Compatibility Check: The original MCU of the control board (e.g., STM32, 51 series) needs to have enough UART/SPI/I2C interfaces to connect the wireless module. If the original MCU has insufficient resources, replace it with a model with stronger performance.

Power Supply Circuit Optimization: The wireless module requires stable 3.3V DC power supply. Add a low-dropout regulator (LDO) on the control board to convert the original 5V power supply to 3.3V, avoiding voltage fluctuations that affect communication stability.

Signal Isolation Protection: Add optocouplers between the wireless module and the MCU to isolate strong electrical interference from the disinfection cabinet's heating/UV lamp drive circuit, preventing the module from being burned out by voltage spikes.

1.3 Add Status Detection Sensors (Optional)

To enrich the APP's monitoring functions, additional sensors can be connected to the control board to collect device status data:

Temperature and Humidity Sensor (e.g., DHT11): Monitor the internal temperature and humidity of the disinfection cabinet, and display it on the APP in real time.

Door Switch Sensor: Detect whether the disinfection cabinet door is closed tightly. If not, send an alarm to the APP to avoid UV leakage.

Program Progress Sensor: Record the remaining time of the sterilization program and update it to the APP in real time.

2. Firmware Development of Control Boards

Firmware is the "bridge" between hardware and APP. It needs to realize three core functions: data collection, command execution, and wireless communication, which is usually developed based on C language or Arduino IDE.

2.1 Core Functional Logic of Firmware

Communication Protocol Customization: Define a set of simple and reliable data interaction protocols between the control board and the APP to ensure that commands and data are transmitted correctly. For example:

APP sends control command: 01 02 00 01 (representing "start UV sterilization mode, duration 30 minutes").

Control board returns status data: 02 01 25 00 (representing "device is running, current temperature 25℃, no fault").

The protocol needs to include header, command code, data segment, checksum, and tail to prevent data packet loss or error.

Command Parsing and Execution: The MCU receives the APP command via the wireless module, parses it according to the protocol, and controls the corresponding actuator (UV lamp, ozone generator, fan) to work. For example:

Receive "start command" → turn on the relay to drive the UV lamp and ozone generator.

Receive "mode adjustment command" → switch between high-temperature sterilization mode and UV-ozone combined mode.

Status Data Reporting: The MCU collects data from sensors (temperature, humidity, door status) and device operating status (program progress, fault code) at regular intervals, packages it according to the protocol, and sends it to the APP via the wireless module. The reporting interval can be set (e.g., 5 seconds/time) to balance real-time performance and power consumption.

2.2 Fault Handling Mechanism

Add fault judgment logic in the firmware to ensure the safe operation of the device:

If the door is opened during sterilization, the firmware immediately turns off the UV lamp and ozone generator, and sends an alarm message to the APP.

If the temperature exceeds the safe threshold (e.g., >85℃ for high-temperature disinfection cabinets), the firmware stops heating and reports an over-temperature fault to the APP.

3. APP Development and Function Design

The mobile APP is the user interaction terminal, which needs to be developed for iOS and Android systems respectively, or use cross-platform frameworks (e.g., Flutter, React Native) to reduce development costs. The core functions of the APP include device binding, remote control, status monitoring, and message push.

3.1 Device Binding Function

This is the first step for users to use the APP. The binding process varies according to the wireless module type:

WiFi Module Binding: The APP guides the user to enter the home WiFi name and password, and sends it to the control board via the broadcast function. The WiFi module connects to the router after receiving the information, and the cloud server records the device's unique ID and user account to complete binding.

Bluetooth Module Binding: The APP searches for nearby Bluetooth devices, displays the disinfection cabinet's device name, and the user completes binding by clicking to connect.

3.2 Core Control Functions

Remote Operation: Provide buttons such as "Start", "Stop", "Mode Switch" on the APP interface. Users can select sterilization modes (UV, ozone, high-temperature, combined mode) and set working time (15/30/60 minutes).

Status Monitoring: Display real-time data such as the device's current working mode, remaining time, internal temperature and humidity, and door status on the APP interface.

Timing Task: Allow users to set a timing start time on the APP. The firmware stores the task in the memory, and the device automatically starts the sterilization program when the time is up.

3.3 Message Push Function

Connect the APP to the cloud server to realize push notifications:

When the sterilization program is completed, the APP pushes a "task completed" message to the user.

When the device fails (e.g., over-temperature, door not closed), the APP pushes an alarm message in time to remind the user to handle it.

4. Cloud Server Docking (for Remote Control via Public Network)

If using WiFi or NB-IoT modules to realize remote control across regions, a cloud server is needed as a data transfer station between the control board and the APP.

4.1 Server Construction Options

Self-built Server: Suitable for manufacturers with technical strength. Use cloud servers (e.g., Alibaba Cloud, Tencent Cloud) to deploy TCP/IP or MQTT servers. MQTT protocol is preferred for its low power consumption and high efficiency, which is very suitable for IoT device communication.

Third-Party IoT Platform: Suitable for small and medium-sized manufacturers to reduce development costs. Use mature platforms such as Alibaba Cloud IoT, Tuya Smart, and connect the control board and APP to the platform according to the platform's API documentation.

4.2 Data Transfer Process

After the control board is connected to the network, it initiates a connection request to the cloud server and sends the device's unique ID for authentication.

The user logs in to the APP with an account, and the APP retrieves the bound device list from the server.

When the user operates the APP, the control command is sent to the cloud server first, and then the server forwards the command to the corresponding control board.

The control board executes the command and sends the device status back to the server, which then pushes the data to the APP for display.

5. Testing and Debugging

After completing hardware upgrade, firmware development, and APP development, comprehensive testing is required to ensure the stability of the remote control function:

Communication Stability Test: Test the data transmission success rate between the APP and the control board in different network environments (e.g., home WiFi, 4G/5G mobile network). The success rate should be ≥99%.

Function Compatibility Test: Verify whether all remote control functions (start/stop, mode adjustment, timing, fault alarm) work normally, and ensure that there is no delay or command loss.

Safety Test: Test the device's response when the network is disconnected. The control board should continue to execute the original program, and automatically reconnect to the server when the network is restored. At the same time, ensure that the APP's control commands have authority verification to prevent unauthorized operation.

6. Key Notes for Implementation

Cost Control: For household disinfection cabinets, the ESP8266 WiFi module is the most cost-effective choice, with a single module cost of less than $5.

Power Consumption Optimization: For battery-powered devices, use low-power modes of the wireless module (e.g., ESP32's deep sleep mode) to extend battery life.

Compliance with Standards: The developed APP needs to comply with the relevant regulations of the app store (e.g., Apple App Store's review guidelines, Android's Google Play policies) to ensure successful release.