2 Overall Scheme Design of the System
The system uses a three-tier Internet of things architecture, from top to bottom is the
management layer, transmission layer, and acquisition layer. The overall structure of
the system is shown in Fig. 1.
Data acquisition layer mainly collects data, using ESP8266 module embedded
Wi-Fi and MCU as the main control chip, carrying smoke sensor to collect monitoring
data.
As an intermediate bridge, the transmission layer mainly completes the two-way
communication between the acquisition layer and the management layer. This system
uses Wi-Fi to communicate, avoiding the wiring problem of wired transmission,
making data transmission more convenient and stable.
The management layer is composed of server and app. When the server receives the
monitoring data transmitted by the data acquisition terminal, it will update and save it
in the database. App requests monitoring data from the server constantly, which is used
to update the data displayed in the app interface in real time.
3 Hardware Design
Hardware design is the basis of system function realization, which mainly includes:
main control chip, power supply circuit, smoke monitoring circuit, relay control circuit,
etc. The structure is shown in Fig. 2.
Management Layer
Transport Layer
Acquisition Layer
Smoke Sensor
Fan
Node Control Terminal
WIFI Comunication
Server
Android APP
Fan
Smoke Sensor
Fig. 1. System structure diagram
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