An Open-Source platform to create digital devices and interactive objects that sense and control physical devices.
Today i will present the first steps of my project named "Detecting forestry fire focus, using Lora protocol". The main objective of this project is create a tool for help firemen and foresters detect and contain fires, before they spread over the forest. In Brazil, this type of event occur practically all year, but is aggravated when the air becomes drier. The number of incidents per year is about 68000, being largely caused by incorrect disposal of cigarettes on the highway .
An example of forestry fire caused by cigarette discarded improperly.
How it Works ?
To develop this system, we need to consider that detecting fire outbreaks within a forest is not an easy task due to access barriers and totally unstable environment. Knowing these problems, my approach is based in the use of simple sensor nodes, built using cheap microcontroller and cheap wireless communication modules to cover the forest area and send alerts to authorities using the follow process:
- When a fire focus happen in a tree, or in plants small changes will happen in the environment, such as increased room temperature, or signs of airborne smoke.
Example of fire focus in a tree.
2. When a expressive change on environment variables be detected by cheap microcontroller sensors, will be start to echoes the data to lora gateway.
Cheap microcontroller will be emit the data about the environment.
3. When you emit the distress signal to the gateway, two probably things can happen, the data can be receive successfully by gateway, or the wireless signal can't be reach to gateway due to obstacles or interference. A way to avoid these obstacles, consists of structuring the sensors to work in a mesh format allowing the data to be forwarded to any node of the mesh (including the gateway).
4. When the data finally reaches the gateway of network, it will be forwarded to a secondary node, which will be responsible for inform the user about the forest fire. The gateway, is composed by an Arduino MKR WAN 1300 Lora Powered and the same cheap radio used in forest nodes.
when the signal arrives at the gateway, it is sent to its final destination.
The Forest Node
To detect the environment changes, we created two types of Forest nodes, the first type of node has based in the presence of smoke on environment. In this node, the microcontroller is able to detect changes in air quality and send an alert message to the gateway when the smoke level reaches a critical value for the environment. The smoke detector node is basically composed of an Arduino Nano, which will be responsible for monitoring the environment during specific time intervals. In addition, it also consists of a NRF24l01, a low-cost radio capable of operating at 2.4 Ghz frequency. And finally, we use an MQ-2 sensor to detect the amount of smoke condensed in the air.
Smoke node components.
The second type of node elaborated for this project, consists of the temperature node, this sensor node is able to detect variations in temperature and inform the gateway when a sudden change of temperature occurs in the environment. This node is composed of an Arduino Pro mini, which will be responsible for detecting the variation of temperature in the environment, a nrf24l01 +, for communication with gateway and neighbor nodes, and a BME280 sensor, a temperature sensor of high precision and low energy consumption .
To route the sensor network data to final user, we need a microcontroller able of transmit this data for a long distance. In this case, the LoRa protocol will be ideal due to its long reach and low power consumption. With this, we will use the Arduino MKR WAN 1300 which has a long range chip. However we will need to establish communication with the network nodes to obtain the data. With this we will build one hat (Hardware at top) to facilitate the connection between Arduino and NRF24l01.
Gateway Components. Gateway Assembly.
To provide informations about the forest under monitoring, we build a dashboard using Electron framework where the user can get informations about temperature, alerts about a region, humidity, pressure and the air quality based in data provided by forest sensors. To receive the data from sensor network, you will need to use two Arduino MKR WAN 1300, when one will be connected using serial in computer running these dashboard, and the other node will works like gateway, providing a bridge between user and low cost network.