Android Application For Multi-Sensor Data Monitoring

The Android Application For Multi-Sensor Data Monitoring system centers around an Arduino Uno development board that continuously reads analog voltage signals from two LM35 temperature sensors. Each LM35 sensor outputs a linear analog voltage directly proportional to its temperature in degrees centigrade, which the Arduino Uno captures using its built-in analog-to-digital converter channels. The microcontroller processes these raw analog readings into readable temperature values. To transmit this data wirelessly, an HC-05 Bluetooth module is interfaced with the Arduino's serial communication pins, sending the sensor metrics over a short-range wireless radio frequency link to an Android smartphone. On the mobile device end, a custom application built via MIT App Inventor (named temp_multi_sensor.apk) pairs with the HC-05 module, receives the incoming data stream, and presents the real-time temperatures from both sensors clearly on the screen. The entire physical circuit is prototyped using a breadboard or custom PCB and interconnected with standard connecting wires to route power, ground, and signal paths between the Arduino, sensors, and Bluetooth transceiver.