How to Receive Arduino Sensor-Data on Your Android-Smartphone

In default the Arduino is not equipped with a display to visualize measuring-data, for example from your temperature or your pressure Sensor. If you want to get the data shown you need a PC, printing the data to the console or mounting a display directly to the Arduino. So there is no simple way to WIRELESSLY visualize measuring-data.

In this instructable i will show you, how to transfer measured Sensor-datain realtime from your Arduino-Mikrocontroller to your Android-Smartphone via Bluetooth.

Step 1: Preparing HC-05/HC-06 and Arduino

Requirements:

-Arduino

-Bluetooth-Module (HC-05, HC-06, ...)

-Android-Device

-App "Arduino Bluetooth Data"

The Bluetooth-Module HC-05/HC-06 is communicating with the Arduino via the UART-Interface. Every message the Arduino wants to send, is first given to the Bluetooth-Module, which sends the message wirelessly. To avoid problems with the UART, Arduino and Bluetooth-Module have to use the same baud-rate (in default 9600). It is possible to change the baud-rate and the password (and many other things) of the HC-05/HC-06, but this is not part of this instructable.

At first we have to do the wiring. The HC-05 has to be connected as descripted.

Wiring HC-05:

-GND of HC-05 to GND Arduino

-VCC of HC-05 to 3.3V Arduino

-TX HC-05 to Arduino Pin 10 (RX)

-RX HC-05 to Arduino Pin 11 (TX)

Important: HC-05 RX ist not connected to Arduino RX and vice versa.

Connect the Arduino to your PC and upload the following Code:

/*Developer: Frederik Hauke

Important Notices:

This Arduino-Code is written for Visualizating measurement data from a microcontroller via Bluetooth.

Before starting this application, the Bluetooth-Modul (HC-05) has to be coupled to the Smartphone.In the special case of the HC-05 the default PinCode for initiating the Coupling-Process is "1234".

Wiring: GND of HC-05 to GND Arduino, VCC of HC-05 to VCC Arduino, TX HC-05 to Arduino Pin 10 (RX) RX HC-05 to Arduino Pin 11 (TX) */

#include <SoftwareSerial.h>

SoftwareSerial BTserial(10, 11); // RX | TX

int sensorPin = A0;

int sensorValue = 0;

void setup() {

BTserial.begin(9600); }

void loop() {

sensorValue = analogRead(sensorPin);

//IMPORTANT: The complete String has to be of the Form: 1234,1234,1234,1234;

//(every Value has to be seperated through a comma (',') and the message has to

//end with a semikolon (';'))

BTserial.print("1234");

BTserial.print(",");

BTserial.print("1234.0");

BTserial.print(",");

BTserial.print("1234 hPa");

BTserial.print(",");

BTserial.print("500 ml/s");

BTserial.print(",");

BTserial.print(sensorValue);

BTserial.print(";");

//message to the receiving device

delay(20);

}

Step 2: Android App "Arduino Bluetooth Data"

The following app intents to process the incoming measuring-data and visualisates them:

https://play.google.com/store/apps/details?id=com....

Before using the app the Bluetooth-Module (HC-05/HC-06) has to be coupled to the Android in the system-preferences. In the special case of the HC-05 the default PinCode for initiating the Coupling-Process is "1234" or "0000".

If both devices are coupled, go to the app, pick the HC-05/HC-06 and click the red connect-button. "Arduino Bluetooth Data" should establish a serial connection.

In the Arduino-Code you determine on your own which values you want to send to the Android-Device. Just change these lines and fit in your own values:

BTserial.print(yourownValue);

Besides you can set a higher sampling-rate by lowering the delay: delay(yourownValue);

Feel free to do some experiments! Please, let me know, if something is not explained precisely enough!