Sending Data from Arduino to Android using Bluetooth

Question

I am trying to do a project based on arduino and Android in which I want to use ultrasonic sensors and Bluetooth module hc-05 . I want to detect any obstacle using ultrasonic and send it's distance to Android app using Bluetooth. I am completely new to arduino and have never used it before . How could I connect both the Bluetooth and ultrasonic sensor to arduino uno board without using breadboard? Is it possible to connect both of them without using breadboard and just the jumper wires?

Answer 1

HC-05 runs at 3.3V, make sure you do level conversion from 5V to 3.3V using a zener diode. Or buy a level converter if you are new to electronics. If you don't, there is a good chance you will blow up the HC-05. If you could add a photo we can see if its already done on the Bluetooth module, then you need not worry about level conversion

HC-05 is basically a wireless serial port over bluetooh. On arduino create a software serial post using the library SoftwareSerial and send the sensor data to that serial port

There are libraries available for popular HC-SR04 ultrasonic sensor, if that is the sensor you are using.

For testing on android many app are availables like Bluetooh Terminal, you can receive the data sent from arduino.

Yes the whole project can be done without breadboard using connecting wires.

Answer 2

You can connect the Bluetooth Module and Ultrasonic Sensor with jumper wires directly to the Arduino.

Depending upon the Ultrasonic Sensor you are interfacing, there must be a library or a sample code. You can tweak the code to get the distance in your desired format or variable.

As far as the Bluetooth is concerned, you can operate it at 3.3v or 5v depending upon the module you use. Most of the Bluetooth module support both 3.3v and 5v - as they have voltage regulators on their break out. I have used these and they work on 3.3v as well as 5v

For instance, check the Bluetooth HC - 05 Module in the below link :

http://www.amazon.in/Verve-VTA009-Bluetooth-Module-HC-05/dp/B00S15XTG8?tag=googinhydr18418-21&tag=googinkenshoo-21&ascsubtag=7a58e842-4c10-40bf-a48f-339edef372a7

For implementing the Bluetooth communication, prefer using the Software Serial. If you connect the Bluetooth HC 05's Rx and Tx to the Arduino's Hardware UART Pins, there can be unpredictable results. I have experienced that using HC05 with Software Serial is reliable. Additionally, you can use the Serial Monitor to debug your code at the same time. I mean, you can send the same data on Software Serial and the Serial port and check if things are as desired.

You can implement, the HC-05 Software Serial at 9600 baudrate. 9600 is the default baudrate on most HC 05 Modules.

For developing the Arduino code and testing it, you can use a terminal client like PuTTY on you computer. You need to establish a bluetooth connection between your computer and HC 05.