2nd project: Android controlled LED lighting

Overview

This project is about the use of an android phone to control LEDs via bluetooth. The system basically consist of an android phone, Arduino UNO, and bluetooth module. The android phone, through an application, sends data to Arduino via bluetooth. The Arduino UNO prototyping module then process the data from the android phone and control the brightness of each LED. The brightness control of each LED is implemented by using PWM pins of the Arduino UNO. The hardware can be powered by a 9V battery or a DC supply between 9 to 12V.

The Android Application

The application is made using sliders to vary the brightness of the LEDs. Each slider has a value of 0 to 255 from which  internet colors can be easily reproduced using the 3 sliders. Establishing the communication link is also done in the application. Basically, the app can search for other bluetooth devices, query for paired devices, establish RFCOMM channels/sockets, connect to a device, and send data over bluetooth.

Arduino UNO

Arduino UNO is an open-source electronics prototyping platform based on a flexible, easy-to-use hardware and software. It serves as the processor of the data from android phone. The value 0 to 255 from the android phone is translated to PWM wave with a frequency of approximately 490Hz to the pins 9, 10, and 11.

Bluetooth Module

The datasheet states that signal can reach up to 100m but actual distance may depend on the other communicating device. This module is using the UART interface in SPP configuration to connect to the Arduino UNO. In essence, the bluetooth module acts as a cable replacement between two devices.

Below is a demo video of the project.

RB Pace calculator

My very first Android app


Are you a runner? Do you use Android phone?
Then this application might be useful for you

Finally, here is my first Android app. It is a simple application I made for runners to calculate for their average pace for a race. Being a runner myself, I thought that this application could be useful to become handy in a runner's phone. It was actually based from an application that I made for my running group's website.


You may download it here.
Android v2.2 and above.


Please feel free to comment, suggest and report bugs in the comments section.

Hello Android World!

Since I was not able to spend my holidays in my home country, I was left here with nothing to do. So to make my Christmas vacation somehow productive, I started studying Android Development and writing this blog to document it and share.

What is Android?

Well, according to Wiki, Android is a mobile operating system initially developed by Android Inc. Android was bought by Google in 2005. Android is based upon a modified version of the Linux kernel. Google and other members of the Open Handset Alliance collaborated to develop and release Android to the world. (Read here for more details)

Android Development

Here are the basic things we need to start developing Android apps:

1. Check your PC if it meets the minimum System Requirement.

2. Android Software Development Kit (Android SDK) download here

3. ADT Plugin for Eclipse (if you'll be developing in Eclipse)

   - Before you can install or use ADT, you must have a compatible version of Eclipse installed on your development computer. download here

     - You may also use IDE of your choice.

4. Download Platforms and other components.

5. Start Exploring the Android SDK.

Practically everything we need to get started (from setup to sample codes) can be found in this well-documented site.