week16

ASSIGNMENTS

Week 16 - Interface and Application Programming

This week's assignment was:

- Write an application that interfaces with an input and/or output device that you made, comparing as many tool options as possible.

First I decided to make a program/app that I will use in my final project. It will be linked to the device that I made “output” from a previous week. The program is a temperature sensor that will measure the water temperate after the distillation in the extractor. The program that I used is App Inventor. I did not know anything about App Inventor, so a Guru taught me the basic tools.

I tried to make an android interface to interact with the Arduino. I have chosen the mobile platform due to its wide spread use. I intend to use a Bluetooth module for this assignment to speak to the board and the phone. Since I have an IPhone, I used the Guru’s phone, which is Android to run the App.

Bluetooth module HC-05

HC-05 module is an easy to use Bluetooth SPP (Serial Port Protocol) module, designed for transparent wireless serial connection setup. There is lot of information regarding the pinouts and usage on the internet. A few useful links are itead.cc/HC-05 and developer.mbed.

Below is a schematic of the Project:
At first I couldn’t think of a way to make the thermometer work with my project. So, I sat down with one of our gurus and he drew a schematic sketch to help me understand how the thermometer would work with an app and my project. When we worked together he reminded me how to do the math since I had a brief electrical course at my university. Bellow you can see the math that was done. Basically, I had to figure out how many resistors I would need for my Bluetooth device. After doing the math I concluded that I needed three parallel resistors of 10K.

Below is a picture of how Adriano connects to the Bluetooth connector using the color-coded jumper cables.

MIT Appinventor:

I read and followed this tutorial: http://archive.fabacademy.org/archives/2017/fablabtrivandrum/students/312/exercise16.html

The App Inventor is a free, cloud-based service that can be accessed using a web browser. The apps made using the app inventor could be tested on the android phone using the companion app. There are a good amount of learning content available like the ones as beginner-videos, app inventor tutorials, unofficial introduction. Also, to use the Bluetooth on app inventor, there are numerous resources available like the one on, App inventor Bluetooth.

I created an app by going through the various tutorials and with the help of the Guru, the Design and the blocks screen are shown in the images below.

After programming, my app looked like this:
A picture of a thermometer without the temperature (Celsius degree).

Then I clicked on “Search for a Bluetooth devices”.
After that, a window will open like the image below. Then I needed to select the Bluetooth transmitter in this case was the HC-06.

Once the steeps is completed, the app will show you the temperature.

The Initial testing using Arduino:

I programmed the board by using Arduino.
First I needed to download the Dallas Temperature at the Arduino library by clicking: Sketch > Include library> DallasTemperature.
Then the Guru helped me to program the board since I don’t have a lot of experience.
We worked together for a while figuring out the correct code for my specific project.
Below you can see the screen shots of my coding:

Here it is a video of it working: https://youtu.be/r_3M3zgIKjc

Video:

If you have any troubled understaniding how to do these steps here is another tutorial:

http://archive.fabacademy.org/archives/2017/fablabtrivandrum/students/312/exercise16.html

Project Files:

• Arduino code