The purpose of this project is to create a flexible and extensiable tool to design interactive touch based experiments for mice. For this, the open source NUI framework optimized for touch input called Kivy is used.
- Raspberry Pi 3 Model B
- Element14 7 inch touchscreen display
- Touchscreen enclosure
If you are not used to a GNU-Linux type environment or the Raspberry Pi, here are some good guides that can help.
Raspberry Pi:
Linux:
- https://www.funtoo.org/Linux_Fundamentals,_Part_1
- http://www.ee.surrey.ac.uk/Teaching/Unix/unixintro.html
The steps that follow describe how to prepare the Raspberry Pi for Kivy. For this, we will use Raspbian as our OS installed on a micro SD card. The full Raspbian version will used and can be downloaded from here: https://www.raspberrypi.org/downloads/raspbian/. To make the image on the micro SD card, it is recommended to use the tool called Etcher: https://www.balena.io/etcher/. Once Raspbian (Stretch used in for this project) is written, it can be inserted into the Pi's SD card slot. It will then boot and ask you to setup with a new root password and time as well as updates. Next, we will setup the OS so Kivy projects such as the one in this repository can run.
Kivy can be installed for the most part by following the guide in the docs: https://kivy.org/doc/stable/installation/installation-rpi.html. For this installation, it was found Kivy works best by installing globally. First, open terminal and run in order:
sudo apt-get updatesudo apt-get install libsdl2-dev libsdl2-image-dev libsdl2-mixer-dev libsdl2-ttf-dev \ pkg-config libgl1-mesa-dev libgles2-mesa-dev \ python-setuptools libgstreamer1.0-dev git-core \ gstreamer1.0-plugins-{bad,base,good,ugly} \ gstreamer1.0-{omx,alsa} python-dev libmtdev-dev \ xclip xsel
We then have to install the dependancies for Kivy and this project. Kivy utilizes Cython, a package that optimzes Python code by calling native C or C++ functions for ultimately more efficient memory and CPU usage. Along with Cython, install Pandas. This process will take a while, so feel free to do other tasks as the packages compile and install.
sudo pip install Cython Pandas
Next, the Rpi is ready to install Kivy globally.
sudo pip install git+https://github.com/kivy/kivy.git@master
Now, we have to change the config file for Kivy to tell it to accept touch input from the touchscreen. Open the config file with a text editor such as Vim using:
vim ~/.kivy/config.ini
Find the [input] section and add the following lines:
mouse = mouse
mtdev_%(name)s = probesysfs,provider=mtdev
hid_%(name)s = probesysfs,provider=hidinput
There is also an error with this version of Rasbian or Kivy not using openGL as the default renderer. To set it, add the line export KIVY_GL_BACKEND=gl in your .profile file and restart the Pi. Now, the system is ready to run the Kivy application.
Copy this repository by copying the URL and performing a git {url name} in a directory of your choice. Then go into it with cd {name of folder}. Run ls to verify all the files are there, and lastly, run the program with python main.py. To exit the program, you can either use the Esc key or ctrl-c.
The app shows a circle and square in two halves of the screen with a black background. It records how many times and at what time each button is pressed. The output of this recording is in a file called mouse_game_results.csv. Note, these buttons do not have any visual indication showing that they have been touched.
- Kivy: https://kivy.org/#home
- Etcher: https://www.balena.io/etcher/
- Kivy Docs: https://kivy.org/doc/stable/guide/basic.html