Upload images and songs to a raspberry pi, giving them a title, a short description and a task. A receipt of the content will be printed out, identified by a QR code.

The QR can then be scanned, which will print out the content, along with the task, which you can complete with a friend in a care home.

• Raspberry Pi 3
• Thermal printer
• 8mp Pi camera
• USB speakers

• Vue application, served by the Pi:
• Volunteers can upload media they have saved on their phone.
• Volunteers can media they have uploaded.
• API which prints a QR code when new content is uploaded.
• Client to print content when scanned, using a camera and QR codes.

To use the Raspberry Pi so we can install and run printer-pals we need to power it and connect it to a mouse, monitor, and keyboard. Connect the mouse and keyboard over USB, and then connect to a monitor via the HDMI port. The last thing to do is connect it to power by plugging a 5v power supply into the micro USB port. The Pi should begin booting, opening up to desktop display.

Once the Pi has booted up we need to then open up a terminal window so we can start entering commands into the command line. To do this click on the 4th icon from the top left of the desktop display. This should open a a black window where you will see something like:

pi@raspberrypi: ~ $

You can start typing in your commands here.

We need to ensure printer-pals can access the camera and the printer over a serial connection. To do this we need to edit the Raspberry Pi's settings to enable the modules. Type the command below to bring up the settings menu:

sudo raspi-config

From the menu select option 5. Interfacing Options, then select P1 Camera, then Yes, then Ok. The camera is now enabled. To enable serial connections select 5. Interfacing Options, then P6 Serial, then No, then Yes, then Ok. The Pi should now be able to interface with the printer.

After this select finish, you should be prompted to reboot the Pi, but if this dialog box does not appear enter the command below to restart the Pi.

sudo shutdown -r now

To connect to the router we need to edit the file the Raspberry uses to store it's WiFi connections. To do this run the command

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

The file will have some text in it, you need to modify it to have the code below, replacing the SSID and Password placeholders with the credentials for the router you want to connect to. You can create a new network block for each individual network you wish to connect to.

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
  ssid="WIFI_NAME"
  psk="WIFI_PASSWORD"
  proto=RSN
  key_mgmt=WPA-PSK
  pairwise=CCMP
  auth_alg=OPEN
}

Save the file by pressing CTRL+X to exit, and then Y to save the file when prompted.

This won't take effect until the Pi is restarted. You can restart the Pi with the command:

sudo shutdown -r now

The Pi should restart and automatically connect to the router.

After connecting the Pi to WiFi, we can download printer-pals to the Pi so that we can begin installing the dependencies needed for it run properly. To download the project run the command:

git clone https://github.com/digitalinteraction/printer-pals.git
cd printer-pals

The first command will download the latest version of the project from Open Lab's Github account, and create a new folder called printer-pals with the project inside. The second command will then change our working directory to the project we just downloaded so we can continue setting up the project.

Now the Pi is connected to the internet we can install all of the dependencies and libraries printer-pals needs to run. This can be done with the command:

sudo ./install.sh

This will run a series of commands contained in the install.sh file, installing the NodeJS to execute the code, Mongo to store the data, and builds printer-pals so it is ready to run.

Check this has finished correctly. Once the script has finished you should see the following:

Checking mongo and versions
MongoDB shell version: 3.2.15

To set the Pi to run printer-pals at boot we need to tell it to run a script every time it turns on. Enter the command:

sudo cat run.sh > /etc/rc.local

This will override the usual scripts the Raspberry Pi runs at boot with a script we can use to manually start printer-pals.

We need to tell printer-pals what credentials and passwords it needs to connect to the database, and what it can use to seed session tokens when people log into the webapp. To do this enter:

nano .env

And add the following text, changing random_secret_string to some random text.

DEBUG=false
DB_USER=user
DB_PASS=password
DB_HOST=mongo
DB_NAME=database_name
PORT=27017
SALT_ROUNDS=10
APP_SECRET=random_secret_string

Now that everything is installed we can run printer pals using the command:

sudo ./run.sh

This will start the database, server, and the QR Code scanner.

Congration, you done it 🏆🎉

To update printer pals you need to run the command:

cd ~/printer-pals && git pull

This will fetch the latest version of the code from the server. You then need to restart the Pi, forcing it to run the latest version when it boots up. Do this by entering:

sudo shutdown -r now

Firstly, you need to setup a router, with the ssid printer-pals, and the password as print. Once this is setup plug in printer-pals and it should connect automatically.

Once connected to power printer-pals will begin serving a webpage which you can use to start uploading and printing media. Open a browser and navigate to:

http://printer

This will connect to the printer over the local network you just set up.

Create an account and start printing some fun tasks! 🖨