MothPi

Installation

System packages

Required packages:

sudo apt-get update
sudo apt-get -y upgrade && sudo apt autoremove

sudo apt install -y python3-setuptools python3-dev python3-pip libsystemd-dev python3-gphoto2 python3-gpiozero wiringpi python3-systemd gphoto2 python3-yaml
sudo pip3 install -r requirements.txt

Correct time stamps

Preserve timing information as well as possible:

• Transport the camera with a battery, as it has an internal clock with limited power capacity; and check the correcttime in the camera when setting up; pictures then will have the correct timestamp.
• If the Raspberry Pi will be without internet connection, install fake-hwclock or optionally install a hardware clock.
• If it will have internet connection: Make sure that the systemd service systemd-timesyncd.service is enabled and started time zone is set correctly:

systemctl enable --now systemd-timesyncd.service
timedatectl set-ntp true 
timedatectl set-timezone "Europe/Berlin" # or any other timezone

Mothpi service

Also, the Mothpi program will run as user, so make sure that automatic start-up of user instances is activated:

loginctl enable-linger pi

Mothpi installation

The main Mothpi programm can be downloaded from this git repository.

git clone https://github.com/lumaku/mothpi ~/mothpi

If you use a development version and need an access token, set up an access token in Settings->Access Tokens, then use it to access this Mothpi repository.

MOTHPI_TOKEN=<token>
git clone https://gitlab-ci-token:${MOTHPI_TOKEN}@gitlab.lrz.de/visammod/mothpi ~/mothpi

The included script automates the updating process as well as other tasks.

Camera setup

• Switch the camera "ON".
• Make sure that PC connection over USB is activated. This can be verified by connecting it with USB cable to the Raspberry Pi. Then, the camera displays a "waiting for connection" message.
• To reduce power usage, switch off the display setting "Sucher" in the menu for "Display/Sucher" on Page 3 of the Gear ⚙️ page. (Sony Alpha 6000)
• Don't forget to activate the flash by pressing the flash button.

Run Mothpi

Start with mothpi.sh that provides a boilerplate for mothpi, including functions for:

• automatic updates,
• systemd services,
• reverse ssh tunnel to the main server and
• a pictures uploader.

Initialize with:

./mothpi.sh init

this will copy and enable systemd services and set up systemd service variables.

The core program that takes pictures is in mothpi/mothpy.py.

Mothpi App

The web app included in mothpi/app.py provides a web interface to check its status and change the configuration. It can be accessed on Port 8000. The IP address of the device is displayed on the e-Paper display, if available.

Example configuration page:

Mothpi default configuration

The mothpi configuration file will be saved in $HOME/.mothpi. Pictures are saved in /home/pi/pics/ and will be moved over to the server in regular intervals.

Periodic restarts are disabled by default, but can be activated over the configuration file.