Fink watch

This repository contains the script to display the number of alerts per night processed by the astronomical broker Fink in real-time. The watch uses a Raspberry Pi to control the LCD Display Module, and it polls alert information from the Fink Kafka cluster.

Display

Hardware requirements

The Fink watch is made of a Raspberry Pi board, and the 1.28inch LCD Display Module from Waveshare. It requires internet access to poll alert information.

While it should work on any version of the Raspberry Pi, we have only extensively tested it on a Raspberry Pi 4 running a 64-bit operating system. We plan to test it on a Raspberry Pi Zero with a 32-bit operating system at some point.

The code currently only works for a 240x240 screen. If you want to use a different resolution, you will need to adapt the code provided in lib/LCD_1inch28.py. Please note that this part of the library is based on examples provided by Waveshare:

wget https://files.waveshare.com/upload/8/8d/LCD_Module_RPI_code.zip

Installation

First, clone this repository:

git clone https://github.com/JulienPeloton/fink-watch.git

Demo mode

For local debugging, you only need to install the Python dependencies (tested for Python > 3.9):

python -m venv watchenv
source watchenv/bin/activate

pip install .

Raspberry Pi

You need to enable the SPI interface on the Raspberry first:

sudo raspi-config
# Choose Interfacing Options -> SPI -> Yes  to enable SPI interface

Then reboot the Raspberry to activate the change. Then install the latest version of WiringPi from the release:

# Adapt with the latest version, and your platform
wget https://github.com/WiringPi/WiringPi/releases/download/3.12/wiringpi_3.12_arm64.deb

sudo dpkg -i wiringpi_3.12_arm64.deb

Check that you have access to gpio:

gpio -v
# should print version, and details about the board

Finally install Python dependencies:

python -m venv watchenv
source watchenv/bin/activate

pip install .

Usage

We provide a Python script app.py with options to ease the configuration of the watch:

usage: app.py [-h] [--demo] [-width WIDTH] [-height HEIGHT] [-display DISPLAY]
              [-observatory OBSERVATORY] [-alert_per_deg ALERT_PER_DEG] [-topic TOPIC]

Launch the Fink watch

options:
  -h, --help            show this help message and exit
  --demo                If specified, display a fix image on the local computer instead of
                        the LCD screen
  -width WIDTH          Width size in pixels. Default is 240
  -height HEIGHT        Height size in pixels. Default is 240
  -display DISPLAY      What to display on screen: watch, logo. Default is watch.
  -observatory OBSERVATORY
                        Name of the observatory to set the local time for the `clock`
                        option. Default is ZTF.
  -alert_per_deg ALERT_PER_DEG
                        Number of alerts per degree (for the alertmeter). Default is 1000
  -topic TOPIC          Topic name to read alerts. Default is fink_ztf_<YYYYMMDD>.

Static demo

You can simply call the script using:

python app.py --demo

And you should see a similar display than the screenshots above. This is quite useful for testing and debugging.

Deployment on the screen using the Raspberry

Simply execute the script, and set arguments if need be:

# default display is for ZTF
python app.py


# Switch to Rubin
python app.py -observatory rubin -alert_per_deg 10000 -topic <the_topic_name_for_rubin>

Troubleshooting

Kafka: _TIMED_OUT_QUEUE

If you get the error signal cimpl.KafkaException: KafkaError{code=_TIMED_OUT_QUEUE}, this means you've been disconnected from the Kafka cluster by the server. Just relaunch the watch.

Acknowledgments

• Waveshare for providing part of the library to interact with the LCD module.
• HadrienG2 for providing the cool project name!