A ROS2 system for controlling a miniaturized Baader Allsky dome replica. The replica emulates the behaviour of the dome within an observatory. It includes a telescope, a camera and a weather station.
The ROS2 system is based on a service - client node structure.
The telescope mount is an Altazimuth mount. It rotates to the desired position given the altitude and azimuth in degrees.
The camera service can take images and analyze them using the Astromtetry API.
The weather service uses an external API as well, Open Weather. With the latitude - longitude coordinates it retrieves the weather in the area. This simulates a weather station in the observatory environment.
- Raspberry PI 3B +
- 5x Continuous rotation servos
- 1x 0-180 Servo (usage from 0-90)
- 1x LSM303
- 1x I2C-PCA9685
- 1x 3,3v & 5v PSU
- 8x Reed switches
- 8x 2.2k resistors
- 8x Mini neodymium magnets
Note that most of the components were reused, to do a proper prototype other components should be used.
The system was developed using the following:
- Python 3.6.9
- Ubuntu core 18.04 aarch64
- ROS 2 Dashing Diademata
- Install ROS 2 Dashing Diademata (Debian packages): https://index.ros.org/doc/ros2/Installation/Dashing/
- Install Colcon: https://index.ros.org/doc/ros2/Tutorials/Colcon-Tutorial/
- Remember to add the following to the ~/.bashrc file:
- source /opt/ros/dashing/setup.bash
- source {PATH}/ROS-observatory/ros_ws/install/setup.bash
echo "source /opt/ros/dashing/setup.bash" >> ~/.bashrc
echo "source /home/ubuntu/ROS-observatory/ros_ws/install/setup.bash" >> ~/.bashrc- Install pip3:
sudo apt-get install python3-pip- Enable the use of I2C of the raspberry pi:
sudo apt-get install -y python-smbus
sudo apt-get install -y i2c-tools
pip3 install adafruit-blinkaMore information here.
- Give user permissions to access
i2candgpiowithout being root.
The system uses the following libraries:
| adafruit_servokit | pip3 install adafruit-circuitpython-servokit |
| RPi.GPIO | pip3 install RPi.GPIO |
| adafruit_lsm303dlh_mag | pip3 install adafruit-circuitpython-lsm303dlh-mag |
| request | pip3 install request |
| json | pip3 install json |
First of all we need to launch the services. This can be done in two ways:
- Executing each service by its own:
ros2 run package_name service - Execute all services altogether:
ros2 launch launch.py
Once the services are up, all we need to do is send a request through a client node. This is done executing a command with the desired parameters:
ros2 run package_name client paramsThe dome service can perform the following actions:
| status | ros2 run dome_servcli client status |
| open | ros2 run dome_servcli client open |
| close | ros2 run dome_servcli client close |
The telescope service can perform the following actions:
| goto altitude azimuth | ros2 run telescope_servcli client goto 50 248 |
The camera service can perform the following actions:
| take_image | ros2 run camera_servcli client take_image |
| analyze_image file_name | ros2 run camera_servcli client analyze_image file_name |
With the command above, the camera analyzes the image through a web service (Astrometry.net) and returns the image with the tags.
| Raw Image | Analyzed Image |
|---|---|
 |
 |
The weather service can perform the following actions:
| info | ros2 run weather_servcli info |
It returns the weather information regarding the cooridnates (Latitude & Longitude) of your area using the openweathermap.org service.
@inproceedings{2016SPIE.9913E..2VV,
author = {{Vilardell}, Francesc and {Artigues}, Gabriel and {Sanz}, Josep and
{Garc{\'\i}a-Piquer}, {\'A}lvaro and {Colom{\'e}}, Josep and
{Ribas}, Ignasi},
title = "{Using Robotic Operating System (ROS) to control autonomous observatories}",
booktitle = {\procspie},
year = 2016,
series = {Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series},
volume = {9913},
month = jul,
eid = {99132V},
pages = {99132V},
doi = {10.1117/12.2232694},
adsurl = {https://ui.adsabs.harvard.edu/abs/2016SPIE.9913E..2VV},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}