spaceros_gz_demos

This is a ROS 2 package demonstrating how to use Gazebo Harmonic for robotic simulations in the Space ROS environment. This package is meant to serve as a baseline for how to create Gazebo worlds, set them up with the appropriate plugins for sending controls and receiving data, and bridge these topics to ROS. The simulated worlds use realistic gravity and include a submersible robot on Enceladus, the Perseverance rover and Ingenuity helicopter on Mars, a space capsule docking to the ISS, and two rovers on the Moon.

This package was made by David Dorf and Katie Hughes for the NASA Space ROS Sim Summer Sprint Challenge. The relevant PR in the Space ROS demos repository is here.

space.mp4

Docker setup

One time setup: If you don't have Docker, install it with sudo apt install docker.io. You will have to add yourself to the Docker user group with sudo usermod -aG docker $USER, then run newgrp docker to avoid permission errors with Docker daemon. You will need to reboot for these changes to take effect on your system. You will also to run xhost +local:docker on your first time to allow Docker to connect to gui-based application such as Gazebo and RViz.

1. Navigate to the docker directory.

2. Build the Docker image locally with

   ./docker_build.sh

3. Start the Docker container with

   ./docker_start.sh

4. Once you have a running container, to get another shell, run

   ./docker_shell.sh

Running code in the Docker container

1. Once you are in the Docker container, run colcon build (you should be in the ~/spaceros/ws directory)

2. Run source install/setup.bash

3. Start one of the demos with ros2 launch spaceros_gz_demos moon.launch.xml, mars.launch.xml, enceladus.launch.xml, or orbit.launch.xml.

Moon

Launch the moon demo with the following command:

ros2 launch spaceros_gz_demos moon.launch.xml

This world contains an X1 rover holding a truss that can be detached, an X2 rover, and a solar panel with one controllable joint on a lunar environment. Images, camera info, laser scans, point clouds, and odometry topics are provided for each robot. Additionally, each rover can be commanded as a differential drive system via a commanded base twist. This world uses the Selenographic Coordinate System (SCS).

Click here for information about the topics available in this demo.

Topic Name	Topic Type	Description
/X1/camera_front/camera_info	sensor_msgs/msg/CameraInfo	Camera info for X1's front camera
/X1/camera_front/image	sensor_msgs/msg/Image	Image on X1's front camera
/X1/cmd_vel	geometry_msgs/msg/Twist	Used to command the X1's base velocity
/X1/front_laser/scan	sensor_msgs/msg/LaserScan	Laser scan from the X1's camera
/X1/front_laser/scan/points	sensor_msgs/msg/PointCloud2	Point cloud from the X1's camera
/X1/imu_sensor/imu	sensor_msgs/msg/Imu	IMU data from X1
/X1/odometry	nav_msgs/msg/Odometry	Base odometry topic from X1
/X1/odometry_with_covariance	nav_msgs/msg/Odometry	Odometry with covariance from X1
/X1/truss/attach	std_msgs/msg/Empty	Used to attach the truss on the back of the X1
/X1/truss/detach	std_msgs/msg/Empty	Used to detach the truss on the back of the X1
/X2/camera_front/camera_info	sensor_msgs/msg/CameraInfo	Camera info for X2's front camera
/X2/camera_front/image	sensor_msgs/msg/Image	Image on X2's front camera
/X2/cmd_vel	geometry_msgs/msg/Twist	Used to command the X2's base velocity
/X2/front_laser/scan	sensor_msgs/msg/LaserScan	Laser scan from the X2's camera
/X2/front_laser/scan/points	sensor_msgs/msg/PointCloud2	Point cloud from the X2's camera
/X2/imu_sensor/imu	sensor_msgs/msg/Imu	IMU data from X2
/X2/odometry	nav_msgs/msg/Odometry	Base odometry topic from X2
/X2/odometry_with_covariance	nav_msgs/msg/Odometry	Odometry with covariance from the X2
/solar_panel/joint	std_msgs/msg/Float64	Used to command the joint of the solar panel
/tf	tf2_msgs/msg/TFMessage	TF topic containing odometry from both the X1 and X2

Mars

Launch the mars demo with the following command:

ros2 launch spaceros_gz_demos moon.launch.xml

This world contains models of the Perseverance rover and the Ingenuity helicopter on a Martian surface. The Ingenuity helicopter contains a rechargable battery that simulates it charging from its solar panel. Ingenuity can be commanded to fly. Perseverance can be commanded as a differential drive system, and its arm joints can also be commanded to move. Odometry, image, depth, and point cloud topics are also published for both robots. Perseverance and Ingenuity models are meant to be as close to their real-life counterparts as possible.

Click here for information about the topics available in this demo.

Topic Name	Topic Type	Description
/ingenuity/battery_recharge_start	std_msgs/msg/Bool	Publish True to start recharging the battery, and False to stop
/ingenuity/battery_state	sensor_msgs/msg/BatteryState	Used to view the current battery charge
/ingenuity/bottom_blades/thrust	std_msgs/msg/Float64	Command thrust to the bottom set of blades
/ingenuity/top_blades/thrust	std_msgs/msg/Float64	Command thrust to the top set of blades
/ingenuity/camera	sensor_msgs/msg/Image	Image from Ingenuity's camera
/ingenuity/camera_info	sensor_msgs/msg/CameraInfo	Camera info from Ingenuity's camera
/ingenuity/depth_camera	sensor_msgs/msg/Image	Depth image from Ingenuity's camera
/ingenuity/depth_camera/points	sensor_msgs/msg/PointCloud2	Point cloud from Ingenuity's camera
/ingenuity/odometry	nav_msgs/msg/Odometry	Odometry from Ingenuity
/ingenuity/swashplate_1/joint	std_msgs/msg/Float64	Used to tilt Ingenuity's propellers around the x axis (range: -0.3 - 0.3)
/ingenuity/swashplate_2/joint	std_msgs/msg/Float64	Used to tilt Ingenuity's propellers around the y axis (range: -0.3 - 0.3)
/perseverance/arm/joint_1	std_msgs/msg/Float64	Command joint 1 on Perseverance's arm (range: -3.14 - 3.14)
/perseverance/arm/joint_2	std_msgs/msg/Float64	Command joint 2 on Perseverance's arm (range: -3.14 - 3.14)
/perseverance/arm/joint_3	std_msgs/msg/Float64	Command joint 3 on Perseverance's arm (range: -3.14 - 3.14)
/perseverance/arm/joint_4	std_msgs/msg/Float64	Command joint 4 on Perseverance's arm (range: -3.14 - 3.14)
/perseverance/arm/joint_5	std_msgs/msg/Float64	Command joint 5 on Perseverance's arm (range: -3.14 - 3.14)
/perseverance/camera	sensor_msgs/msg/Image	Image from Perseverance's camera
/perseverance/camera_info	sensor_msgs/msg/CameraInfo	Camera info from Perseverance's camera
/perseverance/camera_yaw	std_msgs/msg/Float64	Used to tilt Perseverance's camera around the yaw/azimuth (range: 0 to 6.28)
/perseverance/cmd_vel	geometry_msgs/msg/Twist	Used to command Perseverance's base velocity
/perseverance/depth_camera	sensor_msgs/msg/Image	Depth image from Perseverance's camera
/perseverance/depth_camera/points	sensor_msgs/msg/PointCloud2	Point cloud from Perseverance's camera
/perseverance/odometry	nav_msgs/msg/Odometry	Odometry from Perseverance
/tf	tf2_msgs/msg/TFMessage	Topic containing odometry transforms for both robots

Enceladus

Launch the Enceladus demo with the following command:

ros2 launch spaceros_gz_demos moon.launch.xml

This world contains a submarine model in a liquid ocean meant to simulate the surface of Encaledus. The submarine has sonar and odometry topics, and has a buoyancy engine that allows it to rise or sink, in addition to commandable thrusters on its left and right sides.

Click here for information about the topics available in this demo.

Topic Name	Topic Type	Description
/submarine/buoyancy_engine	std_msgs/msg/Float64	Used to determine the volume of air in the buoyancy engine, which will either lower or raise the submarine (range: -30.0 - 30.0)
/submarine/left_thrust	std_msgs/msg/Float64	Control the left thruster
/submarine/right_thrust	std_msgs/msg/Float64	Control the right thruster
/submarine/odometry	nav_msgs/msg/Odometry	Odometry of the submarine
/submarine/sonar	sensor_msgs/msg/LaserScan	Laser scan correspoinding to sonar points
/submarine/sonar/points	sensor_msgs/msg/PointCloud2	Submarine's point cloud

Orbit

Launch the orbiter demo with the following command:

ros2 launch spaceros_gz_demos orbit.launch.xml

This world contains a model of the International Space Station in orbit above the Earth alongside a commandable capsule that it can try to dock at. Laser scan and point cloud data is also provided.

Click here for information about the topics available in this demo.

Topic Name	Topic Type	Description
/capsule/lidar	sensor_msgs/msg/LaserScan	Laser scan from capsule
/capsule/lidar/points	sensor_msgs/msg/PointCloud2	Point cloud from capsule
/capsule/thrust/pitch	std_msgs/msg/Float64	Control the pitch of the capsule
/capsule/thrust/push	std_msgs/msg/Float64	Control the push of the capsule
/capsule/thrust/yaw	std_msgs/msg/Float64	Control the yaw of the capsule

Additional Information

Installing Outside of Docker

If you would like to install this package outside of Docker, you can follow the instructions below. Note that you will need to have ROS 2 installed on your system.

1. Install Gazebo Harmonic and ROS 2 Gazebo packages by following the instructions here.
   • Pay special attention to the compatibility of the ROS 2 version with Gazebo Harmonic and additional packages for ROS 2 that you'll need to install.
2. Clone this repository into your ROS 2 workspace in the src directory.
3. Run colcon build in the root of your workspace.
4. Source the setup file with source install/setup.bash.
5. Start one of the demos with ros2 launch spaceros_gz_demos moon.launch.xml, mars.launch.xml, enceladus.launch.xml, or orbit.launch.xml.

Getting Visualizations in Gazebo

If you would like to visualize camera image feeds or laser scans in Gazebo, you can add an Image Display or Visualize Lidar plugin to the Gazebo GUI from the top right menu. You can then select the topic you would like to visualize from the plugin's menu.