Have you ever SSH'ed into a robot to debug whether sensors are outputting what they should, e.g. rostopic echo /camera/image_raw?

If so, rosshow is for you.

This displays various sensor messages in a useful fashion using Unicode Braille art in the terminal so you don't need to fire up port forwards, rviz, or any other shenanigans just to see if something is working. It currently only supports types from std_msgs and sensor_msgs but support for more types is coming. Contributions welcome!

Prerequisites:

sudo pip install numpy pillow requests

This package works with both ROS1 and ROS2. You can add it to either a catkin (ROS1) or colcon (ROS2) workspace and it should work.

If you installed it to the system:

rosshow <topicname>

If you're using it from a catkin or colcon workspace:

rosrun rosshow rosshow <topicname>      # ROS1
ros2 run rosshow rosshow <topicname>    # ROS2

Most visualizations use Unicode Braille characters to render visualizations. If your terminal supports only ASCII, you can use the -a option for a purely ASCII-art render:

rosshow -a <topicname>

You can also force 1-bit, 4-bit, or 24-bit color modes if your terminal type is not detected correctly. You may need these when using rosshow inside of a screen.

rosshow -c1 <topicname>
rosshow -c4 <topicname>
rosshow -c24 <topicname>

You can rotate and tilt with the arrow keys, and zoom with the /- keys. This has been tested with Velodyne data. PointClouds from devices that don't have "x", "y", and "z" fields are not supported.

You can zoom with the /- keys.

The NavSatFix visualization fetches map tiles from OpenStreetMaps, so your machine or robot needs to have internet access to be able to view those. Otherwise, you'll still be able to see a trace of points.

The ASCII-only "-a" option works for all types. Here's what the NavSatFix message looks like on pure ASCII:

For most std_msgs numeric types you will get a time series plot.

Neat trick: You can reduce your terminal font size to get slightly higher resolution. Here's a nav_msgs/OccupancyGrid:

• nav_msgs/OccupancyGrid
• nav_msgs/Odometry
• nav_msgs/Path

• std_msgs/Bool
• std_msgs/Float32
• std_msgs/Float64
• std_msgs/Int8
• std_msgs/Int16
• std_msgs/Int32
• std_msgs/Int64
• std_msgs/UInt8
• std_msgs/UInt16
• std_msgs/UInt32
• std_msgs/UInt64

• sensor_msgs/CompressedImage
• sensor_msgs/FluidPressure
• sensor_msgs/Illuminance
• sensor_msgs/Image
• sensor_msgs/Imu
• sensor_msgs/LaserScan
• sensor_msgs/NavSatFix
• sensor_msgs/PointCloud2
• sensor_msgs/Range
• sensor_msgs/RelativeHumidity
• sensor_msgs/Temperature