Path Tracer Tutorial

Log files produced from a simulation run can be used to generate a top-down view of the world along with visualization of each robot's path through the world over time.

1. Install the Ignition Fortress version of the SubT Simulator.
2. Put the path_tracer executable in your PATH

   export PATH=$PATH:~/subt_ws/install/lib/subt_ign
   

3. Make sure you have your simulation run logs files downloaded and unpacked.
4. Run the path generator script

   cd ~/subt_ws/src/subt/subt_ign/scripts
   ./generate_trajectory.bash LOG_FILE_PATH OUTPUT_PATH WORLD_NAME "CAMERA_POSITION"
   

   • LOG_FILE_PATH should be set to the directory containing the gazebo directory from your simulation run. The gazebo directory should contain the state.tlog and events.yml files.
   • OUTPUT_PATH should be set to the directory where the trajectory video will be saved.
   • WORLD_NAME is the name of the world, such as final_event_01.
   • CAMERA_POSITION is the "x y z" position to place the camera used to record the video. Make sure to include the quotes around the position. The following is a list of positions that work well for a few worlds:
     • final_prelim_01 "163 30 310"
     • final_prelim_02 "140 -100 400"
     • final_prelim_03 "90 0 260"
     • final_event_01 "195 0 317"
     • final_event_02 "91 32 300"
     • final_event_03 "247 0 421"
     • final_event_04 "161 140 382"
     • final_event_05 "30 30 100"
     • final_event_06 "79 95 367"
     • final_event_07 "100 -60 410"
     • final_event_08 "25 58 180"