RACER ROS 2 Pillar Demo

This repository contains a ROS 2 Humble port of the RACER multi-drone exploration demo. The main runnable scenario is the pillar-map demo with four simulated drones, local point-cloud sensing, RACER exploration/planning, and RViz2 visualization.

This port is based on the original Robotics-STAR-Lab/RACER codebase, which implements rapid collaborative exploration with a decentralized multi-UAV system.

10-Run Demo Benchmark

Latest headless pillar-demo benchmark, generated on 2026-05-26 with:

ROS_LOG_DIR=/tmp/racer_ros_logs tools/benchmark_pillar.sh --runs 10 \
  --timeout-sec 180 --output benchmark_results/pillar_runs_10.csv \
  --log-dir benchmark_results/logs_10

Runs completed	Completion modes	Avg exploration time	Avg total path length	Avg wall time	Avg coverage
10/10	9 no_grid, 1 stable_metrics	45.520 s	147.016 m	50.782 s	94.345%

Metric	Mean	Median	Min	Max	Stddev
Exploration time (s)	45.520	43.112	38.735	62.537	6.875
Total path length (m)	147.016	145.374	128.024	169.468	11.281
Coverage (%)	94.345	94.401	93.564	95.001	0.511

All commands below are meant to be run from the repository root. The commands use relative paths only.

Requirements

Use a terminal where ROS 2 Humble is already available.

Check the shell first:

ros2 --help
colcon --help

Install common build tools if needed:

sudo apt update
sudo apt install python3-colcon-common-extensions python3-rosdep

Install package dependencies:

rosdep update
rosdep install --from-paths src --ignore-src -r -y

You also need a desktop session or X server for RViz2.

Build

Build only the ROS 2 packages under src:

colcon build --symlink-install --base-paths src
source install/setup.bash

Use a smaller rebuild while editing the demo:

colcon build --symlink-install --base-paths src \
  --packages-select plan_env exploration_manager
source install/setup.bash

Run The Demo

Start the pillar demo with RViz2:

source install/setup.bash
ros2 launch exploration_manager racer_pillar.launch.py

Run without RViz2:

source install/setup.bash
ros2 launch exploration_manager racer_pillar.launch.py rviz:=false

If RViz2 has rendering problems, force software rendering:

source install/setup.bash
LIBGL_ALWAYS_SOFTWARE=1 ros2 launch exploration_manager racer_pillar.launch.py \
  rviz_gl_vendor:=mesa

Start Exploration

The launch waits for a goal on move_base_simple/goal.

In RViz2:

1. Wait for the map and display tree to load.
2. Select 2D Goal Pose.
3. Click near the center of the map and drag to set the heading.

From another terminal:

source install/setup.bash
timeout 10 ros2 topic pub -r 10 move_base_simple/goal \
  geometry_msgs/msg/PoseStamped \
  "{header: {frame_id: world}, pose: {position: {x: 0.0, y: 0.0, z: 1.0}, orientation: {w: 1.0}}}"

The repeated publish gives all four exploration nodes time to receive the same start goal.

Expected Output

The demo starts:

• map_generator for the pillar map.
• Four exploration_node processes.
• Four traj_server processes.
• Four poscmd_2_odom lightweight simulator processes.
• Four pcl_render_node local sensing processes.
• Four odometry visualization nodes.

When exploration finishes, each exploration node prints No grid. The trajectory servers also print one summary line per drone:

Drone <id>, [<time>,<length>,<velocity>,<energy>], [time, length, vel, energy]

A typical pillar run finishes in about 40-60 s, but timing and path length vary because planning and map updates are not deterministic.

Benchmark

Run repeated clean headless trials and write CSV/log output under benchmark_results:

source install/setup.bash
python3 tools/benchmark_pillar.py --runs 5 --timeout-sec 120 \
  --output benchmark_results/pillar_runs.csv \
  --log-dir benchmark_results/logs

For a longer run:

source install/setup.bash
python3 tools/benchmark_pillar.py --runs 10 --timeout-sec 180 \
  --output benchmark_results/pillar_runs_10.csv \
  --log-dir benchmark_results/logs_10

The CSV includes exploration time, total path length, wall time, completion mode, and per-drone coverage percentages.

Useful Launch Arguments

rviz:=true
rviz:=false
rviz_gl_vendor:=mesa
coverage_metrics:=true
coverage_report_interval_sec:=1.0
show_grid_text:=true

HGrid debug text labels are hidden by default. Set show_grid_text:=true when you want the numbered grid IDs in RViz2.

Example with coverage logs enabled:

source install/setup.bash
ros2 launch exploration_manager racer_pillar.launch.py \
  coverage_metrics:=true coverage_report_interval_sec:=1.0

Troubleshooting

If ros2 cannot find exploration_manager, source the workspace again:

source install/setup.bash

If colcon reports duplicate package names, make sure the build command uses --base-paths src.

If exploration does not start, publish the goal again:

source install/setup.bash
timeout 10 ros2 topic pub -r 10 move_base_simple/goal \
  geometry_msgs/msg/PoseStamped \
  "{header: {frame_id: world}, pose: {position: {x: 0.0, y: 0.0, z: 1.0}, orientation: {w: 1.0}}}"

If RViz2 opens but the scene is blank, check that demo topics are present:

source install/setup.bash
ros2 topic list | grep -E "map_generator|sdf_map|planning_vis|odom_visualization"

Stop a run with Ctrl-C in the launch terminal. Start a fresh terminal, source install/setup.bash, and launch again for a clean interactive run.