New Gazebo Plugin Simulates Spray Painting with Ray-Cast and Particle Effects

Topguns837 has released gz_sim_spray_painting_plugin, an open-source Gazebo Harmonic system plugin that fills a long-standing gap in robotic spray painting simulation. The plugin attaches a spray nozzle to any robot link and fires a cone of rays every simulation step. Wherever a ray hits a surface, a colored disc is placed flush against it — working on any geometry from simple boxes to complex vehicle meshes like the Prius used in the demo. An optional particle emitter creates the visual mist of a real spray gun, which can be disabled via an SDF flag (<enable_particle_emitter>false</enable_particle_emitter>) for headless simulations or ML training. The spray ON/OFF signal is a standard Gazebo transport Boolean topic (default /spray_paint/trigger), easily bridged to ROS 2 with ros_gz_bridge.

The plugin is fully configurable through SDF parameters: <cone_half_angle_deg> (default 15°), <cone_max_range> (default 1 m), <spray_color> (RGBA, default red). Integration requires only a single plugin block in any URDF or SDF link. The repository includes four demo worlds (demo_car, demo_cube, demo_cylinder, demo_ellipsoid) and a complete Docker setup — no local ROS 2 or Gazebo install needed. The startScript.sh handles Docker build, code build, and simulation launch via an interactive menu. Built with ROS 2 Humble, Gazebo Harmonic, and C++17, the plugin is ready for industrial robotics painting, coating, and surface-coverage tasks. The developer welcomes feedback and contributions via GitHub Issues.