Visualization

Cubs2 provides custom RViz2 panels for simulation control and telemetry display.

RViz Panels

Video Panel

Low-latency video streaming using GStreamer.

Features:

  • Direct rendering (no ROS image topic overhead)

  • Multiple input sources (USB, RTSP, UDP)

  • H.264 and MJPEG support

  • Custom pipeline configuration

Setup:

  1. Add panel: Panels → Add New Panel → cubs2::VideoPanel

  2. Select source from dropdown

  3. Click “Connect”

Predefined Sources:

  • Test Pattern - SMPTE color bars

  • USB Camera - /dev/video0

  • UDP H.264 - Port 5600

  • UDP MJPEG - Port 5600

  • RTSP Stream - Network camera

Custom Pipeline:

Enter GStreamer pipeline string:

v4l2src device=/dev/video1 ! video/x-raw,width=1280,height=720

Joy Panel

Virtual joystick for manual control.

Controls:

  • Left stick: Throttle (Y), Rudder (X)

  • Right stick: Pitch (Y), Roll (X)

  • Trim buttons: Fine-tune neutral positions

  • Enable checkbox: Activate/deactivate

Tips:

  • Disable when using physical gamepad

  • Spring-back to center on release

  • Displays external control when disabled

Sim Panel

Simulation configuration and control.

Controls:

  • Reset: Return to initial conditions

  • Pause: Freeze simulation

  • Speed: 0.25x to 100x real-time

  • Timestep: 0.001s to 0.1s

Real-time Adjustment:

All changes take effect immediately without relaunch.

HUD Panel

Flight telemetry heads-up display.

Displays:

  • Artificial horizon (pitch/roll)

  • Roll indicator arc

  • Altitude (meters)

  • Airspeed (m/s)

Usage:

Automatically updates from /sportcub/pose and /sportcub/velocity.

3D Visualization

Aircraft Model

URDF model with visual mesh from cubs2_description.

View Options:

  • Wireframe

  • Solid with texture

  • Collision geometry

Force Visualization

Enable with launch argument:

ros2 launch cubs2_bringup sim.xml show_forces:=true

Shows:

  • Lift vector (blue)

  • Drag vector (red)

  • Thrust vector (green)

Path Display

Planned path shown as:

  • Green line - Future trajectory

  • Red line - Past trajectory (breadcrumbs)

Racecourse

Gates displayed as:

  • Colored spheres at positions

  • Yellow highlight for current target

  • Transparent rings (if available)

Camera Control

Follow Mode

Camera automatically tracks aircraft:

  1. In RViz: Views → Type → ThirdPersonFollower

  2. Set target frame: vehicle

  3. Adjust distance and angle

Fixed Views

Common viewpoints:

  • Top-down: Good for path visualization

  • Chase: Behind and above aircraft

  • Cockpit: First-person view (if model supports)

Recording

Record camera trajectory:

# Record
ros2 bag record /camera/pose

# Playback
ros2 bag play camera_recording.bag

Configuration

RViz Config

Default layout: cubs2_rviz/config/cubs2.rviz

Customize:

  1. Arrange panels and displays

  2. Save: File → Save Config As...

  3. Load: ros2 launch cubs2_bringup viz.xml rviz_config:=/path/to/config.rviz

Topics to Display

Useful additional topics:

  • /tf - Transform tree

  • /odometry - Position trail

  • /imu - IMU axes

  • /path - Planned trajectory

Troubleshooting

Video Panel

No video:

  • Check GStreamer: gst-launch-1.0 videotestsrc ! autovideosink

  • Verify camera: ls /dev/video*

  • Check RViz terminal for errors

Lag/stutter:

  • Reduce resolution

  • Use H.264 encoding

  • Prefer wired connection

Performance

Low FPS:

  • Disable unused displays

  • Reduce point cloud density

  • Lower simulation rate

High CPU:

  • Disable shadows

  • Reduce mesh complexity

  • Use simpler materials

See Also