Acrobatic Quadrotor Flight
SE(3) geometric control with L1 adaptive augmentation on a Crazyflie 2.1 — zero-radius flips, recovery, and 94% disturbance rejection in ROS 2 simulation.
An SE(3) geometric controller with L1 adaptive augmentation for the Crazyflie 2.1 micro quadrotor, implemented as a ROS 2 + Gazebo Harmonic simulation stack with a full ROS–Gazebo bridge (odometry, IMU, pose, and motor-command topics).
Why geometric control
Euler-angle attitude controllers hit singularities exactly where acrobatics live — near ±90° pitch. The SE(3) controller works directly on the rotation manifold: attitude error is computed from rotation matrices, so a zero-radius flip is just another trajectory rather than a special case. Thrust and moments are computed from geometric position/velocity/attitude errors, with mode switching across hover, minimum-jerk trajectory tracking, flip, and recovery.
Why L1 augmentation
Geometric control assumes the model is right. Real vehicles (and imperfect simulators) have unmodeled drag, thrust mismatch, and external pushes. The L1 adaptive loop estimates the matched disturbance at high rate through a state predictor, and cancels it through a low-pass filter — keeping the adaptation aggressive without exciting high-frequency dynamics. The controller stays a geometric controller; L1 just makes its model assumption true.
Results
| Metric | Result |
|---|---|
| Position-tracking RMSE | 2.2 cm |
| Force-step disturbance rejection | up to 94% |
| Maneuvers | hover, minimum-jerk tracking, zero-radius flip, recovery |