Relay-based autotuning for quadrotor attitude and rate control

This work presents a relay-based identification approach to derive linear models of a quadrotor's attitude and rate dynamics, using the Crazyflie 2.1 UAV mounted on a gimbal structure. These models are used to fine-tune the PID controllers at these levels by applying the SIMC and AMIGO tuning PID rules. An event-based control strategy with an adaptive threshold is also implemented to optimize computational efficiency while maintaining control performance. Results show that the proposed approach significantly reduces the number of control actions —by up to 98% and 69% for the pitch axis and 96% and 67% for the roll axis— while preserving stability and effectiveness. These findings highlight the potential of relay-based identification and event-based control in improving UAV attitude control, making it well-suited for real-time embedded applications in aerial robotics.