Fuzzy adaptive PID attitude control of quadcopter unmanned aerial vehicle with airborne radar in autonomous flight mode

Abstract This paper studies a fuzzy adaptive PID control method for a quadcopter UAV equipped with an airborne three-coordinate radar operating in autonomous counter-drone mode. A mathematical model of the quadcopter is first established, and a cascade control architecture is adopted in which fuzzy adaptive PID is applied to the outer position control loops to adjust PID parameters online based on the relative attitude and distance deviation detected by the onboard radar. The horizontal position loops generate roll and pitch references tracked by fixed-gain inner PID controllers. Simulation compares outer-loop adaptation with fixed-gain PID and inner-loop fuzzy PID to assess its effect on attitude transients within the cascade. A universe-of-discourse sensitivity analysis is conducted to examine the effect of FIS input domain size on control performance, and a 21-state closed-loop stability verification with Monte Carlo robustness check under parameter uncertainties is presented. An experimental platform consisting of two quadcopters and an STM32-based flight controller is built for validation. The yaw and pitch MAPE values were 0.1235% and 0.1963%, respectively, for the tested trajectory. In addition, dynamic horizontal calibration tests are performed for the airborne radar, and the altitude measurement error characteristics at different ranges are quantitatively analyzed via segmented RMSE, providing empirical support for the sensing link of the countermeasure system.