High performance L1 adaptive take-off and landing controller design for fixed-wing UAV

For Take-off and Landing Controller of Fixed-wing Unmanned Aerial Vehicles (UAV) in the presence of strong disturbances and unknown ground effects, a High Performance L
₁
Adaptive Control (HPL
₁
AC) method is proposed in this paper. HPL
₁
AC is based on a combination of L
₁
adaptive controller and Robust Pole Assignment Controller (RPAC), where RPAC is utilized to stabilize the closed-loop system and L
₁
adaptive controller is adopted to guarantee control performance under strong disturbances and unknown ground effects. In addition, BGF (Bounded-Gain Forgetting) estimator is introduced to realize time-varying adaption for adaptive gain matrix. Finally, simulation results show that the proposed HPL
₁
AC Take-off and Landing Controller obtains desirable transient performance and robustness for short period dynamics of Medium-Size Transport UAV.