Geometric L1 Adaptive Attitude Control for a Quadrotor Unmanned Aerial Vehicle

Abstract

In this paper, we study the quadrotor UAV attitude control on SO(3) in the presence of unknown disturbances and model uncertainties. L1 adaptive control for UAVs using Euler angles/quaternions is shown to exhibit robustness and precise attitude tracking in the presence of disturbances and uncertainties. However, it is well known that dynamical models and controllers that use Euler angle representations are prone to singularities and typically have smaller regions of attraction while quaternion representations are subject to the unwinding phenomenon. To avoid such complexities, we present a Geometric L1 adaptation control law to estimate the uncertainties. A model reference adaptive control approach is implemented, with the attitude errors between the quadrotor model and the reference model defined on the manifold. Control laws for the quadrotor and reference models are developed directly on SO(3) to track the desired trajectory while rejecting the uncertainties. Control Lyapunov function based analysis is used to show the exponential input-to-state stability of the attitude errors. The proposed L1 adaptive controller is validated using numerical simulations. Preliminary experimental results are shown comparing a geometric PD controller to the geometric L1 adaptive controller. Experimental validation of the proposed controller is carried out on an Autel X-star quadrotor.

Performance, Precision, and Payloads: Adaptive Nonlinear MPC for Quadrotors

“…Typically, this is done using a linear reference model to specify the desired behavior, however this can lead to unrealistic desired dynamics which cannot be achieved by the real system. Adaptive control has successfully demonstrated accurate trajectory tracking using quadrotors in several works [27][28][29][30]. However, the maneuvers conducted are typically simple step inputs, or slow speed circles which do not exploit the inherent agility of the quadrotor platform.…”

Finite-Time Attitude Control With Chattering Suppression for Quadrotors Based on High-Order Extended State Observer

“…=  e (12) And define the sliding mode variable as  are positive controller gains to be set. Theorem 3: For the relevant quadrotor attitude dynamics (2), along with HESO design (9), sliding mode surface (13) and proposed control law (15), supposing all assumptions are met, then the estimation error 3,i e and sliding mode variable i s are both UUB.…”

“…Researches on attitude control schemes for quadrotors have conducted abundant of advanced approaches in recent years. For instance, backstepping control [9]- [10], active disturbance rejection control [11]- [12], sliding mode control (SMC) [13]- [14] and the like.…”

USDE-Based Continuous Sliding Mode Control for Quadrotor Attitude Regulation: Method and Application

“…However, because of the existence of inherent model nonlinearities, parametric uncertainties as well as extraneous wind disturbances, how to develop an effective attitude controller for quadrotors is still an ongoing issue in engineering practices. Focusing on this, abundant of innovative control policies have been conducted for quadrotor attitude tracking, to name just a few, adaptive control [11]- [12], backstepping control [13], sliding mode control [14]- [15] and so on.…”