Model‐assisted extended state observer and dynamic surface control–based trajectory tracking for quadrotors via output‐feedback mechanism

Abstract

Summary In this paper, an output‐feedback trajectory tracking controller for quadrotors is presented by integrating a model‐assisted extended state observer (ESO) with dynamic surface control. The quadrotor dynamics are described by translational and rotational loops with lumped disturbances to promote the hierarchical control design. Then, by exploiting the structural property of the quadrotor, a model information–assisted high‐order ESO that relies only on position measurements is designed to estimate not only the unmeasurable states but also the lumped disturbances in the rotational loop. In addition, to account for the problem of “explosion of complexity” inherent in hierarchical control, the output feedback–based trajectory tracking and attitude stabilization laws are respectively synthesized by utilizing dynamic surface control and the corresponding estimated signals provided by the ESO. The stability analysis is given, showing that the output‐feedback trajectory tracking controller can ensure the ultimate boundedness of all signals in the closed‐loop system and make the tracking errors arbitrarily small. Finally, flight simulations with respect to an 8‐shaped trajectory command are performed to verify the effectiveness of the proposed scheme in obtaining the stable and accurate trajectory tracking using position measurements only.

Disturbance Observer-Based Control for Trajectory Tracking of a Quadrotor

“…where I 2 ∈ R 2×2 and I 3 ∈ R 3×3 are identity matrices, is a positive constant, and 2 1 /(2 )I 2 + 1/2Ψ + Γ * 1 , and Γ −1…”

“…A quadrotor requires position and attitude control for autonomous flight. However, it is difficult to design an appropriate controller because the quadrotor model is underactuated and has strong nonlinear couplings between its dynamic states [2]. Furthermore, robustness against disturbances such as wind gusts during the operation of the quadrotor is essential for control performance [3].…”

Robust fixed time controller with motor dynamics and composite disturbances for a quadrotor unmanned aerial vehicle

“…21 And it is also widely used in quadrotor control to compensate the adverse impact to the system caused by disturbance. [22][23][24][25][26] Xingling Shao et al 27 present an ESO-based robust dynamic surface trajectory tracking controller for a quadrotor subject to parametric uncertainties and external disturbances. ESO is constructed to estimate online the unmeasurable velocity states and lumped disturbances.…”

Nonlinear control with integral sliding properties for circular aerial robot trajectory tracking: Real‐time validation

“…The application of SMCs for UAVs has been addressed by some works to provide system robustness. For instance, other works used sliding mode observers to obtain state signals, which were then introduced to the control loop. In the work of Dong et al, a supertwisting SMC with adaptive gains was developed for a UAV with 3 degrees of freedom.…”