Geometric Active Disturbance Rejection Control of Rotorcraft on SE(3)
with Fast Finite-Time Stability
This article presents a tracking control framework enhanced by an
extended state observer for a rotorcraft aerial vehicle modeled as a
rigid body in three-dimensional translational and rotational motions.
The system is considered as an underactuated system on the tangent
bundle of the six-dimensional Lie group of rigid body motions, S E ( 3 )
. The extended state observer is designed to estimate the resultant
external disturbance force and disturbance torque acting on the vehicle.
It guarantees stable convergence of disturbance estimation errors in
finite time when the disturbances are constant and finite time
convergence to a bounded neighborhood of zero errors for time-varying
disturbances. This extended state observer design is based on a
Hölder-continuous fast finite time stable differentiator that is similar
to the super-twisting algorithm, to obtain fast convergence. A tracking
control scheme that uses the estimated disturbances from extended state
observer for disturbance rejection, is designed to achieve fast
finite-time stable tracking control. Numerical simulations are conducted
to validate the proposed extended state observer and tracking control
scheme with disturbance rejection. The proposed extended state observer
is compared with other existing research to show its supremacy.