A Super-Twisting Observer Design for Thrust-Loss Fault Tolerant Control of Quadrotor Vehicles

In this paper, we tackle the thrust loss problem
in a quadrotor unmanned aerial vehicle, by the design of a
super-twisting observer in the body frame, achieving finite-time
convergence. On this basis, we design a super-twisting low-level
controller to track the desired trajectory and compensate for
the loss effects. Then, the acceleration commands are designed,
and the thrust, Euler angles, and angular speeds are computed.
The stability and the finite-time convergence of the resultant
cascade system are studied, and we show the recovery of
the nominal behavior, as well as the weak recovery of the
separation principle. Finally, high-fidelity experimental analyses
are conducted, to evaluate the performance of the proposed
algorithm in the presence of a variety of thrust loss situations.