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The rigid body attitude stabilization problem with constrained control inputs has been studied by many researchers. However, if perfect eigen-axis rotation in rest to-rest maneuvers is also desirable, the control design problem becomes more challenging and, to the best of the authors’ knowledge, has not yet been addressed. In this letter, an anti-windup compensation approach to this problem is developed. A nonlinear dynamic inversion control is used to obtain satisfactory unconstrained performance and this is supplemented by an anti-windup compensator when constraints are encountered. The compensator provides global L2 performance under reasonable conditions. A highlight of the approach is that the anti-windup compensator can have a nonlinear structure, giving flexibility in the choice of its parameters. Simulation results demonstrate the effectiveness of the proposed scheme as well as the performance improvement achieved using a compensator with state-dependent parameters. 

In this paper, the problem of anti-windup compensator (AWC) design for implementation in the autonomous guidance and control of quadrotors is addressed. The flight environment contains obstacles with no prior knowledge of their locations. Instead, obstacles location are determined in real time, and the locations are used by a guidance algorithm for avoidance. Wind disturbances are also considered since their presence can potentially result in saturation of the propellers. When this occurs, the flight can become unstable, leading to a crash. Designing an AWC to mitigate the effects of saturation in the control system of a quadrotor can be a challenging task due to the heavy couplings and complex nonlinear dynamics. For this reason, we propose a new structure to design a static AWC-based control system to solve this problem. The effectiveness of the proposed theoretical results are verified by comparing results from simulation experiments. 

This letter considers the problem of trajectory tracking for quadrotors operating in wind conditions that result in propeller thrust saturation. To address this problem, an anti-windup compensator (AWC) is developed to reduce the tracking performance degradation and destabilizing effects from thrust saturation. Relationships are derived showing how the tracking error and AWC states are influenced by the wind disturbance and saturation, and how the influences depend on the controller and AWC gains. As a result, these gains can be tuned to achieve desired performance levels. Simulation results are presented to validate the effectiveness of the proposed method. 

In this paper, the problem of anti-windup compensator (AWC) design for guidance and control of quadrotors in an unknown environment is addressed. Quadrotors can be affected by disturbances (such as wind), which potentially result in saturation of the propellers. When saturation occurs, the flight can become unstable, leading to a crash. On the other hand, designing an AWC to mitigate the saturation effects in the control system of a quadrotor can be a challenging task due to the heavy couplings and complex nonlinear dynamics. For this reason, we propose a new structure to design an AWC-based control system to solve this problem. Simulation results are presented in three cases: 1-without saturation, 2-with saturation - without AWC, 3-with saturation - with AWC. The effectiveness of the proposed theoretical results are verified by comparisons.