Some features satellite attitude control using quaternions

Algorithms using the kinematics equations in quaternions are widely used in the attitude control systems of modern spacecraft, primarily microsatellites. They ensure large-angle rotations and avoidance of singularity points characteristic of Euler-Krylov angles. However, the specificity of single quaternions as attitude representation parameters can create an "unwinding effect" in the control system, when turning the spacecraft to a desirable position is not performed by the shortest path and increases the electricity consumption, that is limited on board. This work, summarizing known publications, illustrates the causes of this effect and demonstrates a simple algorithm for its prevention. The effectiveness of this approach is shown on the MATLAB platform numerical simulation examples of the microsatellite control system with reaction wheels and a PD controller.