A control model for the direct parameter approach for spacecraft attitude tracking is presented in this paper. First of all, the spacecraft attitude tracking control model is built up by the error equation of the second-order nonlinear quaternion-based attitude system. A problem of control system stabilization is raised based on the control model. Compared with other control models, the second-order can offer the advantages of noapproximation and clear control states. The basic spacecraft control model has to focus on to the two variables which are angular rate and attitude quaternion, however, the new attitude control problem is only with respect to one variable which is the spacecraft attitude quaternion. Therefore, the second-order model is simpler and clear than basic first-order model.
Accuracy estimation of the technique for reconstructing the spacecraft attitude motion by measurements of its angular rate and Earth magnetic field strength