Passivity-Based Adaptive Internal Model Attitude Tracking Control of Uncertain Rigid Spacecraft

The problems of a spacecraft attitude tracking and disturbance rejection are considered. Attitude tracking dynamics are formulated with typical Euler-Lagrange form, and a nonlinear controller is designed by combining a passivity-based adaptive method with an internal model. The unknown constant disturbance and inertia uncertainties are estimated online by element-wise adaptive update laws, while the unknown periodic disturbance is compensated by the internal model. Asymptotic stability of the closed-loop system is proved in the Lyapunov framework. A numerical example is also given to validate the theoretical results of this work.