Magnetic satellite detumbling: the b-dot algorithm revisited

The first task a spacecraft attitude control system must perform after separation from the launcher is to detumble the spacecraft, i.e., to bring it to a final condition with a sufficiently small angular momentum. Magnetic control has been used for decades to fulfill this task, typically using the so-called b-dot control law (in all its variants developed and flown through the years). In this paper the b-dot law is reviewed, a novel convergence analysis based on tools from averaging theory and periodic Lyapunov theory is presented and a simulation study is used to illustrate the results.