The paper proposes a technique to estimate the angular velocity of a rigid
body from single vector measurements. Compared to the approaches presented in
the literature, it does not use attitude information nor rate gyros as inputs.
Instead, vector measurements are directly filtered through a nonlinear observer
estimating the angular velocity. Convergence is established using a detailed
analysis of a linear-time varying dynamics appearing in the estimation error
equation. This equation stems from the classic Euler equations and measurement
equations. As is proven, the case of free-rotation allows one to relax the
persistence of excitation assumption. Simulation results are provided to
illustrate the method.Comment: 10 pages, 8 figures. arXiv admin note: substantial text overlap with
arXiv:1503.0287
