  We address the problem of attitude stabilization of a rigid body, in which
neither the angular velocity nor the instantaneous measurements of the attitude
are used in the feedback, only body vector measurements are needed. The design
of the controller is based on an angular velocity observer-like system, where a
first order linear auxiliary system based directly on vector measurements is
introduced. The introduction of gain matrices provides more tuning flexibility
and better results compared with existing works. The proposed controller
ensures almost global asymptotic stability. The performance and effectiveness
of the proposed solution are illustrated via simulation results where the gains
of the controller are adjusted using non linear optimization.
