“…The problem of formulating a stabilizing feedback law in non-Euclidean spaces, such as SO(3) and SE(3), has been addressed in several references, namely [Malisoff et al, 2006, Chaturvedi and McClamroch, 2006, Fragopoulos and Innocenti, 2004, Bhat and Bernstein, 2000, where the analysis of the topological properties of the SE(3) manifold provides important guidelines for the design of observers. Nonlinear attitude observers motivated by aerospace applications are found in [Salcudean, 1991, Thienel andSanner, 2003], yielding global exponential convergence of the attitude estimates in the Euler quaternion representation.…”