Abstract
A number of recent papers have considered trajectory tracking control design for unmanned aerial vehicles (UAVs). In practice, an autonomous vehicle has access only to absolute measurements of non-inertial variables such as linear acceleration and angular velocity along with local measurements of inertial quantities such as position, velocity and orientation. Expressing the dynamics of a typical system in body fixed frame coordinates introduces dynamic coupling that appears to destroy the simple structure of the inertial equations. In this paper it is shown that the inherent passivity-like properties of the underlying mechanical system may be exploited to obtain the Lyapunov control design for the more general system equations expressed in the body fixed frame of an unmanned aerial vehicle. This avoids a possibly difficult and highly non-robust state reconstruction that would be necessary before existing control designs could be applied.