Autonomous Control of Micro Aircraft Vehicles Falling Through an Atmospheric Boundary Layer

A trajectory control problem for simple micro air vehicles (MAVs) is introduced and studied. The MAVs are endowed with the ability to estimate their position and velocity and can control their drag coefficient. The objective of this work is to design a control law for the drag coefficient in order to land the MAV close to a desired streamwise location, after being dropped from an airborne carrier at low altitude. We use a simple model-predictive control law, relying on a two-dimensional time-averaged atmospheric velocity field, which is validated on an unsteady three-dimensional representation of an unstratified atmospheric boundary layer. The simulation results show that the proposed control law results in a significant (10-fold) improvement in the accuracy of the streamwise landing point location, with respect to the uncontrolled case. Similar results are obtained when errors are considered in the location of the release point and in the estimate of the mean flowfield.