This paper addresses the problem of steering a fleet of UAVs along desired paths while meeting stringent spatial and temporal constraints. A representative example is the challenging mission scenario where the vehicles are tasked to cooperatively execute collision-free maneuvers and arrive at their final destinations at the same time (time-critical operations). In the setup adopted, the vehicles are assigned nominal spatial paths and speed profiles along those. The paths are then appropriately parameterized and the vehicles are requested to execute cooperative path following, rather than open loop trajectory tracking maneuvers. This strategy yields robust behavior against external disturbances by allowing the vehicles to negotiate their speeds along the paths in response to information exchanged over the dynamic inter-vehicle communications network. The paper addresses explicitly the situation where each vehicle transmits its coordination information to only a subset of the other vehicles, as determined by the communications topology. Furthermore, we consider the case where the communications graph that captures the underlying communications topology is disconnected during some interval of time or even fails to be connected at all times. Conditions are given under which the complete time-critical cooperative path-following closed-loop system is stable and yields convergence of a conveniently defined cooperation error to a neighborhood of the origin. Flight test results of a coordinated road search mission demonstrate the efficacy of the multi-UAV cooperative control framework developed in the paper.
Time-Critical Cooperative Path Following of Multiple UAVs over Time- Varying Networks
2011
37 pages
Report
Keine Angabe
Englisch
Aircraft , Navigation Systems , Drones , Flight control systems , Air navigation , Automatic pilots , Closed loop systems , Collision avoidance , Communications networks , Cooperation , Flight testing , Formation flight , Information exchange , Kinematics , Multiagent systems , Time dependence , Complex vehicle dynamics , Control algorithms , Cooperative missions , Cooperative path following , Coordination , Multi-vehicle missions , Multiple vehicle control , Nonlinear control , Path following problem , Stability analysis , Time critical coordination , Time-varying communications topologies , Uav(Unmanned aerial vehicles)
Time-Coordinated Path Following of Multiple UAVs over Time-Varying Networks using L~1 Adaptation
British Library Conference Proceedings | 2008
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