Nonlinear Dynamics and Control Lab

Coordination, Steering and Deconfliction for Unmanned Air Vehicles

(The Boeing Company)

The focus of the work in this project is to develop coordinated control algorithms for formations of UAVs (Unmanned Air Vehicles) that allow the formation to track single or multiple targets while preventing collisions.  Successful tracking of a single target will be characterized by the centroid of the group tracking the position of the target, and tracking of multiple targets will be characterized by both the centroid of the group tracking the centroid of the set of targets and the footprint of the group covering the set of targets.  The relative locations of the vehicles within the group is prespecified using potential functions, and leader-follower techniques are used to guarantee each vehicle maintains its specified relative location.  Further, to ensure safe operation of the group, deconfliction techniques are being developed to prevent collisions.

The relative positions of the vehicles in the group will be specified using an application of spatial density functions.  Density functions, which are a type of potential function, can be used to place vehicles in configurations such as linear or planar shapes with given boundary.  Further, with density functions the intervehicle spacing can be modulated and time-varying to allow more vehicles in some areas and fewer in others, such as would be desired for greater sensor coverage in some areas.

To accommodate realistic aircraft dynamics with angular rate and speed bounds, we are currently applying a version of averaging theory to the dynamics of the aircraft.  Specifically, by applying state and time dependent amplitude-modulated sinusoidal control to nonholonomic vehicle models with fixed forward velocity, a class of controllable (but not STLC) systems emerges.

UAV Coordination graph model