  Reusable decoys offer a cost-effective alternative to the single-use hardware
commonly applied to protect surface assets from threats. Such decoys portray
fake assets to lure threats away from the true asset. To deceive a threat, a
decoy first has to position itself such that it can break the radar lock.
Considering multiple simultaneous threats, this paper introduces an approach
for controlling multiple decoys to minimise the time required to break the
locks of all the threats. The method includes the optimal allocation of one
decoy to every threat with an assignment procedure that provides local position
constraints to guarantee collision avoidance and thereby decouples the control
of the decoys. A crude model of a decoy with uncertainty is considered for
motion planning. The task of a decoy reaching a state in which the lock of the
assigned threat can be broken is formulated as a temporal logic specification.
To this end, the requirements to complete the task are modelled as time-varying
set-membership constraints. The temporal and logical combination of the
constraints is encoded in a mixed-integer optimisation problem. To demonstrate
the results a simulated case study is provided.
