  In this paper we investigate the problem of using a UAV to provide current
map information of the environment in front of a moving ground vehicle. We
propose a simple coverage plan called a conformal lawn mower plan that enables
a UAV to scan the route ahead of the ground vehicle. The plan requires only
limited knowledge of the ground vehicle's future path. For a class of
curvature-constrained ground vehicle paths, we show that the proposed plan
requires a UAV velocity that is no more than twice the velocity required to
cover the optimal plan. We also establish necessary and sufficient UAV
velocities, relative to the ground vehicle velocity, required to successfully
cover any path in the curvature restricted set. In simulation, we validate the
proposed plan, showing that the required velocity to provide coverage is
strongly related to the curvature of the ground vehicle's path. Our results
also illustrate the relationship between mapping requirements and the relative
velocities of the UAV and ground vehicle.
