Constrained Dynamic Route Planning for Unmanned Ground Vehicles

Unmanned Ground Vehicles are tasked with negotiating off-road terrain while satisfying certain objectives, such as maintaining cover and concealment and arriving at a phase line by a designated time. The problem is complicated by the fact that the terrain is typically not known completely in advance, rendering pre-planned routes useless if selected passageways are obstructed. In this situation, the UGV must re-plan the route based on the new sensor information acquired, in such a way that it still satisfies the constraints and objectives. This paper presents a dynamic route planner that rapidly re-plans in response to new information. The planner represents some objectives as soft (e.g., maximizing concealment) and others as hard (e.g., arriving at a phase line on time) and optimizes the soft objectives as much as possible while still meeting the hard. The planner was tested on a simulated scout mission requiring a stealthy traverse with a phase line constraint, and the results are presented.