Robot Routing Approaches for Convoy Merging Manoeuvres

Autonomous and cooperative guidance strategies for a convoy of electric vehicles in an urban context are a challenging research topic in robotics and intelligent transportation systems. The vehicles that form the convoy eventually will have to leave it to perform a mission and return to the convoy formation once the mission has been accomplished. Nevertheless, the merging maneuvers amongst the convoy and the units returning to it (pursuing unit) is a complex task that involves the determination of the best merging point and the route across the city to reach it. This paper tackles with this routing problem of a robot located in a map and that is trying to join a convoy in constant movement along a peripheral trajectory. We have developed two search strategies able to determine the optimal merging point and the best route to reach it: on one hand we describe a basic solution able to solve the problem when the time spent by the robot travelling along every street of the map is considered to be known and constant. On the other hand, we extended this basic approach to provide a new search strategy that considers uncertainty in travelling times. This increases considerably the complexity of the problem and makes necessary the inclusion of a risk factor that must be considered when determining the best route and the merging point for the maneuver. We also put our search strategies into practice, simulating the behaviour of both, the convoy and the robot trying to joining it, using Player&Stage. In this article we show the results we achieved and that validate both of the aforementioned solutions.

keywords: Robotic route planner, optimal meeting point, merging convoy maneuver, dynamic programming, uncertainty travelling time