Large-scale Exploration and Mapping with Field Robots
In these projects, we use a team of aerial and ground robots for large scale exploration and mapping.
Applications:
- Casualty detection and triage
- Search and rescue
- Defense
Heterogeneous teams have a synergistic advantage. High-altitude UAVs can fly fast in an obstacle-free environment, and they can observe a wide area of the map thanks to their elevated viewpoint. UGVs can operate for longer periods, approach objects of interest, and use their low vantage point to perform more accurate measurements.
Opportunistic Communications #
Exploration of large-scale environments is challenging as robots have a limited communication range. To overcome this problem, we propose using opportunistic communications, where robots communicate only when good link quality is detected. Robots can also relay messages from other robots, acting as data mules.
Opportunistic communications have a major drawback: robots may become isolated and not share information with other peers. To overcome this problem, our UAV had a dual-purpose role: in addition to performing exploration, it had an active communication role, looking for isolated ground robots to exchange messages.
Learning What to Communicate #
One of the major challenges of large-scale exploration and mapping with robots is deciding what to explore. Different mission specifications require different label sets.
In this work, we explored how a heterogeneous team of air and ground robots can modify their goals based on their mission specifications. We leveraged SPINE to provide the UAV with a list of tasks. The UAV generates a scene graph with the required objects of interest, and provides it to the ground robots. Upon reception of the graph, ground robots use it to pick goals, navigate to them, and validate them.