Signal-based self-organization of a chain of UAVs for subterranean exploration
This addresses the challenge of subterranean exploration for robotics applications, but it is incremental as it builds on existing distributed coordination methods.
The paper tackles the problem of maintaining radio connectivity for miniature multi-rotor UAVs in subterranean environments by introducing U-Chain, a distributed algorithm that coordinates a chain of robots using signal quality and optic flow sensors, achieving experimental validation with 3 real quadrotors.
Miniature multi-rotors are promising robots for navigating subterranean networks, but maintaining a radio connection underground is challenging. In this paper, we introduce a distributed algorithm, called U-Chain (for Underground-chain), that coordinates a chain of flying robots between an exploration drone and an operator. Our algorithm only uses the measurement of the signal quality between two successive robots as well as an estimate of the ground speed based on an optic flow sensor. We evaluate our approach formally and in simulation, and we describe experimental results with a chain of 3 real miniature quadrotors (12 by 12 cm) and a base station.