A 3D Reactive Navigation Method for UAVs in Unknown Tunnel-like Environments

Many applications require unmanned aerial vehicles (UAVs) to autonomously navigate through unknown tunnel-like environments such as caves exploration, dam penstocks inspection, exploration and mapping in underground mines, etc. The design of the overall navigation strategy can be very challenging to ensure a collision-free motion advancing through the tunnel especially when considering a three-dimensional (3D) workspace. Hence, this work proposes a 3D collision-free control strategy for UAVs to ensure safe navigation through unknown tunnel-like environments. This strategy is reactive as it relies only on light processing of recent sensors observations to generate reflex-like reactions. The strategy is evaluated using computer simulations assuming a realistic sensing model, and good results were obtained.