Multirobot Target Enclosing with Freely Selected Observation Distances

摘要

Tasks such as surveillance, escorting or robotic object interaction benefit from having complete and detailed perception of a target entity, provided by multiple mobile sensors. The ensuing challenge of suitably coordinating the sensor motions for such collective observation is addressed in this paper. In particular, we consider a moving target in 3D space, and focus on achieving prescribed relative viewing angles, which we encapsulate by a default desired enclosing pattern, with respect to this target. The paper contributes a novel control method that makes a team of mobile agents converge to the desired configuration of viewpoints with respect to a point that tracks the target. Relative agent position regulation and target tracking are integrated via a formation-based controller relying on global information that incorporates an optimal pattern rotation. We also introduce flexibility in the team geometry, allowing each agent to select freely, without knowledge of the others, its desired distance to the target. This can allow to, e.g., optimize perception quality and avoid collisions. Notably, we show that even with these distributed adjustments, the team motions remain steady, which contributes to obtaining stable perception and efficient control performance. In addition, each robot can operate on its independent local reference frame. Simulation tests illustrate the presented methodology.