A Virtual Force Approach for Cooperative Standoff Target Tracking Using Multiple Robots

This paper presents a virtual force approach for cooperative standoff tracking of a stationary target using multiple robots. Each robot is governed by virtual forces, namely, virtual centripetal force, virtual spring forces and virtual drag forces. The virtual centripetal force counteracts the effect of the centrifugal force and ensures each robot orbit the target. The virtual springs make the orbiting radius converge to the desired standoff distance, and ensure the equidistant distribution of all the robots along the orbit. The virtual drag forces prevent oscillation during the convergence. The use of artificial physics makes the approach be based on solid theoretical foundation. Besides, the proposed approach is decentralized and the physical meanings of parameters are definite, which makes it easy to tune in application. The proof of the global stability and convergence are presented. Simulation results demonstrate the effectiveness of the virtual force approach.