Design of Network Rejoin Policy in Multi-UAVs Flying Ad-hoc Network using Finite Time Convergent Position Control Scheme

Multi-unmanned aerial vehicle systems have several advantages compared to one UAV system, which can be better utilized in different applications such as long-distance surveillance, natural disasters, wildlife welfare, and geology exploration. In this article, we focus on designing a network rejoin policy for a disconnected Unmanned aerial vehicle from the Flying adhoc network(FANET). A finite time convergent chattering free continuous control is also proposed to relocate itself to a neighbor UAV (connected to a network) position. A second-order sliding mode control approach is adopted in position control, which is chattering-free. The finite-time convergence analysis of position, altitude and attitude tracking error is presented. The stability proof of the proposed control scheme is provided using Lyapunov stability criteria. The effectiveness of the proposed control scheme and network rejoin policy is presented through numerical simulations. The proposed control scheme is also compared with existing sliding mode-based methods and performance evaluation is also presented in terms of an increasing number of UAVs in the ad-hoc network.