Adaptive Formation Tracking Control of Time‐Varying Euler–Lagrange Systems With Unknown Parameters Under Delayed Switching Topology

This article addresses the formation tracking control problem of multiple Euler–Lagrange systems (ELSs) in the presence of unknown time‐varying parameters, delay and jointly connected switching topologies. A sufficient condition for an average dwell‐time is given based on linear matrix inequalities (LMIs). An adaptive formation control law is developed using the congelation of variables method, Lyapunov–Krasovskii functionals, and backstepping sliding mode controller (SMC). Numerical simulations validate the superior performance of trajectory accuracy, convergence rate, and robustness to communication delays as compared with the classical approach.