Disturbance observer-based control for consensus tracking of multi-agent systems with input delays from a frequency domain perspective

The consensus tracking controller design of multi-agent systems with diverse input delays is studied in this paper. A universal block diagram is established to describe the linear multi-agent systems based on transfer functions. The stabilization of the whole system is decomposed into the zero steady-state error control problem of each independent agent. A sufficient and necessary condition is accordingly deduced to impose on each controller. Based on the H2 performance index of each subsystem, both the optimal consensus controller and disturbance observer (DOB) are derived analytically. The distributed H2 DOB-based consensus controller can not only achieve consensus tracking for the reference input, but also reject the effects of external disturbance and model uncertainty. Some simulations are performed to illustrate the validity of the proposed design approach.