Formation Tracking for Nonlinear Uncertain Multi-Agent Systems via Adaptive Output Feedback Quantized Control

This paper studies the distributed output feedback control problem for formation tracking of multi-agent systems with both quantized control and measurement signals. The control and measurement signals are processed by hysteretic quantizers to avoid chattering. The agent dynamics are described by a nonlinear uncertain model with immeasurable states, unmodeled dynamics, and disturbances. To estimate the immeasurable states and solve uncertainties, state observers are designed by utilizing dynamic high-gain technique. With the state observer, a distributed output feedback controller is developed for multi-agent systems by using the quantized measurements of the relative positions of the agents and the quantization effect on the control system is eliminated. The stability analysis proves that the proposed controller can achieve the multi-agent formation tracking, and all the closed-loop signals are bounded. By using the MATLAB/Simulink software, experimental results verifies the effectiveness of the proposed control scheme.