Distributed quantized state feedback strategy for ensuring predesignated formation tracking performance of networked uncertain nonholonomic multi-robot systems with quantized communication

We present a distributed quantized state feedback approach for ensuring predesignated formation tracking performance of uncertain multiple nonholonomic mobile robots under a band-limited directed network with signal quantization. Under a networked formation control environment, it is assumed that state variables and inputs of all robots are quantized by uniform-hysteretic quantizers and the quantized states of robots are communicated to neighbor robots. A distributed recursive approximation-free design methodology using nonlinear error functions is presented to construct local quantized state feedback trackers that achieve predesignated robust formation tracking performance under quantized communications among robots and unknown nonlinearities of robot dynamics. The proposed local quantized state feedback trackers require only the information of quantized relative positions among robots, without any velocity information of neighbor robots. An analysis strategy for the stability of the proposed formation tracking system is presented using the quantization errors of closed-loop signals. The effectiveness of the distributed quantized feedback design is verified based on the simulation results.