Adaptive quantizer for networked control system

This paper proposes a novel approach for data-compression using Delta-sigma modulator (ΔΣ-M) and applies it to design bit-stream based controllers. An adaptive scheme is introduced to automatically determine the upper and lower boundaries of the quantizer of the ΔΣ-M. The stability condition of the feedback control system with embedded ΔΣ-M is derived analytically based on sliding mode analysis. The effectiveness of the proposed controller is illustrated experimentally by designing hybrid bit-stream based feedback controller to control the position of a D.C. motor. Experimental results from a laboratory prototype illustrate that the adaptive ΔΣ-M with the feedback controller effectively controls the systems while consuming less significant channels interfaces between the measurement device and the controller.