Design and implementation of robust corrective control systems with permanent sensor faults

This paper presents fault diagnosis and fault-tolerant corrective control for a class of asynchronous sequential machines (ASMs). In the considered problem setting, a permanent fault may occur to the sensor in the feedback channel so that the distorted state feedback is forced to be generated after a fault occurrence. We propose a scheme of identifying the permanent sensor fault only by observing the feedback value measured in the form of state bursts. Based on the diagnosis method, we address a novel design algorithm for a state-feedback corrective controller that matches the stable-state behavior of the closed-loop system to that of a reference model, while accommodating the permanent damage to the sensor. Hardware experiments on the field-programmable gate array (FPGA) circuit are provided to demonstrate the applicability of the proposed fault diagnosis and fault-tolerant corrective control methodology.