A new type reliable control system using decision by majority

Presents an idea of reliable sampled data control systems which solves the questions of conventional reliable control without loss of its advantage. The paper considers a situation where three redundant sensors for each output of a controlled object are simultaneously in operation and introduces decision by majority among them. Because only an adopted measured value by the decision by majority is used in the compensator, the performance of the system is expected not to deteriorate when one of the three sensors is out of order. This idea is based on the concept that the decision by majority copes with sensor failures. That is, the measure of failures is taken outside the compensator and does not impose any restrictive conditions on it. As the first step of the study on the idea, the stability against sensor failures is studied in the paper