Title :
A study of failure models in feedback control systems
Author :
Cunha, João Carlos ; Maia, Ricardo ; Rela, Mário Zenha ; Silva, João Gabriel
Author_Institution :
Dept. Eng. Inf. e de Sistemas, Inst. Superior de Eng. de Coimbra, Portugal
Abstract :
Feedback control systems have a peculiar behavior that allows them to compensate for disturbances in the controlled application. This paper investigates whether this resilience also extends to disturbances originating from faults in the controller itself. The question of what kind of failure model is more effective in this type of system is addressed, with three different models being studied: arbitrary failure, fail-silent, and fail-bounded. The study is conducted essentially by experimental fault injection in the controller of one of the best known and most demanding of the benchmarks used in the control systems area: an inverted pendulum. The considered failure models are compared according to criteria based on the quality of the control action. Other insights gained from the experiments made are described, for instance on how to significantly increase dependability at a very low cost in the feedback controllers, and on the need for a different kind of real-time scheduling algorithm.
Keywords :
compensation; control system analysis; controllers; failure analysis; feedback; real-time systems; scheduling; arbitrary failure; control action quality; controlled application; controller faults; dependability; disturbance compensation; fail-bounded behaviour; fail-silent behaviour; failure models; fault injection; feedback control systems; feedback controllers; inverted pendulum; real-time scheduling algorithm; resilience; Application software; Computer errors; Control systems; Costs; Delay; Error correction; Feedback control; Hardware; Process control; Resilience;
Conference_Titel :
Dependable Systems and Networks, 2001. DSN 2001. International Conference on
Conference_Location :
Goteborg, Sweden
Print_ISBN :
0-7695-1101-5
DOI :
10.1109/DSN.2001.941416