This paper analyzes a fault-tolerant, microprocessor-based controller for an electric wheelchair. Two-candidate architectures are considered, including reconfigurable duplication and standby sparing. The difference in the reliability and safety of the two candidates is determined through the use of Markov models. Safety is paramount in the wheelchair application because of the need to protect the physically disabled wheelchair user; reliability by itself is insufficient for selecting an appropriate architecture in this application. The results show that reconfigurable duplication is safer than standby sparing even though standby sparing is more reliable. Because of the better safety, reconfigurable duplication is the prefered approach for the wheelchair application. Safety is extremely important in the selection of a fault-tolerant architecture for the electric wheelchair control system. Standby sparing provides a conceptually simple approach that achieves a higher reliability than reconfigurable duplication. However, reconfigurable duplication has a higher safety for a given fault coverage. Because of the need for safety in the electric wheelchair control system, reconfigurable duplication is the selected approach.
Reliability and safety analysis of a fault-tolerant controller
Zuverlaessigkeits- und Sicherheitsanalyse eines fehlertoleranten Steuerteils
IEEE Transactions on Reliability ; 35 , 4 ; 355-362
1986
8 Seiten, 12 Bilder, 14 Quellen
Aufsatz (Zeitschrift)
Englisch
FEHLERTOLERANTES SYSTEM , STEUERWERK , MIKROPROZESSOR , SYSTEMZUVERLAESSIGKEIT , SICHERHEIT , ANALYSIS (MATHEMATIK) , ELEKTROANTRIEB , MARKOV-PROZESS , BEREITSCHAFTSBETRIEB , REDUNDANZ , ZUVERLAESSIGKEIT , BLOCKDIAGRAMM , SYSTEMVERGLEICH , VERGLEICHSSCHALTUNG , KOMPENSATIONSMESSUNG , SYSTEMANALYSE , MATHEMATISCHES MODELL , SELBSTUEBERWACHUNG , AUSFALLRATE , AUSFALLZEIT , MATRIX , ROLLSTUHL , MARKOV-MODELL
A hardware and software fault tolerant safety controller
AIAA | 1989
|Fault -Tolerant System Reliability Modeling /Analysis
AIAA | 1977
|Fault tolerant system reliability modeling/analysis
AIAA | 1976
|A fault-tolerant 1750A engine controller
AIAA | 1986
|