Stochastic Analysis of a System with Redundant Robots, One Built-in Safety Unit, and Common-Cause Failures

  • B. S. Dhillon
  • Zhijian Li


This paper presents reliability and availability analyses of a mathematical model representing a robot-safety system having n-redundant robots and one built-in safety unit with common-cause failures. At least k robots must function successfully for the overall robot system success. The system failure rates and the partially failed system repair rates are assumed constant and the failed system repair time is assumed arbitrarily distributed. Markov and supplementary variable methods were used to develop generalized expressions for state probabilities, system availabilities, reliability, and mean time to failure. Some plots of these expressions are shown.

Key words

availability common-cause failures reliability repair robot safety system 


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringUniversity of OttawaOttawaCanada

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