Controller Structures for Parallel Redundant Failure Tolerant Control Systems

As controllers, and particularly digital controllers, are increasingly being used in expensive and/or critical applicants, failure tolerance becomes an important issue. Several researchers have looked at problems concerning transducer failures and using redundancy to improve fault tolerance. In this paper, tolerance to failures of the control hardware are considered, with particular emphasis on controller structures Which correctly allow for multiple parallel controllers to be implemented. In particular, an internally stable, parallel redundant controller structure is given for MIMO linear controllers.