US 7,515,995 B2 · Continuous median failure control system and method

Abstract

A redundant control system including at least three redundant signals is presented. The redundant control system includes a failure circuit associated with each of the redundant signals. The failure circuit generates a failure signal in response to an occurrence of a failure of a corresponding one of the redundant signals. A select circuit is associated with each of the redundant signals. The select circuit is receptive to a default signal associated with the corresponding one of the redundant signals, to the failure signal, and to the corresponding one of the redundant signals. The select circuit selects the default signal when the failure signal indicates a failure of the corresponding one of the redundant signals and selects the corresponding one of the redundant signals when the failure signal does not indicate a failure for the corresponding one of the redundant signals. A median determination circuit is receptive to the default signals selected and the redundant signals selected to determine a median signal indicative of a median of the default signals selected and the redundant signals selected.

Claims15

Dependent claims

A redundant control system including at least three redundant signals, comprising:

at least three failure circuits, each individual one of said at least three failure circuits being associated with an individual one of said at least three redundant signals, said failure circuit generating a failure signal in response to an occurrence of a failure of a corresponding one of the redundant signals;
a first select circuit associated with each of the redundant signals, said first select circuit receptive to a default signal associated with the corresponding one of the redundant signals, to said failure signal, and to the corresponding one of the redundant signals, said first select circuit selecting said default signal when said failure signal indicates a failure of the corresponding one of the redundant signals, said first select circuit selecting the corresponding one of the redundant signals when said failure signal does not indicate a failure for the corresponding one of the redundant signals;
and
a median determination circuit receptive to said default signals selected and the redundant signals selected to determine a median signal indicative of a median of said default signals selected and the redundant signals selected.

1 more element

A redundant control method including at least three redundant signals, comprising:

determining an occurrence of a failure of any one of the redundant signals;
for each of the redundant signals, selecting a default signal associated with the corresponding one of the redundant signals when a failure of the corresponding one of the redundant signals has been determined;
for each of the redundant signals, selecting the corresponding one of the redundant signals when a failure of the corresponding one of the redundant signals has not been determined;
and
determining a median signal of said default signals selected and the redundant signals selected;
wherein said median signal comprises a present median signal of said median signal as determined from present signals of the redundant signals and a previous median signal of said median signal as determined from previous signals of the redundant signals, and further comprising:
combining said present median signal and said previous median signal to provide a difference signal thereof;
and
selecting said difference signal when a failure of said the redundant signals has been determined;
and
selecting a fixed signal when a failure of said the redundant signals has not been determined;
and
combining one of said difference signal selected and said fixed signal selected with said median signal to provide a redundant control system output.

10 more elements

Dependencies are inferred from the claim text.

Continuous median failure control system and method

Life of this patent

Continuous median failure control system and method

Life of this patent

Abstract

Claims15