Patent · US Expired

Control systems

US4130241A · kind A · utility

52Cited by
8References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 10, 1977
Grant dateDec 19, 1978
Priority date
Expiry dateMar 10, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05D1/0077
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A quadruplex, double-failure survival, fly-by-wire aircraft control system includes two monitor lanes whose outputs are consolidated with those of the four main control lanes to drive the aircraft control-surfaces by hydraulic rams via individual spool-valve actuators. Nominally-identical sets of pilot's-demand, instrument, and position-feedback signals are derived independently for the four lanes respectively, and digital representations of all these are exchanged between the control lanes for the selection of their mean or median values by digital processors that also serve to compute the control outputs of the lanes from the selected values. The sets of signals supplied to one pair of the four lanes are reversed in sense compared with the sets supplied to the other pair so as to ensure that the same digitally-encoded data is represented differently in the different pairs and the possibility of a context-dependent failure occurring simultaneously in both pairs is thereby avoided. The outputs of the control lanes are amalgamated to provide intermediate-value inputs to the monitor lanes. An alternative monitored-duplex single-failure survival fly-by-wire system has two control lane…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.