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Digital Hardware Voter/Monitor Breadboard Development and Evaluation.

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Final rept. 1 Feb-1 Jul 74,

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The development of a digital hardware votermonitor was undertaken to permit this particular concept of a hardware voter collocated with its associated actuator to be evaluated. The votermonitor was developed in breadboard form. The studies and test results accomplished during this program sufficiently defined the characteristics of this design to permit its implementation in flight hardware to be considered. The breadboard design is based on the concept of the breadboards accepting four redundant input signals and selecting the lower algebraic value of the two intermediate-valued inputs as an output. The form of the output is a pulsewidth modulated signal which is obtained by counting up an inverted version of the selected input. The voter also performs a monitor function by comparing the difference between each input and the output to an acceptable tolerance value. Tolerance values are selected and input by the user and can range from 50 to 0.195 percent of the full-scale absolute values of the input signals. After functional bench tests of the breadboard were completed, the unit was integrated with a simulation of an actuator servo loop. This simulation involved analog and digital segments. The continuous components of the loop were simulated by analog equipment, and the four digital inputs required by the voter were created in real time by a digital program.

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  • Aircraft

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