摘要 |
Measurement circuitry for a biaxial inclinometer having electrolytic fluid incorporates a Schmitt trigger for measuring the resistance of each leg of the inclinometer by measuring the frequency output of the Schmitt trigger circuit while each leg is placed across input and output terminals. Switching is accomplished by cycling analog multiplexers as solid-state switches under control of a microprocessor. To minimize net dc current across any leg, legs are periodically reversed in polarity as they are switched into the Schmitt trigger circuit for measurement. Additionally, in the wiring of the switching multiplexers to the inclinometer legs, an additional analog multiplexer is switched to place a low clamp resistance in parallel with each leg not being measured in a cycle, to compensate for leakage current.
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