| 摘要 |
A fringing-field capacitive level sensor comprising an electrically insulating substrate, having a first and a second pattern of conductive capacitance plates plated on the substrate. Each pattern constitutes a fringing-field capacitor having a capacitance the value of which is both dependent on the liquid level and dependent on the dielectric constant of the liquid. The ratio of the two capacitances, however, is proportional to the liquid level and independent of the dielectric constant of the liquid. The fringing-field capacitive liquid level sensor may be used for measurement of liquids of substantially any dielectric constant without requiring full-scale calibration or knowledge of, and calibration for, dielectric constant of the liquid to be measured. A fringing-field inclinometer sensor application is also provided. The inclinometer uses the liquid level sensor in a circular configuration with four quadrant plates providing the angle sensing of liquid in the sensor liquid container. A two-axis fringing-field inclinometer is provided, enabling tilt angle measurements when the inclinometer is initially tilted with respect to the vertical gravity vector. Improved, side-motion-rejection, liquid-filled inclinometers include a second liquid filling the remaining space in the inclinometer; the filling of the remaining space with the second liquid providing a method of increasing the effective length of the equivalent pendulum. The second liquid is less dense, less viscous, than the first liquid, thereby not decreasing the inclinometer response time.
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