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We consider methods for the separate determination of the parameters of capacitive transducers according to instantaneous values of transient processes in a measuring circuit, which ensures an increase in the accuracy of the measurements as a result of the use of a multiple-element replacement for the transducer.

This paper presents a single-electrode capacitive sensor using a single-bit second-order incremental delta–sigma architecture. In order to achieve high accuracy in this capacitance-to-digital converter (CDC), the shielding signal and the digitally controlled offset capacitors are used in combination with the delta–sigma CDC. The designed sensor is suitable for capacitive transducers for ±10 pF input range with sub-fF resolution.

In this article, an indirectly heated micro-electrothermal actuator is presented. The actuator has a capacitive sensor monolithically integrated to provide in vivo sensing of the actuator’s displacement. The actuator and sensor are fabricated using the PolyMUMPs process. Electrothermal and thermal-mechanical models of the actuator have been developed. Simulated displacement versus input current reasonably agrees with tested results. The integrated capacitive sensor readout is an indicator for the displacement.

A quartz sensor of small accelerations with a capacitive transducer is designed and produced, allowing one to measure spacecraft accelerations with a resolution of 10–7 m/s2 in the range ±10–1 m/s2. The results of calibration of the sensor by the method of inclinations are presented.

To successfully establish the ELID-grinding, it is important to properly select the electrolytic condition according to grinding conditions. Currently, the selection of electrolytic condition is mainly dependent on the operator’s experience, which is one of difficulties preventing the successful application of ELID technique. In this study, an in-process measurement system of the insulating layer using two gap sensors-a capacitance type and an eddy current type-are developed and the change of the thickness of insulating layer during ELID grinding is detected. Evaluation experiments show the possibility to control the electrolytic condition through the inprocess measurement of the layer status.

Results are presented from theoretical and experimental studies of the effect of the deformation of an extensometric guide on measurements of the capacitance of thin-film capacitive transducers that measure pressure pulsations.

This article discusses the development and testing of a thin-film capacitive transducer for the measurement of pressure pulsations.

A new method to calibrate a probe for charge measurements is proposed in this paper, after reviewing the principle and a calibration method. The new method is suitable to the measurements on a curved surface. Measurements on a 380 kV spacer at atmospheric conditions show the validity of the method.

Results are presented from an experimental study of pressure pulsations inside the precumbustion chamber of a model of a combustion engine. The pulsations are studied with the use of thin-film capacitive transducers.

Dielectrical glass-ceramic materials for capacitive sensors to measure temperature and humidity have been developed. These sensors are suited for temperature measurement between 4.2 and 100 K (low temperature range), but also for temperatures up to 573 K. The measurement of gas humidity is possible between 5 and 95% R.H. The sensors can be used in multicomponent sensor systems under industrial conditions.

Kapazitive Feldsensoren (\(\dot D\)-,D-Sensoren) eignen sich aufgrund ihrer geringen raumlichen Ausdehnung fur die Messung transienter elektrischer Felder und Spannungen bis in den Subnanosekundenbereich. Die Sensoren konnen in leitenden und nichtleitenden Medien eingesetzt werden. Ausgehend von der Signaleinkopplung erfolgt eine Untersuchung des Sensorubertragungsverhaltens mit Fehlerabschatzungen fur Sensoren, deren raumliche Ausdehnung nicht mehr vernachlassigt werden darf. Uberlegungen zur Realisierung und Kalibrierung der Sensoren fur Feld- und Spannungsmessungen werden durch die Darstellung zweier Sensoren fur flussigkeits- bzw. gasisolierte Anordnungen erganzt.

This paper discusses new aspects in the design of horizontal pendulums and gives a description of the construction of a novel horizontal pendulum with capacitive transducer. Functions and characteristics describing the behaviour of the pendulum are also presented.

The VERBAANDERT-MELCHIOR HORIZONTAL PENDULUM, using a capacitive transducer for the tilt measurements, is described. The output sensitivity is about 100 microvolt for 0.001”. Damping is produced by the air-drag during the motion of the pendulum arm. Results of tidal analysis for two one month fifty-days recording in the Underground Laboratory of Geodynamics at Walferdange (Grand-Duchy of Luxembourg) are also given.

On the basis of these investigations and the results obtained it is possible to assume that the above method for measuring the thickness of liquid films in gas flows can be applied in practice for periodic or continuous monitoring and for the maintenance of computed operating conditions in film-type devices, as well as in scientific investigations dealing with the study of the hydrodynamics of thin liquid films.

An analytical relationship of a differential capacitive transducer's error to its dimensions has been obtained. An analysis of this relationship and experimental investigations have shown that it is possible to manufacture such transducers with a considerably large measurement range and a nonlinearity error of the order of 10−5 of the displacement range.

Test results indicate that a linear analog capacitive transducer is suitable for indicating displacements over a wide range with an error not exceeding 2·10−5. The design relationships and formulas provided above can be used for evaluating the structural factors and parameters of the transducer, which affect its precision, and to make the transducer meet given requirements with a minimum of trimming work. A capacitive linear analog converter of displacements into an ac voltage amplitude is a sufficiently simple device which can be widely used in systems requiring precise measurement of large displacements and lengths.