An accurate low-cost capacitive absolute angular-position sensor with a full-circle range

Author

Li, Xiujun ; Meijer, Gerard C M ; de Jong, Gerben W. ; Spronck, Jo W.

Author_Institution

Dept. of Electr. Eng., Delft Univ. of Technol., Netherlands

Volume

45

Issue

2

fYear

1996

fDate

4/1/1996 12:00:00 AM

Firstpage

516

Lastpage

520

Abstract

A novel high-performance smart capacitive angular-position sensor with a full-circle measurement range is presented. The sensor is mainly composed of three parts: the capacitive sensing element, a signal processor and a microcontroller. Using an appropriate algorithm, the effects of the main undesired influences are eliminated or strongly reduced. The measurement range covers the full-circle range (360°). The structure of the sensing element is optimized to reduce the influence of the electric-field-bending effect and the mechanical errors. The signal processor has a multicapacitance input and a single period-modulated output, and includes a nearly linear capacitance/period converter. The microcontroller acquires output data from the processor, calculates the positions and optionally communicates with the outside digital world. The resolution of the smart capacitive angular-position sensor is 1.5 arcsec, and the nonlinearity is less than ±58 arcsec over the 0-360° range for a measurement time of 140 ms

Keywords

angular measurement; capacitance measurement; computerised instrumentation; digital signal processing chips; electric sensing devices; intelligent sensors; measurement errors; microcontrollers; position measurement; absolute angular-position sensor; accurate low-cost; algorithm; capacitive sensing element; capacitive sensor; error effects; full-circle measurement range; high-performance smart sensor; microcontroller; multicapacitance input; multisegment electrode structure; nearly linear capacitance/period converter; nonlinearity; signal processor; single period-modulated output; Capacitance measurement; Capacitive sensors; Electrodes; Energy resolution; Intelligent sensors; Mechanical sensors; Microcontrollers; Position measurement; Signal processing; Signal processing algorithms;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/19.492778

Filename

492778