Vibrating-Wire Transducer

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Vibrating-Wire Transducer

 

a transducer that converts pressure, displacement, flow rate, stress, or other quantities into electrical signals (current, voltage, or frequency).

Table 1b. Sponsors of some Soviet and foreign scientific research vessels
VesselSponsorVesselSponsor
Vitiaz’ ...............Academy of Sciences, USSRAkademik Topchiev ...............Academy of Sciences, USSR
Mikhail Lomonosov ...............Academy of Sciences, Ukrainian SSRAkademik Vavilov ...............Academy of Sciences, USSR
  Merkurii ...............GUGMS
Iu. M. Shokal’skii ...............GUGMSVema ...............USA
A. L. Voeikov ...............GUGMSAtlantis II ...............USA
PetrLebedev ...............Ministry of the Shipbuilding IndustryOceanographer ...............USA
  Melville ...............USA
Ob’ ...............Ministry of the Merchant MarineHero ...............USA
  Glomar Challenger ...............USA
Akademik Kurchatov ...............Academy of Sciences, USSRCalypso ...............France
Passat ...............GUGMSJean Charcot ...............France
Kallisto ...............Academy of Sciences, USSRMeteor ...............Federal Republic of Germany
Zaria ...............Academy of Sciences, USSRDiscovery ...............Great Britain
Akademik Knipovich ...............Ministry of FisheriesSars Michael ...............Norway
Evrika ...............Ministry of FisheriesHakuho Maru ...............Japan
Odissei ...............Ministry of FisheriesUmitakaMaru ...............Japan
Akademik Arkhangel’skii ...............Ministry of GeologyGeneral San Martin ...............Argentina
Poisk ...............Ministry of GeologyKosmonavt lurii Gagarin ...............USSR
Professor Bogorov ...............Academy of Sciences, USSRAkademik Sergei Korolev ...............USSR
Akademik A. Kovalevskii ...............Academy of Sciences, Ukrainian SSRKosmonavt Vladimir 
  Komarov ...............USSR
Professor Dobrynin ...............Academy of Sciences, USSRGeneral Vandenberg ...............USA
Morskoi geofizik ...............Academy of Sciences, USSRRedstone ...............USA
Valerian Uryvaev’ ...............GUGMS ...............American MarinerUSA
G. Iu. Vereshchagin ...............Academy of Sciences, USSR  

The sensing element in a vibrating-wire transducer consists of one or more taut tungsten or steel wires. The operation of the transducer is based on the dependence of the wire’s natural vibration frequency f0 on the wire’s length I, mass m, and tension F (or mechanical stress σ or elongation ∆l):

where ρ and E are the density and elastic modulus, respectively, of the wire material. The principal components of a vibrating-wire transducer are (1) the mechanical system containing the wire or wires and (2) an auxiliary transducer, usually of an electromagnetic or permanent-magnet type, that converts changes in the vibration frequency of the mechanical system into changes in electric-circuit parameters.

Figure 1. Schematics of vibrating-wire transducers: (a) single-wire, (b) differential; (1)wire, (2) housing, (3) output transducer, (4) diaphragm, (5) spring, (6) output signal, (U) supply voltage for output transducer, (e) electromotive force at transducer output, (p) and (F) measured parameters (pressure and force)

A distinction is made between vibrating-wire transducers with one wire and those with two identical wires (Figure 1). In the second type, which may be called a differential vibrating-wire transducer, the ambient temperature and pressure have much less effect on the results of the conversion of the input parameter. The principal shortcoming of the single-wire transducers is the extreme nonlinearity of the static characteristics. The static characteristics of differential transducers are considerably more linear.

The accuracy of conversion of the input quantity by the transducer is increased when the stiffness of the wire is the principal component in the stiffness of the mechanical system. An example of a vibrating-wire transducer is the differential vibrating-string gravimeter, the relative error of whose output does not exceed ±(10–6–10–8).

A. V. KOCHEROV

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.