bullet On-line Magazine 'Sensors & Transducers' (S&T e-Digest)

    (ISSN 1726- 5479)

 

Submit an Article

2000-2002 S&T e-Digest Contents


 

Vol. 39, Issue 1, January 2004, pp. 121-127

 

Bullet

 

Development of a Telemetric System Employing a Passive Force Sensor

and a Resonance Frequency Detector with Intelligent Sweeping

 

 

Sergio Francisco PICHORIM, Raul Jose Fernandes de OLIVEIRA

and Paulo Jose ABATTI

 

Paraná Federal Center of Technological Education

Av. Sete de Setembro, 3165, 80230-901, Curitiba, Paraná, Brazil

Phone: +55.41.310-4696, fax: +55.41.310.4683

E-mails: pichorim@cefetpr.br, rfo@cpgei.cefetpr.br & abatti@cpgei.cefetpr.br

 

 

Received:  12 December 2003        /Accepted: 14 January 2004         /Published: 18 January 2004

 

Abstract: This paper describes a telemetric system designed to measure muscular force remotely. The sensor is composed by a simple LC resonant circuit assembled inside a silicone rubber tube (sensor final dimensions are 22.0 x 2.15 mm). Small rings that fix the sensor transmit the force to the silicone rubber modifying the inductance value, due to the displacement of a small ferrite rod close to the inductor. The resonance frequency of the sensor, which depends on the applied force, is monitored remotely (few centimeters apart) using a frequency detector with intelligent sweep (sweeping range can be modified to find out the sensor resonance frequency in few milliseconds), presenting the sensor resonance frequency on-line. In this work muscular force was simulated using standard weights, showing that the system presents errors smaller than 65 mgf, on a 0 to 17 gf range.

 

Keywords: passive sensor, telemetry, resonance frequency, force measurement, remote

 

WinZip Logo Click <here> or title of paper to download the full pages article (114 K).

 

 

 


1999 - 2004 Copyright ©, International Frequency Sensor Association (IFSA). All Rights Reserved.


Home - News  - Archives - Tools - Standardization - Patents - Marketplace  - Projects - Wish List - Subscribe - Search - e-Shop - Membership

 Members Area -Sensors Portal -Training Courses - S&T Digest - For advertisers - Bookstore - Forums and Poll - Sensor Jobs - Site Map