16-12-2009, 05:48 PM
A transducer is a device which transforms one type of energy into another, devices which translate an input of mechanical energy into equivalent electrical signals for
measuring and/or controlling the input phenomena. The resistance strain gage, because of its unique operational characteristics, has dominated the transducer field for the past twenty years or so.
Transducers can be, and are, based on many different operating principles - resistive, inductive, capacitive, piezoelectric, etc. specialized developments in bonded resistance strain gages are:
Semiconductor Gages
produced in the form of gage patterns deposited on suitable insulating substrates,
Deposited Metallic Gages
metallic films are deposited on pre-insulated transducer structures and used as bonded resistance strain gages.
The Bonded Strain Gage as a Transducer Element
Advantages:
-Small size and very low mass:
-Fully bonded to basic spring structure:
-Excellent linearity over wide range of strains
-Low and predictable thermal effects
-Highly stable with time
-Relatively low in cost
-Circuit output is a resistance change
Disadvantages;
-Thermal degradation
Output signals are relatively low
Moisture effects
Careful installation procedures required
Detailed seminar report download:
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