This document discusses various types of transducers. It begins by defining transducers as devices that convert one form of energy into another. Sensors and actuators are described as input and output transducers, and can be either analog or digital. The document then discusses factors like ruggedness, linearity, and dynamic response that are important in transducer selection and design. Examples of specific transducer types discussed include bourdon tubes, bellows, strain gauges, thermistors, and digital encoding transducers.
4. TRANSDUCER
• Transducers convert one form of energy into
another
• Sensors/Actuators are input/output transducers
• Sensors can be passive (e.g. change in
resistance) or active (output is a voltage or
current level)
• Sensors can be analog (e.g. thermocouples) or
digital (e.g. digital tachometer)
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5. Necessity of Transducer
Ruggedness
Linearity
Repeatability
High Stability and Reliability
Good Dynamic Response
Convenient Instrumentation
Residual Deformation
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6. Selection of Transducer
• Physical quantity to be measured
• Transducer principle –suitable for the quantity
to be measured
• Accuracy in the measurement
• I/O characteristics transducer with the recording
system
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7. Advantages of Transducer
• Amplification and Suppression can be done
easily.
• Mass-inertia effects are minimum
• No friction effects present during –indication
quantity.
• Measuring systems controlled with least power.
• Output can be easily received, transmitted &
processed before measuring.
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15. Bourdon Tube
• Bourdon tubes are known for its very high
range of differential Pressure Measurement in
the range of almost 100,000 psi (700 Mpa).
• It is an elastic type Pressure transducer.
• Eugene Bourdon in the year of 1849.
• Various forms
C type
Spiral
Twisted Tube
Helical
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19. Bellows
• Bellows is used for pressure measurement, can
be made up of cascaded capsules.
• Expanded or contracted axial by changes in
pressure.
• Materials Commonly used :
Brass
Bronze
Beryllium copper
Alloys of nickel & copper
Steel
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29. Digital Encoding Transducer
• A digital optical encoder is a device that
converts motion into a sequence of digital
pulses.
• By counting a single bit or by decoding a set of
bits, the pulses can be converted to relative or
absolute position measurements.
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