Options for Measuring Displacement and Motion
PrintResistive (potentiometric)
- Current excitation
- Linear
Resistive Option
LVDT (linear variable differential transformer)
- Core movement through transformer
- AC excitation
- Phase voltage output change
Encoders
- Pulsed output
- Quadrature
Encoder Option
You can measure linear displacement by using a potentiometric sensor or an LVDT (linear variable differential transformer). You can measure angular displacement or rotation using an RVDT (rotary variable differential transformer) or an encoder.
Potentiometric sensors are resistive and can be read by applying a current and measuring the voltage drop across the resistor.
An LVDT is more complicated and requires AC excitation. The output is AC and can be measured by changes in peak-to-peak voltage and phase shift.
Encoders typically generate a TTL-level pulse train.
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