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sensors:linear_variable_differential_transformer [2021/03/22 21:35] – [Signal Conditioning] greg.sikorasensors:linear_variable_differential_transformer [2021/03/24 21:03] (current) – [External links & references] greg.sikora
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 {{ :sensors:vemuri.png?nolink&600 |}} {{ :sensors:vemuri.png?nolink&600 |}}
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-Below, a __simplified__ mathematical model of the LVDT demodulation (hover over the image for caption): +Below, a __simplified__ mathematical simulation of the LVDT (MaxMSP) demodulation: 
-{{ :sensors:matlab1.png?nolink&400 |Simulation of the core displacement (3 sec., 0.5 - null position, the blue line represents core displacement)}} +{{ youtube>4fGsUOM2kjI?large }}
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-{{ :sensors:matlab2.png?nolink&400 |Secondary coils excited with a sinusoidal signal (Fe = 10 Hz, for the purpose of visualization)}} +
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-{{ :undefined:matlab3.jpg?nolink&400 |Full-wave rectification of the signals at secondary coils}} +
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-{{ :sensors:matlab4.png?nolink&400 |Low-pass filtering}} +
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-{{ :sensors:matlab5.png?nolink&400 |Fully demodulated signal (difference over sum)}} +
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-A similar mathematical simulation (MaxMSP) of the LVDT with demodulation: +
-{{ youtube>AudtIkBpXbo?large }} +
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   * (Hoadley1936) George B Hoadley, “Telemetric System”. US Patent Application #2196809, March 17th 1936 (Patented on April 9th 1940).   * (Hoadley1936) George B Hoadley, “Telemetric System”. US Patent Application #2196809, March 17th 1936 (Patented on April 9th 1940).
   * (Powell2009) Mike Powell, //[[http://www.mikesflightdeck.com/lvdt_circuitry.htm|Mike’s Flight Deck]]//   * (Powell2009) Mike Powell, //[[http://www.mikesflightdeck.com/lvdt_circuitry.htm|Mike’s Flight Deck]]//
 +  * [[http://nliebeaux.free.fr/ressources/signal.pdf|(Szczyrbak1997)]] Szczyrbak, J. "LVDT Signal Conditioning Techniques", 1997
 +  * [[https://www.ti.com/lit/an/slyt704/slyt704.pdf?ts=1616609560481&ref_url=https%253A%252F%252Fwww.google.com%252F|(Vemuri2017)]] Vemuri, A. & Torres, H. "Signal-to-noise ratio of an LVDT amplitude demodulator", Analog Applications Journal, 2017
 +  * [[https://dl.acm.org/doi/10.1145/3057039.3057103|(Petchmaneelumka2017)]] Petchmaneelumka, W., Songsuwankit, K. & Riewruja, V. "Simple LVDT Signal to DC Converter", 2017
   * eFunda, 2005, //[[http://www.efunda.com/designstandards/sensors/lvdt/lvdt_theory.cfm|Theory of linear variable differential transformer (LVDT).]]//     * eFunda, 2005, //[[http://www.efunda.com/designstandards/sensors/lvdt/lvdt_theory.cfm|Theory of linear variable differential transformer (LVDT).]]//  
   * RDP Group, 2002, //[[http://www.rdpe.com/displacement/lvdt/lvdt-principles.htm|LVDT principle of operation.]]//   * RDP Group, 2002, //[[http://www.rdpe.com/displacement/lvdt/lvdt-principles.htm|LVDT principle of operation.]]//