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Why does DataStudio compute velocity from x(t) the way it does?

  1. Jan 25, 2013 #1
    A motion sensor gives the position of an object at times separated by Δt. DataStudio then calculates velocity by this method:

    v(t) = (x(t + 3Δt/2) - x(t - 3Δt/2)) / 3Δt

    I wonder why it doesn't do it like this: v(t) = (x(t + Δt/2) - x(t - Δt/2)) / Δt

    I know it gives the same v if acceleration is constant since in both cases it corresponds to average speed in the middle of the interval, but if acceleration is not constant (e.g. mass-spring) it must give a value for v that is not as accurate.

    Thank you.
     
  2. jcsd
  3. Jan 25, 2013 #2

    cepheid

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    Maybe the velocity is averaged over multiple timesteps as a smoothing (filtering) feature. An average velocity computed using every single sample might have too much high frequency jitter due to noise.
     
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