• Rolling motion on a curve is not complicated as long as curve defined by arcs
    • Find the equidistant curve (dash-dotted)
    • Determine the length of the equidistant path
    • A non-trivial task for paths with Bezier segments
    • Attach a rotational animateTransform element to the rolling element
    • The angle is given by: drot = 180*len/(r*pi) [in degrees]
    • Then attach an <animateMotion> element along the equidistant path. 
      <circle r="r" .. 
 <animateTransform type="rotate" values="0;drot" dur="t" .. /> 
  <animateMotion path="equidistant" dur="t" .. /> 
</circle>

Animated Planetary Drive, linear transmission behaviour

Planet gears' motion defined by two overlaid rotate transforms

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