Epicycloid is a parametric curve that is obtained by rolling a smaller circle (r) around a larger one (R). It shows the trace of a point P, fixed on the circumference of the smaller circle.
x(θ) = (k + 1)·cos(θ) – cos((k + 1)·θ)
y(θ) = (k + 1)·sin(θ) – sin((k + 1)·θ)
Larger radius: R =
Smaller radius: r =
Ratio: k = R/r
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