Two circles track
Given two radii and distance between circles centers (R, r, d), case: R > r
θ + α = 2π
If r > R then θ is less then 180 ̊
and γ is negative
θ = 2π − α
When R = r then L reduces to:
L = 2d + 2πR
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Note: we used in all the equations the relation R > r
Angle γ is: |
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(R > r) |
Angles between the line connecting the two tangent points of radii R and r are θ and α and the axis:
Arc lengths between the two tangent points of radii R and r are:
And the total track length L is:
L = 2h + Rθ + rα = 2h + Rθ + r(2π − θ)
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