Cassini Wheel (N=4 4R Virtual Wheel)
Virtual radius wheel (r = 4R ). Square wheel. related Chebyshev Linkage (quasi-straight line).
Detailed explanation is described in "Cassini Wheel" .
If this wheel edge were bigger than stair step, it's easy to climbing stairs (?).
■ about Planet orbit
In this figure, If A were the earth, C were the moon, C rounds by θ speed, and C self-spins [= CC' round] by average θ/2 speed. i.e. θ : θ/2.
Reuleaux triangle approximation system is θ : θ/3 speed. [in this case, θ/3 is not average speed, is exact speed.]
Tip: Reuleaux triangle Wheel was 2R virtual radius system, but this Cassini is 4R virtual radius system.
Reuleaux body was rigid, but this Cassini is amorphous body.
■ Is this a constant velocity?
Please tell me.
■ 360゜: circle → 2π r ≒ 6r, square → 8r; So, 4/3=1.33 times longer edge length.
■ Hybrid Reuleaux triangle ---- added on 2016/12/09
4 corners should be replaced by Reuleaux triangle corners. Corner's curve becomes more flat (i.e. 2R curve).
i.e. blue is 4R arc, purple is 2R arc.