The parametric equations of the evolute of an epitrochoid specified by circle radii 
and 
with offset 
are
 |  | ![(ah(a+b)c_1(t)cost+bc_2(t)cos[((a+b)t)/b])/(b^3+(a+b)h^2-b(a+2b)hcos((at)/b))](/images/equations/EpitrochoidEvolute/Inline6.svg) |
(1)
|
 |  | ![(ah(a+b)c_1(t)sint+bc_2(t)sin[((a+b)t)/b])/(b^3+(a+b)h^2-b(a+2b)hcos((at)/b)),](/images/equations/EpitrochoidEvolute/Inline9.svg) |
(2)
|
where
 |  |  |
(3)
|
 |  |  |
(4)
|
Epitrochoid Evolute
See also
Epitrochoid, EvoluteExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Epitrochoid Evolute." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/EpitrochoidEvolute.html