Invoblspheroidal:

x = a*cosh(u)*sin(v)*cos(w)/(cosh(u)^2-cos(v)^2)

у = a*cosh(u)*sin(v)*sin(w)/(cosh(u)^2-cos(v)^2)

z = a*sinh(u)*cos(v)/(cosh(u)^2-cos(v)^2)