You may be able to achieve what you desire with a composite curve and a curve driven pattern. You may have to create some geometry specifically for the pattern.
If the equality does not need to be precise, a simpler version of CorBlimeyLimey’s suggestion would be to use line segments constrained to be on the curves and have equal length, (think approximating a circle with a polygon). The make path sketch tool may help by allowing the line end points to cross between the arcs.