This is something I have looked at on a number of occasions, and I've yet to come up with a satisfactory solution.
We regularly attach components such as paddles to timing belts. The timing belt is punched with a series of pairs of holes. Each pair of holes has a mounting block screwed to it. See the attached picture for a better understanding.
At the moment, I typically create one pair of holes, then use a Curve Driven pattern to create regularly pitched pairs of holes around the belt.
Each attachment is brought into the assembly as a sub-assembly, and mated to the holes using Concentric mates.
Where the holes are on a flat portion of belt, I then use a co-incident mate between the underside of the attachment and the belt surface.
If the holes are on a radius, I use a tangent mate instead.
This is kind of functional, but I want to be able to move the holes to any position within their cycle. Say I have a 70mm hole pitch, I want to be able to move +/- 35mm from the datum position.
The issue I have is that as soon as a hole that was on the flat moves onto a radius, the coincident mate fails. And vice versa.
If the holes are half on the flat, and half on the radius, that's even more of a pain.
Any suggestions on the best way to achieve this in a robust manner would be appreciated.