Is there a way to use an arc length of a revolved edge as a global variable? I have tried adding a global variable in the Equation Editor using the "Measure" option and selecting the end points and the arc as I would to dimension it on a drawing, but all I get is the chord length (i.e. distance between the points) or the radius, depending on what order I select them in. It seems like it only recognizes the first two clicks. I have also tried creating a sensor from the Arc Length displayed in the regular measurement tool, but it seems you can't use a sensor in an equation, which is what I'm ultimately after.

What I'm really trying to do is measure the arc length of a curved part and then use that value to define the length of the flattened configuration in the same part.

Using SW 2016. We don't have the flattening tool... yet...

Can you add a sketch (even convert entities would do) on that edge? If yes then you can create a driven arc length dimension and use that for the equation.