A formula useful in the layout of strip transmission lines when two offset parallel traces are to be joined with a smooth S-shaped curve.

In many cases, it is desirable to add a straight section between the two arcs.  The slides below present a spreadsheet for finding angles and lengths as a function of arc radius and trace X-Y separation.

Many years ago, an engineer in a partnering company said he would use an "ogee" in the layout of a microwave strip component.

I had never heard of an ogee.  I asked a coworker if he knew.  He said sure, it was one of the first things he learned in an engineering drafting class.

I think I must have used the above formulas every year after that.