Special-Purpose 2D B-spline Tools
These tools in the Create Curves toolbox are used to place the following special types of 2D B-spline curves.
The Conic Curve tool is used to place a conic section — a hyperbola, parabola, or partial ellipse.
The Spiral Curve tool is used to place a transitional spiral — this is most commonly used for highway design.
The Interpolation by Arcs tool is used to place a complex chain of arcs that passes through a given set of points.