Follow can be used to check the fastest line through roundabouts. Define the path through the roundabout as a AutoCAD spline, pline, Civil3D alignment or MicroStation complex chain. Set the design speed to the highest permitted and use Follow to generate a non-editable path. Autodesk Vehicle Tracking will reduce the speed to the maximum possible. The current version does not take into account acceleration and deceleration, but it does allow for dynamic effects.