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CAD tip # 9699:
Question
A
You can draw a clothoide (Euler spiral, Cornu spiral, Track transition curve) - a smooth transition between an arc and a straight segment using the LISP utility KLOT, see
Download. Load it with APPLOAD, start the KLOT command and pick the endpoints of an arc and a line. The application will draw the clothoid-transition (red in the picture):
Download. Load it with APPLOAD, start the KLOT command and pick the endpoints of an arc and a line. The application will draw the clothoid-transition (red in the picture):

Since release 2024, you can use LISP apps like this also in AutoCAD LT.
Other transition curves can be generated using the road/railway design functions in Autodesk Civil 3D.
ACADADTACLT
16.2.2014
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