How to draw a catenary curve in AutoCAD/GStarCAD/ZwCAD

Drawing the curve of a hanging chain or cable in your CAD program

In physics and geometry, a catenary is the curve that a hanging chain or cable assumes under its own weight, when supported only at its ends.

The catenary curve has a U-like shape, superficially similar in appearance to a parabolic arch, but it is not a parabola.

Mathematically, the catenary curve is the graph of the hyperbolic cosine function. The formula is as follows:

    y = f = c1/2 * (exp(x/c1) + exp((-1)*x/c1))

where c1 is the catenary parameter.

    ZwCAD users need to check LitioLAB user manual to review the math functions available and how to adapt the formulas to ZwCAD.

    The EXP() function is not available in ZwCAD. Use e^() instead.

Pick the ends of the cable, and the cable length

With LitioLAB, just pick two points (the ends supporting the catenary), and enter the catenary length, to get shape the cable or chain will assume, for example, to check the free space below a cable.

Check the following video:

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