A mirror shaped like a parabola can be used to concentrate energy from the sun on a small area, from which the resulting heat might be carried off by water or some other medium. The following describes a script that creates a custom support structure for such a parabolic mirror. It is referred to as a rib and on one side follows the curve of a parabola, while on the other it is supported by a truss that keeps the parabola in the correct shape. The script is written in Python and runs in FreeCAD, which is an open-source CAD/CAM package. It can be cloned from Github and needs to be placed in the Macro directory of your FreeCAD installation. To find where that is, start FreeCAD and click Edit | Preferences | General | Macro to have a look at the Macro path setting. The following uses the default location when FreeCAD was installed under Ubuntu.

cd ~/.FreeCAD/Macro
git clone https://github.com/inatic/freecad-solar-concentrator solar

 The script is executed in FreeCAD by simple importing it from the Python Console, activating the latter can be done under View | Panels | Python Console. When all goes well this creates a document with a parabola shaped rib as well as a cutlist for the bars that are used to build it. Parameters in the script allow changing the shape and size of the parabola as well as the design of the truss. Once imported and after making modifications to the script, it can be reloaded using the importlib.reload method.

from solar import concentrator
import importlib
importlib.reload(concentrator) 

Details on how the script works can be found on its GitHub page.