about inverted tetrapod

Hallo everyone.
I'm new in this very interesting forum and I'm trying to setup a project.
in linuxcnc have found a possible solution, but i'm not so good in programming to do all alone.
I'm trying to create a model of an inverted four-legs-pod (tetrapod??).
lookin around on the forum and links have found exapods, very interesting tripods and bipods (for vertical printers, for ex.), but couldn't find anything for tetrapods.
I need this configuration because, against the tripod, my field is rectangular, and i've to fill all the possible positions.

Do you know if there's some code already done for this, where i can study, or take as an example?
I think that starting coding from the beginning would be too hard for me..

thanks for any help.

davide.

up?