Using my space truss module, creates a "platform" with user configurable length, width, and height. Automatically generates the (possibly hundreds of) cylindrical members and does all the trigonometry for you!

EDIT: Using changes to my space_truss() module suggested by qharley, the SpaceTrussBridge files have more diagonal members crossing in both directions.

I also removed a bunch of translate()'s from the sub-modules in the hopes of speeding up the program. Some are still necessary to move parts to the origin to rotate them because Openscad seem's to have ignore the v=[...] parameter in rotate( a=[...], v=[...] ), which would allow rotating around a specified origin instead of the default.

In the Openscad file: Only for the patient! Openscad takes a looooong time to render this. If you aren't patient, go do something that takes less time, like bake a cake under the hood of your car. If you have any ideas of how to make this easier for Openscad to process, I'm all ears! But just call truss_platform() with the length (x axis), width (y axis), height (z axis), and diameter of the cylindrical members. It seems to be faster to export it to STL and view that file with something else.