I'm taking this semi-seriously. The biggest intellectual hurdle is figuring out where I would park the thing.
I want to put a hitch on my car and restore the Westy trailer anyway, and it has a steel frame supporting a plywood box. The tongue and axle bolt together and there is a 2x2" wooden joist supporting the back of the box. Deleting the box would make it a dolly. The tongue is 3' and the axle is 53" to the outside of the trailing arms. The wheels are 16x5".
Your wheels are smaller, and you plan on four, right? I was thinking of a towable model but to match your dimensions it would have to be trailerable.
My thought experiment is hang a flag on a long pole off the back of a short trailer. When the tow vehicle turns the trailer will follow, but the flag will be tangent to the curve and outside it. The steps would be:
- Add a trailer hitch (and take the chatter out of the clutch)
- Restore the Westy trailer frame (new elastomeric snubbers and bearings)
- An asymmetrical pyramid made out of angle iron from Hollywood bed frames
- A two frequency geodesic made of luan plywood and aluminum taped edges
- Over that—a removable thin 4v shell
- Bonus: finally a sock over that that could inflate to a compound curve.
If the front wheels were in blisters a 4x10ft model would be half-scale. A Vespa front fork would be a good match for the Westphalia wheel size.