I've posted many finds from the ice fishing community which has produced many simple folding huts that I thought had interesting camping possibilities. In particular, I found the "Ontario style" hut to be particularly simple, light weight, and have a great open/closed height ratio. In addition to the many DIY versions, there is at least one comerical version (with a folding floor). Although used more like a tent, it clearly has camper application but I had trouble finding anyone who tried it. Eventually I found a video of an Ontario folding pickup camper, but the slide show video went 'no longer available' shortly after my post. My attempt to replace that video with a wordy description probably did not gather much attention. Here is a link to my original post of Aug 2020 on pg 9 of this thread
https://www.tnttt.com/viewtopic.php?f=5&t=64495&start=120#p1267550
[youtube]Q2kjtDn1ODw[/youtube]
Well the builder has posted a new slide show video that is far more comprehensive than the original. Note when folded, it adds next to nothing to the height the truck bed, maintaining an unobstructed view out his cab's rear window. Makes carrying along his canoe as simple as with no camper!
Like any covered wagon or tent, I suppose it can be hot in direct sunlight, and I hate the lack of side windows. But I love the very low fold down height, high open ceiling, and zero exposure of the interior to rain while opening.
As I suggested earlier, I think the Ontario design is actually better matched to a trailer than a pick-up: For one, it is easy to extend the door down to the floor level avoiding a 'step-over'entry. For another, the front is more accessible simplifying erection and closing. Judge for yourself.