The kyoto trough uses troughs with their curvature at right angles to each other to mimic a parabolic dish. Bending and cutting sheet material to make the trough requires as little as 2 cuts of the sheet material.. On the other hand
Cutting sheet material to make a parabolic dish is a massive undertaking!
I have made a first prototype and it works.
It is"tweaked" to provide 2 hours of cooking time at pretty much full power. So you can set it and leave it. A parabolic dish on the other hand needs to be adjusted every half hour.
The trough arises from a solar software project I did.
I have uploaded the most recent scene file here thirdcombined troughblabla.aoi If you download it, it might change the file extension to .temp. Just change it back to .aoi and it will work just fine when you open it in art of illusion
The file just happens to contain a parabolic dish, winston curve dish, and various others too. And all in 11kbytes!
Art of illusion software certainly helped me come up with this design.http://www.youtube.com/watch?v=qXVfGFQpYD8
shows my first prototype Kyoto trough.