[Translation of the original French comment]
The Sundog is a rigid wing that was designed by californian Mike Sandlin. Mike has now given up rigid wings and is on to flex wings again.
The Sundog is an evolution of the Skypuppy, another rigid wing of the same type.
here is more information from his website
"Sundog was a rigid wing I built to test the usefulness of flaps on a hang glider (see Hang Gliding, February, 1991). This version has full span flaps which fold under the wing for transport. There are spoilerons on the top surface of the wing for turning, actuated by side motion of the hang loop. The flaps were pulled down by a rope, just like the modern D-cell rigid wings of today. The tail surfaces are just fixed stabilizers. It was too heavy (90lb.s) and the static balance was non-existent (special launch procedures required), but it was fun to fly once you got it in the air. Full span flaps allow simple, easy landings, very similar to a drogue chute."
Also worth mentionning that before that, Mike had designed a Sundog with ailerons:
"These were up-only ailerons, actuated from the hang loop, then returned to neutral by a bungee cord (like the spoilerons, which came later). A good system, but I wanted bigger flaps."