The model is one of perhaps six to eight action models I created around 1974-80, all discovered by a habit I had back then of pulling and pushing the paper this way and that after every improvised fold, to see if anything would move. Of course, almost always nothing would happen, but occasionally, something unexpected would happen, and the paper would flip, rotate or expand – and I would have the beginnings of a potential action model.

Click on photo for diagrams.

Paul Jackson