Austrian artist Klemens Torggler is reimagining the door. His designs are based on rotating squares without the use of tracks. The door displayed in the video above (and images below) is entitled Evolution Door. The two halves of the door are attached by pivots at the bottom and top of the frame and a hinge in the middle.
Torggler has been working on the design for years, experimenting with various materials such as glass, wood and steel. For those worried about losing a finger between the two squares, you’ll be glad to know the door is equipped with soft edges.
Below you will find additional images and videos showing the various designs. I love the ‘clink’ sound the steel door makes!