Violet rollers bear the weight of blue door.
Green rollers are for guiding.
The door is connected to the upper sliders via revolute joints.
The 45 deg. corners at the rail ends make the door flush with the wall.
Blue lower rail fixed to the door and violet pin fixed to the ground and moving in the slot of the lower rail keeps the door from swinging.
This video was made on request of a YouTube viewer.

STEP files of this video:
http://www.mediafire.com/file/lftpbn7...
Inventor files of this video:
http://www.mediafire.com/download/6y5...
Related sources:
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