Bus Door 23 July 2017, 22:00 Sorry, your browser doesn't support embedded videos, but don't worry, you can download it and watch it with your favorite video player! Pink crank, red slider and blue bus door (in role of a conrod) creates a slider-crank mechanism. Violet cylinder controls door opening. Door motion occupies very small room for both inside and outside space of the bus. « previous mechanism Mechanical Counter next mechanism » Making Helix Groove of Variable Lead load comments Please enable JavaScript to view the comments.