Final Bridge Plans

Theory: The prototype I have developed a pedestrian bridge that combines a cable stay bridge with a pivot table movement. The pivot table movement will lift a selected section of the bridge up and out of the way for a boat to pass through the bridge. This marriage of form and function has only transformed one side of the bridge. The side of the bridge with the movement attached has been structurally enhanced to support the control mechanism, the movement mechanism and the observation platform.

Movement: The movement mechanism for my bridge prototype involves a cable/pulley system that connects the pivot table section of the bridge to a counterweight which helps to raise and lower the bridge. When the mechanism is activated to raise the bridge the counterweight starts lowering raising the bridge to its final position where it hits a stopping mechanism. When the bridge is activated to lower, the mechanism moves the stopping mechanism forward pushing the bridge back off balance starting it lowering and raising the counterweight. The majority of the work on this prototype movement is done by gravity. Gravity pulls the counterweight down raising the bridge and gravity pulls the bridge down raising the counterweight. The motors controlling the pulleys have to do very little work.

Plan View

Front Elevation (Open)

Side Elevation

Top Right Isometric (Closed)