Hi! I am Russell, a Sophomore in high school. In this project I used Fusion 360 to make a pedestrian bridge that connects 2 building in my school. The main part of my school consists of 4 buildings in a row with each set of 2 buildings connected by bridges. This leaves just the 2 middle buildings without any connection on the 2nd floor. By creating a bridge between the 2 middle buildings Students will be able to travel from 1 class to another much faster as they could avoid going down and then back up a set of stairs. By creating another possible route for students, the bridge would alleviate some of the foot traffic in my 2,400 student school. The bridge also provides cover from the rain which would complete a full path across the school where rain can be avoided. This bridge would have kept me dry at least 10 times in the last school year.

Pedestrian Bridge.f3d
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Step 1: Measuring the Space

Looking on Google Maps, I measured the distance between the 2 buildings to be about 50'-0". The 2nd floors of each buildings are at different heights. Estimating the height difference the 2 floors looked to be about 6'-0". apart. In Fusion 360, I made a side profile of the desired path on the bridge.

Step 2: Design Ideas

I wanted to design a bridge that is supported by an arch on the bottom, and a simple rectangular box that students would be able to walk through. As it get very hot here in southern CA, I wanted to make the bridge open to the air while also providing cover from the rain. I also wanted a nice array of plants on the sides of the bridge to make up for the lack of nature in that area of the school. To both provide sunlight to the plants, and cover from rain for the students, I decided to add a roll up tarp as the roof which could be opened when in sunlight and covered in rain.

Step 3: Design - Side Profile Sketch

Working off some pictures for inspiration I got onto Fusion 360 and created my bridges side profile. Starting with basic shapes and an arch on the bottom, I created the side profile of my bridge that I would use to extrude most of my bridge. The walkway would be 10'-0" tall which matches with the other roof heights in the school. The bottom sections supports the bridge's loads.

Step 4: Design - Creating the Base

First I extruded the main walkway out 10'-0". This provides enough width for 3-4 people to walk side my side whilst also providing a space for planters along the side. I created a 1'-0" trough to be filled with dirt and used as a planter. I then extruded the bottom support 1'-0" from the side profile. The bottom arch and support would be made of a 1'-0" wide white painted metal beam which can be seen in one of the buildings that would be connected by this bridge. Bringing this material into the bridge gives familiarity to those walking by.

Step 5: Design - Side Walls

I next extruded the upper part of the side profile to create the upper frame of the bridge which would match the bottom of the bridge. To create the wall itself, I created the cross section of the wall and used sweep to create the whole wall. I then mirrored the wall and frame to the other side of the bridge.

Step 6: Design - Roof

The roof is the challenging part of the bridge. I want the roof to act like the roof of a convertible car whilst also being able to collect rain to water the plants in the trenches of the bridge. The roof consists of a full frame around the bridge with high walls to collect water and an area to roll up the tarp which blocks rain. I first created the frame of the roof and then I added the tarp that could be rolled up to allow sunlight to the plants on the bridge or rolled out to create shade or collect rainwater.

Step 7: Design - Details

With the bridge mostly done it was time to add details. I first added a sign on the side of the bridge that faces the outside of the school with the school mascot. I then added similar signs on the other side with the building letters of the buildings that were connected by the bridge. Next was a water tank that was added to hold the rain water that is collected.

Step 8: Scale Model

I decided to use 3d printing to create a 1ft=4mm scale model. At this scale most of the smaller details of the bridge had to be removed. I printed the bridge in 6 main parts with 2 small parts to support the tarp roller cover of the bridge. These parts are then glued together to form the bridge. I then used a piece of paper to represent the tarp on the roof.