Identify Problem

Design a full scale flat-pack chair to be cut out of plywood and put together, to be tested over a long period of time by many different sizes of people

Constraints:

• Must fit within a 4x8 sheet of plywood

I based my design off of a standard Adirondack chair because they're the universal standard for a comfortable chair. I found a photo of a basic looking Adirondack chair that showed all of the dimensions for the chair, but I tweaked it because I wanted it to be slightly less of a lounge chair, so I'd be able to do work while stting in the chair (as I attempted to illustrate in the sketch)

Test & Evaluate

In the testing portion, I put the bridge on a machine that applied a great amount of force to the center of the bridge deck, the weakest part of the bridge deck. I measured the dead load (the weight of the bridge), the live load (the total weight held), and the efficiency (live load/dead load). The efficiency is the most important part, as opposed to the live load, as it's the best indicator of how well the bridge performs based on the weight.

If I were to redo this project, I would simplify the top to reduce weight and use the unused wood strips to connect the truss to the deck with wood glue instead of hot glue. The full length strip not only makes it easier to glue, but also adds more surface area of wood glued to the deck, meaning it would be a lot less prone to disconnecting.

This project taught me a lot about not only the forces and physics of a bridge, but that I tend to spend a lot of time on the smaller details, such as how the glued joints look, instead of getting the project done first. In future projects, I will work on getting the project to a functional stage before hyperfixating on the minute features.