1. build a bridge that is light but can hold a good load therefore having a good efficiency. made of plastic 1/8in thick.

2. I looked for good designs for structure support and strong bridges, i found that triangles make very strong structures so i made a bunch of triangles in the design for good support.

3. Use many triangles for maximum support and strength, and support all the weak pints with more triangles. made my design in CAD.

4. I ended up using a design with triangles for the best efficiency. using triangles of different shapes and size. being able to support a good amount while weighing a small amount.

5.

6. weight 8.6 held 26.4 wt 11986 eff 1393.67 I got a decent efficiency and was happy with the result, light weight yet supporting.
7. The Problem was not enough support in the center of the bridge. It had to little support all around and collapsed quickly.
8 To redesign this i would add a lot more structure support in the center of the X's in the bridge so it would no longer fail.