Hudson - A3

Image 1: First page of Method of Joints calculations

Image 2: Second page of Method of Joints calculations

Image 3: Truss Diagram with Forces

Image 4: Table of Tensions with Member to Member Labels 

Image 5: Bridge Designer of Fictitious Truss 

4) Because the Bridge Designer application can't be made to scale, the weights are going to be different than in my analysis. In my analysis I was able to use the exact distances whereas in the Bridge Designer application the distances had to be scaled down to fit in the grid.

Image 6: Bridge Designer of Knex Truss

5.2) The largest force in the Knex truss when you scale off of the Bridge Designer numbers would be approximately 60 which would be found in the middle of the bridge when using 20 pounds of weight. This falls into the expected range of 0-100 before the bridge would break. The forces get larger the closer they get towards the middle of the bridge on the outer edges, but the inner cross-sections have the same tension through-out. While this is possible, it's not entirely plausible which could be the result of the way Knex hold weight.

6) This type of analysis is useful because it allows us to quickly see how what the compression and tension forces are in our bridge so we can modify our bridge accordingly. When you couple this with the information about how knex hold up under different forces you can predict how the knex are going to behave under certain weights and modify the bridge structure to work around these failings.