Week 6 - Knex Process

After working with Knex for another week, my views of the similarities and differences have not changed significantly. The one difference that I have to address is that WPBD is merely a program that is helpful in terms of planning and preparing, while Knex is a practical situation in which we have to do much calculation and make the bridge as strong as possible while under certain constraints. Another important change is that I have underestimated the difficultness of building a bridge with an acceptable cost and weight ratio using Knex. The original plan was to build the sketch that I have made from the previous week, but as I was building it, I have encountered many problems. The first problem is that I did not calculate the angle correctly, which results in the weak connection on the edges of the bridge. After adding some extra gusset plates and replacing longer chords with shorter chords, the bridge seemed to be stronger. But then, another problem arose—the price of the bridge. The price would be way over our budget, and the only way to actually build a “good” bridge is to redesign the whole bridge.

During last week’s class, each group was asked to build their “best” A1 design using Knex pieces. Originally, my group was thinking about combining all of our ideas and to build a whole different bridge, but we quickly realized that it would take forever to make a new one. Therefore, we each built our own bridge and voted which one was the “best” design. We did end up combining ideas of each other into our group bridge. Next week in class, each group will test their final Knex bridge.