Week 6 - Knex Process

After spending another week with Knex to build a bridge, I believe that it is harder than I first assumed. First of all, it was difficult to choose which design or method the team will use to create the bridge because there are numerous different options. In addition, while building the bridge we encountered several problems, such as the parts not fitting with the design due to the limited sizes available. As we moved on fixing the problems, at the end it resulted with a very expensive bridge. The most important observation we saw about the Knex pieces is the 180 groove gussets. The most common procedure is to combine two of the 180 groove gussets to able to create a rectangular prism structure, but it turned out to be very expensive and unstable. Our bridge, which contained numerous 180 groove gussets, was extremely weak and unreliable even though it was expensive. Therefore, it is very important to understand all of the Knex pieces and use them efficiently. In West Point Bridge Design, all the parts played similar role, but the gussets were not as important as they are in Knex. In addition I realized that in WPBD, increasing the cost will increase that strength ratio, which does not occur with knex pieces.

Last week in lab, the groups were allowed to build a bridge based on their design from the A1 assignment using Knex pieces. My group decided to build one bridge as a team effort and incorporate everyone’s ideas. Our bridge was structured in a small rectangular prism with triangles as the web. It contained numerous pairs of 180 grooved gussets, which turned out to be unreliable. This week in lab, each group will test their final outcome of knex bridge and try to analyze how it fails.