Week 9

Last week during our lab period we were asked to begin our final bridge design. Throughout the period we brainstormed and tested what worked and what didn't work. We constructed two designs that we had in mind, both of these designs were drastically different than our first design, they both involved using more single connector plates rather that the ones that have to be connected to each other to be functional. We implemented these plates by conecting the membranes differently, the memebers were connected on their side rather than their ends. Unfortunately this didn't work as planned, the bridge failed because it twisted and bent sideways. Although these designs didn't perform as we wanted them to we learned more things about how the Knex pieces can be used. As we come closer to the end of the term I can look back and actualy see how much I have learned about how to design a bridge. Many of the things that I took for granted for example the number of connections that were used in the design have a direct effect on how the bridge can support a certain load. I have also learned that the way the members are positioned also affect the distribution of the stresses of each member. The most crucial thing that I learned was how the bridge bent when it was loaded. This helped us decide on putting an extra truss in the middle of the original truss.