Week 5

In the past week, we began experimenting with converting our bridge designs into Knex models.  We familiarized ourselves with the available Knex pieces and joints.  There are limited sizes of Knex pieces and they can only be joined in increments of 45 degrees.  As a result of the limited sizes and joints the designs had to be altered in order to use the right sizes and angles.  I drew my altered design in AutoCAD using the sizes and angles that will be used when building the physical model out of Knex.  In the coming week, our goal is to build our individual bridge designs out of Knex and prepare to test them.  The major accomplishments that we had this week consisted of altering our designs to be compatible with Knex and drawing our designs using computerized methods or hand drawings to get experience.  An issue that occurred this week was designing a bridge using only 45 degree angles.  Our team kept coming up with very similar, almost identical designs during lab.  We found that the designs are very limited when only 45 degree angles can be used.  It was also an issue that the members are predetermined lengths.  In some designs that I came up with, there was not a member available to fit the length I needed causing me to redesign.  

Designing bridges in West Point Bridge Designer is very different from designing bridge models out of Knex.  When using WPBD, there is a lot of variety in the angles, sizes, and thicknesses that are available.  When using Knex, the sizes are very limited and the only angles that can be used are in increments of 45 degrees.  Knex do not allow you to use custom sizes or thicknesses, they are all predetermined.  The design shapes are similar in that triangles are the most common used shape.