A3-Reiff

1 & 2.

The professor posted this morning that all of the units should not be in the metric unit.  Currently all of my forces are measured in lbs m/s^2 as I incorrectly converted my forces from pounds to newtons above.  In order to have all of my forces in the correct units of pounds I must divide the force of each member by 9.8.  This will give me the correct force on each member in pounds.

3.

4. The results from the Truss Designer Program and the hand analysis are close to each other.  The major problem between the two is the scaling.  I was only able to use increments of 5N when defining the forces, so some of the forces were not exact in the Truss Designer program.  I converted the 20 pounds of weight to newtons so it could be used with proper units in the Truss Designer program.  However, the biggest problem was that the numbers were not scaled correctly between the Truss Designer program and the hand analysis.  This was most likely the biggest problem encountered.

5 & 6.

The biggest difference will probably be the weight of the bridge made out of knex compared to this bridge, although this bridge is roughly the same design as our knex bridge.  Last time we tested our bridge the truss that failed was in the middle of the bridge.  This can be seen by looking at the analysis above.  The middle is clearly under the most stress.   While support could be added, that could end up adding more weight to the entire bridge, changing the calculations that were just preformed in this analysis.  The best part about this analysis is that I can see where the bridge is most likely to fail, and I can figure out a way to solve this problem with my fellow group members.