When testing the bridge last week, we had an inexpensive bridge that only held 18 pounds of sand compared to 45+ pounds of other bridges that were more expensive. When we redid our bridge to make it stronger it only held about 10 more pounds and cost about twice as much, so we reverted back to our old bridge. This process - test, rebuild, test, unbuild - took the entire 2 hour class period. Clearly, this is a rather inefficient method of designing a bridge.
When using WPBD it was easy to see the ratios and the cost in an instant when you changed your bridge and you could change your bridge time after time, start new bridges, continue old bridges, and just all around get more data in two hours than by hand with the knex. For this reason, I think it would be nice to have a simple way of calculating cost-load ratios and it would help to know approximately how much stress certain types of triangles can take before something snaps. This would help tremendously when designing the bridge because if certain triangles at certain angles hold more weight effectively, it would be easier to design a bridge using those triangles and then test it and tweak it than just blindly assembling knex pieces and hoping for the best.
This week I hope my group can figure out basic ways to analyze our bridge design and possibly attach some numbers to it so that between this week and next week we can rebuild and/or tweak our bridge design so that it is more effective overall.
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