JH Seniors Make Design Decisions

Since deciding on the exact location of the bridge at the February 17th meeting, many design decisions have been made by the John Hay Seniors.  Cost of materials, schedule, bridge purpose/users, site restrictions and bridge design coolness all played a part in the group's final decision.

Dom demonstrates how the draw bridge
on the High/Low Bridge would move.

The group learned about 12 different movable bridge options, from a draw bridge to submersible bridge to swing bridge to retracting bridge and everything in between.  Four groups of students were formed to discuss the pros and cons and determine their favorite style.  Remarkably, each group had a different favorite: one side swing, two side swing, high-low bridge and tilting bridge.

Devo, Angel and Chereese build
the two sided swing bridge

At our next meeting, we stayed in those same student groups and supplied them with lego building blocks and other materials (cardboard, pipe cleaners, aluminum foil, tape) and had them build their chosen bridge.  The catch was that they had a $3500 budget and each building material had its own cost.  They needed to estimate how much materials they needed on the initial purchase and hope they "guessed" right because the price of everything went up on future purchases.  The group also had to develop a bar chart schedule of how long it would take to build their bridge (again each building material had their own construction duration).  The mentors and students voted on bridge style for their final project (and they were not allowed to vote for their own bridge).  The two sided swing bridge won (by 2 votes).

The one sided swing bridge that lights up
as you step on it.  Think Michael
Jackson's Billie Jean video.



At the March 17th meeting, we discussed that just like the various bridge structures, there are many types within a structure.  Within the two sided swing bridge structure, we discussed four styles: cable stayed, box/truss, slinky or inclined ramp.  Each group was given foam core boards, wood, glue, rubber bands, etc. to build one of those styles.  The task was meticulous but it quickly came apparent that no one wanted to select their own style as the bridge style for the final project....except for one group.  Everyone was in favor of the slinky bridge style.  See, design coolness definitely ruled that decision.



It's a Slinky style two sided swing bridge!