The teams bring the adrenaline rush of an amusement park ride to the backyard of 13-year-old Andreas Hoffman.
- 1) The Challenge (4:06)
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Bonus Footage
Inside the Green Team
Inside the Purple Team
- 1) The Challenge (4:06)
- 2) Brainstorm (5:11)
- 3) Design (3:15)
- 4) Build & Test (5:47)
- 5) Test Day 2 (4:38)
- 6) Judging (4:30)
- 1) Why Deysi Can't Flip (1:04) Deysi has trouble flipping forward because of where the pivots are positioned against her body. Picture a horizontal line running straight through Deysi's body between the two pivots. This is the line, or rotational axis, around which she'll perform her flip. The farther a mass is from the rotational axis, the more effort is needed to flip. So if more of Deysi's body starts out below this axis than above it, she'll find it much harder to flip. But if the pivots are moved lower down on Deysi's body, she should be able to perform the flip almost effortlessly.
- 2) Purple Brainstorm (0:51)
- 3) Green Brainstorm (0:57)
- How do you turn a boring backyard into a fun place to hang out? The teams must design a backyard thrill-ride for twelve-year-old Andreas, using a high-tension cable that can support an aerial ride that spans across the yard. And this time the teams will be the girls vs. the boys!
- The Green Team gets inspiration from Nick, who volunteers to test different ways to attach the ropes to the harness. Then they try out different ways of riding.
- In order for him to fly "superman-style," the Green Team adjusts the ropes over Nick's center of mass so that he is horizontal. They also decide to use a trampoline for rider to rebound off of.
- Instead of using a rope, the Green Team decides to use bungee line. This will make the rider feel kind of like he's weightless. The team also puts in a few more trampolines to help the rider bounce around the yard. They also make the harness more comfortable by adding some padding.
- At the final test, Andreas enjoys bouncing around the yard from trampoline to trampoline. But he points out that if the trampolines were a little bigger, he wouldn't hit the posts as much. In the end, Andreas liked the Green Team's thrill ride the most. The boys are the winners of this challenge.
- How do you turn a boring backyard into a fun place to hang out? The teams must design a backyard thrill-ride for twelve-year-old Andreas, using a high-tension cable that can support an aerial ride that spans across the yard. And this time the teams will be the girls vs. the boys!
- Purple Team is inspired by movie stunts that simulate flying. They decide to use a double harness that will allow the thrill-rider to spin and flip, instead of just moving forward and backward on the high tension cable.
- The Purple Team's design uses a combination of two suspension ropes that connect at a single swivel point above so the rider can spin, and swivels at the hip so the rider can flip. To keep the suspension ropes from getting in the way, the team slides a spreader bar through the ropes to give the rider enough room to flip.
- In testing, the Purple Team discovers that it is hard for Deysi to flip forward. Kim devises a plan to add more rigidity to the harness. They also replace the swivels with ball bearings to increase mobility.
- At the final test, Andreas spins and flips across his yard. He liked the flips, but they also made him motion sick. Although the Purple Team's ride was thrilling, the disorienting nature of the design just wasn't as fun as the Green Team's. The girls lose this time, but challenge the boys to a rematch next time around!
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