Mark Rober’s 5 Toughest Feats of Engineering

YouTube engineer/prankster Mark B. Rober (BS ’04) only makes it look easy. Here’s a countdown of the five feats that gave him the biggest fits.

YouTube engineer/prankster Mark B. Rober (BS ’04) only makes it look easy. Here’s a countdown of the five feats that gave him the biggest fits.

5. World-Record Elephant Toothpaste Explosion

After setting, and then losing, the record for the world’s largest “elephant toothpaste” experiment, Rober says he wanted to take back what was “rightfully mine.” But as he went big, the scaling got tricky. Rober conducted hundreds of tests of the expanding foam with custom-built flasks to figure out how to maximize volume and height, eventually landing on a 20-foot behemoth. “You only get one shot at the 20-foot test,” says Rober. He got the record, but he notes that “there was so much pressure [from the reaction], the thing lifted off the ground. Stay tuned for version 3.0 to learn from those mistakes though.”

4. The Automatic Bull’s-Eye Dartboard

A trick that happens in less than half a second took three and a half years to perfect. Rigging infrared cameras, a motion-capture system, and stepper motors to a dartboard, Rober became a dart thrower who just can’t miss. The biggest challenge? “The entire event takes 400 milliseconds, so the engineering has to happen real fast.”

3. Glitter Bombs

Rober’s signature glitter bombs—his special gift for porch pirates—feature four phones, which film the package thieves and ensure, through GPS, that Rober can retrieve his handiwork. “What makes these so tricky is that they have to work in the wild under a wide range of conditions,” says Rober, such as staying charged while waiting to be picked up, even in cold weather, withstanding drops, and being “opened in super weird ways.”

2. Jell-O Pool

“I lost 8 pounds the week I was trying to pull this off,” says Rober. He opted to create this Jell-O pool in his older brother Brian’s Mapleton, Utah, backyard. “Chemistry isn’t my strongest subject,” says Rober, “and scaling the simple refrigerator Jell-O up to 15 tons of Jell-O presented some challenges—especially with trying to get it to firm up.”

1. Domino Robot

This piece of engineering took the longest—four years from initial design to completion. “There are toys that can set up 20 dominos in a row, but the challenge here is, ‘How do you scale that up to 100,000 dominos?’” says Rober. “And that is a non-trivial problem to solve.”

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