It arrives in a glossy black box, its sensual shape traced in shadow. My fingers grasp at the perfectly positioned pull-tab and slide the box open. There it sits, the product of the creative minds that helped birth Google’s Project Ara modular smartphone and projects for NASA and DARPA.
It is a straw. Apologies—it is the STRAW, or Suction Tube for Reverse Axial Withdrawal, designed to mix the black-and-tan-esque strata of McDonald's new dual-layer Chocolate Shamrock Shake in perfect proportion.
"My first reaction was, that doesn’t seem too hard. We could have a double straw—one longer, one shorter. No problem," says Seth Newburg, principal engineer and managing partner at NK Labs, which teamed up with JACE Design on the STRAW (the two companies also worked on Project Ara together). "Then we immediately thought, once you get halfway down, one straw is going to start sucking air . . . It’s one of those things that seems so simple, but as we got into it there were a lot more issues exposed. It turned out to present quite a few engineering and scientific challenges."
The STRAW looks something like a saxophone, or a fish hook, with fluted holes. It’s the product of comedic over-engineering, involving white boards, physical prototypes, CAD models, and even fluid dynamics simulations.
"A lot of designs we came up with would work well when the shake was full, or might work when the shake was empty, but in a lot of situations, we found if we didn't get the diameters just right, we’d end up drawing in air, or the first few sips would be good, but you had to wait a minute for the straw to be recharged," Newburg says.
The breakthrough happened in a white boarding session. "One of our team members said, ‘How about we change this? Instead of drinking the bottom up, we drink from the top down.’ They drew a J-shaped straw."
The end of the J would suck in shake, as would two large holes on its tip, allowing you to get the mix you want. But as the shake dipped below the J holes, those openings wouldn’t start sucking in air as a straight straw with holes would. Instead, you could continue sucking because of a vital third hole, on the bottom of the straw. As long as there’s shake coming through the bottom, you close off the pressure system to the tip of the J.
During the prototyping phase the team built many frankenstraws, cutting together their ideas like craft projects and sucking in cups of layered oil and water to test their flow and mixture levels. By spitting out each sip into a side container, they could actually measure how close they were to a 50/50 ratio—a surprisingly low-tech way to check their theories. Meanwhile, they modeled the actual milkshake flow in software, fine-tuning designs with the help of 3D printing.
Then, over the course of 100 or so shakes, bought in bulk from McDonald’s and stored in the lab fridge, the team worked out the finer details of the straw—like how large the holes should be, and what straw diameter worked best as the shake went from thick to more melty.
But did they actually succeed? "At some points when you’re drinking it, you can get an exact 50-50 mix of the flavors. But with the different conditions: Full cup, nearly empty cup, depending how much it melted, you could get some slight variations. But we made sure that you're still getting both flavors all the way through."'
On a particularly warm winter day, McDonald’s PR dropped off a trio of Chocolate Shamrock Shakes for me to test—complete with the final working STRAW.
The STRAW itself is rigid plastic, almost like a metal straw, and it has less girth than your average milkshake tube. But it works. My first sip was something like a frango mint coated in ash from a menthol cigarette (I'm not a mint guy). As I dropped below the radioactive sprinkles, the flavor mellowed out and I quickly found the shake half gone.
However, as I reached the bottom inch or so of shake, I found the sips intermittent, the blasts of air breaking into the stream of dairy fat. I found myself wondering why I couldn’t get that last sip, why the bottom hole that was in place for just this scenario wasn’t coming through for the milkshake portal that is my mouth. Was the STRAW flawed? Was there an error in the physics? Or was there just too much whipped cream in the bottom of the cup for even the most advanced straw on the planet to manage . . .
. . . except for, perhaps, a totally normal one?
Of course, even Apple doesn't always get it right. And the Straw is meant to be, in essence, a very self-aware Christopher Guest documentary in product form. It's meant to poke fun at innovation, all while slyly associating McDonald's with the very idea in the first place.
The STRAW will be distributed for free in McDonald's locations in 80 cities over the next few weeks, with a limited-edition run of 2,000. If it’s a success, it could be mass-produced for a wider market in the future.
[All Photos (unless otherwise noted): via McDonald's]