Technology

Fuck Wired and their shitty paywall. Here for anyone interested:

Pole vaulting is one of the more outlandish Olympic events. The primary instruments of the sport are curious creations—big sticks, between 10 and 17 feet in length, that certain track & field Olympians hold while sprinting, then jab into the ground and hang on to as they hurl themselves through the air to achieve increasingly greater heights.

If that sounds dangerous, well, that’s because it is. There have been dozens of injuries in pole vaulting, even at the Olympic level. Most of them occur when a vaulter hits the landing pad wrong, or misses it entirely. But there are also often problems with the pole. After all, flinging a human body up to 20 feet in the air takes a lot of kinetic energy, and puts a lot of pressure on the pole.

If something goes wrong—even a small, invisible fracture in the pole—that instrument can snap into pieces and send the unfortunate vaulter tumbling to the ground. Pole breaks have had disastrous consequences, causing athletes to suffer injuries as severe as brain hemorrhaging.

Clearly that’s not ideal. But someday, it might be possible to head off some of those failings by making poles that can fix themselves before they break.

Vaulting poles have a storied history that have led to the creation of the sport. Ever since human beings figured out how to break large sticks off of trees, they have been using them to launch themselves over and around things. At first, vaulting poles were used to close distances, like hopping over gaps or getting across particularly soupy patches of marshland.

The ancient Greeks used them in their athletic competitions, though the goal was to cover the most distance across the ground. The idea of turning vaulting into a sport where people aimed to achieve the most height was started by a cricket club in Ulverston, England, in 1843. Pole vaulting first came to the Olympics in 1896, and has been propelled back into the limelight every four years since. Old Poles

The earliest poles were made from wood, like ash or bamboo. As you might imagine, they broke often. But poles have matured, advancing through the years to incorporate stronger materials such as aluminum and steel. In the 1960s, reinforced fiberglass became the go-to lightweight material.

Modern poles are typically formed with layers of fiberglass and carbon-fiber composites. Curiously, there are currently no regulations that mandate what materials are used to make the poles themselves. Yes, they break far less often than the bamboo shoots of old, but still aren’t perfect.

Vaulting poles, as you probably know, bend quite a lot when projecting a person up into the air. (UST Essx, a company that makes vault poles, tests its products by bending them down to 65 percent of their standing height—forming a near C shape.) That means poles have to be made with the right combination of materials to be both sufficiently bendable and sturdy to keep from splitting apart. They’ve got to be strong enough to hold a person’s weight, and light enough to be held while running.

Properly taken care of, modern poles can last for years or even decades. But over time, or after being mishandled or stepped on, little cracks and divots can occur. Sometimes, they’re so small they can’t even be seen, but still compromise the pole’s structural integrity all the same.

Pole vault breaks come without warning—and can be catastrophic.

“Cracking and voids are the enemy of the composite,” says Don Rahrig, VP of engineering and product development at Essx. He says these sometimes-invisible imperfections can spell doom for the pole. “What will happen is your cracks will propagate—a little bit like cracking in your windshield. And then when it fails, it's catastrophic.”

Even in the advanced age of complex fiber composites, poles aren't invincible. They can break for a few reasons. It can happen if a vaulter uses a pole that can’t handle their weight, or if a crack or defect leads to structural failure. Trouble is, when there’s a problem, poles tend to break in an instant. They can snap and shatter under the pressure of a jump—sometimes with injurious consequences for the recently airborne vaulter.

As for the pole itself, there isn’t much you can do with the bits after a catastrophic break, as the structural fibers cannot be completely sewn back together once split. Little of the pole can be salvaged or recycled afterwards. The rest of it goes in the trash. New Thinking

There are a few potential ways to try to stave off these problems. A paper published by Georgia Gwinnett College suggests the idea of adding an gloss across the surface that can release dyed microcapsules when cracked, making splits more visible when they occur. If athletes could spot those cracks early, they could avoid an equipment failure before it occurs. That’s helpful, but what would be ideal is a way to not just find the cracks, but to fix them.

Rahrig says materials scientists at Essx and elsewhere are steadily working to make poles more repairable and potentially reusable. Part of that effort—not now, but someday—might be making vault poles that can all but heal themselves.

The Swiss company CompPair focuses on composites with the goal of making products more repairable. Its hallmark composites rely on what CompPair calls HealTech technology to create a healable surface. The way it works is that when something gets scratched or dinged, heating up the resins that hold fibers together could soften them and let them slowly seep back into shape.

The process isn't instant. Depending on the break it can take minutes, or sometimes a day or more. But once it's done, the compound should be reset to almost as good as new. To be clear, this process has never been used in a vaulting pole. CompPair has tested its composites on mostly flat surfaces that are easier to control for. Getting those composites into a vault pole—while maintaining the integrity of the structural fibers—is a whole other challenge.

CompPair cofounder and CTO Robin Trigueira says there is a world in which utilizing these kinds of composites could help usher in more repairable sporting equipment. Trigueira says he can envision a possible future where Olympic stadiums provide very long ovens that vaulters can place their healable poles in overnight to ensure they're nice and sealed before event time.

“I think it's possible.” Trigueira says. “But we must test it thoroughly to learn something like this.” Self-Healing Future

The trouble with using these composites inside something like a pole vault is that it is exceedingly complicated to make sure it solves the problem at hand. Adding a new composite because it is healable could also add a whole variety of new variables that could not mix well with the structural components of the pole. Adding a gloss on the surface to make cracks visible could change how the vaulter grips the pole.

Every crack and divot is different, and may not heal the same depending on how it develops. There might be some damage that is too structural to melt away with a little bit of composite redistribution. Depending on the defect itself, it may take a long time to fix. Also, heating the healable resins might mess up the other composites.

Trigueira compares the process to an injury on the body. If you’ve just got a scratch on your arm, you might not even bother to do anything about it, and it will heal quickly. But something deeper and more serious will take more time to figure out, and may lead to additional complications.

“It’s very rare that you suffer the exact same injury as somebody else,” Trigueira says. “Is the part taking little scratches, or more deep wounds? This we need to know in order to be efficient in the healing.”

The idea of using healable composites in poles is also not a new one. It has been around since at least 2017, but no healable poles have been created—yet. Rahrig says Essx isn’t currently working on any efforts to add such a healing resin or composite to its poles, though doesn’t discount that some day it might be utilized to make a longer lasting pole.

“We’re investigating materials like this all the time,” Rahrig says. “That’s purely research level right now. It’s very interesting, but how it would be used in a pole, I’m not so sure.”

Outside of Olympic competitions, pole vaulting has a smaller presence in the sporting world more broadly. There isn't much money in pole vaulting, so it's likely these kinds of materials will appear elsewhere first. Trigueira says CompPair is not currently working with any pole vault companies to put its composites in their products, but says it is working to implement them in more prominent sports equipment such as surfboards and bicycle frames.

So while it may be some time before this sort of innovation graces the humble vaulting pole, both Rahrig and Trigueira say it’s both possible and likely. “In 10 years, I think, it’s a safe thing to say there would be a pole vault with healable composites,” Trigueira says.

Correction: 07/26/24, 8:51 am: Clarified that CompPair is working on healable composites for bike frames, not bike pedals.