Rocket launches—or earthquakes—are already punishing experiences. But it turns out there are some things that can make them worse: like if the vibrations hit the structure you’re in at just the right frequency to cause resonance, where the vibrations become self-reinforcing and get bigger and bigger, in some cases up from bearable to all-out disastrous.
But what if you could turn off that resonance with the flip of a switch?
NASA took on the problem when engineers at Marshall Space Flight Center discovered in testing that the Ares I launch vehicle displayed a serious vibration problem that could be potentially hazardous to the crew sitting right above the booster.
Their solution, appropriating the mass of the hydrogen fuel in the second-stage rocket to dampen the vibrations, worked better than they had even imagined. In testing, “they were getting a knock-down on vibrations that was 50 to 100 times more than could be explained,” recalls project manager Rob Berry.
Team members began to realize they hadn’t designed a variation of standard dampers—they’d come up with something fundamentally new.
When they put their new device in the fuel tank, they expected to dissipate the force of the vibrations into the liquid. But instead, they realized they were actually causing the fluid to act as if it was no longer part of the spacecraft structure, which meant the resonance no longer occurred.
The result, a brand-new, low-cost, lightweight damper, could become the industry standard for buildings, bridges, and many other structures susceptible to vibrating or shaking. New York City-based Thornton Tomasetti markets the technology to make buildings safer against the wind and from earthquakes. The first device to hit the market was installed in a Brooklyn building constructed in 2016.
“This is a clear paradigm shift versus what we’ve been taught,” Berry says. “It’s hard for people to give up a century’s worth of thinking. But we’ve made that century’s worth of thinking obsolete.”