Destructive earthquakes in Mexico, Chile and Russia in 2017 underscored the importance — and urgency — of the kind of innovative research Dr. Courtney Peckens is pursuing in VanderWerf Hall’s Haworth Engineering Center.
Supported by a three-year grant from the National Science Foundation and a Nyenhuis Grant from Hope College, Peckens is developing and testing wireless sensor nodes that she hopes will lessen the impact of earthquakes on civil infrastructure like buildings and bridges.
“The sensor nodes detect the motion of a structure due to an earthquake,” Peckens explains. “This research is looking at developing ways of mitigating the effects of that earthquake by implementing different control algorithms. As a building is moving, you want to apply a counterbalancing force to it in order to offset the earthquake’s effect.”
Other engineers have developed a variety of devices called “actuators” that can apply that counterbalancing force. The purpose of Peckens’ wireless nodes, which are about half the size of a cell phone, is to reduce the amount of computational time required to make a control decision based on the structure’s movement. This will allow the actuators to respond more quickly and produce more effective control. As earthquakes are in general very rapid, any time reduction in this process is desirable.
What makes Peckens’ research unique is that her engineering designs are based in part on the human nervous system, which makes complex decisions in quick, simple ways.
“In general, engineering is not naturally linked to biology,” she acknowledges. “But in recent years there’s been a fairly large push to do biology-inspired engineering. As the field of biology makes more and more advances, it’s easier for people to draw more parallels between the two.”
Hope students Anne O’Donnell ’18 and Taylor Rink ’18 helped Peckens put her theories to the test for a 10-week research program in summer 2017. In her laboratory they used a small “shaker table,” placed an even smaller mockup of a one-story structure on top of it, and put the shaker table into motion to simulate various earthquake scenarios.
“In my lab, we do initial analysis through computer simulations, but then everything we do has to be validated in experiments,” Peckens says. “Something may work perfectly in simulation, but doing it experimentally is an entirely different thing.”
Peckens, who advises Hope’s student chapter of Engineers Without Borders, concedes that her active control systems may not be adopted in all structures. “Generally there’s more upkeep needed, so building owners might prefer passive techniques. Taller buildings would be more critical,” she says.
“The ideal outcome would be no damage. But earthquakes are really variable, so a large minimization of damage would be great, for sure.”