Origami, the Japanese art of folding paper, doesn’t seem like it could help stop bullets. But mechanical engineers at Brigham Young University have developed a new ballistic shield design for law enforcement officers that incorporates origami folding structures–and can stop bullets from a .44 Magnum, one of the most powerful handguns.
Developed by Dr. Larry Howell and Terri Bateman of the Compliant Mechanisms Research Lab, the shield uses 12 layers of Kevlar–the same material used in bulletproof vests and body armor–in what is known as a Yoshimura folding pattern, which enables a flat material like paper to form a curved shape.
While typical ballistic shields are often flat, hard steel surfaces that don’t cover the entire body, the lab’s origami-inspired shield stands up on its own and can shield two or three officers from gunfire. It weighs 55 pounds, compared to some other folding shields which weigh more than 100 pounds. And unlike some models that require time for set up, or are unwieldy to transport, it takes only seconds to deploy. Locking mechanisms on the back of the shield snap into place with a few shakes of the shield prevent it from falling over, and it compactly folds when not in use, making it easy to store.
Howell has been working with origami as part of his research on “compliant mechanisms,” or materials that fold or bend, for five years. “We noticed that this ancient art of origami, that these artists over the centuries have discovered some ways of achieving motion that we would not have discovered using traditional engineering approaches,” he says. “There are some real advantages: increased precision, decreased cost, reduced weight.”
For instance, Howell and his team are working with NASA on solar panels for space, and have also used origami-based design to create implements used in minimally invasive surgery. Since origami is a compliant mechanism, surgical tools based on the patterns tend to enter the body more naturally. “Most of your internal organs are compliant mechanisms: your heart is a pump that’s continual,” he says. “If you were to build [a valve] using traditional engineering, you would have all sorts of bearings and hinges–but that’s not how nature does it.”
The shield project began in the summer of 2016. “It doesn’t seem like it would help in security,” Bateman says of the design. “It seems flimsy.” But their experience studying the mechanical properties of origami led them to believe that one of the patterns could enable a shield that was lighter, quicker to deploy, and more compact to store.
The two engineering professors and a team of students began by speaking with security personnel and police officers about the problems they had with many existing shields, which are cumbersome, heavy, and don’t entirely protect officers. After modeling and experimenting with several different folding patterns, the team settled on the Yoshimura pattern because it creates a curving structure, which lets the shield stand up on its own while protecting officers’ sides. During testing, the team observed as officers shot about 24 bullets from 9 mm, .357 Magnum, and .44 Magnum guns at the shield, aiming primarily at the folds and hinges in an attempt to knock it over. Not even one of the most powerful handguns on the market, the .44 Magnum, could tip the shield. Its layers of Kevlar–which cover 24 square feet when laid flat–absorbed the force of the bullet.
Howell believes that the shield has applications outside of law enforcement. It could also be used to protect children in schools during active shooter situations, especially because it can be stored compactly in a closet and deployed quickly. He has filed for a patent and is actively looking for commercial partners, which will allow him to develop the shield further. It can only defend against handguns and pistols, though. The current prototype wouldn’t be able to withstand an attack from the assault rifles often used in the military, which have smaller, sharper bullets. Integrating protection against those kinds of weapons is the next step, though doing so will increase the weight and cost of the shield.