A photo of the Flybar
Image courtesy SBI Enterprises, Inc./FLYBAR
When compared to toys like in-line skates, scooters and electric skateboards, the pogo stick seems old-fashioned. But thanks to a complete design overhaul that includes replacing the tried-and-true steel coil springs with elastic bands, the pogo stick has officially entered the 21st century. It even has a newer, hipper name -- the Flybar.

What else makes it different from a traditional pogo stick? How can people bounce so high with the Flybar, and is it safe? Why are extreme sports enthusiasts excited about it? We'll answer these questions and more by examining this new twist on a traditional toy.

At first glance, the Flybar looks completely different from a pogo stick. Its aluminum housing covers its internal workings and gives it a futuristic look. The difference translates to performance, too. Flybar doesn't simply bounce riders a few inches off of the ground -- it launches them to spectacular heights.

Given the Flybar's amazing height potential, you might think there's some revolutionary science at work. But the Flybar uses the same scientific principle as a traditional pogo stick: elasticity, or the ability of a material to return to its original shape after its shape changes. Technically, any solid can exhibit elastic behavior, but certain materials are much more elastic than others. Brittle objects, such as those made of plastic, are only slightly elastic. When they reach their elastic limit, they break. Their limited elasticity makes them brittle.

Springs and elastic strings, however, are highly elastic, which means their shape can be deformed quite a bit before they reach their elastic limit. Because they stretch, they can store energy that can be used to do work in the future. This type of stored energy is elastic potential energy. As elastic potential energy is released, it is converted into kinetic energy, or energy of motion. Pogo sticks take advantage of this energy conversion process. As a rider bounces on a pogo stick, his weight and the force from his legs are stored as potential energy in the elastic material, either a spring or an elastic string. When the elastic material recoils, all of the stored energy is transferred back to the rider, who uses the thrust to bounce higher.

Strings vs. Springs
Both traditional pogo sticks and Flybars are capable of storing large amounts of potential energy, but they don't do it in the same way. That's because a pogo stick uses a steel coil spring, while the Flybar uses elastic strings, essentially giant rubber bands called thrusters. Springs and elastic strings differ in one critical way: springs can be compressed as well as stretched, but elastic strings can only be stretched.

Graph showing the differences between springs and strings behavior

What are the implications of this difference for a pogo stick? When a rider bounces on a traditional pogo stick, his weight and force from his legs compresses a steel spring. As the spring compresses (shortens), it stores energy. When the rider pulls up, or stops applying force to the foot pegs, the spring recoils, providing thrust to help the rider bounce higher.

When a rider bounces on a Flybar, he also uses his weight and force from his legs to provide the energy necessary to bounce. Instead of compressing a spring, he stretches (lengthens) a bundle of thrusters. As the thrusters stretch, they create tension and store energy. When he pulls up, the thrusters return to their natural length, releasing the tension and propelling the rider into the air. The elastic strings in the Flybar operate like a trampoline, with each string capable of generating up to 100 pounds of thrust.

Next, we'll look at the Flybar inside and out.

History of the Pogo Stick
Although the original pogo stick came about in the late 1820s, a practical design of the toy did not arrive until 1919. George B. Hansburg, an Illinois toy designer, responded to a request from Gimbel Bros. Department Store to improve upon a wooden pogo stick it had imported from Germany. Hansburg replaced the wood with metal, enclosed the spring and applied for a patent. Then he began producing the toy himself in an Elmhurst, New York factory. He called his company SBI Enterprises and continued to manufacture pogo sticks until he sold SBI in 1967 to Irwin Arginsky.

Arginsky kept the SBI name and the same basic pogo stick design, but he relocated the factory to Ellenville, New York. SBI still manufactures traditional pogo sticks alongside the newest addition to the pogo family -- the Flybar 1200. The Flybar was not an in-house innovation. Bruce Middleton, an MIT-trained physicist and inventor, approached Arginsky in 2000 with an idea for an improved pogo stick design. Middleton proposed that they replace the steel spring with a patented system of rubber spring elements. Arginsky saw the potential immediately and began working with Middleton to develop the first prototype.

Soon after, eight-time World Cup Champion skateboarder and longtime pogo fan Andy Macdonald joined the project team. After four years of research and development, SBI Enterprises, with the help of Middleton and Macdonald, arrived at the Flybar 1200 design and began selling the product in September 2004