# Researchers Unveil the Science Behind Riding a Bike

We’ve all heard the expression “it’s like riding a bike?” It typically implies something that is a learned task that once mastered, you never forget how to do.  We all initially struggled as kids to learn the proper ratio of speed and balance required to remain upright when trying to ride a bike for the first time. There were probably a few spills and tears in the process, but eventually we all mastered the art of riding a bike.

Turns out, however, that riding a bike is more science than art. Researchers from the U.S., Holland, and England took more than three years to arrive at a mathematical formula to explain riding a bike so don’t feel bad if you took a few weeks—and a few spills—to learn how to ride yourself. The formula reveals the complex forces at work that cyclists—even as relatively young children—seem to master instinctively.

Riding a bike more science than art

In simple terms, the phenomenally complex equation can be explained as: inertia forces + gyroscopic forces + the effects of gravity and centrifugal forces = the leaning of the body and the torque applied to the handlebars of a bike. In other words, if you do not pedal fast enough to keep moving while keeping the bike straight, you’ll fall over. Warning: do not try to explain this to your risk-adverse four-year-old before he or she embarks on their maiden voyage on their bike.

Dr. Arend Schwab of Delft University of Technology in the Netherlands, one of the study’s key researchers, developed the equation and explained how it solves a question that is as old as bicycles themselves. “People more than a hundred years ago were trying to figure out why a two-wheeled bicycle, given forward momentum, like a push, would seem to balance by itself.”

He explains how the results of this research hold the potential to improve bike design in the future. “Using our equation, we can simulate the motion of a bike and predict whether it will remain stable or not under certain conditions – including if it goes over a bump, or is hit by a gust of wind,” says Schwab. “This equation is aimed at enabling a bike designer to change certain features and to see the overall finished effect on the bike without having to actually manufacture it first.”

For example, if an engineer were designing a folding bike with smaller wheels, or one with a shorter wheelbase, this equation would enable him to interpret how design changes will affect the stability and behavior of the bike.

However, riding stability doesn’t only come from bike geometry plus human input. The Gyrowheel, a gyroscope within a wheel that its manufacturers claim is self-righting, is now commercially available. This technology also appears in the new, electrically powered Honda U3-X—a micro-wheeled device that claims to allow movement in any direction using only the body’s sense of balance. Check out this video to see it in action. You can read more about Delft University of Technology’s bicycle dynamics study here. Also, check out this “Ride to Success” infographic  to get a step-by-step look at the advantages of designing bikes in 3D versus 2D.

University’s students use SOLIDWORKS to design class projects

Delft University’s Industrial Design and Mechanical Engineering departments have used SOLIDWORKS Education Edition and Simulation software since 2009. Since then the University has implemented over 6,000 licenses of the software, which is being used by students to design class projects.

University professors are also using integrated SOLIDWORKS Simulation tools to introduce students to analysis concepts sooner than in the past. “The moment that we switched to SOLIDWORKS, we began exploring the possibilities for integrating SOLIDWORKS Simulation in the curriculum,” says Anton van Beek, professor of Mechanical Design in the University’s Department of Precision and Microsystems Engineering.

“We successfully introduced Simulation during first-year courses at the same time that we introduced SOLIDWORKS. “When students have the opportunity to compare the analytically derived stresses and strains with results obtained using SolidWorks Simulation, they learn more autonomously,” says van Beek. “The certification programs offered by SolidWorks for design and simulation are also a great advantage in helping students build their curriculum vitae for entry into the real engineering world.”

#### Mike Fearon

Senior Manager Brand Offer Marketing, Dassault Systemes SOLIDWORKS. Video game world champion and whisky advocate. I like turtles.