Battery Free Lighting Is Powered By The Flexing Of The Tires
LOS ANGELES, Calif. – A battery-free light invented by a teenager from Georgia could replace reflectors on the shelves of a bike. Its power comes from a bending of the tires when a motorcycle is mounted. The new device could save many lives, suggests its inventor.
Only one in five cyclists drives at night, says Thomas Dorminy. But in 2014, a huge death of cyclist deaths occurred at dusk, dawn or night, notes this 12th grader at Sola Fide High School in McDonough, Georgia (this statistic comes from the ” National Administration of Road Traffic Safety). One way to reduce The number of fatal bicycle accidents, believed the 19-year-old would be to make bicycles more visible to other vehicles.
The lights on the bikes are often designed to illuminate the road. That’s why they say. But from the side, the only visible safety devices are the reflectors attached to the spokes of a wheel. These devices reflect the light from the headlights of a car to drivers. This means that the cyclist can be largely invisible to a driver who has not turned on the lights of a car.
The teenager decided to make a camera that does not depend on the headlights of a car. It shines all by itself. Better yet, it never needs a battery, because it is powered by small pieces of a piezoelectric material (PEE-eh-zoh-eh-LEK-trik). When such materials bend, the electrons move inside to generate an electrical current. (The prefix “piezo” comes from the Greek word piezein, meaning “press” or “press”.)
Thomas presented his research, here at the Intel Engineering and Engineering International Fair. ISEF was created by the Society for Science & the Public and is sponsored by Intel. The competition allows students from around the world to show their winning science fair projects. (The Society also publishes Science News for Students.) Last week, nearly 1,800 high school students from over 75 countries participated in great awards and the ability to share their research results.
In his design, Thomas connected three small pieces of piezoelectric material and placed them between the tire of the bike and its inner tube. Each time the tire turns down to come into contact with the street or sidewalk, presses the piezoelectric bits. The current generates light from a small band of light-emitting diodes or light-emitting diodes. These lights are attached to the spokes of the bicycle wheel, where a reflector normally draws attention to the wheels. When the bicycle rolls the piezoelectric pieces, the materials retreat in their normal shape. This creates a second increase in current and another flash.
The LED strip of the device is approximately 5 centimeters (2 inches) long. When seated, the band is only about one-fifth the size of a standard bicycle reflector, says Thomas. But when the bike wheel turns, the incandescent LED strip creates a ray of bright light that measures nearly 150 square centimeters (23 square inches). This is about six times the surface area of a reflector. In addition, this glow would be brighter than a standard reflector. So Thomas says it is almost certain that his camera would be seen more easily than the reflectors used on bicycles today.
Credit: Science News for Students