Magnic Light iC brings new features to touchless dynamo bike light
By Ben Coxworth
December 30, 2013
German inventor Dirk Strothmann certainly caught some peoples' attention last year, when he released his Magnic Light touchless dynamo bike light. Instead of slowing the bicycle down by pressing on its tire, engaging magnets in its wheels, or adding friction in its hub, it's able to generate electricity simply by being close to a spinning metallic rim. Now he's about to launch the Magnic Light iC, which will offer some interesting new features.
First of all, how does the original model work? Well, as we explained in our prior article, the Magnic Light has magnets in the dynamo (as opposed to the wheel), and utilizes eddy currents. Basically speaking, these are electrical currents that are induced in a conductor, when that conductor is exposed to a changing magnetic field.
"Relative movements of magnets and neighbored conductive material induce eddy currents in the conductive material – in our case the metallic rim," said Strothmann. "These eddy currents have their own magnetic fields which are absorbed by the Magnic Light generator kernel and by this way produce electric energy."
The result was a device that was compact and wireless, like a battery-powered light, but that didn't require batteries. Its output wavered a little with the spinning speed of the wheel, however, plus it went out whenever the wheel stopped. The Magnic Light iC addresses these limitations.
Using a new onboard microprocessor, it's reportedly able to adapt to the current speed, maintaining peak efficiency at speeds ranging from 3 to 30 km/h (2 to 19 mph). When the cyclist stops, a built-in capacitor keeps the light illuminated. The iC is also said to be optimized for the LEDs used, allowing for more light per unit of power – about 160 lumens per watt.
Additionally, the lens has been redesigned in order not to blind oncoming motorists.
Strothmann is now raising production funds for the new light, on Kickstarter. A pledge of US$69 will get you a head- or tail light, while $179 will get you two front and one rear. The funding goal was met in just a few days, so commercial production does look likely.
More information is available in the pitch video below.