Cyclists can already choose between plenty of cheap spoke-mounted LEDs that turn their bike wheels into highly-visible "rings of light" while they're turning. California-based startup MonkeyLectric has given the tech a new slant, though, with wheel lights that power up automatically – and only when needed.
The result of a successful Kickstarter campaign, the new A15 Automatic Monkey Light consists of an LED module that is zip-tied to the spokes, along with a cylindrical battery unit that's likewise zip-tied to the wheel hub. An electrical cable, which is wound around one spoke, connects the two.
There are two RGB LEDs on each side of the LED module, with a light output of 40 lumens per pair. Thanks to an ambient light sensor and an accelerometer within the module, they only come on once it gets dark outside, and only when the wheel is in motion. This feature saves the user from having to power them up and down manually, plus it's intended the stretch the amount of time required between battery charges.
Each USB-charge should reportedly be good for up to 17 hours of run-time, and the lithium battery can be removed from its hub-mounted housing when it needs juicing up.
Utilizing two pushbuttons on the LED module, users can select between 23 light colors/patterns. These include four modes in which the lights change between different colors, based on the bike's speed.
The whole system weighs a combined 105 grams (3.7 oz), it's waterproof, and fits on wheels sized 16 inches or larger. It's available now via the link below, priced at US$40 per wheel.
Source: MonkeyLectric
I am also surprised they do not use the centrifugal force to generate electricity locally.
I've not seen a generator that works on centrifugal force.