DIY Safety Aids No Bike Injunction Can Stop


Until the city certifies its Draft Environmental Impact Report in a few months and Judge Busch lifts the bicycle injunction, we have to get more resourceful about maintaining our safety as cyclists.

Mykle Systems Labs has fabricated a speed vest that shows a cyclist’s speed to vehicles that approach from behind.  It both increases visibility and demonstrates to motorists how much slower the bicycle is moving than the vehicle, which many motorists probably don’t realize if they don’t also ride.

The system consists of a wheel speed sensor, a wearable numeric display
and a small computer that does the thinking. The computer is an Arduino: an open-source embedded computing platform powered by an Amtel
microcontroller. It runs for 6 hours on a 9 volt battery, and is the size of a wallet.

Points for ingenuity, but lacking the visual pop that would really get a driver’s attention.

Then there’s a wireless brake light and turn signals, though from this video, I’d imagine drivers won’t understand that the solid red is meant to indicate the cyclist is slowing down.  The turn signals also look more like a funky color sequence than an indicator to drivers that you intend to turn.

When I lived in New York City and experienced harrowing encounters with drivers almost daily, I often fantasized about mounting a scrolling red LED billboard behind my bike seat that could display what I thought about the heavy horn honking, the unsafe passing, and the tailgating.  Only problem I could foresee was typing missives and riding at the same time.  I usually settled for universally understood hand signs.

Commute By Bike last year posted some great photos from a commenter named "Ghost Rider" who illustrated Florida’s three-foot passing lane law by painting a yardstick in bright orange and fastening it perpendicular to his seat post.  He then scrawled two different messages on either side of the yardstick, one kindly asking drivers to give him the required distance by law and another with more frank instructions.



Still, cyclists being overtaken by motorists only accounts for 9 percent of total bike crashes; turning conflicts are the major concern.  So we still need the injunction lifted, we need good bike facilities like separated lanes and colored lanes, and bicycle-priority signal timing.


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