Light up biking vest shows impatient drivers how fast you are going

nighttime_bike_speed_vest

[Mykle Hansen] is an avid cyclist, and safety is a big concern for him. He says that bicyclists often receive a lot of honks and grief from passing motorists because they perceive them as moving far slower than they really are. According to [Mykle], this misjudgment can result in “right hook” collisions, which kill several bicyclists each year. To increase his nighttime visibility and to give drivers a better idea of how fast he’s traveling, he constructed a bicycling vest that displays his current speed in large 7-inch tall numbers.

He uses an off-the-shelf speedometer to get his current speed, feeding that data to an Arduino tucked inside his vest. The Arduino then lights the appropriate EL wire digits to relay his speed to motorists behind him.

It seems to work pretty well if the video below is any indication, and there’s no denying that it will catch a driver’s attention at night. If you’re thinking of making one for yourself, check out his Make:Projects page for a complete look at how it was put together.

Continue reading “Light up biking vest shows impatient drivers how fast you are going”

Sustainability Hacks: Solar panels built from old windows and factory rejects

diy_solar_panels

The crew over at The Tech Junkies recently took another look at solar power and thought that the pricing had come down enough for them to consider powering their entire shop via the sun. Cheaper or not, they still didn’t want to pay retail for solar panels, so they decided to build their own instead.

They scoured eBay for a bit and scored a nice batch of “production error” solar cells for about $0.25/watt, which is a great deal. After unpacking and sorting the cells, they began fitting them into a set of old window panels they had sitting around their shop. The cells were wired together using tabbing wire, and after a quick test to ensure everything was working correctly, the panel was permanently set using epoxy.

In its current state, they estimate that their panel can generate 35 watts of power, though they have a few design changes in mind to raise that number a bit. The total cost was roughly $375 for enough materials to build 9 panels, which is pretty reasonable.

Be sure to check out their blog for a quick overview of what it takes to build a solar panel if you’re thinking of putting together one of your own.