Blindness is serious situation. It is hard to live normal life as most information comes visually. Anyway there are lots of people who can’t see. This is where technology may help to make life more easy. Steve Hoefer has been building a device that simply pings distance to objects with pair of ultrasonic range finders. Arduino then reads data and activates two servo motors that vibrates at intensity relatively to measured distance. Device is mounted on custom glove that can be worn on wrist. So this makes it easy to scan at different heights and avoid obstacles that may be missed (like on head level). Main advantage of this system that it’s cheap enough anyone can build.