Tacit is a sonar-enabled glove that helps the blind to detect when objects are nearby. Developed by local maker, Steve Hoefer, Tacit uses sound navigation and ranging to depress pads which alert wearers of their surroundings.
Built using an Arduino Pro, servos and a whole lot of ingenuity, Steve provides the complete instructions for making Tacit on his blog.
Tacit was developed with both form and function in mind. The first prototype was built as a headband, but as Steve explains on his blog, this couldn't work in the long term. Most serious obstacles to the blind occur closer to waist level and "vibrating motors stuck on your skull will drive you insane quickly". Having never placed a set of vibrating motors on my head, I am sadly without first hand experience (though the thought alone gives me a headache).
Steve put together this awesome video explaining Tacit and how it can be used: