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You’ve heard of magnetic orientation in migrating birds, the theorized “sixth” sense that allows them to see the earth’s magnetic field using deposits of magnetite in their beaks. To see what this experience might be like for a human, you can build a north-sensing feedback device into a belt using some pager motors, an Arduino, and a digital compass.

Last night I built a haptic compass, also known as the Clown Belt. This is a belt which features twelve vibrating pager motors equally spaced around the perimeter of the belt. The control box uses a digital compass to determine which way is north, and continuously buzzes the appropriate motor. The effect is subtle but noticeable. I feel like I’ve been granted a strange new sense of direction.

The belt has additional features: it can be connected via serial to my iPhone which delivers up a bearing to an arbitrary destination. I have a first generation iPhone, which means my current location is highly approximate, but for distant locations it works great. It can also be controlled wirelessly over an XBee RF link, but the peculiar application of that is the subject of a future post.

I first heard of this hack in a March 2007 Wired article, titled Mixed Feelings, which describes a few experiments that show how our traditional 5 senses can be tricked into proxying data from external extra-sensory devices:

The world is full of gadgets that detect things humans cannot. The hard part is processing the input. Neuroscientists don’t know enough about how the brain interprets data. The science of plugging things directly into the brain — artificial retinas or cochlear implants — remains primitive.

So here’s the solution: Figure out how to change the sensory data you want — the electromagnetic fields, the ultrasound, the infrared — into something that the human brain is already wired to accept, like touch or sight. The brain, it turns out, is dramatically more flexible than anyone previously thought, as if we had unused sensory ports just waiting for the right plug-ins. Now it’s time to build them.

Vibrating belts can give you the ability to sense direction. Rare earth magnets, implanted in your fingertips, can enable you to detect the electromagnetic field surrounding live AC wiring. If you could choose to sense anything beyond the typical 5 human senses, what would it be, what device could you build to detect it, and how would you jack your existing senses into that new data feed?

On the Haptic Compass



  1. microdot says:

    Neat Idea, just don’t use it to find your way to the airport.

  2. bekathwia says:

    We made belts similar to this in a class back in college so that a group of people could “flock” together like birds. One person had a transmitter capable of instructing the group to go one of four directions, and we all had pager motors in those positions on the belts. I tell ya, though, most of us ended up sick to our stomachs from all of the belly-vibrating. Info is here:

  3. screaminscott says:

    I’ve always wondered if you could use this idea to provide information about the area around your car.

    For example, wouldn’t it be great to tell when another car is in your blind spot? Or how close that car is behind you? All without looking?

  4. Anonymous says:

    I’m not technically savvy enough to make one of these. Nor do I really have the time. That said, if you could somehow figure out a way to mass produce this or even on a slightly smaller scale for a relatively affordable price, I could see this being very profitable. Just the curious factor alone would entice most “geeks” and the promises of developing extra-sensory … senses would make it appeal to more people.

    Regardless… I want one! lol

  5. Bhasker Raj says:

    Haptics is proving to be a successful technology and applications are finding in various fields from medical, to space, military, to homes.

    The future of haptics applications are bright.