Tacit hand device steers blind to safety (w/ video)

Sep 15, 2011 by Nancy Owano report

(PhysOrg.com) -- A hand device called the Tacit can help the blind and visually impaired move around safely in complex environments. Wrist-mounted, the device uses ultrasonic sensors mounted above the knuckles that can pick up the distance of objects from one inch to 10 feet away and then translate that distance to pressure on the wrist--the closer the object, the more pressure on the wrist. Pressure is applied on the right or left side of the wrist to help the user determine where the obstacle is located.

The can be strapped on to either hand and one-size-fits-most. The device shows a fast , in fractions of a second. A blind or visually impaired person can sense what is in the immediate area with a sweep of the hand. The , Steve Hoefer, chose the word Tacit to describe the haptic-feedback , he wrote, because "it just seemed like an appropriate name that’s a lot shorter (though less descriptive) than 'Hand-Mounted Haptic Feedback Sonar Obstacle Avoidance Assistance Device'.”

As interesting as the device is, what has attracted much buzz is the fact that the device, more formally called The Tacit Project, is under a Creative Commons License, and the project has been dedicated as a DIY idea for others to build. Hoefer's site, Grathio Labs, has posted source code, a list of parts, and detailed diagrams, with an invitation to make the device. "I am active in the Open Source software and hardware and encourage community innovation and creativity," he says on his site. He is using the Creative Commons BY-NC-SA license, which he explains as a “Don’t be a jerk” license. "In short: Make it, learn from it, teach it, improve it, modify it. Just share what you do, give credit, and don’t sell any without contacting me first."

As such, Hoefer is straightforward about where the device, which is a prototype, is of merit and where it needs improvements. "It's not perfect but it works and it can be better." It could easily be made about half the size, he said; another challenge is the fabric he chose, neoprene. He chose neoprene because it is a solid, durable, shock-absorbent base for electronics, but neoprene is not easy to sew. "It likes to drop stitches like crazy on a sewing machine."

As for device accuracy, Hoefer says that lasers would have provided the most accuracy, but would be too costly, in his opinion. The cost of materials for Hoefer's prototype is $65. "For now ultrasonics work best at this price."

The hand device follows an earlier idea by Hoefer for a headband with ultrasonic sensors and vibration motors around the
circumference of a headband; the motors vibrated faster when close to an obstacle. The headband had two flaws which led Hoefer to try something different. The most dangerous obstacles, such as furniture that the blind person can trip over, are not at head level. Also, said Hoefer, "vibrating motors stuck on your skull will drive you insane quickly."

The Tacit device's learning curve is measured in seconds, according to Hoefer. He said everyone who has worn it figured it out immediately.

Explore further: Audi tests its A7 driverless vehicle on Florida highway

Related Stories

New device puts vision impaired in the picture

Apr 28, 2011

(PhysOrg.com) -- Visually impaired people may soon have greater access to graphical information thanks to a new device developed by Monash University’s Faculty of Information and Technology.

Enabling the blind to find their way

Oct 24, 2008

(PhysOrg.com) -- “Eyes on the future” is the mantra of the ‘World Sight Day’ held this month to raise awareness of blindness and vision impairment. New technologies, developed by European researchers offering the ...

Robotic Hand That Senses Touch (w/ Video)

Oct 21, 2009

(PhysOrg.com) -- Developed by researchers at Lund University in Sweden and Scuola Superiore Sant'Anna in Italy, the Smart Hand project has given patient, Robin af Ekenstam (see video) the sense of touch in ...

Recommended for you

Chinese smartphone makers win as market swells

10 hours ago

Chinese smartphone makers racked up big gains as the global market for Internet-linked handsets grew to record levels in the second quarter, International Data Corp said Tuesday.

Full appeals court upholds labels on meat packages

10 hours ago

(AP)—A federal appeals court has upheld new government rules that require labels on packaged steaks, ribs and other cuts of meat to say where the animals were born, raised and slaughtered.

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Jotaf
not rated yet Sep 15, 2011
Awesome! It's so simple yet it has a lot of potential. The fact that it's DYI/open-source is also inspiring. Someone who thinks his inventions should be for the whole world and not just to make him rich. It also doesn't prevent him from making some profit by selling pre-built devices, even setting up a company or signing a contract with one willing to do it.
braindead
not rated yet Sep 16, 2011
Well done - this might also be a cheap and cheerful device for not just the vision impaired but also for first responders navigating in limited visibility conditions - eg smoke-filled air - in which case ultrasonics will work where lasers would not.