I’ve posted a number of rare metal/medical application articles over the years. I’m always fascinated by the ingenuity, understanding and patience scientists and engineers have shown in finding solutions that help others. In this piece, I’m roughly describe an innovative alliance between body piercing, orthodontics and electronics that could give people with high-level spinal cord injuries greater ability to interact with the world. The work was supported by the National Science Foundation, the National Institutes for Health and the Christopher and Dana Reeve Foundation (…Chris of Superman movie fame).
A research team at Georgia Tech’s School of Electrical and Computer Engineering is developing a wireless ‘Tongue Drive System’ that allows people to use computers and maneuver wheelchairs by moving a tiny magnet attached to a tongue stud to different regions of the mouth that are outfitted with sensors.
According to reports, an appliance similar to an orthodontic retainer has been constructed with magnetic field sensors on its four corners that detect movements of the tongue magnet. The sensors send signals wirelessly to an iPhone-type device that has software to convert the magnet positions into cursor movements on a computer or joystick movements for a powered wheelchair. The retainer is fit with a rechargeable lithium-ion battery and an induction coil to charge the battery. The circuitry fits in the space available on the retainer, which sits against the roof of the mouth and is covered with an insulating, water-resistant material and vacuum-molded inside standard dental acrylic.
Advances in the systems design also offers improved sensitivity relative to earlier versions, thus allowing the device to be programmed with many more commands. The ability to program commands is a big improvement over current ‘sip-n-puff’ devices that are simple switches controlled by sucking or blowing through a straw.
The technology has been under development for several years. ScienceDaily reported on it in June 2008, coincident with its being presented at the 2008 Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) Annual Conference. Today, it is reported that researchers have tested the system on able-bodied subjects and that they have started prequalifying candidates with high-level spinal cord injuries for further testing.
In reading some of the background to the technology, I learned that unlike hands and feet, which are controlled by the brain through the spinal cord, the tongue is directly connected to the brain by a cranial nerve that generally escapes damage in severe spinal cord injuries or neuromuscular diseases. It is also understood that tongue movements are also fast, accurate and do not require much thinking, concentration or effort.
Apparently, the system can potentially capture a large number of tongue movements, each of which can represent a different user command. A unique set of specific tongue movements can be tailored for each individual based on the user’s abilities, oral anatomy, personal preferences and lifestyle.
In this vein, the research team has also begun to develop software to connect the Tongue Drive system to a wide variety of readily available communication tools such as text generators, speech synthesizers and readers. In addition, the researchers plan to add control commands, such as switching the system into standby mode to permit the user to eat, sleep or engage in a conversation while extending battery life.
This new intraoral Tongue Drive System was presented and demonstrated on Feb. 20th at the IEEE International Solid-State Circuits Conference in San Francisco. (In earlier versions of the Tongue Drive System, the sensors that track the movement of the magnet on the tongue were mounted on a headset worn by the user.)
To fully appreciate the application of rare metals and innovation science and engineering, one really needs a have a sense of the tremendous value it can create in its broadest sense.
If you’d like to read more about the this innovative, just click on http://ceramics.org/ceramictechtoday/2012/03/05/a-magnetic-tongue-stud-and-sensor-system-for-steering-wheelchairs/ or http://www.sciencedaily.com/releases/2008/06/080630090821.htm