34833342 Tongue Drive System Power Point

7/28/2019 34833342 Tongue Drive System Power Point

1/15

THE TONGUE DRIVE

SYSTEMASSISTIVE DEVICE


2/15

DEFINITION:

The "Tongue Drive" system is a tongue-

operated assistive technology developed

for people with severe disability to control

their environment. The tongue is

considered an excellent appendage in

severely disabled people for operating an

assistive device.


3/15

THE TONGUE DRIVE SYSTEM(TDS):


4/15

WHY THE TONGUE?

unlike hands and feet, which arecontrolled by the brain through

the spinal cord, the tongue isdirectly connected to the brainby a cranial nerve that generally

escapes damage in severe spinalcord injuries or neuromusculardiseases.


5/15

WHAT IS THIS ALL ABOUT?

The novel system allows individuals with disabilities to

operate a computer, control a powered wheelchair and

interact with their environments simply by moving theirtongues.

This device could revolutionize the field of assistive

technologies by helping individuals with severedisabilities such as those with high-level spinal cord

injuries return to rich, active, independent and

productive lives.


6/15

HOWDOES ITWORK?

To operate the Tongue Drive system,

potential users only need to be able to

move their tongues. Attaching a small

magnet, the size of a grain of rice, to an

individual's tongue by implantation,

piercing or tissue adhesive allows tongue

motion to direct the movement of acursor across a computer screen or a

powered wheelchair around a room.


7/15

Movement of the magnetic tracer attached to the

tongue is detected by an array of magnetic field sensorsmounted on a headset outside the mouth or on an

orthodontic brace inside the mouth. The sensor output

signals are wirelessly transmitted to a portable

computer, which can be carried on the user's clothing or

wheelchair.

The sensor output signals are processed to determine

the relative motion of the magnet with respect to the

array of sensors in real-time. This information is then

used to control the movements of a cursor on thecomputer screen or to substitute for the joystick

function in a powered wheelchair.


8/15

The system can potentially capture a large number oftongue movements, each of which can represent adifferent user command. A unique set of specific tongue

movements can be tailored for each individual basedon the user's abilities, oral anatomy, personalpreferences and lifestyle.

The Tongue Drive system is also non-invasive and doesnot require brain surgery like some of the brain-

computer interface technologies. There are completed trials in which six able-bodied

individuals tested the Tongue Drive system. Eachparticipant defined six tongue commands that wouldsubstitute for computer mouse tasks -- left, right, up

and down pointer movements and single- and double-click. For each trial, the individual began by trainingthe system. During the five-minute training session, theindividual repeated each of the six designated tonguemovements 10 times.


9/15

During the testing session, the user moved his or her

tongue to one of the predefined command positions

and the mouse pointer started moving in the selecteddirection. To move the cursor faster, users could hold

their tongue in the position of the issued command to

gradually accelerate the pointer until it reached a

maximum velocity.

Results of the computer access test by novice users withthe current Tongue Drive prototype showed a response

time of less than one second with almost 100 percent

accuracy for the six individual commands. This is

equivalent to an information transfer rate ofapproximately 150 bits per minute, which is much faster

than the bandwidth of most brain-computer interfaces


10/15

The researchers have also tested the ability of twelve

able-bodied individuals to operate an electric-poweredwheelchair with the Tongue Drive system. The next step

is to test and assess the usability and acceptability of

the system by people with severe disabilities.

The research team has also begun to develop software

to connect the Tongue Drive system to a wide varietyof 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 theuser to eat, sleep or engage in a conversation while

extending battery life.


11/15

ADVANTAGES OF TONGUE DRIVESYSTEM:

The signals from the magnetic sensors are linear functionsthe magnetic field, which is a continuous position dependentproperty. Thus a few sensors are able to capture a widevariety of tongue movements.

This would provide a tremendous advantage over switchbased devices in that the user has the options ofproportional, fuzzy, or adaptive control over theenvironment.

These would offer smoother, faster, and more natural

controls as the user is saved the trouble of multiple on/offswitch operations. Alternative assistive technologies thatemulate a computer mouse use an additional input devicesuch as a switch for the mouse button clicks besides theprimary method for moving the pointer.


12/15

In Tongue Drive system on the other hand, theadditional switches are unnecessary since a specific

tongue movement can be assigned to the button press.

The permanent magnet which generates the magneticfield is a small, passive, and inherently wireless

component leading to user convenience and additional

power saving mouthpiece electronics can be integrated

circuit (AISC). The AISC along with the transmitter

antenna can be incorporated into a miniaturizedpackage that may be fitted under the tongue as part

of the dental retainer.


13/15

Due to the proximity of the magnet and Hall-effectsensors in the oral cavity, the Tongue Drive system is

expected to be more robust against noise, interference,

and involuntary movements compared to alternative

technologies.

Many aspects of the system can be customized and fine

tuned through software for a particular individuals

oral anatomy, requirements, and disabilities. Therefore,

the Tongue Drive system can serve as a platform to

address a variety of needs of different individuals.


14/15

DISADVANTAGES OF TONGUE DRIVESYSTEM:

Implementation is slightly harder.

Slightly costlier.


15/15

CONCLUSION:

A tongue operated magnetic sensor based wireless assistivetechnology has been developed for people with severedisabilities to lead a self-supportive independent lifeenabling them to control their environment using theirtongue. This technology works by tracking movements of

permanent magnet, secured on the tongue, utilizing anarray of linear Hall-effect sensors. The sensor outputs are afunction of the position-dependent magnetic field generatedby the permanent magnet. This allows a small array ofsensors to capture a large number of tongue movements.Thus, providing quicker, smoother, and more convenient

proportional control compared to many existing assistivetechnologies. Other advantages of the Tongue Drive systemare being unobtrusive, low cost, minimally invasive, flexible,and easy to operate. A more advanced version with customdesigned low-power electronics that entirely fit within themouthpiece is currently under development.

Documents

34833342 Tongue Drive System Power Point