tactile auditory sensory substitution
DESCRIPTION
Tactile Auditory Sensory Substitution. Ryan Thome, Sarah Offutt, Laura Bagley, Amy Weaver, Jack Page BME 200/300 December 8, 2006. Client: Veronica H. Heide, Au.D. Audible Difference Advisor: Mitchell E. Tyler, P.E., M.S. Dept. of Biomedical Engineering & Dept. of Ortho-Rehab Medicine - PowerPoint PPT PresentationTRANSCRIPT
Tactile Auditory Sensory
SubstitutionRyan Thome, Sarah Offutt, Laura Bagley, Amy Weaver, Jack Page
BME 200/300December 8, 2006
Client:Veronica H. Heide, Au.D.
Audible Difference
Advisor:Mitchell E. Tyler, P.E., M.S.
Dept. of Biomedical Engineering &Dept. of Ortho-Rehab Medicine
University of Wisconsin - Madison
AbstractHigh frequency hearing loss is a problem common among people of all age groups. People suffering from this type of hearing loss often lose the ability to hear certain consonant sounds, and as a result have difficulty communicating with others. The goal of the project is to use sensory substitution, a technique for presenting environmental information missing in one sensory modality to another, to help replace this missing high frequency information. The device takes recorded information, filters it into four different channels based on frequency, then outputs all four channels to a sound card. The sound card outputs to a circuit that amplifies the sound and reduces the noise. The circuit then outputs to four transducers. Use of this device, in conjunction with the lower frequency audio information gathered directly by the user, should allow the user to better communicate by speech and hearing.
Problem StatementThe goal is to design and develop an auditory substitution device that through the use of vibro-tactile stimulation can substitute for regional frequency hearing loss, in order to aid in daily communication needs.
Sensory Substitution Presenting environmental information absent in
one sensory modality to another
Examples: Long Cane - visual navigation substitution through touch Sign Language - speech substitution through vision Braille - visual text substitution through touch
Existing Devices Tickle Talker
Electric shock on sides of fingers
One electrode per range of frequency
Tactaid 7 Vibro-tactile stimulation
on sternum, abdomen, forearm or neck
Tacticon 1600http://us.st11.yimg.com/us.st.yimg.com/I/audiologicalengineering_1903_431188
High Frequency Hearing Loss Sensorineural Normal hearing =
50 – 20,000 Hz Above 1,000 Hz is
lost Loss of ability to
hear certain high frequency consonants
Like hitting piano key with no strings
Krames Communications.
System Diagram
Amplified Analog VoltageSignal
Analog Voltage Signal Digital Signal
that has been filtered to specified frequency, amplitude, and channel divisions
Analog Voltage Signal
Microphone
Cool Edit
Person Speaking
Sound CardMulti-channelAmplifier
Transducers User
Audio Waves
Vibrational Pulses
Digital Signal
“Cool Edit” Software
Audio input is filtered for specific frequency range Becomes separate channels
1: 1.6-2.0 kHz – p, i, m 2: 2.0-3.0 kHz – ch, sh 3: 3.0-3.5 kHz – f 4: 4.5-8.0 kHz – s, th
Sound Card Turtle Beach Audio
Advantage Roadie Able to output up to
six channels Voltage output 0-60
mV
Circuit Parts
Four comparators Four transducers 10kΩ and 1kΩ Resistors
Amplifies signal Reduces noise Initial voltage output
0-50mV Amplified 11x Current draw
0-2mA
Output Piezoelectric
buzzers Placed on neck
with Bioflex® adhesive
Transducers buzz if amplitude in that channel exceeds a voltage of 1 V
Word Discrimination Joe took father’s shoe bench out he was
sitting on my lawn.
Pairs of words that can be distinguished with device Sixty versus Fifty Shirt versus Church Much versus Such Sob versus Shop
Word PairsSixty - Fifty Much - Such
Future Work Acquire and implement vibro-stimulators Minimize size Real time Specific sound analysis
References Audiological Engineering Corp. (n.d.) Tactaid 7. Retrieved 29 September, 2006 from
http://www.tactaid.com/tactaid71.html.
Better Hearing Institute (BHI). Hearing Loss- The Prevalence of Hearing Loss. 2005-2006. Date Vistied: 10/13/2006. http://www.betterhearing.org/hearing_loss/prevalence.cfm
Fairbanks, G. Voice and Articulation Drill Book. Harper & Row Publishers; New York, 1960. Pages 88-104.
Kaczmarek, K. A., Webster, J. G., Bach-y-Rita, P. and Tompkins, W. J. Electrotactile and vibrotactile displays for sensory substitution systems 1991.
Krames Communications. (1995). Hearing Aids. [Brochure]. San Bruno, CA.
“Piezoelectric Transducers.” NDT Resource Center. 19 October 2006 http://ed.org/EducationResources/CommunityCollege/Ultrasonics/EquipmentTrans/piezotransducers.htm.
Scapa. (2006). Bioflex. Retrieved 31 November, 2006, from http://www.scapana.com/productdetail.jsp?productid=3637&search=products
Webster, John G. (2003). Bioinstrumentation. Indianapolis, IN: John Wiley & Sons Inc.