Low Cost CROS Hearing Aid

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  Low Cost CROS Hearing Aid

Project Description

Inspiration
The traditional CROS hearing aid is intended for individuals with minimal hearing in one ear and full hearing in the other. Current versions are rather expensive, especially when compared to normal hearing aids that amplify the surroundings. We were inspired to create a low cost version that uses open source components to mimic the traditional CROS hearing aid.

Goal
We set out to create a hearing aid that takes in sound from one side, which represents the ear with minimal hearing, and transmits it wirelessly to the location of the ear with full hearing, and output this sound. This ensures that the user is able to get a full range of sounds when only one ear is able to hear.

Description
Our project takes in a frequency using a microphone, utilizes frequency processing code to identify this frequency as well as the corresponding music note, and outputs this frequency through a buzzer. It also sends the identified music note to the user to be viewed on their phone. .

Design Process and Iterations

First Iteration (MVP)
We were just familiarizing ourselves with sound and how it is utilized in electronics. The MVP utilized the microphone to just sense if a sound was present (just on or off), and if so, the buzzer output sound.

Second Iteration
Once we gained familiarity with these sensors, we began to look for open source code that could be used to elevate the the sound sensing capabilities. For this iteration, the microphone was able to read in a frequency through the microphone and output this same frequency through the buzzer.

Third Iteration (Final Product)
The final iteration utilizes the same functionality and code as the second iteration, but integrates an IoT component that displays the played music note on the user's phone.

Challenges

We did not realize how complex receiving and transmitting sound would be, and needed to reduce our project goals to just frequency through a buzzer rather than words and complex sounds through a speaker. We also faced difficulty with the IoT component and transitioned from the Feather to Twilio to Adafruit after difficulty with connecting it. Even so, there was a lot of troubleshooting and trials to get the Adafruit to work, especially as neither of us had previous experience with it. We learned that Adafruit needed to be connected to the computer in order to work, so one of our final iterations did not include this component as we wanted to show what it would be like if the hearing aid was independently powered by a 9V battery.

Technology Description

The hardware includes an Arduino Uno, Wifi Shield 101, KY-037 High Sensitivity Microphone, Adafruit Bluefruit LE UART Friend, passive buzzer, potentiometer, resistor, and connective wires. For the software, the microphone processing code was modified from open source code created by Clyde A. Lettsome.

Lessons Learned

We learned a lot about how sound works from an electrical engineering perspective and how challenging it can be to get sound to actually work. Because the hardware was relatively simple, most of our learning came from the software side. We learned how to interpret and modify rather complex open source code, integrate it with other components like the buzzer, and how to utilize the Adafruit Bluefruit platform.

What's next for Low Cost CROS Hearing Aid

If this project was continued, we would hope for more complex sound sensing that is able to take in words and other noises and produce these sounds through a speaker. We also would attempt to take in sound from two microphones, representing the working and deaf ear, merge these sounds, and output them through one speaker.

Built With

• arduino