Hearing Alerter

Inspiration

When my partner and I went to a concert last week, we were right up at the front by the speakers and stage. The night was great except for our hearing afterwards. Being so close to the speakers and constantly being in such a loud environment has harmed our hearing. To combat hearing loss and help others be more mindful of their sound environment, we wanted to make a physical gadget to warn the user of loud environments and possible imminent hearing damage.

What it does

The Hearing Alerter constantly uses a microphone to listen to the environment. When it detects a loud noise or a long persistent environment of noise, it displays a warning to the user and alerts them with a vibration. With a clip, it can be worn on your clothes, keeping you aware at all times.

How we built it

To build it, we first laid out all of the functions and ideas we had for the gadget. Then we made a list of all the features we thought were within our scope and ones which would be nice to have as well. From there, we broke the system into a main loop and several libraries which handled the displays and rolling averages for tracking environmental noise. With everything laid out, we split up our work, working on the main file and the library files. When everything was written, we went looking for sensors which would work well for the application, first we considered the ifMagic sensors, however our application involved a separate MCU and additional peripherals which didn't mesh well with the system. We then pivoted to a analog microphone sensor and a buzzer which we believed to have been a piezoelectric vibrator. Putting all of the pieces together along with some displays, a perf board, and a bread board, we have the final prototype.

Challenges we ran into

The largest challenge we ran into was not being able to integrate the different sections of code with each other and the physical hardware. We utilized a library called U8g2 and two custom written libraries. Getting the desired result from every library and balancing the main loop's logic proved to be very challenging. We also only pieced together the prototype late into the hackathon since the original sensors we had planned to use were not compatible with our application.

Accomplishments that we're proud of

Being first time hackathon attendees, we're proud to have something which is a physical project that we can improve on as well as the volume of work we've done in such a short amount of time. In personal projects outside of the hackathon, it typically takes many more days to accomplish and piece together less than what we have done this weekend. Another accomplishment that we're proud of was a work around for not having a vibration module for the project. Originally we intended to use the ifMagic vibration modules, however those were not compatible with our idea. Then we had sourced what we believed was a piezoelectric vibrator but turned out to be a buzzer. To keep along the lines of haptic feedback, we used a motor with an offcenter weight to create a vibration when spun fast. The motor is controlled with a MOSFET using a PWM signal from the MCU.

What we learned

We learned a lot about what it takes to bring a project from beginning to end. Having gone through all of the planing for the main loop and logic, but still having troubles integrating the different sections, we learned to better think out the interactions between modules whether physical or software. We also learned to better allocate time for projects and the bounds of our scope in a weekend. Coming into this weekend we had many grand plans about implementing a project involving machine learning object recognition and ocr which we decided against early on. After this hackathon, we much better understand our scope and time management.

What's next for Hearing Alerter

We hope to continue to work on it, first focusing on getting it all to function and eventually getting the footprint down. We originally had in mind a smaller form factor which would be more wearable / fashionable.

Built With

• arduino
• cpp
• teensy
• u8g2